Version:  2.0.40 2.2.26 2.4.37 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16

Linux/drivers/firewire/ohci.c

  1 /*
  2  * Driver for OHCI 1394 controllers
  3  *
  4  * Copyright (C) 2003-2006 Kristian Hoegsberg <krh@bitplanet.net>
  5  *
  6  * This program is free software; you can redistribute it and/or modify
  7  * it under the terms of the GNU General Public License as published by
  8  * the Free Software Foundation; either version 2 of the License, or
  9  * (at your option) any later version.
 10  *
 11  * This program is distributed in the hope that it will be useful,
 12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14  * GNU General Public License for more details.
 15  *
 16  * You should have received a copy of the GNU General Public License
 17  * along with this program; if not, write to the Free Software Foundation,
 18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 19  */
 20 
 21 #include <linux/bitops.h>
 22 #include <linux/bug.h>
 23 #include <linux/compiler.h>
 24 #include <linux/delay.h>
 25 #include <linux/device.h>
 26 #include <linux/dma-mapping.h>
 27 #include <linux/firewire.h>
 28 #include <linux/firewire-constants.h>
 29 #include <linux/init.h>
 30 #include <linux/interrupt.h>
 31 #include <linux/io.h>
 32 #include <linux/kernel.h>
 33 #include <linux/list.h>
 34 #include <linux/mm.h>
 35 #include <linux/module.h>
 36 #include <linux/moduleparam.h>
 37 #include <linux/mutex.h>
 38 #include <linux/pci.h>
 39 #include <linux/pci_ids.h>
 40 #include <linux/slab.h>
 41 #include <linux/spinlock.h>
 42 #include <linux/string.h>
 43 #include <linux/time.h>
 44 #include <linux/vmalloc.h>
 45 #include <linux/workqueue.h>
 46 
 47 #include <asm/byteorder.h>
 48 #include <asm/page.h>
 49 
 50 #ifdef CONFIG_PPC_PMAC
 51 #include <asm/pmac_feature.h>
 52 #endif
 53 
 54 #include "core.h"
 55 #include "ohci.h"
 56 
 57 #define ohci_info(ohci, f, args...)     dev_info(ohci->card.device, f, ##args)
 58 #define ohci_notice(ohci, f, args...)   dev_notice(ohci->card.device, f, ##args)
 59 #define ohci_err(ohci, f, args...)      dev_err(ohci->card.device, f, ##args)
 60 
 61 #define DESCRIPTOR_OUTPUT_MORE          0
 62 #define DESCRIPTOR_OUTPUT_LAST          (1 << 12)
 63 #define DESCRIPTOR_INPUT_MORE           (2 << 12)
 64 #define DESCRIPTOR_INPUT_LAST           (3 << 12)
 65 #define DESCRIPTOR_STATUS               (1 << 11)
 66 #define DESCRIPTOR_KEY_IMMEDIATE        (2 << 8)
 67 #define DESCRIPTOR_PING                 (1 << 7)
 68 #define DESCRIPTOR_YY                   (1 << 6)
 69 #define DESCRIPTOR_NO_IRQ               (0 << 4)
 70 #define DESCRIPTOR_IRQ_ERROR            (1 << 4)
 71 #define DESCRIPTOR_IRQ_ALWAYS           (3 << 4)
 72 #define DESCRIPTOR_BRANCH_ALWAYS        (3 << 2)
 73 #define DESCRIPTOR_WAIT                 (3 << 0)
 74 
 75 #define DESCRIPTOR_CMD                  (0xf << 12)
 76 
 77 struct descriptor {
 78         __le16 req_count;
 79         __le16 control;
 80         __le32 data_address;
 81         __le32 branch_address;
 82         __le16 res_count;
 83         __le16 transfer_status;
 84 } __attribute__((aligned(16)));
 85 
 86 #define CONTROL_SET(regs)       (regs)
 87 #define CONTROL_CLEAR(regs)     ((regs) + 4)
 88 #define COMMAND_PTR(regs)       ((regs) + 12)
 89 #define CONTEXT_MATCH(regs)     ((regs) + 16)
 90 
 91 #define AR_BUFFER_SIZE  (32*1024)
 92 #define AR_BUFFERS_MIN  DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
 93 /* we need at least two pages for proper list management */
 94 #define AR_BUFFERS      (AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)
 95 
 96 #define MAX_ASYNC_PAYLOAD       4096
 97 #define MAX_AR_PACKET_SIZE      (16 + MAX_ASYNC_PAYLOAD + 4)
 98 #define AR_WRAPAROUND_PAGES     DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)
 99 
100 struct ar_context {
101         struct fw_ohci *ohci;
102         struct page *pages[AR_BUFFERS];
103         void *buffer;
104         struct descriptor *descriptors;
105         dma_addr_t descriptors_bus;
106         void *pointer;
107         unsigned int last_buffer_index;
108         u32 regs;
109         struct tasklet_struct tasklet;
110 };
111 
112 struct context;
113 
114 typedef int (*descriptor_callback_t)(struct context *ctx,
115                                      struct descriptor *d,
116                                      struct descriptor *last);
117 
118 /*
119  * A buffer that contains a block of DMA-able coherent memory used for
120  * storing a portion of a DMA descriptor program.
121  */
122 struct descriptor_buffer {
123         struct list_head list;
124         dma_addr_t buffer_bus;
125         size_t buffer_size;
126         size_t used;
127         struct descriptor buffer[0];
128 };
129 
130 struct context {
131         struct fw_ohci *ohci;
132         u32 regs;
133         int total_allocation;
134         u32 current_bus;
135         bool running;
136         bool flushing;
137 
138         /*
139          * List of page-sized buffers for storing DMA descriptors.
140          * Head of list contains buffers in use and tail of list contains
141          * free buffers.
142          */
143         struct list_head buffer_list;
144 
145         /*
146          * Pointer to a buffer inside buffer_list that contains the tail
147          * end of the current DMA program.
148          */
149         struct descriptor_buffer *buffer_tail;
150 
151         /*
152          * The descriptor containing the branch address of the first
153          * descriptor that has not yet been filled by the device.
154          */
155         struct descriptor *last;
156 
157         /*
158          * The last descriptor block in the DMA program. It contains the branch
159          * address that must be updated upon appending a new descriptor.
160          */
161         struct descriptor *prev;
162         int prev_z;
163 
164         descriptor_callback_t callback;
165 
166         struct tasklet_struct tasklet;
167 };
168 
169 #define IT_HEADER_SY(v)          ((v) <<  0)
170 #define IT_HEADER_TCODE(v)       ((v) <<  4)
171 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
172 #define IT_HEADER_TAG(v)         ((v) << 14)
173 #define IT_HEADER_SPEED(v)       ((v) << 16)
174 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
175 
176 struct iso_context {
177         struct fw_iso_context base;
178         struct context context;
179         void *header;
180         size_t header_length;
181         unsigned long flushing_completions;
182         u32 mc_buffer_bus;
183         u16 mc_completed;
184         u16 last_timestamp;
185         u8 sync;
186         u8 tags;
187 };
188 
189 #define CONFIG_ROM_SIZE 1024
190 
191 struct fw_ohci {
192         struct fw_card card;
193 
194         __iomem char *registers;
195         int node_id;
196         int generation;
197         int request_generation; /* for timestamping incoming requests */
198         unsigned quirks;
199         unsigned int pri_req_max;
200         u32 bus_time;
201         bool bus_time_running;
202         bool is_root;
203         bool csr_state_setclear_abdicate;
204         int n_ir;
205         int n_it;
206         /*
207          * Spinlock for accessing fw_ohci data.  Never call out of
208          * this driver with this lock held.
209          */
210         spinlock_t lock;
211 
212         struct mutex phy_reg_mutex;
213 
214         void *misc_buffer;
215         dma_addr_t misc_buffer_bus;
216 
217         struct ar_context ar_request_ctx;
218         struct ar_context ar_response_ctx;
219         struct context at_request_ctx;
220         struct context at_response_ctx;
221 
222         u32 it_context_support;
223         u32 it_context_mask;     /* unoccupied IT contexts */
224         struct iso_context *it_context_list;
225         u64 ir_context_channels; /* unoccupied channels */
226         u32 ir_context_support;
227         u32 ir_context_mask;     /* unoccupied IR contexts */
228         struct iso_context *ir_context_list;
229         u64 mc_channels; /* channels in use by the multichannel IR context */
230         bool mc_allocated;
231 
232         __be32    *config_rom;
233         dma_addr_t config_rom_bus;
234         __be32    *next_config_rom;
235         dma_addr_t next_config_rom_bus;
236         __be32     next_header;
237 
238         __le32    *self_id;
239         dma_addr_t self_id_bus;
240         struct work_struct bus_reset_work;
241 
242         u32 self_id_buffer[512];
243 };
244 
245 static struct workqueue_struct *selfid_workqueue;
246 
247 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
248 {
249         return container_of(card, struct fw_ohci, card);
250 }
251 
252 #define IT_CONTEXT_CYCLE_MATCH_ENABLE   0x80000000
253 #define IR_CONTEXT_BUFFER_FILL          0x80000000
254 #define IR_CONTEXT_ISOCH_HEADER         0x40000000
255 #define IR_CONTEXT_CYCLE_MATCH_ENABLE   0x20000000
256 #define IR_CONTEXT_MULTI_CHANNEL_MODE   0x10000000
257 #define IR_CONTEXT_DUAL_BUFFER_MODE     0x08000000
258 
259 #define CONTEXT_RUN     0x8000
260 #define CONTEXT_WAKE    0x1000
261 #define CONTEXT_DEAD    0x0800
262 #define CONTEXT_ACTIVE  0x0400
263 
264 #define OHCI1394_MAX_AT_REQ_RETRIES     0xf
265 #define OHCI1394_MAX_AT_RESP_RETRIES    0x2
266 #define OHCI1394_MAX_PHYS_RESP_RETRIES  0x8
267 
268 #define OHCI1394_REGISTER_SIZE          0x800
269 #define OHCI1394_PCI_HCI_Control        0x40
270 #define SELF_ID_BUF_SIZE                0x800
271 #define OHCI_TCODE_PHY_PACKET           0x0e
272 #define OHCI_VERSION_1_1                0x010010
273 
274 static char ohci_driver_name[] = KBUILD_MODNAME;
275 
276 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS  0x11bd
277 #define PCI_DEVICE_ID_AGERE_FW643       0x5901
278 #define PCI_DEVICE_ID_CREATIVE_SB1394   0x4001
279 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW 0x2380
280 #define PCI_DEVICE_ID_TI_TSB12LV22      0x8009
281 #define PCI_DEVICE_ID_TI_TSB12LV26      0x8020
282 #define PCI_DEVICE_ID_TI_TSB82AA2       0x8025
283 #define PCI_DEVICE_ID_VIA_VT630X        0x3044
284 #define PCI_REV_ID_VIA_VT6306           0x46
285 #define PCI_DEVICE_ID_VIA_VT6315        0x3403
286 
287 #define QUIRK_CYCLE_TIMER               0x1
288 #define QUIRK_RESET_PACKET              0x2
289 #define QUIRK_BE_HEADERS                0x4
290 #define QUIRK_NO_1394A                  0x8
291 #define QUIRK_NO_MSI                    0x10
292 #define QUIRK_TI_SLLZ059                0x20
293 #define QUIRK_IR_WAKE                   0x40
294 
295 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
296 static const struct {
297         unsigned short vendor, device, revision, flags;
298 } ohci_quirks[] = {
299         {PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
300                 QUIRK_CYCLE_TIMER},
301 
302         {PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
303                 QUIRK_BE_HEADERS},
304 
305         {PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
306                 QUIRK_NO_MSI},
307 
308         {PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
309                 QUIRK_RESET_PACKET},
310 
311         {PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
312                 QUIRK_NO_MSI},
313 
314         {PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
315                 QUIRK_CYCLE_TIMER},
316 
317         {PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
318                 QUIRK_NO_MSI},
319 
320         {PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
321                 QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
322 
323         {PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
324                 QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
325 
326         {PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
327                 QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
328 
329         {PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
330                 QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},
331 
332         {PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
333                 QUIRK_RESET_PACKET},
334 
335         {PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT630X, PCI_REV_ID_VIA_VT6306,
336                 QUIRK_CYCLE_TIMER | QUIRK_IR_WAKE},
337 
338         {PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, 0,
339                 QUIRK_CYCLE_TIMER /* FIXME: necessary? */ | QUIRK_NO_MSI},
340 
341         {PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, PCI_ANY_ID,
342                 QUIRK_NO_MSI},
343 
344         {PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
345                 QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
346 };
347 
348 /* This overrides anything that was found in ohci_quirks[]. */
349 static int param_quirks;
350 module_param_named(quirks, param_quirks, int, 0644);
351 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
352         ", nonatomic cycle timer = "    __stringify(QUIRK_CYCLE_TIMER)
353         ", reset packet generation = "  __stringify(QUIRK_RESET_PACKET)
354         ", AR/selfID endianness = "     __stringify(QUIRK_BE_HEADERS)
355         ", no 1394a enhancements = "    __stringify(QUIRK_NO_1394A)
356         ", disable MSI = "              __stringify(QUIRK_NO_MSI)
357         ", TI SLLZ059 erratum = "       __stringify(QUIRK_TI_SLLZ059)
358         ", IR wake unreliable = "       __stringify(QUIRK_IR_WAKE)
359         ")");
360 
361 #define OHCI_PARAM_DEBUG_AT_AR          1
362 #define OHCI_PARAM_DEBUG_SELFIDS        2
363 #define OHCI_PARAM_DEBUG_IRQS           4
364 #define OHCI_PARAM_DEBUG_BUSRESETS      8 /* only effective before chip init */
365 
366 static int param_debug;
367 module_param_named(debug, param_debug, int, 0644);
368 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
369         ", AT/AR events = "     __stringify(OHCI_PARAM_DEBUG_AT_AR)
370         ", self-IDs = "         __stringify(OHCI_PARAM_DEBUG_SELFIDS)
371         ", IRQs = "             __stringify(OHCI_PARAM_DEBUG_IRQS)
372         ", busReset events = "  __stringify(OHCI_PARAM_DEBUG_BUSRESETS)
373         ", or a combination, or all = -1)");
374 
375 static bool param_remote_dma;
376 module_param_named(remote_dma, param_remote_dma, bool, 0444);
377 MODULE_PARM_DESC(remote_dma, "Enable unfiltered remote DMA (default = N)");
378 
379 static void log_irqs(struct fw_ohci *ohci, u32 evt)
380 {
381         if (likely(!(param_debug &
382                         (OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
383                 return;
384 
385         if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
386             !(evt & OHCI1394_busReset))
387                 return;
388 
389         ohci_notice(ohci, "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
390             evt & OHCI1394_selfIDComplete       ? " selfID"             : "",
391             evt & OHCI1394_RQPkt                ? " AR_req"             : "",
392             evt & OHCI1394_RSPkt                ? " AR_resp"            : "",
393             evt & OHCI1394_reqTxComplete        ? " AT_req"             : "",
394             evt & OHCI1394_respTxComplete       ? " AT_resp"            : "",
395             evt & OHCI1394_isochRx              ? " IR"                 : "",
396             evt & OHCI1394_isochTx              ? " IT"                 : "",
397             evt & OHCI1394_postedWriteErr       ? " postedWriteErr"     : "",
398             evt & OHCI1394_cycleTooLong         ? " cycleTooLong"       : "",
399             evt & OHCI1394_cycle64Seconds       ? " cycle64Seconds"     : "",
400             evt & OHCI1394_cycleInconsistent    ? " cycleInconsistent"  : "",
401             evt & OHCI1394_regAccessFail        ? " regAccessFail"      : "",
402             evt & OHCI1394_unrecoverableError   ? " unrecoverableError" : "",
403             evt & OHCI1394_busReset             ? " busReset"           : "",
404             evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
405                     OHCI1394_RSPkt | OHCI1394_reqTxComplete |
406                     OHCI1394_respTxComplete | OHCI1394_isochRx |
407                     OHCI1394_isochTx | OHCI1394_postedWriteErr |
408                     OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
409                     OHCI1394_cycleInconsistent |
410                     OHCI1394_regAccessFail | OHCI1394_busReset)
411                                                 ? " ?"                  : "");
412 }
413 
414 static const char *speed[] = {
415         [0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
416 };
417 static const char *power[] = {
418         [0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
419         [4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
420 };
421 static const char port[] = { '.', '-', 'p', 'c', };
422 
423 static char _p(u32 *s, int shift)
424 {
425         return port[*s >> shift & 3];
426 }
427 
428 static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
429 {
430         u32 *s;
431 
432         if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
433                 return;
434 
435         ohci_notice(ohci, "%d selfIDs, generation %d, local node ID %04x\n",
436                     self_id_count, generation, ohci->node_id);
437 
438         for (s = ohci->self_id_buffer; self_id_count--; ++s)
439                 if ((*s & 1 << 23) == 0)
440                         ohci_notice(ohci,
441                             "selfID 0: %08x, phy %d [%c%c%c] %s gc=%d %s %s%s%s\n",
442                             *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
443                             speed[*s >> 14 & 3], *s >> 16 & 63,
444                             power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
445                             *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
446                 else
447                         ohci_notice(ohci,
448                             "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
449                             *s, *s >> 24 & 63,
450                             _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
451                             _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
452 }
453 
454 static const char *evts[] = {
455         [0x00] = "evt_no_status",       [0x01] = "-reserved-",
456         [0x02] = "evt_long_packet",     [0x03] = "evt_missing_ack",
457         [0x04] = "evt_underrun",        [0x05] = "evt_overrun",
458         [0x06] = "evt_descriptor_read", [0x07] = "evt_data_read",
459         [0x08] = "evt_data_write",      [0x09] = "evt_bus_reset",
460         [0x0a] = "evt_timeout",         [0x0b] = "evt_tcode_err",
461         [0x0c] = "-reserved-",          [0x0d] = "-reserved-",
462         [0x0e] = "evt_unknown",         [0x0f] = "evt_flushed",
463         [0x10] = "-reserved-",          [0x11] = "ack_complete",
464         [0x12] = "ack_pending ",        [0x13] = "-reserved-",
