Version:  2.0.40 2.2.26 2.4.37 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 3.17

Linux/drivers/scsi/mac_esp.c

  1 /* mac_esp.c: ESP front-end for Macintosh Quadra systems.
  2  *
  3  * Adapted from jazz_esp.c and the old mac_esp.c.
  4  *
  5  * The pseudo DMA algorithm is based on the one used in NetBSD.
  6  * See sys/arch/mac68k/obio/esp.c for some background information.
  7  *
  8  * Copyright (C) 2007-2008 Finn Thain
  9  */
 10 
 11 #include <linux/kernel.h>
 12 #include <linux/types.h>
 13 #include <linux/module.h>
 14 #include <linux/init.h>
 15 #include <linux/interrupt.h>
 16 #include <linux/platform_device.h>
 17 #include <linux/dma-mapping.h>
 18 #include <linux/scatterlist.h>
 19 #include <linux/delay.h>
 20 #include <linux/io.h>
 21 #include <linux/nubus.h>
 22 #include <linux/slab.h>
 23 
 24 #include <asm/irq.h>
 25 #include <asm/dma.h>
 26 #include <asm/macints.h>
 27 #include <asm/macintosh.h>
 28 #include <asm/mac_via.h>
 29 
 30 #include <scsi/scsi_host.h>
 31 
 32 #include "esp_scsi.h"
 33 
 34 #define DRV_MODULE_NAME     "mac_esp"
 35 #define PFX                 DRV_MODULE_NAME ": "
 36 #define DRV_VERSION         "1.000"
 37 #define DRV_MODULE_RELDATE  "Sept 15, 2007"
 38 
 39 #define MAC_ESP_IO_BASE          0x50F00000
 40 #define MAC_ESP_REGS_QUADRA      (MAC_ESP_IO_BASE + 0x10000)
 41 #define MAC_ESP_REGS_QUADRA2     (MAC_ESP_IO_BASE + 0xF000)
 42 #define MAC_ESP_REGS_QUADRA3     (MAC_ESP_IO_BASE + 0x18000)
 43 #define MAC_ESP_REGS_SPACING     0x402
 44 #define MAC_ESP_PDMA_REG         0xF9800024
 45 #define MAC_ESP_PDMA_REG_SPACING 0x4
 46 #define MAC_ESP_PDMA_IO_OFFSET   0x100
 47 
 48 #define esp_read8(REG)          mac_esp_read8(esp, REG)
 49 #define esp_write8(VAL, REG)    mac_esp_write8(esp, VAL, REG)
 50 
 51 struct mac_esp_priv {
 52         struct esp *esp;
 53         void __iomem *pdma_regs;
 54         void __iomem *pdma_io;
 55         int error;
 56 };
 57 static struct esp *esp_chips[2];
 58 
 59 #define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
 60                                platform_get_drvdata((struct platform_device *) \
 61                                                     (esp->dev)))
 62 
 63 static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
 64 {
 65         nubus_writeb(val, esp->regs + reg * 16);
 66 }
 67 
 68 static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
 69 {
 70         return nubus_readb(esp->regs + reg * 16);
 71 }
 72 
 73 /* For pseudo DMA and PIO we need the virtual address
 74  * so this address mapping is the identity mapping.
 75  */
 76 
 77 static dma_addr_t mac_esp_map_single(struct esp *esp, void *buf,
 78                                      size_t sz, int dir)
 79 {
 80         return (dma_addr_t)buf;
 81 }
 82 
 83 static int mac_esp_map_sg(struct esp *esp, struct scatterlist *sg,
 84                           int num_sg, int dir)
 85 {
 86         int i;
 87 
 88         for (i = 0; i < num_sg; i++)
 89                 sg[i].dma_address = (u32)sg_virt(&sg[i]);
 90         return num_sg;
 91 }
 92 
 93 static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr,
 94                                  size_t sz, int dir)
 95 {
 96         /* Nothing to do. */
 97 }
 98 
 99 static void mac_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
100                              int num_sg, int dir)
101 {
102         /* Nothing to do. */
103 }
104 
105 static void mac_esp_reset_dma(struct esp *esp)
106 {
107         /* Nothing to do. */
108 }
109 
110 static void mac_esp_dma_drain(struct esp *esp)
111 {
112         /* Nothing to do. */
113 }
114 
115 static void mac_esp_dma_invalidate(struct esp *esp)
116 {
117         /* Nothing to do. */
118 }
119 
120 static int mac_esp_dma_error(struct esp *esp)
121 {
122         return MAC_ESP_GET_PRIV(esp)->error;
123 }
124 
125 static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
126 {
127         struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
128         int i = 500000;
129 
130         do {
131                 if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
132                         return 0;
133 
134                 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
135                         return 1;
136 
137                 udelay(2);
138         } while (--i);
139 
140         printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
141                esp_read8(ESP_STATUS));
142         mep->error = 1;
143         return 1;
144 }
145 
146 static inline int mac_esp_wait_for_dreq(struct esp *esp)
147 {
148         struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
149         int i = 500000;
150 
151         do {
152                 if (mep->pdma_regs == NULL) {
153                         if (via2_scsi_drq_pending())
154                                 return 0;
155                 } else {
156                         if (nubus_readl(mep->pdma_regs) & 0x200)
157                                 return 0;
158                 }
159 
160                 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
161                         return 1;
162 
163                 udelay(2);
164         } while (--i);
165 
166         printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
167                esp_read8(ESP_STATUS));
168         mep->error = 1;
169         return 1;
170 }
171 
172 #define MAC_ESP_PDMA_LOOP(operands) \
173         asm volatile ( \
174              "       tstw %1                   \n" \
175              "       jbeq 20f                  \n" \
176              "1:     movew " operands "        \n" \
177              "2:     movew " operands "        \n" \
178              "3:     movew " operands "        \n" \
179              "4:     movew " operands "        \n" \
180              "5:     movew " operands "        \n" \
181              "6:     movew " operands "        \n" \
182              "7:     movew " operands "        \n" \
183              "8:     movew " operands "        \n" \
184              "9:     movew " operands "        \n" \
185              "10:    movew " operands "        \n" \
186              "11:    movew " operands "        \n" \
187              "12:    movew " operands "        \n" \
188              "13:    movew " operands "        \n" \
189              "14:    movew " operands "        \n" \
190              "15:    movew " operands "        \n" \
191              "16:    movew " operands "        \n" \
192              "       subqw #1,%1               \n" \
193              "       jbne 1b                   \n" \
194              "20:    tstw %2                   \n" \
195              "       jbeq 30f                  \n" \
196              "21:    movew " operands "        \n" \
197              "       subqw #1,%2               \n" \
198              "       jbne 21b                  \n" \
199              