465         [0x14] = "ack_busy_X",          [0x15] = "ack_busy_A",
466         [0x16] = "ack_busy_B",          [0x17] = "-reserved-",
467         [0x18] = "-reserved-",          [0x19] = "-reserved-",
468         [0x1a] = "-reserved-",          [0x1b] = "ack_tardy",
469         [0x1c] = "-reserved-",          [0x1d] = "ack_data_error",
470         [0x1e] = "ack_type_error",      [0x1f] = "-reserved-",
471         [0x20] = "pending/cancelled",
472 };
473 static const char *tcodes[] = {
474         [0x0] = "QW req",               [0x1] = "BW req",
475         [0x2] = "W resp",               [0x3] = "-reserved-",
476         [0x4] = "QR req",               [0x5] = "BR req",
477         [0x6] = "QR resp",              [0x7] = "BR resp",
478         [0x8] = "cycle start",          [0x9] = "Lk req",
479         [0xa] = "async stream packet",  [0xb] = "Lk resp",
480         [0xc] = "-reserved-",           [0xd] = "-reserved-",
481         [0xe] = "link internal",        [0xf] = "-reserved-",
482 };
483 
484 static void log_ar_at_event(struct fw_ohci *ohci,
485                             char dir, int speed, u32 *header, int evt)
486 {
487         int tcode = header[0] >> 4 & 0xf;
488         char specific[12];
489 
490         if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
491                 return;
492 
493         if (unlikely(evt >= ARRAY_SIZE(evts)))
494                         evt = 0x1f;
495 
496         if (evt == OHCI1394_evt_bus_reset) {
497                 ohci_notice(ohci, "A%c evt_bus_reset, generation %d\n",
498                             dir, (header[2] >> 16) & 0xff);
499                 return;
500         }
501 
502         switch (tcode) {
503         case 0x0: case 0x6: case 0x8:
504                 snprintf(specific, sizeof(specific), " = %08x",
505                          be32_to_cpu((__force __be32)header[3]));
506                 break;
507         case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
508                 snprintf(specific, sizeof(specific), " %x,%x",
509                          header[3] >> 16, header[3] & 0xffff);
510                 break;
511         default:
512                 specific[0] = '\0';
513         }
514 
515         switch (tcode) {
516         case 0xa:
517                 ohci_notice(ohci, "A%c %s, %s\n",
518                             dir, evts[evt], tcodes[tcode]);
519                 break;
520         case 0xe:
521                 ohci_notice(ohci, "A%c %s, PHY %08x %08x\n",
522                             dir, evts[evt], header[1], header[2]);
523                 break;
524         case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
525                 ohci_notice(ohci,
526                             "A%c spd %x tl %02x, %04x -> %04x, %s, %s, %04x%08x%s\n",
527                             dir, speed, header[0] >> 10 & 0x3f,
528                             header[1] >> 16, header[0] >> 16, evts[evt],
529                             tcodes[tcode], header[1] & 0xffff, header[2], specific);
530                 break;
531         default:
532                 ohci_notice(ohci,
533                             "A%c spd %x tl %02x, %04x -> %04x, %s, %s%s\n",
534                             dir, speed, header[0] >> 10 & 0x3f,
535                             header[1] >> 16, header[0] >> 16, evts[evt],
536                             tcodes[tcode], specific);
537         }
538 }
539 
540 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
541 {
542         writel(data, ohci->registers + offset);
543 }
544 
545 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
546 {
547         return readl(ohci->registers + offset);
548 }
549 
550 static inline void flush_writes(const struct fw_ohci *ohci)
551 {
552         /* Do a dummy read to flush writes. */
553         reg_read(ohci, OHCI1394_Version);
554 }
555 
556 /*
557  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
558  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
559  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
560  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
561  */
562 static int read_phy_reg(struct fw_ohci *ohci, int addr)
563 {
564         u32 val;
565         int i;
566 
567         reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
568         for (i = 0; i < 3 + 100; i++) {
569                 val = reg_read(ohci, OHCI1394_PhyControl);
570                 if (!~val)
571                         return -ENODEV; /* Card was ejected. */
572 
573                 if (val & OHCI1394_PhyControl_ReadDone)
574                         return OHCI1394_PhyControl_ReadData(val);
575 
576                 /*
577                  * Try a few times without waiting.  Sleeping is necessary
578                  * only when the link/PHY interface is busy.
579                  */
580                 if (i >= 3)
581                         msleep(1);
582         }
583         ohci_err(ohci, "failed to read phy reg %d\n", addr);
584         dump_stack();
585 
586         return -EBUSY;
587 }
588 
589 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
590 {
591         int i;
592 
593         reg_write(ohci, OHCI1394_PhyControl,
594                   OHCI1394_PhyControl_Write(addr, val));
595         for (i = 0; i < 3 + 100; i++) {
596                 val = reg_read(ohci, OHCI1394_PhyControl);
597                 if (!~val)
598                         return -ENODEV; /* Card was ejected. */
599 
600                 if (!(val & OHCI1394_PhyControl_WritePending))
601                         return 0;
602 
603                 if (i >= 3)
604                         msleep(1);
605         }
606         ohci_err(ohci, "failed to write phy reg %d, val %u\n", addr, val);
607         dump_stack();
608 
609         return -EBUSY;
610 }
611 
612 static int update_phy_reg(struct fw_ohci *ohci, int addr,
613                           int clear_bits, int set_bits)
614 {
615         int ret = read_phy_reg(ohci, addr);
616         if (ret < 0)
617                 return ret;
618 
619         /*
620          * The interrupt status bits are cleared by writing a one bit.
621          * Avoid clearing them unless explicitly requested in set_bits.
622          */
623         if (addr == 5)
624                 clear_bits |= PHY_INT_STATUS_BITS;
625 
626         return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
627 }
628 
629 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
630 {
631         int ret;
632 
633         ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
634         if (ret < 0)
635                 return ret;
636 
637         return read_phy_reg(ohci, addr);
638 }
639 
640 static int ohci_read_phy_reg(struct fw_card *card, int addr)
641 {
642         struct fw_ohci *ohci = fw_ohci(card);
643         int ret;
644 
645         mutex_lock(&ohci->phy_reg_mutex);
646         ret = read_phy_reg(ohci, addr);
647         mutex_unlock(&ohci->phy_reg_mutex);
648 
649         return ret;
650 }
651 
652 static int ohci_update_phy_reg(struct fw_card *card, int addr,
653                                int clear_bits, int set_bits)
654 {
655         struct fw_ohci *ohci = fw_ohci(card);
656         int ret;
657 
658         mutex_lock(&ohci->phy_reg_mutex);
659         ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
660         mutex_unlock(&ohci->phy_reg_mutex);
661 
662         return ret;
663 }
664 
665 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
666 {
667         return page_private(ctx->pages[i]);
668 }
669 
670 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
671 {
672         struct descriptor *d;
673 
674         d = &ctx->descriptors[index];
675         d->branch_address  &= cpu_to_le32(~0xf);
676         d->res_count       =  cpu_to_le16(PAGE_SIZE);
677         d->transfer_status =  0;
678 
679         wmb(); /* finish init of new descriptors before branch_address update */
680         d = &ctx->descriptors[ctx->last_buffer_index];
681         d->branch_address  |= cpu_to_le32(1);
682 
683         ctx->last_buffer_index = index;
684 
685         reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
686 }
687 
688 static void ar_context_release(struct ar_context *ctx)
689 {
690         unsigned int i;
691 
692         if (ctx->buffer)
693                 vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
694 
695         for (i = 0; i < AR_BUFFERS; i++)
696                 if (ctx->pages[i]) {
697                         dma_unmap_page(ctx->ohci->card.device,
698                                        ar_buffer_bus(ctx, i),
699                                        PAGE_SIZE, DMA_FROM_DEVICE);
700                         __free_page(ctx->pages[i]);
701                 }
702 }
703 
704 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
705 {
706         struct fw_ohci *ohci = ctx->ohci;
707 
708         if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
709                 reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
710                 flush_writes(ohci);
711 
712                 ohci_err(ohci, "AR error: %s; DMA stopped\n", error_msg);
713         }
714         /* FIXME: restart? */
715 }
716 
717 static inline unsigned int ar_next_buffer_index(unsigned int index)
718 {
719         return (index + 1) % AR_BUFFERS;
720 }
721 
722 static inline unsigned int ar_prev_buffer_index(unsigned int index)
723 {
724         return (index - 1 + AR_BUFFERS) % AR_BUFFERS;
725 }
726 
727 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
728 {
729         return ar_next_buffer_index(ctx->last_buffer_index);
730 }
731 
732 /*
733  * We search for the buffer that contains the last AR packet DMA data written
734  * by the controller.
735  */
736 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
737                                                  unsigned int *buffer_offset)
738 {
739         unsigned int i, next_i, last = ctx->last_buffer_index;
740         __le16 res_count, next_res_count;
741 
742         i = ar_first_buffer_index(ctx);
743         res_count = ACCESS_ONCE(ctx->descriptors[i].res_count);
744 
745         /* A buffer that is not yet completely filled must be the last one. */
746         while (i != last && res_count == 0) {
747 
748                 /* Peek at the next descriptor. */
749                 next_i = ar_next_buffer_index(i);
750                 rmb(); /* read descriptors in order */
751                 next_res_count = ACCESS_ONCE(
752                                 ctx->descriptors[next_i].res_count);
753                 /*
754                  * If the next descriptor is still empty, we must stop at this
755                  * descriptor.
756                  */
757                 if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
758                         /*
759                          * The exception is when the DMA data for one packet is
760                          * split over three buffers; in this case, the middle
761                          * buffer's descriptor might be never updated by the
762                          * controller and look still empty, and we have to peek
763                          * at the third one.
764                          */
765                         if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
766                                 next_i = ar_next_buffer_index(next_i);
767                                 rmb();
768                                 next_res_count = ACCESS_ONCE(
769                                         ctx->descriptors[next_i].res_count);
770                                 if (next_res_count != cpu_to_le16(PAGE_SIZE))
771                                         goto next_buffer_is_active;
772                         }
773 
774                         break;
775                 }
776 
777 next_buffer_is_active:
778                 i = next_i;
779                 res_count = next_res_count;
780         }
781 
782         rmb(); /* read res_count before the DMA data */
783 
784         *buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
785         if (*buffer_offset > PAGE_SIZE) {
786                 *buffer_offset = 0;
787                 ar_context_abort(ctx, "corrupted descriptor");
788         }
789 
790         return i;
791 }
792 
793 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
794                                     unsigned int end_buffer_index,
795                                     unsigned int end_buffer_offset)
796 {
797         unsigned int i;
798 
799         i = ar_first_buffer_index(ctx);
800         while (i != end_buffer_index) {
801                 dma_sync_single_for_cpu(ctx->ohci->card.device,
802                                         ar_buffer_bus(ctx, i),
803                                         PAGE_SIZE, DMA_FROM_DEVICE);
804                 i = ar_next_buffer_index(i);
805         }
806         if (end_buffer_offset > 0)
807                 dma_sync_single_for_cpu(ctx->ohci->card.device,
808                                         ar_buffer_bus(ctx, i),
809                                         end_buffer_offset, DMA_FROM_DEVICE);
810 }
811 
812 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
813 #define cond_le32_to_cpu(v) \
814         (ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
815 #else
816 #define cond_le32_to_cpu(v) le32_to_cpu(v)
817 #endif
818 
819 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
820 {
821         struct fw_ohci *ohci = ctx->ohci;
822         struct fw_packet p;
823         u32 status, length, tcode;
824         int evt;
825 
826         p.header[0] = cond_le32_to_cpu(buffer[0]);
827         p.header[1] = cond_le32_to_cpu(buffer[1]);
828         p.header[2] = cond_le32_to_cpu(buffer[2]);
829 
830         tcode = (p.header[0] >> 4) & 0x0f;
831         switch (tcode) {
832         case TCODE_WRITE_QUADLET_REQUEST:
833         case TCODE_READ_QUADLET_RESPONSE:
834                 p.header[3] = (__force __u32) buffer[3];
835                 p.header_length = 16;
836                 p.payload_length = 0;
837                 break;
838 
839         case TCODE_READ_BLOCK_REQUEST :
840                 p.header[3] = cond_le32_to_cpu(buffer[3]);
841                 p.header_length = 16;
842                 p.payload_length = 0;
843                 break;
844 
845         case TCODE_WRITE_BLOCK_REQUEST:
846         case TCODE_READ_BLOCK_RESPONSE:
847         case TCODE_LOCK_REQUEST:
848         case TCODE_LOCK_RESPONSE:
849                 p.header[3] = cond_le32_to_cpu(buffer[3]);
850                 p.header_length = 16;
851                 p.payload_length = p.header[3] >> 16;
852                 if (p.payload_length > MAX_ASYNC_PAYLOAD) {
853                         ar_context_abort(ctx, "invalid packet length");
854                         return NULL;
855                 }
856                 break;
857 
858         case TCODE_WRITE_RESPONSE:
859         case TCODE_READ_QUADLET_REQUEST:
860         case OHCI_TCODE_PHY_PACKET:
861                 p.header_length = 12;
862                 p.payload_length = 0;
863                 break;
864 
865         default:
866                 ar_context_abort(ctx, "invalid tcode");
867                 return NULL;
868         }
869 
870         p.payload = (void *) buffer + p.header_length;
871 
872         /* FIXME: What to do about evt_* errors? */
873         length = (p.header_length + p.payload_length + 3) / 4;
874         status = cond_le32_to_cpu(buffer[length]);
875         evt    = (status >> 16) & 0x1f;
876 
877         p.ack        = evt - 16;
878         p.speed      = (status >> 21) & 0x7;
879         p.timestamp  = status & 0xffff;
880         p.generation = ohci->request_generation;
881 
882         log_ar_at_event(ohci, 'R', p.speed, p.header, evt);
883 
884         /*
885          * Several controllers, notably from NEC and VIA, forget to
886          * write ack_complete status at PHY packet reception.
887          */
888         if (evt == OHCI1394_evt_no_status &&
889             (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
890                 p.ack = ACK_COMPLETE;
891 
892         /*
893          * The OHCI bus reset handler synthesizes a PHY packet with
894          * the new generation number when a bus reset happens (see
895          * section 8.4.2.3).  This helps us determine when a request
896          * was received and make sure we send the response in the same
897          * generation.  We only need this for requests; for responses
898          * we use the unique tlabel for finding the matching
899          * request.
900          *
901          * Alas some chips sometimes emit bus reset packets with a
902          * wrong generation.  We set the correct generation for these
903          * at a slightly incorrect time (in bus_reset_work).
904          */
905         if (evt == OHCI1394_evt_bus_reset) {
906                 if (!(ohci->quirks & QUIRK_RESET_PACKET))
907                         ohci->request_generation = (p.header[2] >> 16) & 0xff;
908         } else if (ctx == &ohci->ar_request_ctx) {
909                 fw_core_handle_request(&ohci->card, &p);
910         } else {
911                 fw_core_handle_response(&ohci->card, &p);
912         }
913 
914         return buffer + length + 1;
915 }
916 
917 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
918 {
919         void *next;
920 
921         while (p < end) {
922                 next = handle_ar_packet(ctx, p);
923                 if (!next)
924                         return p;
925                 p = next;
926         }
927 
928         return p;
929 }
930 
931 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
932 {
933         unsigned int i;
934 
935         i = ar_first_buffer_index(ctx);
936         while (i != end_buffer) {
937                 dma_sync_single_for_device(ctx->ohci->card.device,
938                                            ar_buffer_bus(ctx, i),
939                                            PAGE_SIZE, DMA_FROM_DEVICE);
940                 ar_context_link_page(ctx, i);
941                 i = ar_next_buffer_index(i);
942         }
943 }
944 
945 static void ar_context_tasklet(unsigned long data)
946 {
947         struct ar_context *ctx = (struct ar_context *)data;
948         unsigned int end_buffer_index, end_buffer_offset;
949         void *p, *end;
950 
951         p = ctx->pointer;
952         if (!p)
953                 return;
954 
955         end_buffer_index = ar_search_last_active_buffer(ctx,
956                                                         &end_buffer_offset);
957         ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
958         end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
959 
960         if (end_buffer_index < ar_first_buffer_index(ctx)) {
961                 /*
962                  * The filled part of the overall buffer wraps around; handle
963                  * all packets up to the buffer end here.  If the last packet
964                  * wraps around, its tail will be visible after the buffer end
965                  * because the buffer start pages are mapped there again.
966                  */
967                 void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
968                 p = handle_ar_packets(ctx, p, buffer_end);
969                 if (p < buffer_end)
970                         goto error;
971                 /* adjust p to point back into the actual buffer */
972                 p -= AR_BUFFERS * PAGE_SIZE;
973         }
974 
975         p = handle_ar_packets(ctx, p, end);
976         if (p != end) {
977                 if (p > end)
978                         ar_context_abort(ctx, "inconsistent descriptor");
979                 goto error;
980         }
981 
982         ctx->pointer = p;
983         ar_recycle_buffers(ctx, end_buffer_index);
984 
985         return;
986 
987 error:
988         ctx->pointer = NULL;
989 }
990 
991 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
992                            unsigned int descriptors_offset, u32 regs)
993 {
994         unsigned int i;
995         dma_addr_t dma_addr;
996         struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
997         struct descriptor *d;
998 
999         ctx->regs        = regs;
1000         ctx->ohci        = ohci;
1001         tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
1002 
1003         for (i = 0; i < AR_BUFFERS; i++) {
1004                 ctx->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32);
1005                 if (!ctx->pages[i])
1006                         goto out_of_memory;
1007                 dma_addr = dma_map_page(ohci->card.device, ctx->pages[i],
1008                                         0, PAGE_SIZE, DMA_FROM_DEVICE);
1009                 if (dma_mapping_error(ohci->card.device, dma_addr)) {
1010                         __free_page(ctx->pages[i]);
1011                         ctx->pages[i] = NULL;
1012                         goto out_of_memory;
1013                 }
1014                 set_page_private(ctx->pages[i], dma_addr);
1015         }
1016 
1017         for (i = 0; i < AR_BUFFERS; i++)
1018                 pages[i]              = ctx->pages[i];
1019         for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
1020                 pages[AR_BUFFERS + i] = ctx->pages[i];
1021         ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
1022                                  -1, PAGE_KERNEL);
1023         if (!ctx->buffer)
1024                 goto out_of_memory;
1025 
1026         ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
1027         ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
1028 
1029         for (i = 0; i < AR_BUFFERS; i++) {
1030                 d = &ctx->descriptors[i];
1031                 d->req_count      = cpu_to_le16(PAGE_SIZE);
1032                 d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
1033                                                 DESCRIPTOR_STATUS |
1034                                                 DESCRIPTOR_BRANCH_ALWAYS);
1035                 d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
1036                 d->branch_address = cpu_to_le32(ctx->descriptors_bus +
1037                         ar_next_buffer_index(i) * sizeof(struct descriptor));
1038         }
1039 
1040         return 0;
1041 
1042 out_of_memory:
1043         ar_context_release(ctx);
1044 
1045         return -ENOMEM;
1046 }
1047 
1048 static void ar_context_run(struct ar_context *ctx)
1049 {
1050         unsigned int i;
1051 
1052         for (i = 0; i < AR_BUFFERS; i++)
1053                 ar_context_link_page(ctx, i);
1054 
1055         ctx->pointer = ctx->buffer;
1056 
1057         reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1058         reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1059 }
1060 
1061 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1062 {
1063         __le16 branch;
1064 
1065         branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1066 
1067         /* figure out which descriptor the branch address goes in */
1068         if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1069                 return d;
1070         else
1071                 return d + z - 1;
1072 }
1073 
1074 static void context_tasklet(unsigned long data)
1075 {
1076         struct context *ctx = (struct context *) data;
1077         struct descriptor *d, *last;
1078         u32 address;
1079         int z;
1080         struct descriptor_buffer *desc;
1081 
1082         desc = list_entry(ctx->buffer_list.next,
1083                         struct descriptor_buffer, list);
1084         last = ctx->last;
1085         while (last->branch_address != 0) {
1086                 struct descriptor_buffer *old_desc = desc;
1087                 address = le32_to_cpu(last->branch_address);
1088                 z = address & 0xf;
1089                 address &= ~0xf;
1090                 ctx->current_bus = address;
1091 
1092                 /* If the branch address points to a buffer outside of the
1093                  * current buffer, advance to the next buffer. */
1094                 if (address < desc->buffer_bus ||
1095                                 address >= desc->buffer_bus + desc->used)
1096                         desc = list_entry(desc->list.next,
1097                                         struct descriptor_buffer, list);
1098                 d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1099                 last = find_branch_descriptor(d, z);
1100 
1101                 if (!ctx->callback(ctx, d, last))
1102                         break;
1103 
1104                 if (old_desc != desc) {
1105                         /* If we've advanced to the next buffer, move the
1106                          * previous buffer to the free list. */
1107                         unsigned long flags;
1108                         old_desc->used = 0;
1109                         spin_lock_irqsave(&ctx->ohci->lock, flags);
1110                         list_move_tail(&old_desc->list, &ctx->buffer_list);
1111                         spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1112                 }
1113                 ctx->last = last;
1114         }
1115 }
1116 
1117 /*
1118  * Allocate a new buffer and add it to the list of free buffers for this
1119  * context.  Must be called with ohci->lock held.
1120  */
1121 static int context_add_buffer(struct context *ctx)
1122 {
1123         struct descriptor_buffer *desc;
1124         dma_addr_t uninitialized_var(bus_addr);
1125         int offset;
1126 
1127         /*
1128          * 16MB of descriptors should be far more than enough for any DMA
1129          * program.  This will catch run-away userspace or DoS attacks.
1130          */
1131         if (ctx->total_allocation >= 16*1024*1024)
1132                 return -ENOMEM;
1133 
1134         desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1135                         &bus_addr, GFP_ATOMIC);
1136         if (!desc)
1137                 return -ENOMEM;
1138 
1139         offset = (void *)&desc->buffer - (void *)desc;
1140         desc->buffer_size = PAGE_SIZE - offset;
1141         desc->buffer_bus = bus_addr + offset;
1142         desc->used = 0;
1143 
1144         list_add_tail(&desc->list, &ctx->buffer_list);
1145         ctx->total_allocation += PAGE_SIZE;
1146 
1147         return 0;
1148 }
1149 
1150 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1151                         u32 regs, descriptor_callback_t callback)
1152 {
1153         ctx->ohci = ohci;
1154         ctx->regs = regs;
1155         ctx->total_allocation = 0;
1156 
1157         INIT_LIST_HEAD(&ctx->buffer_list);
1158         if (context_add_buffer(ctx) < 0)
1159                 return -ENOMEM;
1160 
1161         ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1162                         struct descriptor_buffer, list);
1163 
1164         tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1165         ctx->callback = callback;
1166 
1167         /*
1168          * We put a dummy descriptor in the buffer that has a NULL
1169          * branch address and looks like it's been sent.  That way we
1170          * have a descriptor to append DMA programs to.
1171          */
1172         memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1173         ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1174         ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1175         ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1176         ctx->last = ctx->buffer_tail->buffer;
1177         ctx->prev = ctx->buffer_tail->buffer;
1178         ctx->prev_z = 1;
1179 
1180         return 0;
1181 }
1182 
1183 static void context_release(struct context *ctx)
1184 {
1185         struct fw_card *card = &ctx->ohci->card;
1186         struct descriptor_buffer *desc, *tmp;
1187 
1188         list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1189                 dma_free_coherent(card->device, PAGE_SIZE, desc,
1190                         desc->buffer_bus -
1191                         ((void *)&desc->buffer - (void *)desc));
1192 }
1193 
1194 /* Must be called with ohci->lock held */
1195 static struct descriptor *context_get_descriptors(struct context *ctx,
1196                                                   int z, dma_addr_t *d_bus)
1197 {
1198         struct descriptor *d = NULL;
1199         struct descriptor_buffer *desc = ctx->buffer_tail;
1200 
1201         if (z * sizeof(*d) > desc->buffer_size)
1202                 return NULL;
1203 
1204         if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1205                 /* No room for the descriptor in this buffer, so advance to the
1206                  * next one. */
1207 
1208                 if (desc->list.next == &ctx->buffer_list) {
1209                         /* If there is no free buffer next in the list,
1210                          * allocate one. */
1211                         if (context_add_buffer(ctx) < 0)
1212                                 return NULL;
1213                 }
1214                 desc = list_entry(desc->list.next,
1215                                 struct descriptor_buffer, list);
1216                 ctx->buffer_tail = desc;
1217         }
1218 
1219         d = desc->buffer + desc->used / sizeof(*d);
1220         memset(d, 0, z * sizeof(*d));
1221         *d_bus = desc->buffer_bus + desc->used;
1222 
1223         return d;
1224 }
1225 
1226 static void context_run(struct context *ctx, u32 extra)
1227 {
1228         struct fw_ohci *ohci = ctx->ohci;
1229 
1230         reg_write(ohci, COMMAND_PTR(ctx->regs),
1231                   le32_to_cpu(ctx->last->branch_address));
1232         reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1233         reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1234         ctx->running = true;
1235         flush_writes(ohci);
1236 }
1237 
1238 static void context_append(struct context *ctx,
1239                            struct descriptor *d, int z, int extra)
1240 {
1241         dma_addr_t d_bus;
1242         struct descriptor_buffer *desc = ctx->buffer_tail;
1243         struct descriptor *d_branch;
1244 
1245         d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1246 
1247         desc->used += (z + extra) * sizeof(*d);
1248 
1249         wmb(); /* finish init of new descriptors before branch_address update */
1250 
1251         d_branch = find_branch_descriptor(ctx->prev, ctx->prev_z);
1252         d_branch->branch_address = cpu_to_le32(d_bus | z);
1253 
1254         /*
1255          * VT6306 incorrectly checks only the single descriptor at the
1256          * CommandPtr when the wake bit is written, so if it's a
1257          * multi-descriptor block starting with an INPUT_MORE, put a copy of
1258          * the branch address in the first descriptor.
1259          *
1260          * Not doing this for transmit contexts since not sure how it interacts
1261          * with skip addresses.
1262          */
1263         if (unlikely(ctx->ohci->quirks & QUIRK_IR_WAKE) &&
1264             d_branch != ctx->prev &&
1265             (ctx->prev->control & cpu_to_le16(DESCRIPTOR_CMD)) ==
1266              cpu_to_le16(DESCRIPTOR_INPUT_MORE)) {
1267                 ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1268         }
1269 
1270         ctx->prev = d;
1271         ctx->prev_z = z;
1272 }
1273 
1274 static void context_stop(struct context *ctx)
1275 {
1276         struct fw_ohci *ohci = ctx->ohci;
1277         u32 reg;
1278         int i;
1279 
1280         reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1281         ctx->running = false;
1282 
1283         for (i = 0; i < 1000; i++) {
1284                 reg = reg_read(ohci, CONTROL_SET(ctx->regs));
1285                 if ((reg & CONTEXT_ACTIVE) == 0)
1286                         return;
1287 
1288                 if (i)
1289                         udelay(10);
1290         }
1291         ohci_err(ohci, "DMA context still active (0x%08x)\n", reg);
1292 }
1293 
1294 struct driver_data {
1295         u8 inline_data[8];
1296         struct fw_packet *packet;
1297 };
1298 
1299 /*
1300  * This function apppends a packet to the DMA queue for transmission.
1301  * Must always be called with the ochi->lock held to ensure proper
1302  * generation handling and locking around packet queue manipulation.
1303  */
1304 static int at_context_queue_packet(struct context *ctx,
1305                                    struct fw_packet *packet)
1306 {
1307         struct fw_ohci *ohci = ctx->ohci;
1308         dma_addr_t d_bus, uninitialized_var(payload_bus);
1309         struct driver_data *driver_data;
1310         struct descriptor *d, *last;
1311         __le32 *header;
1312         int z, tcode;
1313 
1314         d = context_get_descriptors(ctx, 4, &d_bus);
1315         if (d == NULL) {
1316                 packet->ack = RCODE_SEND_ERROR;
1317                 return -1;
1318         }
1319 
1320         d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1321         d[0].res_count = cpu_to_le16(packet->timestamp);
1322 
1323         /*
1324          * The DMA format for asynchronous link packets is different
1325          * from the IEEE1394 layout, so shift the fields around
1326          * accordingly.
1327          */
1328 
1329         tcode = (packet->header[0] >> 4) & 0x0f;
1330         header = (__le32 *) &d[1];
1331         switch (tcode) {
1332         case TCODE_WRITE_QUADLET_REQUEST:
1333         case TCODE_WRITE_BLOCK_REQUEST:
1334         case TCODE_WRITE_RESPONSE:
1335         case TCODE_READ_QUADLET_REQUEST:
1336         case TCODE_READ_BLOCK_REQUEST:
1337         case TCODE_READ_QUADLET_RESPONSE:
1338         case TCODE_READ_BLOCK_RESPONSE:
1339         case TCODE_LOCK_REQUEST:
1340         case TCODE_LOCK_RESPONSE:
1341                 header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1342                                         (packet->speed << 16));
1343                 header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1344                                         (packet->header[0] & 0xffff0000));
1345                 header[2] = cpu_to_le32(packet->header[2]);
1346 
1347                 if (TCODE_IS_BLOCK_PACKET(tcode))
1348                         header[3] = cpu_to_le32(packet->header[3]);
1349                 else
1350                         header[3] = (__force __le32) packet->header[3];
1351 
1352                 d[0].req_count = cpu_to_le16(packet->header_length);
1353                 break;
1354 
1355         case TCODE_LINK_INTERNAL:
1356                 header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1357                                         (packet->speed << 16));
1358                 header[1] = cpu_to_le32(packet->header[1]);
1359                 header[2] = cpu_to_le32(packet->header[2]);
1360                 d[0].req_count = cpu_to_le16(12);
1361 
1362                 if (is_ping_packet(&packet->header[1]))
1363                         d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1364                 break;
1365 
1366         case TCODE_STREAM_DATA:
1367                 header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1368                                         (packet->speed << 16));
1369                 header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1370                 d[0].req_count = cpu_to_le16(8);
1371                 break;
1372 
1373         default:
1374                 /* BUG(); */
1375                 packet->ack = RCODE_SEND_ERROR;
1376                 return -1;
1377         }
1378 
1379         BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1380         driver_data = (struct driver_data *) &d[3];
1381         driver_data->packet = packet;
1382         packet->driver_data = driver_data;
1383 
1384         if (packet->payload_length > 0) {
1385                 if (packet->payload_length > sizeof(driver_data->inline_data)) {
1386                         payload_bus = dma_map_single(ohci->card.device,
1387                                                      packet->payload,
1388                                                      packet->payload_length,
1389                                                      DMA_TO_DEVICE);
1390                         if (dma_mapping_error(ohci->card.device, payload_bus)) {
1391                                 packet->ack = RCODE_SEND_ERROR;
1392                                 return -1;
1393                         }
1394                         packet->payload_bus     = payload_bus;
1395                         packet->payload_mapped  = true;
1396                 } else {
1397                         memcpy(driver_data->inline_data, packet->payload,
1398                                packet->payload_length);
1399                         payload_bus = d_bus + 3 * sizeof(*d);
1400                 }
1401 
1402                 d[2].req_count    = cpu_to_le16(packet->payload_length);
1403                 d[2].data_address = cpu_to_le32(payload_bus);
1404                 last = &d[2];
1405                 z = 3;
1406         } else {
1407                 last = &d[0];
1408                 z = 2;
1409         }
1410 
1411         last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1412                                      DESCRIPTOR_IRQ_ALWAYS |
1413                                      DESCRIPTOR_BRANCH_ALWAYS);
1414 
1415         /* FIXME: Document how the locking works. */
1416         if (ohci->generation != packet->generation) {
1417                 if (packet->payload_mapped)
1418                         dma_unmap_single(ohci->card.device, payload_bus,
1419                                          packet->payload_length, DMA_TO_DEVICE);
1420                 packet->ack = RCODE_GENERATION;
1421                 return -1;
1422         }
1423 
1424         context_append(ctx, d, z, 4 - z);
1425 
1426         if (ctx->running)
1427                 reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1428         else
1429                 context_run(ctx, 0);
1430 
1431         return 0;
1432 }
1433 
1434 static void at_context_flush(struct context *ctx)
1435 {
1436         tasklet_disable(&ctx->tasklet);
1437 
1438         ctx->flushing = true;
1439         context_tasklet((unsigned long)ctx);
1440         ctx->flushing = false;
1441 
1442         tasklet_enable(&ctx->tasklet);
1443 }
1444 
1445 static int handle_at_packet(struct context *context,
1446                             struct descriptor *d,
1447                             struct descriptor *last)
1448 {
1449         struct driver_data *driver_data;
1450         struct fw_packet *packet;
1451         struct fw_ohci *ohci = context->ohci;
1452         int evt;
1453 
1454         if (last->transfer_status == 0 && !context->flushing)
1455                 /* This descriptor isn't done yet, stop iteration. */
1456                 return 0;
1457 
1458         driver_data = (struct driver_data *) &d[3];
1459         packet = driver_data->packet;
1460         if (packet == NULL)
1461                 /* This packet was cancelled, just continue. */
1462                 return 1;
1463 
1464         if (packet->payload_mapped)
1465                 dma_unmap_single(ohci->card.device, packet->payload_bus,
1466                                  packet->payload_length, DMA_TO_DEVICE);
1467 
1468         evt = le16_to_cpu(last->transfer_status) & 0x1f;
1469         packet->timestamp = le16_to_cpu(last->res_count);
1470 
1471         log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);
1472 
1473         switch (evt) {
1474         case OHCI1394_evt_timeout:
1475                 /* Async response transmit timed out. */
1476                 packet->ack = RCODE_CANCELLED;
1477                 break;
1478 
1479         case OHCI1394_evt_flushed:
1480                 /*
1481                  * The packet was flushed should give same error as
1482                  * when we try to use a stale generation count.
1483                  */
1484                 packet->ack = RCODE_GENERATION;
1485                 break;
1486 
1487         case OHCI1394_evt_missing_ack:
1488                 if (context->flushing)
1489                         packet->ack = RCODE_GENERATION;
1490                 else {
1491                         /*
1492                          * Using a valid (current) generation count, but the
1493                          * node is not on the bus or not sending acks.
1494                          */
1495                         packet->ack = RCODE_NO_ACK;
1496                 }
1497                 break;
1498 
1499         case ACK_COMPLETE + 0x10:
1500         case ACK_PENDING + 0x10:
1501         case ACK_BUSY_X + 0x10:
1502         case ACK_BUSY_A + 0x10:
1503         case ACK_BUSY_B + 0x10:
1504         case ACK_DATA_ERROR + 0x10:
1505         case ACK_TYPE_ERROR + 0x10:
1506                 packet->ack = evt - 0x10;
1507                 break;
1508 
1509         case OHCI1394_evt_no_status:
1510                 if (context->flushing) {
1511                         packet->ack = RCODE_GENERATION;
1512                         break;
1513                 }
1514                 /* fall through */
1515 
1516         default:
1517                 packet->ack = RCODE_SEND_ERROR;
1518                 break;
1519         }
1520 
1521         packet->callback(packet, &ohci->card, packet->ack);
1522 
1523         return 1;
1524 }
1525 
1526 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
1527 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
1528 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
1529 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
1530 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
1531 
1532 static void handle_local_rom(struct fw_ohci *ohci,
1533                              struct fw_packet *packet, u32 csr)
1534 {
1535         struct fw_packet response;
1536         int tcode, length, i;
1537 
1538         tcode = HEADER_GET_TCODE(packet->header[0]);
1539         if (TCODE_IS_BLOCK_PACKET(tcode))
1540                 length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1541         else
1542                 length = 4;
1543 
1544         i = csr - CSR_CONFIG_ROM;
1545         if (i + length > CONFIG_ROM_SIZE) {
1546                 fw_fill_response(&response, packet->header,
1547                                  RCODE_ADDRESS_ERROR, NULL, 0);
1548         } else if (!TCODE_IS_READ_REQUEST(tcode)) {
1549                 fw_fill_response(&response, packet->header,
1550                                  RCODE_TYPE_ERROR, NULL, 0);
1551         } else {
1552                 fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1553                                  (void *) ohci->config_rom + i, length);
1554         }
1555 
1556         fw_core_handle_response(&ohci->card, &response);
1557 }
1558 
1559 static void handle_local_lock(struct fw_ohci *ohci,
1560                               struct fw_packet *packet, u32 csr)
1561 {
1562         struct fw_packet response;
1563         int tcode, length, ext_tcode, sel, try;
1564         __be32 *payload, lock_old;
1565         u32 lock_arg, lock_data;
1566 
1567         tcode = HEADER_GET_TCODE(packet->header[0]);
1568         length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1569         payload = packet->payload;
1570         ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1571 
1572         if (tcode == TCODE_LOCK_REQUEST &&
1573             ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1574                 lock_arg = be32_to_cpu(payload[0]);
1575                 lock_data = be32_to_cpu(payload[1]);
1576         } else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1577                 lock_arg = 0;
1578                 lock_data = 0;
1579         } else {
1580                 fw_fill_response(&response, packet->header,
1581                                  RCODE_TYPE_ERROR, NULL, 0);
1582                 goto out;
1583         }
1584 
1585         sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1586         reg_write(ohci, OHCI1394_CSRData, lock_data);
1587         reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1588         reg_write(ohci, OHCI1394_CSRControl, sel);
1589 
1590         for (try = 0; try < 20; try++)
1591                 if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1592                         lock_old = cpu_to_be32(reg_read(ohci,
1593                                                         OHCI1394_CSRData));
1594                         fw_fill_response(&response, packet->header,
1595                                          RCODE_COMPLETE,
1596                                          &lock_old, sizeof(lock_old));
1597                         goto out;
1598                 }
1599 
1600         ohci_err(ohci, "swap not done (CSR lock timeout)\n");
1601         fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1602 
1603  out:
1604         fw_core_handle_response(&ohci->card, &response);
1605 }
1606 
1607 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1608 {
1609         u64 offset, csr;
1610 
1611         if (ctx == &ctx->ohci->at_request_ctx) {
1612                 packet->ack = ACK_PENDING;
1613                 packet->callback(packet, &ctx->ohci->card, packet->ack);
1614         }
1615 
1616         offset =
1617                 ((unsigned long long)
1618                  HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1619                 packet->header[2];
1620         csr = offset - CSR_REGISTER_BASE;
1621 
1622         /* Handle config rom reads. */
1623         if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1624                 handle_local_rom(ctx->ohci, packet, csr);
1625         else switch (csr) {
1626         case CSR_BUS_MANAGER_ID:
1627         case CSR_BANDWIDTH_AVAILABLE:
1628         case CSR_CHANNELS_AVAILABLE_HI:
1629         case CSR_CHANNELS_AVAILABLE_LO:
1630                 handle_local_lock(ctx->ohci, packet, csr);
1631                 break;
1632         default:
1633                 if (ctx == &ctx->ohci->at_request_ctx)
1634                         fw_core_handle_request(&ctx->ohci->card, packet);
1635                 else
1636                         fw_core_handle_response(&ctx->ohci->card, packet);
1637                 break;
1638         }
1639 
1640         if (ctx == &ctx->ohci->at_response_ctx) {
1641                 packet->ack = ACK_COMPLETE;
1642                 packet->callback(packet, &ctx->ohci->card, packet->ack);
1643         }
1644 }
1645 
1646 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1647 {
1648         unsigned long flags;
1649         int ret;
1650 
1651         spin_lock_irqsave(&ctx->ohci->lock, flags);
1652 
1653         if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1654             ctx->ohci->generation == packet->generation) {
1655                 spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1656                 handle_local_request(ctx, packet);
1657                 return;
1658         }
1659 
1660         ret = at_context_queue_packet(ctx, packet);
1661         spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1662 
1663         if (ret < 0)
1664                 packet->callback(packet, &ctx->ohci->card, packet->ack);
1665 
1666 }
1667 
1668 static void detect_dead_context(struct fw_ohci *ohci,
1669                                 const char *name, unsigned int regs)
1670 {
1671         u32 ctl;
1672 
1673         ctl = reg_read(ohci, CONTROL_SET(regs));
1674         if (ctl & CONTEXT_DEAD)
1675                 ohci_err(ohci, "DMA context %s has stopped, error code: %s\n",
1676                         name, evts[ctl & 0x1f]);
1677 }
1678 
1679 static void handle_dead_contexts(struct fw_ohci *ohci)
1680 {
1681         unsigned int i;
1682         char name[8];
1683 
1684         detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1685         detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1686         detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1687         detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1688         for (i = 0; i < 32; ++i) {
1689                 if (!(ohci->it_context_support & (1 << i)))
1690                         continue;
1691                 sprintf(name, "IT%u", i);
1692                 detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1693         }
1694         for (i = 0; i < 32; ++i) {
1695                 if (!(ohci->ir_context_support & (1 << i)))
1696                         continue;
1697                 sprintf(name, "IR%u", i);
1698                 detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1699         }
1700         /* TODO: maybe try to flush and restart the dead contexts */
1701 }
1702 
1703 static u32 cycle_timer_ticks(u32 cycle_timer)
1704 {
1705         u32 ticks;
1706 
1707         ticks = cycle_timer & 0xfff;
1708         ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1709         ticks += (3072 * 8000) * (cycle_timer >> 25);
1710 
1711         return ticks;
1712 }
1713 
1714 /*
1715  * Some controllers exhibit one or more of the following bugs when updating the
1716  * iso cycle timer register:
1717  *  - When the lowest six bits are wrapping around to zero, a read that happens
1718  *    at the same time will return garbage in the lowest ten bits.
1719  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1720  *    not incremented for about 60 ns.
1721  *  - Occasionally, the entire register reads zero.
1722  *
1723  * To catch these, we read the register three times and ensure that the
1724  * difference between each two consecutive reads is approximately the same, i.e.
1725  * less than twice the other.  Furthermore, any negative difference indicates an
1726  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1727  * execute, so we have enough precision to compute the ratio of the differences.)
1728  */
1729 static u32 get_cycle_time(struct fw_ohci *ohci)
1730 {
1731         u32 c0, c1, c2;
1732         u32 t0, t1, t2;
1733         s32 diff01, diff12;
1734         int i;
1735 
1736         c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1737 
1738         if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1739                 i = 0;
1740                 c1 = c2;
1741                 c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1742                 do {
1743                         c0 = c1;
1744                         c1 = c2;
1745                         c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1746                         t0 = cycle_timer_ticks(c0);
1747                         t1 = cycle_timer_ticks(c1);
1748                         t2 = cycle_timer_ticks(c2);
1749                         diff01 = t1 - t0;
1750                         diff12 = t2 - t1;
1751                 } while ((diff01 <= 0 || diff12 <= 0 ||
1752                           diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1753                          && i++ < 20);
1754         }
1755 
1756         return c2;
1757 }
1758 
1759 /*
1760  * This function has to be called at least every 64 seconds.  The bus_time
1761  * field stores not only the upper 25 bits of the BUS_TIME register but also
1762  * the most significant bit of the cycle timer in bit 6 so that we can detect
1763  * changes in this bit.
1764  */
1765 static u32 update_bus_time(struct fw_ohci *ohci)
1766 {
1767         u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1768 
1769         if (unlikely(!ohci->bus_time_running)) {
1770                 reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_cycle64Seconds);
1771                 ohci->bus_time = (lower_32_bits(get_seconds()) & ~0x7f) |
1772                                  (cycle_time_seconds & 0x40);
1773                 ohci->bus_time_running = true;
1774         }
1775 
1776         if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1777                 ohci->bus_time += 0x40;
1778 
1779         return ohci->bus_time | cycle_time_seconds;
1780 }
1781 
1782 static int get_status_for_port(struct fw_ohci *ohci, int port_index)
1783 {
1784         int reg;
1785 
1786         mutex_lock(&ohci->phy_reg_mutex);
1787         reg = write_phy_reg(ohci, 7, port_index);
1788         if (reg >= 0)
1789                 reg = read_phy_reg(ohci, 8);
1790         mutex_unlock(&ohci->phy_reg_mutex);
1791         if (reg < 0)
1792                 return reg;
1793 
1794         switch (reg & 0x0f) {
1795         case 0x06:
1796                 return 2;       /* is child node (connected to parent node) */
1797         case 0x0e:
1798                 return 3;       /* is parent node (connected to child node) */
1799         }
1800         return 1;               /* not connected */
1801 }
1802 
1803 static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
1804         int self_id_count)
1805 {
1806         int i;
1807         u32 entry;
1808 
1809         for (i = 0; i < self_id_count; i++) {
1810                 entry = ohci->self_id_buffer[i];
1811                 if ((self_id & 0xff000000) == (entry & 0xff000000))
1812                         return -1;
1813                 if ((self_id & 0xff000000) < (entry & 0xff000000))
1814                         return i;
1815         }
1816         return i;
1817 }
1818 
1819 static int initiated_reset(struct fw_ohci *ohci)
1820 {
1821         int reg;
1822         int ret = 0;
1823 
1824         mutex_lock(&ohci->phy_reg_mutex);
1825         reg = write_phy_reg(ohci, 7, 0xe0); /* Select page 7 */
1826         if (reg >= 0) {
1827                 reg = read_phy_reg(ohci, 8);
1828                 reg |= 0x40;
1829                 reg = write_phy_reg(ohci, 8, reg); /* set PMODE bit */
1830                 if (reg >= 0) {
1831                         reg = read_phy_reg(ohci, 12); /* read register 12 */
1832                         if (reg >= 0) {
1833                                 if ((reg & 0x08) == 0x08) {
1834                                         /* bit 3 indicates "initiated reset" */
1835                                         ret = 0x2;
1836                                 }
1837                         }
1838                 }
1839         }
1840         mutex_unlock(&ohci->phy_reg_mutex);
1841         return ret;
1842 }
1843 
1844 /*
1845  * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
1846  * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
1847  * Construct the selfID from phy register contents.
1848  */
1849 static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
1850 {
1851         int reg, i, pos, status;
1852         /* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
1853         u32 self_id = 0x8040c800;
1854 
1855         reg = reg_read(ohci, OHCI1394_NodeID);
1856         if (!(reg & OHCI1394_NodeID_idValid)) {
1857                 ohci_notice(ohci,
1858                             "node ID not valid, new bus reset in progress\n");
1859                 return -EBUSY;
1860         }
1861         self_id |= ((reg & 0x3f) << 24); /* phy ID */
1862 
1863         reg = ohci_read_phy_reg(&ohci->card, 4);
1864         if (reg < 0)
1865                 return reg;
1866         self_id |= ((reg & 0x07) << 8); /* power class */
1867 
1868         reg = ohci_read_phy_reg(&ohci->card, 1);
1869         if (reg < 0)
1870                 return reg;
1871         self_id |= ((reg & 0x3f) << 16); /* gap count */
1872 
1873         for (i = 0; i < 3; i++) {
1874                 status = get_status_for_port(ohci, i);
1875                 if (status < 0)
1876                         return status;
1877                 self_id |= ((status & 0x3) << (6 - (i * 2)));
1878         }
1879 
1880         self_id |= initiated_reset(ohci);
1881 
1882         pos = get_self_id_pos(ohci, self_id, self_id_count);
1883         if (pos >= 0) {
1884                 memmove(&(ohci->self_id_buffer[pos+1]),
1885                         &(ohci->self_id_buffer[pos]),
1886                         (self_id_count - pos) * sizeof(*ohci->self_id_buffer));
1887                 ohci->self_id_buffer[pos] = self_id;
1888                 self_id_count++;
1889         }
1890         return self_id_count;
1891 }
1892 
1893 static void bus_reset_work(struct work_struct *work)
1894 {
1895         struct fw_ohci *ohci =
1896                 container_of(work, struct fw_ohci, bus_reset_work);
1897         int self_id_count, generation, new_generation, i, j;
1898         u32 reg;
1899         void *free_rom = NULL;
1900         dma_addr_t free_rom_bus = 0;
1901         bool is_new_root;
1902 
1903         reg = reg_read(ohci, OHCI1394_NodeID);
1904         if (!(reg & OHCI1394_NodeID_idValid)) {
1905                 ohci_notice(ohci,
1906                             "node ID not valid, new bus reset in progress\n");
1907                 return;
1908         }
1909         if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1910                 ohci_notice(ohci, "malconfigured bus\n");
1911                 return;
1912         }
1913         ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1914                                OHCI1394_NodeID_nodeNumber);
1915 
1916         is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1917         if (!(ohci->is_root && is_new_root))
1918                 reg_write(ohci, OHCI1394_LinkControlSet,
1919                           OHCI1394_LinkControl_cycleMaster);
1920         ohci->is_root = is_new_root;
1921 
1922         reg = reg_read(ohci, OHCI1394_SelfIDCount);
1923         if (reg & OHCI1394_SelfIDCount_selfIDError) {
1924                 ohci_notice(ohci, "self ID receive error\n");
1925                 return;
1926         }
1927         /*
1928          * The count in the SelfIDCount register is the number of
1929          * bytes in the self ID receive buffer.  Since we also receive
1930          * the inverted quadlets and a header quadlet, we shift one
1931          * bit extra to get the actual number of self IDs.
1932          */
1933         self_id_count = (reg >> 3) & 0xff;
1934 
1935         if (self_id_count > 252) {
1936                 ohci_notice(ohci, "bad selfIDSize (%08x)\n", reg);
1937                 return;
1938         }
1939 
1940         generation = (cond_le32_to_cpu(ohci->self_id[0]) >> 16) & 0xff;
1941         rmb();
1942 
1943         for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1944                 u32 id  = cond_le32_to_cpu(ohci->self_id[i]);
1945                 u32 id2 = cond_le32_to_cpu(ohci->self_id[i + 1]);
1946 
1947                 if (id != ~id2) {
1948                         /*
1949                          * If the invalid data looks like a cycle start packet,
1950                          * it's likely to be the result of the cycle master
1951                          * having a wrong gap count.  In this case, the self IDs
1952                          * so far are valid and should be processed so that the
1953                          * bus manager can then correct the gap count.
1954                          */
1955                         if (id == 0xffff008f) {
1956                                 ohci_notice(ohci, "ignoring spurious self IDs\n");
1957                                 self_id_count = j;
1958                                 break;
1959                         }
1960 
1961                         ohci_notice(ohci, "bad self ID %d/%d (%08x != ~%08x)\n",
1962                                     j, self_id_count, id, id2);
1963                         return;
1964                 }
1965                 ohci->self_id_buffer[j] = id;
1966         }
1967 
1968         if (ohci->quirks & QUIRK_TI_SLLZ059) {
1969                 self_id_count = find_and_insert_self_id(ohci, self_id_count);
1970                 if (self_id_count < 0) {
1971                         ohci_notice(ohci,
1972                                     "could not construct local self ID\n");
1973                         return;
1974                 }
1975         }
1976 
1977         if (self_id_count == 0) {
1978                 ohci_notice(ohci, "no self IDs\n");
1979                 return;
1980         }
1981         rmb();
1982 
1983         /*
1984          * Check the consistency of the self IDs we just read.  The
1985          * problem we face is that a new bus reset can start while we
1986          * read out the self IDs from the DMA buffer. If this happens,
1987          * the DMA buffer will be overwritten with new self IDs and we
1988          * will read out inconsistent data.  The OHCI specification
1989          * (section 11.2) recommends a technique similar to
1990          * linux/seqlock.h, where we remember the generation of the
1991          * self IDs in the buffer before reading them out and compare
1992          * it to the current generation after reading them out.  If
1993          * the two generations match we know we have a consistent set
1994          * of self IDs.
1995          */
1996 
1997         new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1998         if (new_generation != generation) {
1999                 ohci_notice(ohci, "new bus reset, discarding self ids\n");
2000                 return;
2001         }
2002 
2003         /* FIXME: Document how the locking works. */
2004         spin_lock_irq(&ohci->lock);
2005 
2006         ohci->generation = -1; /* prevent AT packet queueing */
2007         context_stop(&ohci->at_request_ctx);
2008         context_stop(&ohci->at_response_ctx);
2009 
2010         spin_unlock_irq(&ohci->lock);
2011 
2012         /*
2013          * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
2014          * packets in the AT queues and software needs to drain them.
2015          * Some OHCI 1.1 controllers (JMicron) apparently require this too.
2016          */
2017         at_context_flush(&ohci->at_request_ctx);
2018         at_context_flush(&ohci->at_response_ctx);
2019 
2020         spin_lock_irq(&ohci->lock);
2021 
2022         ohci->generation = generation;
2023         reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
2024 
2025         if (ohci->quirks & QUIRK_RESET_PACKET)
2026                 ohci->request_generation = generation;
2027 
2028         /*
2029          * This next bit is unrelated to the AT context stuff but we
2030          * have to do it under the spinlock also.  If a new config rom
2031          * was set up before this reset, the old one is now no longer
2032          * in use and we can free it. Update the config rom pointers
2033          * to point to the current config rom and clear the
2034          * next_config_rom pointer so a new update can take place.
2035          */
2036 
2037         if (ohci->next_config_rom != NULL) {
2038                 if (ohci->next_config_rom != ohci->config_rom) {
2039                         free_rom      = ohci->config_rom;
2040                         free_rom_bus  = ohci->config_rom_bus;
2041                 }
2042                 ohci->config_rom      = ohci->next_config_rom;
2043                 ohci->config_rom_bus  = ohci->next_config_rom_bus;
2044                 ohci->next_config_rom = NULL;
2045 
2046                 /*
2047                  * Restore config_rom image and manually update
2048                  * config_rom registers.  Writing the header quadlet
2049                  * will indicate that the config rom is ready, so we
2050                  * do that last.
2051                  */
2052                 reg_write(ohci, OHCI1394_BusOptions,
2053                           be32_to_cpu(ohci->config_rom[2]));
2054                 ohci->config_rom[0] = ohci->next_header;
2055                 reg_write(ohci, OHCI1394_ConfigROMhdr,
2056                           be32_to_cpu(ohci->next_header));
2057         }
2058 
2059         if (param_remote_dma) {
2060                 reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
2061                 reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
2062         }
2063 
2064         spin_unlock_irq(&ohci->lock);
2065 
2066         if (free_rom)
2067                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2068                                   free_rom, free_rom_bus);
2069 
2070         log_selfids(ohci, generation, self_id_count);
2071 
2072         fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
2073                                  self_id_count, ohci->self_id_buffer,
2074                                  ohci->csr_state_setclear_abdicate);
2075         ohci->csr_state_setclear_abdicate = false;
2076 }
2077 
2078 static irqreturn_t irq_handler(int irq, void *data)
2079 {
2080         struct fw_ohci *ohci = data;
2081         u32 event, iso_event;
2082         int i;
2083 
2084         event = reg_read(ohci, OHCI1394_IntEventClear);
2085 
2086         if (!event || !~event)
2087                 return IRQ_NONE;
2088 
2089         /*
2090          * busReset and postedWriteErr must not be cleared yet
2091          * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
2092          */
2093         reg_write(ohci, OHCI1394_IntEventClear,
2094                   event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
2095         log_irqs(ohci, event);
2096 
2097         if (event & OHCI1394_selfIDComplete)
2098                 queue_work(selfid_workqueue, &ohci->bus_reset_work);
2099 
2100         if (event & OHCI1394_RQPkt)
2101                 tasklet_schedule(&ohci->ar_request_ctx.tasklet);
2102 
2103         if (event & OHCI1394_RSPkt)
2104                 tasklet_schedule(&ohci->ar_response_ctx.tasklet);
2105 
2106         if (event & OHCI1394_reqTxComplete)
2107                 tasklet_schedule(&ohci->at_request_ctx.tasklet);
2108 
2109         if (event & OHCI1394_respTxComplete)
2110                 tasklet_schedule(&ohci->at_response_ctx.tasklet);
2111 
2112         if (event & OHCI1394_isochRx) {
2113                 iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
2114                 reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
2115 
2116                 while (iso_event) {
2117                         i = ffs(iso_event) - 1;
2118                         tasklet_schedule(
2119                                 &ohci->ir_context_list[i].context.tasklet);
2120                         iso_event &= ~(1 << i);
2121                 }
2122         }
2123 
2124         if (event & OHCI1394_isochTx) {
2125                 iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
2126                 reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
2127 
2128                 while (iso_event) {
2129                         i = ffs(iso_event) - 1;
2130                         tasklet_schedule(
2131                                 &ohci->it_context_list[i].context.tasklet);
2132                         iso_event &= ~(1 << i);
2133                 }
2134         }
2135 
2136         if (unlikely(event & OHCI1394_regAccessFail))
2137                 ohci_err(ohci, "register access failure\n");
2138 
2139         if (unlikely(event & OHCI1394_postedWriteErr)) {
2140                 reg_read(ohci, OHCI1394_PostedWriteAddressHi);
2141                 reg_read(ohci, OHCI1394_PostedWriteAddressLo);
2142                 reg_write(ohci, OHCI1394_IntEventClear,
2143                           OHCI1394_postedWriteErr);
2144                 if (printk_ratelimit())
2145                         ohci_err(ohci, "PCI posted write error\n");
2146         }
2147 
2148         if (unlikely(event & OHCI1394_cycleTooLong)) {
2149                 if (printk_ratelimit())
2150                         ohci_notice(ohci, "isochronous cycle too long\n");
2151                 reg_write(ohci, OHCI1394_LinkControlSet,
2152                           OHCI1394_LinkControl_cycleMaster);
2153         }
2154 
2155         if (unlikely(event & OHCI1394_cycleInconsistent)) {
2156                 /*
2157                  * We need to clear this event bit in order to make
2158                  * cycleMatch isochronous I/O work.  In theory we should
2159                  * stop active cycleMatch iso contexts now and restart
2160                  * them at least two cycles later.  (FIXME?)
2161                  */
2162                 if (printk_ratelimit())
2163                         ohci_notice(ohci, "isochronous cycle inconsistent\n");
2164         }
2165 
2166         if (unlikely(event & OHCI1394_unrecoverableError))
2167                 handle_dead_contexts(ohci);
2168 
2169         if (event & OHCI1394_cycle64Seconds) {
2170                 spin_lock(&ohci->lock);
2171                 update_bus_time(ohci);
2172                 spin_unlock(&ohci->lock);
2173         } else
2174                 flush_writes(ohci);
2175 
2176         return IRQ_HANDLED;
2177 }
2178 
2179 static int software_reset(struct fw_ohci *ohci)
2180 {
2181         u32 val;
2182         int i;
2183 
2184         reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
2185         for (i = 0; i < 500; i++) {
2186                 val = reg_read(ohci, OHCI1394_HCControlSet);
2187                 if (!~val)
2188                         return -ENODEV; /* Card was ejected. */
2189 
2190                 if (!(val & OHCI1394_HCControl_softReset))
2191                         return 0;
2192 
2193                 msleep(1);
2194         }
2195 
2196         return -EBUSY;
2197 }
2198 
2199 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
2200 {
2201         size_t size = length * 4;
2202 
2203         memcpy(dest, src, size);
2204         if (size < CONFIG_ROM_SIZE)
2205                 memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
2206 }
2207 
2208 static int configure_1394a_enhancements(struct fw_ohci *ohci)
2209 {
2210         bool enable_1394a;
2211         int ret, clear, set, offset;
2212 
2213         /* Check if the driver should configure link and PHY. */
2214         if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2215               OHCI1394_HCControl_programPhyEnable))
2216                 return 0;
2217 
2218         /* Paranoia: check whether the PHY supports 1394a, too. */
2219         enable_1394a = false;
2220         ret = read_phy_reg(ohci, 2);
2221         if (ret < 0)
2222                 return ret;
2223         if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2224                 ret = read_paged_phy_reg(ohci, 1, 8);
2225                 if (ret < 0)
2226                         return ret;
2227                 if (ret >= 1)
2228                         enable_1394a = true;
2229         }
2230 
2231         if (ohci->quirks & QUIRK_NO_1394A)
2232                 enable_1394a = false;
2233 
2234         /* Configure PHY and link consistently. */
2235         if (enable_1394a) {
2236                 clear = 0;
2237                 set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2238         } else {
2239                 clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2240                 set = 0;
2241         }
2242         ret = update_phy_reg(ohci, 5, clear, set);
2243         if (ret < 0)
2244                 return ret;
2245 
2246         if (enable_1394a)
2247                 offset = OHCI1394_HCControlSet;
2248         else
2249                 offset = OHCI1394_HCControlClear;
2250         reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2251 
2252         /* Clean up: configuration has been taken care of. */
2253         reg_write(ohci, OHCI1394_HCControlClear,
2254                   OHCI1394_HCControl_programPhyEnable);
2255 
2256         return 0;
2257 }
2258 
2259 static int probe_tsb41ba3d(struct fw_ohci *ohci)
2260 {
2261         /* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
2262         static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
2263         int reg, i;
2264 
2265         reg = read_phy_reg(ohci, 2);
2266         if (reg < 0)
2267                 return reg;
2268         if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
2269                 return 0;
2270 
2271         for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
2272                 reg = read_paged_phy_reg(ohci, 1, i + 10);
2273                 if (reg < 0)
2274                         return reg;
2275                 if (reg != id[i])
2276                         return 0;
2277         }
2278         return 1;
2279 }
2280 
2281 static int ohci_enable(struct fw_card *card,
2282                        const __be32 *config_rom, size_t length)
2283 {
2284         struct fw_ohci *ohci = fw_ohci(card);
2285         u32 lps, version, irqs;
2286         int i, ret;
2287 
2288         if (software_reset(ohci)) {
2289                 ohci_err(ohci, "failed to reset ohci card\n");
2290                 return -EBUSY;
2291         }
2292 
2293         /*
2294          * Now enable LPS, which we need in order to start accessing
2295          * most of the registers.  In fact, on some cards (ALI M5251),
2296          * accessing registers in the SClk domain without LPS enabled
2297          * will lock up the machine.  Wait 50msec to make sure we have
2298          * full link enabled.  However, with some cards (well, at least
2299          * a JMicron PCIe card), we have to try again sometimes.
2300          *
2301          * TI TSB82AA2 + TSB81BA3(A) cards signal LPS enabled early but
2302          * cannot actually use the phy at that time.  These need tens of
2303          * millisecods pause between LPS write and first phy access too.
2304          */
2305 
2306         reg_write(ohci, OHCI1394_HCControlSet,
2307                   OHCI1394_HCControl_LPS |
2308                   OHCI1394_HCControl_postedWriteEnable);
2309         flush_writes(ohci);
2310 
2311         for (lps = 0, i = 0; !lps && i < 3; i++) {
2312                 msleep(50);
2313                 lps = reg_read(ohci, OHCI1394_HCControlSet) &
2314                       OHCI1394_HCControl_LPS;
2315         }
2316 
2317         if (!lps) {
2318                 ohci_err(ohci, "failed to set Link Power Status\n");
2319                 return -EIO;
2320         }
2321 
2322         if (ohci->quirks & QUIRK_TI_SLLZ059) {
2323                 ret = probe_tsb41ba3d(ohci);
2324                 if (ret < 0)
2325                         return ret;
2326                 if (ret)
2327                         ohci_notice(ohci, "local TSB41BA3D phy\n");
2328                 else
2329                         ohci->quirks &= ~QUIRK_TI_SLLZ059;
2330         }
2331 
2332         reg_write(ohci, OHCI1394_HCControlClear,
2333                   OHCI1394_HCControl_noByteSwapData);
2334 
2335         reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2336         reg_write(ohci, OHCI1394_LinkControlSet,
2337                   OHCI1394_LinkControl_cycleTimerEnable |
2338                   OHCI1394_LinkControl_cycleMaster);
2339 
2340         reg_write(ohci, OHCI1394_ATRetries,
2341                   OHCI1394_MAX_AT_REQ_RETRIES |
2342                   (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2343                   (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2344                   (200 << 16));
2345 
2346         ohci->bus_time_running = false;
2347 
2348         for (i = 0; i < 32; i++)
2349                 if (ohci->ir_context_support & (1 << i))
2350                         reg_write(ohci, OHCI1394_IsoRcvContextControlClear(i),
2351                                   IR_CONTEXT_MULTI_CHANNEL_MODE);
2352 
2353         version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2354         if (version >= OHCI_VERSION_1_1) {
2355                 reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2356                           0xfffffffe);
2357                 card->broadcast_channel_auto_allocated = true;
2358         }
2359 
2360         /* Get implemented bits of the priority arbitration request counter. */
2361         reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2362         ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2363         reg_write(ohci, OHCI1394_FairnessControl, 0);
2364         card->priority_budget_implemented = ohci->pri_req_max != 0;
2365 
2366         reg_write(ohci, OHCI1394_PhyUpperBound, FW_MAX_PHYSICAL_RANGE >> 16);
2367         reg_write(ohci, OHCI1394_IntEventClear, ~0);
2368         reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2369 
2370         ret = configure_1394a_enhancements(ohci);
2371         if (ret < 0)
2372                 return ret;
2373 
2374         /* Activate link_on bit and contender bit in our self ID packets.*/
2375         ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2376         if (ret < 0)
2377                 return ret;
2378 
2379         /*
2380          * When the link is not yet enabled, the atomic config rom
2381          * update mechanism described below in ohci_set_config_rom()
2382          * is not active.  We have to update ConfigRomHeader and
2383          * BusOptions manually, and the write to ConfigROMmap takes
2384          * effect immediately.  We tie this to the enabling of the
2385          * link, so we have a valid config rom before enabling - the
2386          * OHCI requires that ConfigROMhdr and BusOptions have valid
2387          * values before enabling.
2388          *
2389          * However, when the ConfigROMmap is written, some controllers
2390          * always read back quadlets 0 and 2 from the config rom to
2391          * the ConfigRomHeader and BusOptions registers on bus reset.
2392          * They shouldn't do that in this initial case where the link
2393          * isn't enabled.  This means we have to use the same
2394          * workaround here, setting the bus header to 0 and then write
2395          * the right values in the bus reset tasklet.
2396          */
2397 
2398         if (config_rom) {
2399                 ohci->next_config_rom =
2400                         dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2401                                            &ohci->next_config_rom_bus,
2402                                            GFP_KERNEL);
2403                 if (ohci->next_config_rom == NULL)
2404                         return -ENOMEM;
2405 
2406                 copy_config_rom(ohci->next_config_rom, config_rom, length);
2407         } else {
2408                 /*
2409                  * In the suspend case, config_rom is NULL, which
2410                  * means that we just reuse the old config rom.
2411                  */
2412                 ohci->next_config_rom = ohci->config_rom;
2413                 ohci->next_config_rom_bus = ohci->config_rom_bus;
2414         }
2415 
2416         ohci->next_header = ohci->next_config_rom[0];
2417         ohci->next_config_rom[0] = 0;
2418         reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2419         reg_write(ohci, OHCI1394_BusOptions,
2420                   be32_to_cpu(ohci->next_config_rom[2]));
2421         reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2422 
2423         reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2424 
2425         irqs =  OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2426                 OHCI1394_RQPkt | OHCI1394_RSPkt |
2427                 OHCI1394_isochTx | OHCI1394_isochRx |
2428                 OHCI1394_postedWriteErr |
2429                 OHCI1394_selfIDComplete |
2430                 OHCI1394_regAccessFail |
2431                 OHCI1394_cycleInconsistent |
2432                 OHCI1394_unrecoverableError |
2433                 OHCI1394_cycleTooLong |
2434                 OHCI1394_masterIntEnable;
2435         if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2436                 irqs |= OHCI1394_busReset;
2437         reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2438 
2439         reg_write(ohci, OHCI1394_HCControlSet,
2440                   OHCI1394_HCControl_linkEnable |
2441                   OHCI1394_HCControl_BIBimageValid);
2442 
2443         reg_write(ohci, OHCI1394_LinkControlSet,
2444                   OHCI1394_LinkControl_rcvSelfID |
2445                   OHCI1394_LinkControl_rcvPhyPkt);
2446 
2447         ar_context_run(&ohci->ar_request_ctx);
2448         ar_context_run(&ohci->ar_response_ctx);
2449 
2450         flush_writes(ohci);
2451 
2452         /* We are ready to go, reset bus to finish initialization. */
2453         fw_schedule_bus_reset(&ohci->card, false, true);
2454 
2455         return 0;
2456 }
2457 
2458 static int ohci_set_config_rom(struct fw_card *card,
2459                                const __be32 *config_rom, size_t length)
2460 {
2461         struct fw_ohci *ohci;
2462         __be32 *next_config_rom;
2463         dma_addr_t uninitialized_var(next_config_rom_bus);
2464 
2465         ohci = fw_ohci(card);
2466 
2467         /*
2468          * When the OHCI controller is enabled, the config rom update
2469          * mechanism is a bit tricky, but easy enough to use.  See
2470          * section 5.5.6 in the OHCI specification.
2471          *
2472          * The OHCI controller caches the new config rom address in a
2473          * shadow register (ConfigROMmapNext) and needs a bus reset
2474          * for the changes to take place.  When the bus reset is
2475          * detected, the controller loads the new values for the
2476          * ConfigRomHeader and BusOptions registers from the specified
2477          * config rom and loads ConfigROMmap from the ConfigROMmapNext
2478          * shadow register. All automatically and atomically.
2479          *
2480          * Now, there's a twist to this story.  The automatic load of
2481          * ConfigRomHeader and BusOptions doesn't honor the
2482          * noByteSwapData bit, so with a be32 config rom, the
2483          * controller will load be32 values in to these registers
2484          * during the atomic update, even on litte endian
2485          * architectures.  The workaround we use is to put a 0 in the
2486          * header quadlet; 0 is endian agnostic and means that the
2487          * config rom isn't ready yet.  In the bus reset tasklet we
2488          * then set up the real values for the two registers.
2489          *
2490          * We use ohci->lock to avoid racing with the code that sets
2491          * ohci->next_config_rom to NULL (see bus_reset_work).
2492          */
2493 
2494         next_config_rom =
2495                 dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2496                                    &next_config_rom_bus, GFP_KERNEL);
2497         if (next_config_rom == NULL)
2498                 return -ENOMEM;
2499 
2500         spin_lock_irq(&ohci->lock);
2501 
2502         /*
2503          * If there is not an already pending config_rom update,
2504          * push our new allocation into the ohci->next_config_rom
2505          * and then mark the local variable as null so that we
2506          * won't deallocate the new buffer.
2507          *
2508          * OTOH, if there is a pending config_rom update, just
2509          * use that buffer with the new config_rom data, and
2510          * let this routine free the unused DMA allocation.
2511          */
2512 
2513         if (ohci->next_config_rom == NULL) {
2514                 ohci->next_config_rom = next_config_rom;
2515                 ohci->next_config_rom_bus = next_config_rom_bus;
2516                 next_config_rom = NULL;
2517         }
2518 
2519         copy_config_rom(ohci->next_config_rom, config_rom, length);
2520 
2521         ohci->next_header = config_rom[0];
2522         ohci->next_config_rom[0] = 0;
2523 
2524         reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2525 
2526         spin_unlock_irq(&ohci->lock);
2527 
2528         /* If we didn't use the DMA allocation, delete it. */
2529         if (next_config_rom != NULL)
2530                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2531                                   next_config_rom, next_config_rom_bus);
2532 
2533         /*
2534          * Now initiate a bus reset to have the changes take
2535          * effect. We clean up the old config rom memory and DMA
2536          * mappings in the bus reset tasklet, since the OHCI
2537          * controller could need to access it before the bus reset
2538          * takes effect.
2539          */
2540 
2541         fw_schedule_bus_reset(&ohci->card, true, true);
2542 
2543         return 0;
2544 }
2545 
2546 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2547 {
2548         struct fw_ohci *ohci = fw_ohci(card);
2549 
2550         at_context_transmit(&ohci->at_request_ctx, packet);
2551 }
2552 
2553 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2554 {
2555         struct fw_ohci *ohci = fw_ohci(card);
2556 
2557         at_context_transmit(&ohci->at_response_ctx, packet);
2558 }
2559 
2560 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2561 {
2562         struct fw_ohci *ohci = fw_ohci(card);
2563         struct context *ctx = &ohci->at_request_ctx;
2564         struct driver_data *driver_data = packet->driver_data;
2565         int ret = -ENOENT;
2566 
2567         tasklet_disable(&ctx->tasklet);
2568 
2569         if (packet->ack != 0)
2570                 goto out;
2571 
2572         if (packet->payload_mapped)
2573                 dma_unmap_single(ohci->card.device, packet->payload_bus,
2574                                  packet->payload_length, DMA_TO_DEVICE);
2575 
2576         log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
2577         driver_data->packet = NULL;
2578         packet->ack = RCODE_CANCELLED;
2579         packet->callback(packet, &ohci->card, packet->ack);
2580         ret = 0;
2581  out:
2582         tasklet_enable(&ctx->tasklet);
2583 
2584         return ret;
2585 }
2586 
2587 static int ohci_enable_phys_dma(struct fw_card *card,
2588                                 int node_id, int generation)
2589 {
2590         struct fw_ohci *ohci = fw_ohci(card);
2591         unsigned long flags;
2592         int n, ret = 0;
2593 
2594         if (param_remote_dma)
2595                 return 0;
2596 
2597         /*
2598          * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2599          * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2600          */
2601 
2602         spin_lock_irqsave(&ohci->lock, flags);
2603 
2604         if (ohci->generation != generation) {
2605                 ret = -ESTALE;
2606                 goto out;
2607         }
2608 
2609         /*
2610          * Note, if the node ID contains a non-local bus ID, physical DMA is
2611          * enabled for _all_ nodes on remote buses.
2612          */
2613 
2614         n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2615         if (n < 32)
2616                 reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2617         else
2618                 reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2619 
2620         flush_writes(ohci);
2621  out:
2622         spin_unlock_irqrestore(&ohci->lock, flags);
2623 
2624         return ret;
2625 }
2626 
2627 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2628 {
2629         struct fw_ohci *ohci = fw_ohci(card);
2630         unsigned long flags;
2631         u32 value;
2632 
2633         switch (csr_offset) {
2634         case CSR_STATE_CLEAR:
2635         case CSR_STATE_SET:
2636                 if (ohci->is_root &&
2637                     (reg_read(ohci, OHCI1394_LinkControlSet) &
2638                      OHCI1394_LinkControl_cycleMaster))
2639                         value = CSR_STATE_BIT_CMSTR;
2640                 else
2641                         value = 0;
2642                 if (ohci->csr_state_setclear_abdicate)
2643                         value |= CSR_STATE_BIT_ABDICATE;
2644 
2645                 return value;
2646 
2647         case CSR_NODE_IDS:
2648                 return reg_read(ohci, OHCI1394_NodeID) << 16;
2649 
2650         case CSR_CYCLE_TIME:
2651                 return get_cycle_time(ohci);
2652 
2653         case CSR_BUS_TIME:
2654                 /*
2655                  * We might be called just after the cycle timer has wrapped
2656                  * around but just before the cycle64Seconds handler, so we
2657                  * better check here, too, if the bus time needs to be updated.
2658                  */
2659                 spin_lock_irqsave(&ohci->lock, flags);
2660                 value = update_bus_time(ohci);
2661                 spin_unlock_irqrestore(&ohci->lock, flags);
2662                 return value;
2663 
2664         case CSR_BUSY_TIMEOUT:
2665                 value = reg_read(ohci, OHCI1394_ATRetries);
2666                 return (value >> 4) & 0x0ffff00f;
2667 
2668         case CSR_PRIORITY_BUDGET:
2669                 return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2670                         (ohci->pri_req_max << 8);
2671 
2672         default:
2673                 WARN_ON(1);
2674                 return 0;
2675         }
2676 }
2677 
2678 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2679 {
2680         struct fw_ohci *ohci = fw_ohci(card);
2681         unsigned long flags;
2682 
2683         switch (csr_offset) {
2684         case CSR_STATE_CLEAR:
2685                 if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2686                         reg_write(ohci, OHCI1394_LinkControlClear,
2687                                   OHCI1394_LinkControl_cycleMaster);
2688                         flush_writes(ohci);
2689                 }
2690                 if (value & CSR_STATE_BIT_ABDICATE)
2691                         ohci->csr_state_setclear_abdicate = false;
2692                 break;
2693 
2694         case CSR_STATE_SET:
2695                 if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2696                         reg_write(ohci, OHCI1394_LinkControlSet,
2697                                   OHCI1394_LinkControl_cycleMaster);
2698                         flush_writes(ohci);
2699                 }
2700                 if (value & CSR_STATE_BIT_ABDICATE)
2701                         ohci->csr_state_setclear_abdicate = true;
2702                 break;
2703 
2704         case CSR_NODE_IDS:
2705                 reg_write(ohci, OHCI1394_NodeID, value >> 16);
2706                 flush_writes(ohci);
2707                 break;
2708 
2709         case CSR_CYCLE_TIME:
2710                 reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2711                 reg_write(ohci, OHCI1394_IntEventSet,
2712                           OHCI1394_cycleInconsistent);
2713                 flush_writes(ohci);
2714                 break;
2715 
2716         case CSR_BUS_TIME:
2717                 spin_lock_irqsave(&ohci->lock, flags);
2718                 ohci->bus_time = (update_bus_time(ohci) & 0x40) |
2719                                  (value & ~0x7f);
2720                 spin_unlock_irqrestore(&ohci->lock, flags);
2721                 break;
2722 
2723         case CSR_BUSY_TIMEOUT:
2724                 value = (value & 0xf) | ((value & 0xf) << 4) |
2725                         ((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2726                 reg_write(ohci, OHCI1394_ATRetries, value);
2727                 flush_writes(ohci);
2728                 break;
2729 
2730         case CSR_PRIORITY_BUDGET:
2731                 reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2732                 flush_writes(ohci);
2733                 break;
2734 
2735         default:
2736                 WARN_ON(1);
2737                 break;
2738         }
2739 }
2740 
2741 static void flush_iso_completions(struct iso_context *ctx)
2742 {
2743         ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
2744                               ctx->header_length, ctx->header,
2745                               ctx->base.callback_data);
2746         ctx->header_length = 0;
2747 }
2748 
2749 static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
2750 {
2751         u32 *ctx_hdr;
2752 
2753         if (ctx->header_length + ctx->base.header_size > PAGE_SIZE) {
2754                 if (ctx->base.drop_overflow_headers)
2755                         return;
2756                 flush_iso_completions(ctx);
2757         }
2758 
2759         ctx_hdr = ctx->header + ctx->header_length;
2760         ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
2761 
2762         /*
2763          * The two iso header quadlets are byteswapped to little
2764          * endian by the controller, but we want to present them
2765          * as big endian for consistency with the bus endianness.
2766          */
2767         if (ctx->base.header_size > 0)
2768                 ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
2769         if (ctx->base.header_size > 4)
2770                 ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
2771         if (ctx->base.header_size > 8)
2772                 memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
2773         ctx->header_length += ctx->base.header_size;
2774 }
2775 
2776 static int handle_ir_packet_per_buffer(struct context *context,
2777                                        struct descriptor *d,
2778                                        struct descriptor *last)
2779 {
2780         struct iso_context *ctx =
2781                 container_of(context, struct iso_context, context);
2782         struct descriptor *pd;
2783         u32 buffer_dma;
2784 
2785         for (pd = d; pd <= last; pd++)
2786                 if (pd->transfer_status)
2787                         break;
2788         if (pd > last)
2789                 /* Descriptor(s) not done yet, stop iteration */
2790                 return 0;
2791 
2792         while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
2793                 d++;
2794                 buffer_dma = le32_to_cpu(d->data_address);
2795                 dma_sync_single_range_for_cpu(context->ohci->card.device,
2796                                               buffer_dma & PAGE_MASK,
2797                                               buffer_dma & ~PAGE_MASK,
2798                                               le16_to_cpu(d->req_count),
2799                                               DMA_FROM_DEVICE);
2800         }
2801 
2802         copy_iso_headers(ctx, (u32 *) (last + 1));
2803 
2804         if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2805                 flush_iso_completions(ctx);
2806 
2807         return 1;
2808 }
2809 
2810 /* d == last because each descriptor block is only a single descriptor. */
2811 static int handle_ir_buffer_fill(struct context *context,
2812                                  struct descriptor *d,
2813                                  struct descriptor *last)
2814 {
2815         struct iso_context *ctx =
2816                 container_of(context, struct iso_context, context);
2817         unsigned int req_count, res_count, completed;
2818         u32 buffer_dma;
2819 
2820         req_count = le16_to_cpu(last->req_count);
2821         res_count = le16_to_cpu(ACCESS_ONCE(last->res_count));
2822         completed = req_count - res_count;
2823         buffer_dma = le32_to_cpu(last->data_address);
2824 
2825         if (completed > 0) {
2826                 ctx->mc_buffer_bus = buffer_dma;
2827                 ctx->mc_completed = completed;
2828         }
2829 
2830         if (res_count != 0)
2831                 /* Descriptor(s) not done yet, stop iteration */
2832                 return 0;
2833 
2834         dma_sync_single_range_for_cpu(context->ohci->card.device,
2835                                       buffer_dma & PAGE_MASK,
2836                                       buffer_dma & ~PAGE_MASK,
2837                                       completed, DMA_FROM_DEVICE);
2838 
2839         if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
2840                 ctx->base.callback.mc(&ctx->base,
2841                                       buffer_dma + completed,
2842                                       ctx->base.callback_data);
2843                 ctx->mc_completed = 0;
2844         }
2845 
2846         return 1;
2847 }
2848 
2849 static void flush_ir_buffer_fill(struct iso_context *ctx)
2850 {
2851         dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
2852                                       ctx->mc_buffer_bus & PAGE_MASK,
2853                                       ctx->mc_buffer_bus & ~PAGE_MASK,
2854                                       ctx->mc_completed, DMA_FROM_DEVICE);
2855 
2856         ctx->base.callback.mc(&ctx->base,
2857                               ctx->mc_buffer_bus + ctx->mc_completed,
2858                               ctx->base.callback_data);
2859         ctx->mc_completed = 0;
2860 }
2861 
2862 static inline void sync_it_packet_for_cpu(struct context *context,
2863                                           struct descriptor *pd)
2864 {
2865         __le16 control;
2866         u32 buffer_dma;
2867 
2868         /* only packets beginning with OUTPUT_MORE* have data buffers */
2869         if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2870                 return;
2871 
2872         /* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
2873         pd += 2;
2874 
2875         /*
2876          * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
2877          * data buffer is in the context program's coherent page and must not
2878          * be synced.
2879          */
2880         if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
2881             (context->current_bus          & PAGE_MASK)) {
2882                 if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
2883                         return;
2884                 pd++;
2885         }
2886 
2887         do {
2888                 buffer_dma = le32_to_cpu(pd->data_address);
2889                 dma_sync_single_range_for_cpu(context->ohci->card.device,
2890                                               buffer_dma & PAGE_MASK,
2891                                               buffer_dma & ~PAGE_MASK,
2892                                               le16_to_cpu(pd->req_count),
2893                                               DMA_TO_DEVICE);
2894                 control = pd->control;
2895                 pd++;
2896         } while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
2897 }
2898 
2899 static int handle_it_packet(struct context *context,
2900                             struct descriptor *d,
2901                             struct descriptor *last)
2902 {
2903         struct iso_context *ctx =
2904                 container_of(context, struct iso_context, context);
2905         struct descriptor *pd;
2906         __be32 *ctx_hdr;
2907 
2908         for (pd = d; pd <= last; pd++)
2909                 if (pd->transfer_status)
2910                         break;
2911         if (pd > last)
2912                 /* Descriptor(s) not done yet, stop iteration */
2913                 return 0;
2914 
2915         sync_it_packet_for_cpu(context, d);
2916 
2917         if (ctx->header_length + 4 > PAGE_SIZE) {
2918                 if (ctx->base.drop_overflow_headers)
2919                         return 1;
2920                 flush_iso_completions(ctx);
2921         }
2922 
2923         ctx_hdr = ctx->header + ctx->header_length;
2924         ctx->last_timestamp = le16_to_cpu(last->res_count);
2925         /* Present this value as big-endian to match the receive code */
2926         *ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
2927                                le16_to_cpu(pd->res_count));
2928         ctx->header_length += 4;
2929 
2930         if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
2931                 flush_iso_completions(ctx);
2932 
2933         return 1;
2934 }
2935 
2936 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2937 {
2938         u32 hi = channels >> 32, lo = channels;
2939 
2940         reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2941         reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2942         reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2943         reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2944         mmiowb();
2945         ohci->mc_channels = channels;
2946 }
2947 
2948 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2949                                 int type, int channel, size_t header_size)
2950 {
2951         struct fw_ohci *ohci = fw_ohci(card);
2952         struct iso_context *uninitialized_var(ctx);
2953         descriptor_callback_t uninitialized_var(callback);
2954         u64 *uninitialized_var(channels);
2955         u32 *uninitialized_var(mask), uninitialized_var(regs);
2956         int index, ret = -EBUSY;
2957 
2958         spin_lock_irq(&ohci->lock);
2959 
2960         switch (type) {
2961         case FW_ISO_CONTEXT_TRANSMIT:
2962                 mask     = &ohci->it_context_mask;
2963                 callback = handle_it_packet;
2964                 index    = ffs(*mask) - 1;
2965                 if (index >= 0) {
2966                         *mask &= ~(1 << index);
2967                         regs = OHCI1394_IsoXmitContextBase(index);
2968                         ctx  = &ohci->it_context_list[index];
2969                 }
2970                 break;
2971 
2972         case FW_ISO_CONTEXT_RECEIVE:
2973                 channels = &ohci->ir_context_channels;
2974                 mask     = &ohci->ir_context_mask;
2975                 callback = handle_ir_packet_per_buffer;
2976                 index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2977                 if (index >= 0) {
2978                         *channels &= ~(1ULL << channel);
2979                         *mask     &= ~(1 << index);
2980                         regs = OHCI1394_IsoRcvContextBase(index);
2981                         ctx  = &ohci->ir_context_list[index];
2982                 }
2983                 break;
2984 
2985         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2986                 mask     = &ohci->ir_context_mask;
2987                 callback = handle_ir_buffer_fill;
2988                 index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2989                 if (index >= 0) {
2990                         ohci->mc_allocated = true;
2991                         *mask &= ~(1 << index);
2992                         regs = OHCI1394_IsoRcvContextBase(index);
2993                         ctx  = &ohci->ir_context_list[index];
2994                 }
2995                 break;
2996 
2997         default:
2998                 index = -1;
2999                 ret = -ENOSYS;
3000         }
3001 
3002         spin_unlock_irq(&ohci->lock);
3003 
3004         if (index < 0)
3005                 return ERR_PTR(ret);
3006 
3007         memset(ctx, 0, sizeof(*ctx));
3008         ctx->header_length = 0;
3009         ctx->header = (void *) __get_free_page(GFP_KERNEL);
3010         if (ctx->header == NULL) {
3011                 ret = -ENOMEM;
3012                 goto out;
3013         }
3014         ret = context_init(&ctx->context, ohci, regs, callback);
3015         if (ret < 0)
3016                 goto out_with_header;
3017 
3018         if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
3019                 set_multichannel_mask(ohci, 0);
3020                 ctx->mc_completed = 0;
3021         }
3022 
3023         return &ctx->base;
3024 
3025  out_with_header:
3026         free_page((unsigned long)ctx->header);
3027  out:
3028         spin_lock_irq(&ohci->lock);
3029 
3030         switch (type) {
3031         case FW_ISO_CONTEXT_RECEIVE:
3032                 *channels |= 1ULL << channel;
3033                 break;
3034 
3035         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3036                 ohci->mc_allocated = false;
3037                 break;
3038         }
3039         *mask |= 1 << index;
3040 
3041         spin_unlock_irq(&ohci->lock);
3042 
3043         return ERR_PTR(ret);
3044 }
3045 
3046 static int ohci_start_iso(struct fw_iso_context *base,
3047                           s32 cycle, u32 sync, u32 tags)
3048 {
3049         struct iso_context *ctx = container_of(base, struct iso_context, base);
3050         struct fw_ohci *ohci = ctx->context.ohci;
3051         u32 control = IR_CONTEXT_ISOCH_HEADER, match;
3052         int index;
3053 
3054         /* the controller cannot start without any queued packets */
3055         if (ctx->context.last->branch_address == 0)
3056                 return -ENODATA;
3057 
3058         switch (ctx->base.type) {
3059         case FW_ISO_CONTEXT_TRANSMIT:
3060                 index = ctx - ohci->it_context_list;
3061                 match = 0;
3062                 if (cycle >= 0)
3063                         match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
3064                                 (cycle & 0x7fff) << 16;
3065 
3066                 reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
3067                 reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
3068                 context_run(&ctx->context, match);
3069                 break;
3070 
3071         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3072                 control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
3073                 /* fall through */
3074         case FW_ISO_CONTEXT_RECEIVE:
3075                 index = ctx - ohci->ir_context_list;
3076                 match = (tags << 28) | (sync << 8) | ctx->base.channel;
3077                 if (cycle >= 0) {
3078                         match |= (cycle & 0x07fff) << 12;
3079                         control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
3080                 }
3081 
3082                 reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
3083                 reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
3084                 reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
3085                 context_run(&ctx->context, control);
3086 
3087                 ctx->sync = sync;
3088                 ctx->tags = tags;
3089 
3090                 break;
3091         }
3092 
3093         return 0;
3094 }
3095 
3096 static int ohci_stop_iso(struct fw_iso_context *base)
3097 {
3098         struct fw_ohci *ohci = fw_ohci(base->card);
3099         struct iso_context *ctx = container_of(base, struct iso_context, base);
3100         int index;
3101 
3102         switch (ctx->base.type) {
3103         case FW_ISO_CONTEXT_TRANSMIT:
3104                 index = ctx - ohci->it_context_list;
3105                 reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
3106                 break;
3107 
3108         case FW_ISO_CONTEXT_RECEIVE:
3109         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3110                 index = ctx - ohci->ir_context_list;
3111                 reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
3112                 break;
3113         }
3114         flush_writes(ohci);
3115         context_stop(&ctx->context);
3116         tasklet_kill(&ctx->context.tasklet);
3117 
3118         return 0;
3119 }
3120 
3121 static void ohci_free_iso_context(struct fw_iso_context *base)
3122 {
3123         struct fw_ohci *ohci = fw_ohci(base->card);
3124         struct iso_context *ctx = container_of(base, struct iso_context, base);
3125         unsigned long flags;
3126         int index;
3127 
3128         ohci_stop_iso(base);
3129         context_release(&ctx->context);
3130         free_page((unsigned long)ctx->header);
3131 
3132         spin_lock_irqsave(&ohci->lock, flags);
3133 
3134         switch (base->type) {
3135         case FW_ISO_CONTEXT_TRANSMIT:
3136                 index = ctx - ohci->it_context_list;
3137                 ohci->it_context_mask |= 1 << index;
3138                 break;
3139 
3140         case FW_ISO_CONTEXT_RECEIVE:
3141                 index = ctx - ohci->ir_context_list;
3142                 ohci->ir_context_mask |= 1 << index;
3143                 ohci->ir_context_channels |= 1ULL << base->channel;
3144                 break;
3145 
3146         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3147                 index = ctx - ohci->ir_context_list;
3148                 ohci->ir_context_mask |= 1 << index;
3149                 ohci->ir_context_channels |= ohci->mc_channels;
3150                 ohci->mc_channels = 0;
3151                 ohci->mc_allocated = false;
3152                 break;
3153         }
3154 
3155         spin_unlock_irqrestore(&ohci->lock, flags);
3156 }
3157 
3158 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
3159 {
3160         struct fw_ohci *ohci = fw_ohci(base->card);
3161         unsigned long flags;
3162         int ret;
3163 
3164         switch (base->type) {
3165         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3166 
3167                 spin_lock_irqsave(&ohci->lock, flags);
3168 
3169                 /* Don't allow multichannel to grab other contexts' channels. */
3170                 if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
3171                         *channels = ohci->ir_context_channels;
3172                         ret = -EBUSY;
3173                 } else {
3174                         set_multichannel_mask(ohci, *channels);
3175                         ret = 0;
3176                 }
3177 
3178                 spin_unlock_irqrestore(&ohci->lock, flags);
3179 
3180                 break;
3181         default:
3182                 ret = -EINVAL;
3183         }
3184 
3185         return ret;
3186 }
3187 
3188 #ifdef CONFIG_PM
3189 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
3190 {
3191         int i;
3192         struct iso_context *ctx;
3193 
3194         for (i = 0 ; i < ohci->n_ir ; i++) {
3195                 ctx = &ohci->ir_context_list[i];
3196                 if (ctx->context.running)
3197                         ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3198         }
3199 
3200         for (i = 0 ; i < ohci->n_it ; i++) {
3201                 ctx = &ohci->it_context_list[i];
3202                 if (ctx->context.running)
3203                         ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
3204         }
3205 }
3206 #endif
3207 
3208 static int queue_iso_transmit(struct iso_context *ctx,
3209                               struct fw_iso_packet *packet,
3210                               struct fw_iso_buffer *buffer,
3211                               unsigned long payload)
3212 {
3213         struct descriptor *d, *last, *pd;
3214         struct fw_iso_packet *p;
3215         __le32 *header;
3216         dma_addr_t d_bus, page_bus;
3217         u32 z, header_z, payload_z, irq;
3218         u32 payload_index, payload_end_index, next_page_index;
3219         int page, end_page, i, length, offset;
3220 
3221         p = packet;
3222         payload_index = payload;
3223 
3224         if (p->skip)
3225                 z = 1;
3226         else
3227                 z = 2;
3228         if (p->header_length > 0)
3229                 z++;
3230 
3231         /* Determine the first page the payload isn't contained in. */
3232         end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
3233         if (p->payload_length > 0)
3234                 payload_z = end_page - (payload_index >> PAGE_SHIFT);
3235         else
3236                 payload_z = 0;
3237 
3238         z += payload_z;
3239 
3240         /* Get header size in number of descriptors. */
3241         header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
3242 
3243         d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
3244         if (d == NULL)
3245                 return -ENOMEM;
3246 
3247         if (!p->skip) {
3248                 d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
3249                 d[0].req_count = cpu_to_le16(8);
3250                 /*
3251                  * Link the skip address to this descriptor itself.  This causes
3252                  * a context to skip a cycle whenever lost cycles or FIFO
3253                  * overruns occur, without dropping the data.  The application
3254                  * should then decide whether this is an error condition or not.
3255                  * FIXME:  Make the context's cycle-lost behaviour configurable?
3256                  */
3257                 d[0].branch_address = cpu_to_le32(d_bus | z);
3258 
3259                 header = (__le32 *) &d[1];
3260                 header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
3261                                         IT_HEADER_TAG(p->tag) |
3262                                         IT_HEADER_TCODE(TCODE_STREAM_DATA) |
3263                                         IT_HEADER_CHANNEL(ctx->base.channel) |
3264                                         IT_HEADER_SPEED(ctx->base.speed));
3265                 header[1] =
3266                         cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
3267                                                           p->payload_length));
3268         }
3269 
3270         if (p->header_length > 0) {
3271                 d[2].req_count    = cpu_to_le16(p->header_length);
3272                 d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
3273                 memcpy(&d[z], p->header, p->header_length);
3274         }
3275 
3276         pd = d + z - payload_z;
3277         payload_end_index = payload_index + p->payload_length;
3278         for (i = 0; i < payload_z; i++) {
3279                 page               = payload_index >> PAGE_SHIFT;
3280                 offset             = payload_index & ~PAGE_MASK;
3281                 next_page_index    = (page + 1) << PAGE_SHIFT;
3282                 length             =
3283                         min(next_page_index, payload_end_index) - payload_index;
3284                 pd[i].req_count    = cpu_to_le16(length);
3285 
3286                 page_bus = page_private(buffer->pages[page]);
3287                 pd[i].data_address = cpu_to_le32(page_bus + offset);
3288 
3289                 dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3290                                                  page_bus, offset, length,
3291                                                  DMA_TO_DEVICE);
3292 
3293                 payload_index += length;
3294         }
3295 
3296         if (p->interrupt)
3297                 irq = DESCRIPTOR_IRQ_ALWAYS;
3298         else
3299                 irq = DESCRIPTOR_NO_IRQ;
3300 
3301         last = z == 2 ? d : d + z - 1;
3302         last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
3303                                      DESCRIPTOR_STATUS |
3304                                      DESCRIPTOR_BRANCH_ALWAYS |
3305                                      irq);
3306 
3307         context_append(&ctx->context, d, z, header_z);
3308 
3309         return 0;
3310 }
3311 
3312 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
3313                                        struct fw_iso_packet *packet,
3314                                        struct fw_iso_buffer *buffer,
3315                                        unsigned long payload)
3316 {
3317         struct device *device = ctx->context.ohci->card.device;
3318         struct descriptor *d, *pd;
3319         dma_addr_t d_bus, page_bus;
3320         u32 z, header_z, rest;
3321         int i, j, length;
3322         int page, offset, packet_count, header_size, payload_per_buffer;
3323 
3324         /*
3325          * The OHCI controller puts the isochronous header and trailer in the
3326          * buffer, so we need at least 8 bytes.
3327          */
3328         packet_count = packet->header_length / ctx->base.header_size;
3329         header_size  = max(ctx->base.header_size, (size_t)8);
3330 
3331         /* Get header size in number of descriptors. */
3332         header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3333         page     = payload >> PAGE_SHIFT;
3334         offset   = payload & ~PAGE_MASK;
3335         payload_per_buffer = packet->payload_length / packet_count;
3336 
3337         for (i = 0; i < packet_count; i++) {
3338                 /* d points to the header descriptor */
3339                 z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3340                 d = context_get_descriptors(&ctx->context,
3341                                 z + header_z, &d_bus);
3342                 if (d == NULL)
3343                         return -ENOMEM;
3344 
3345                 d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3346                                               DESCRIPTOR_INPUT_MORE);
3347                 if (packet->skip && i == 0)
3348                         d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3349                 d->req_count    = cpu_to_le16(header_size);
3350                 d->res_count    = d->req_count;
3351                 d->transfer_status = 0;
3352                 d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3353 
3354                 rest = payload_per_buffer;
3355                 pd = d;
3356                 for (j = 1; j < z; j++) {
3357                         pd++;
3358                         pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3359                                                   DESCRIPTOR_INPUT_MORE);
3360 
3361                         if (offset + rest < PAGE_SIZE)
3362                                 length = rest;
3363                         else
3364                                 length = PAGE_SIZE - offset;
3365                         pd->req_count = cpu_to_le16(length);
3366                         pd->res_count = pd->req_count;
3367                         pd->transfer_status = 0;
3368 
3369                         page_bus = page_private(buffer->pages[page]);
3370                         pd->data_address = cpu_to_le32(page_bus + offset);
3371 
3372                         dma_sync_single_range_for_device(device, page_bus,
3373                                                          offset, length,
3374                                                          DMA_FROM_DEVICE);
3375 
3376                         offset = (offset + length) & ~PAGE_MASK;
3377                         rest -= length;
3378                         if (offset == 0)
3379                                 page++;
3380                 }
3381                 pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3382                                           DESCRIPTOR_INPUT_LAST |
3383                                           DESCRIPTOR_BRANCH_ALWAYS);
3384                 if (packet->interrupt && i == packet_count - 1)
3385                         pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3386 
3387                 context_append(&ctx->context, d, z, header_z);
3388         }
3389 
3390         return 0;
3391 }
3392 
3393 static int queue_iso_buffer_fill(struct iso_context *ctx,
3394                                  struct fw_iso_packet *packet,
3395                                  struct fw_iso_buffer *buffer,
3396                                  unsigned long payload)
3397 {
3398         struct descriptor *d;
3399         dma_addr_t d_bus, page_bus;
3400         int page, offset, rest, z, i, length;
3401 
3402         page   = payload >> PAGE_SHIFT;
3403         offset = payload & ~PAGE_MASK;
3404         rest   = packet->payload_length;
3405 
3406         /* We need one descriptor for each page in the buffer. */
3407         z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3408 
3409         if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3410                 return -EFAULT;
3411 
3412         for (i = 0; i < z; i++) {
3413                 d = context_get_descriptors(&ctx->context, 1, &d_bus);
3414                 if (d == NULL)
3415                         return -ENOMEM;
3416 
3417                 d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3418                                          DESCRIPTOR_BRANCH_ALWAYS);
3419                 if (packet->skip && i == 0)
3420                         d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3421                 if (packet->interrupt && i == z - 1)
3422                         d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3423 
3424                 if (offset + rest < PAGE_SIZE)
3425                         length = rest;
3426                 else
3427                         length = PAGE_SIZE - offset;
3428                 d->req_count = cpu_to_le16(length);
3429                 d->res_count = d->req_count;
3430                 d->transfer_status = 0;
3431 
3432                 page_bus = page_private(buffer->pages[page]);
3433                 d->data_address = cpu_to_le32(page_bus + offset);
3434 
3435                 dma_sync_single_range_for_device(ctx->context.ohci->card.device,
3436                                                  page_bus, offset, length,
3437                                                  DMA_FROM_DEVICE);
3438 
3439                 rest -= length;
3440                 offset = 0;
3441                 page++;
3442 
3443                 context_append(&ctx->context, d, 1, 0);
3444         }
3445 
3446         return 0;
3447 }
3448 
3449 static int ohci_queue_iso(struct fw_iso_context *base,
3450                           struct fw_iso_packet *packet,
3451                           struct fw_iso_buffer *buffer,
3452                           unsigned long payload)
3453 {
3454         struct iso_context *ctx = container_of(base, struct iso_context, base);
3455         unsigned long flags;
3456         int ret = -ENOSYS;
3457 
3458         spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3459         switch (base->type) {
3460         case FW_ISO_CONTEXT_TRANSMIT:
3461                 ret = queue_iso_transmit(ctx, packet, buffer, payload);
3462                 break;
3463         case FW_ISO_CONTEXT_RECEIVE:
3464                 ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3465                 break;
3466         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3467                 ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3468                 break;
3469         }
3470         spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3471 
3472         return ret;
3473 }
3474 
3475 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3476 {
3477         struct context *ctx =
3478                         &container_of(base, struct iso_context, base)->context;
3479 
3480         reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3481 }
3482 
3483 static int ohci_flush_iso_completions(struct fw_iso_context *base)
3484 {
3485         struct iso_context *ctx = container_of(base, struct iso_context, base);
3486         int ret = 0;
3487 
3488         tasklet_disable(&ctx->context.tasklet);
3489 
3490         if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
3491                 context_tasklet((unsigned long)&ctx->context);
3492 
3493                 switch (base->type) {
3494                 case FW_ISO_CONTEXT_TRANSMIT:
3495                 case FW_ISO_CONTEXT_RECEIVE:
3496                         if (ctx->header_length != 0)
3497                                 flush_iso_completions(ctx);
3498                         break;
3499                 case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3500                         if (ctx->mc_completed != 0)
3501                                 flush_ir_buffer_fill(ctx);
3502                         break;
3503                 default:
3504                         ret = -ENOSYS;
3505                 }
3506 
3507                 clear_bit_unlock(0, &ctx->flushing_completions);
3508                 smp_mb__after_atomic();
3509         }
3510 
3511         tasklet_enable(&ctx->context.tasklet);
3512 
3513         return ret;
3514 }
3515 
3516 static const struct fw_card_driver ohci_driver = {
3517         .enable                 = ohci_enable,
3518         .read_phy_reg           = ohci_read_phy_reg,
3519         .update_phy_reg         = ohci_update_phy_reg,
3520         .set_config_rom         = ohci_set_config_rom,
3521         .send_request           = ohci_send_request,
3522         .send_response          = ohci_send_response,
3523         .cancel_packet          = ohci_cancel_packet,
3524         .enable_phys_dma        = ohci_enable_phys_dma,
3525         .read_csr               = ohci_read_csr,
3526         .write_csr              = ohci_write_csr,
3527 
3528         .allocate_iso_context   = ohci_allocate_iso_context,
3529         .free_iso_context       = ohci_free_iso_context,
3530         .set_iso_channels       = ohci_set_iso_channels,
3531         .queue_iso              = ohci_queue_iso,
3532         .flush_queue_iso        = ohci_flush_queue_iso,
3533         .flush_iso_completions  = ohci_flush_iso_completions,
3534         .start_iso              = ohci_start_iso,
3535         .stop_iso               = ohci_stop_iso,
3536 };
3537 
3538 #ifdef CONFIG_PPC_PMAC
3539 static void pmac_ohci_on(struct pci_dev *dev)
3540 {
3541         if (machine_is(powermac)) {
3542                 struct device_node *ofn = pci_device_to_OF_node(dev);
3543 
3544                 if (ofn) {
3545                         pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3546                         pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3547                 }
3548         }
3549 }
3550 
3551 static void pmac_ohci_off(struct pci_dev *dev)
3552 {
3553         if (machine_is(powermac)) {
3554                 struct device_node *ofn = pci_device_to_OF_node(dev);
3555 
3556                 if (ofn) {
3557                         pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3558                         pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3559                 }
3560         }
3561 }
3562 #else
3563 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3564 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3565 #endif /* CONFIG_PPC_PMAC */
3566 
3567 static int pci_probe(struct pci_dev *dev,
3568                                const struct pci_device_id *ent)
3569 {
3570         struct fw_ohci *ohci;
3571         u32 bus_options, max_receive, link_speed, version;
3572         u64 guid;
3573         int i, err;
3574         size_t size;
3575 
3576         if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3577                 dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3578                 return -ENOSYS;
3579         }
3580 
3581         ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3582         if (ohci == NULL) {
3583                 err = -ENOMEM;
3584                 goto fail;
3585         }
3586 
3587         fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3588 
3589         pmac_ohci_on(dev);
3590 
3591         err = pci_enable_device(dev);
3592         if (err) {
3593                 dev_err(&dev->dev, "failed to enable OHCI hardware\n");
3594                 goto fail_free;
3595         }
3596 
3597         pci_set_master(dev);
3598         pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3599         pci_set_drvdata(dev, ohci);
3600 
3601         spin_lock_init(&ohci->lock);
3602         mutex_init(&ohci->phy_reg_mutex);
3603 
3604         INIT_WORK(&ohci->bus_reset_work, bus_reset_work);
3605 
3606         if (!(pci_resource_flags(dev, 0) & IORESOURCE_MEM) ||
3607             pci_resource_len(dev, 0) < OHCI1394_REGISTER_SIZE) {
3608                 ohci_err(ohci, "invalid MMIO resource\n");
3609                 err = -ENXIO;
3610                 goto fail_disable;
3611         }
3612 
3613         err = pci_request_region(dev, 0, ohci_driver_name);
3614         if (err) {
3615                 ohci_err(ohci, "MMIO resource unavailable\n");
3616                 goto fail_disable;
3617         }
3618 
3619         ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3620         if (ohci->registers == NULL) {
3621                 ohci_err(ohci, "failed to remap registers\n");
3622                 err = -ENXIO;
3623                 goto fail_iomem;
3624         }
3625 
3626         for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3627                 if ((ohci_quirks[i].vendor == dev->vendor) &&
3628                     (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3629                      ohci_quirks[i].device == dev->device) &&
3630                     (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3631                      ohci_quirks[i].revision >= dev->revision)) {
3632                         ohci->quirks = ohci_quirks[i].flags;
3633                         break;
3634                 }
3635         if (param_quirks)
3636                 ohci->quirks = param_quirks;
3637 
3638         /*
3639          * Because dma_alloc_coherent() allocates at least one page,
3640          * we save space by using a common buffer for the AR request/
3641          * response descriptors and the self IDs buffer.
3642          */
3643         BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3644         BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3645         ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3646                                                PAGE_SIZE,
3647                                                &ohci->misc_buffer_bus,
3648                                                GFP_KERNEL);
3649         if (!ohci->misc_buffer) {
3650                 err = -ENOMEM;
3651                 goto fail_iounmap;
3652         }
3653 
3654         err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3655                               OHCI1394_AsReqRcvContextControlSet);
3656         if (err < 0)
3657                 goto fail_misc_buf;
3658 
3659         err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3660                               OHCI1394_AsRspRcvContextControlSet);
3661         if (err < 0)
3662                 goto fail_arreq_ctx;
3663 
3664         err = context_init(&ohci->at_request_ctx, ohci,
3665                            OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3666         if (err < 0)
3667                 goto fail_arrsp_ctx;
3668 
3669         err = context_init(&ohci->at_response_ctx, ohci,
3670                            OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3671         if (err < 0)
3672                 goto fail_atreq_ctx;
3673 
3674         reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3675         ohci->ir_context_channels = ~0ULL;
3676         ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3677         reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3678         ohci->ir_context_mask = ohci->ir_context_support;
3679         ohci->n_ir = hweight32(ohci->ir_context_mask);
3680         size = sizeof(struct iso_context) * ohci->n_ir;
3681         ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3682 
3683         reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3684         ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3685         reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3686         ohci->it_context_mask = ohci->it_context_support;
3687         ohci->n_it = hweight32(ohci->it_context_mask);
3688         size = sizeof(struct iso_context) * ohci->n_it;
3689         ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3690 
3691         if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3692                 err = -ENOMEM;
3693                 goto fail_contexts;
3694         }
3695 
3696         ohci->self_id     = ohci->misc_buffer     + PAGE_SIZE/2;
3697         ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3698 
3699         bus_options = reg_read(ohci, OHCI1394_BusOptions);
3700         max_receive = (bus_options >> 12) & 0xf;
3701         link_speed = bus_options & 0x7;
3702         guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3703                 reg_read(ohci, OHCI1394_GUIDLo);
3704 
3705         if (!(ohci->quirks & QUIRK_NO_MSI))
3706                 pci_enable_msi(dev);
3707         if (request_irq(dev->irq, irq_handler,
3708                         pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
3709                         ohci_driver_name, ohci)) {
3710                 ohci_err(ohci, "failed to allocate interrupt %d\n", dev->irq);
3711                 err = -EIO;
3712                 goto fail_msi;
3713         }
3714 
3715         err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3716         if (err)
3717                 goto fail_irq;
3718 
3719         version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3720         ohci_notice(ohci,
3721                     "added OHCI v%x.%x device as card %d, "
3722                     "%d IR + %d IT contexts, quirks 0x%x%s\n",
3723                     version >> 16, version & 0xff, ohci->card.index,
3724                     ohci->n_ir, ohci->n_it, ohci->quirks,
3725                     reg_read(ohci, OHCI1394_PhyUpperBound) ?
3726                         ", physUB" : "");
3727 
3728         return 0;
3729 
3730  fail_irq:
3731         free_irq(dev->irq, ohci);
3732  fail_msi:
3733         pci_disable_msi(dev);
3734  fail_contexts:
3735         kfree(ohci->ir_context_list);
3736         kfree(ohci->it_context_list);
3737         context_release(&ohci->at_response_ctx);
3738  fail_atreq_ctx:
3739         context_release(&ohci->at_request_ctx);
3740  fail_arrsp_ctx:
3741         ar_context_release(&ohci->ar_response_ctx);
3742  fail_arreq_ctx:
3743         ar_context_release(&ohci->ar_request_ctx);
3744  fail_misc_buf:
3745         dma_free_coherent(ohci->card.device, PAGE_SIZE,
3746                           ohci->misc_buffer, ohci->misc_buffer_bus);
3747  fail_iounmap:
3748         pci_iounmap(dev, ohci->registers);
3749  fail_iomem:
3750         pci_release_region(dev, 0);
3751  fail_disable:
3752         pci_disable_device(dev);
3753  fail_free:
3754         kfree(ohci);
3755         pmac_ohci_off(dev);
3756  fail:
3757         return err;
3758 }
3759 
3760 static void pci_remove(struct pci_dev *dev)
3761 {
3762         struct fw_ohci *ohci = pci_get_drvdata(dev);
3763 
3764         /*
3765          * If the removal is happening from the suspend state, LPS won't be
3766          * enabled and host registers (eg., IntMaskClear) won't be accessible.
3767          */
3768         if (reg_read(ohci, OHCI1394_HCControlSet) & OHCI1394_HCControl_LPS) {
3769                 reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3770                 flush_writes(ohci);
3771         }
3772         cancel_work_sync(&ohci->bus_reset_work);
3773         fw_core_remove_card(&ohci->card);
3774 
3775         /*
3776          * FIXME: Fail all pending packets here, now that the upper
3777          * layers can't queue any more.
3778          */
3779 
3780         software_reset(ohci);
3781         free_irq(dev->irq, ohci);
3782 
3783         if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3784                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3785                                   ohci->next_config_rom, ohci->next_config_rom_bus);
3786         if (ohci->config_rom)
3787                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3788                                   ohci->config_rom, ohci->config_rom_bus);
3789         ar_context_release(&ohci->ar_request_ctx);
3790         ar_context_release(&ohci->ar_response_ctx);
3791         dma_free_coherent(ohci->card.device, PAGE_SIZE,
3792                           ohci->misc_buffer, ohci->misc_buffer_bus);
3793         context_release(&ohci->at_request_ctx);
3794         context_release(&ohci->at_response_ctx);
3795         kfree(ohci->it_context_list);
3796         kfree(ohci->ir_context_list);
3797         pci_disable_msi(dev);
3798         pci_iounmap(dev, ohci->registers);
3799         pci_release_region(dev, 0);
3800         pci_disable_device(dev);
3801         kfree(ohci);
3802         pmac_ohci_off(dev);
3803 
3804         dev_notice(&dev->dev, "removed fw-ohci device\n");
3805 }
3806 
3807 #ifdef CONFIG_PM
3808 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3809 {
3810         struct fw_ohci *ohci = pci_get_drvdata(dev);
3811         int err;
3812 
3813         software_reset(ohci);
3814         err = pci_save_state(dev);
3815         if (err) {
3816                 ohci_err(ohci, "pci_save_state failed\n");
3817                 return err;
3818         }
3819         err = pci_set_power_state(dev, pci_choose_state(dev, state));
3820         if (err)
3821                 ohci_err(ohci, "pci_set_power_state failed with %d\n", err);
3822         pmac_ohci_off(dev);
3823 
3824         return 0;
3825 }
3826 
3827 static int pci_resume(struct pci_dev *dev)
3828 {
3829         struct fw_ohci *ohci = pci_get_drvdata(dev);
3830         int err;
3831 
3832         pmac_ohci_on(dev);
3833         pci_set_power_state(dev, PCI_D0);
3834         pci_restore_state(dev);
3835         err = pci_enable_device(dev);
3836         if (err) {
3837                 ohci_err(ohci, "pci_enable_device failed\n");
3838                 return err;
3839         }
3840 
3841         /* Some systems don't setup GUID register on resume from ram  */
3842         if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3843                                         !reg_read(ohci, OHCI1394_GUIDHi)) {
3844                 reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3845                 reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3846         }
3847 
3848         err = ohci_enable(&ohci->card, NULL, 0);
3849         if (err)
3850                 return err;
3851 
3852         ohci_resume_iso_dma(ohci);
3853 
3854         return 0;
3855 }
3856 #endif
3857 
3858 static const struct pci_device_id pci_table[] = {
3859         { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3860         { }
3861 };
3862 
3863 MODULE_DEVICE_TABLE(pci, pci_table);
3864 
3865 static struct pci_driver fw_ohci_pci_driver = {
3866         .name           = ohci_driver_name,
3867         .id_table       = pci_table,
3868         .probe          = pci_probe,
3869         .remove         = pci_remove,
3870 #ifdef CONFIG_PM
3871         .resume         = pci_resume,
3872         .suspend        = pci_suspend,
3873 #endif
3874 };
3875 
3876 static int __init fw_ohci_init(void)
3877 {
3878         selfid_workqueue = alloc_workqueue(KBUILD_MODNAME, WQ_MEM_RECLAIM, 0);
3879         if (!selfid_workqueue)
3880                 return -ENOMEM;
3881 
3882         return pci_register_driver(&fw_ohci_pci_driver);
3883 }
3884 
3885 static void __exit fw_ohci_cleanup(void)
3886 {
3887         pci_unregister_driver(&fw_ohci_pci_driver);
3888         destroy_workqueue(selfid_workqueue);
3889 }
3890 
3891 module_init(fw_ohci_init);
3892 module_exit(fw_ohci_cleanup);
3893 
3894 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3895 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3896 MODULE_LICENSE("GPL");
3897 
3898 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3899 MODULE_ALIAS("ohci1394");
3900 

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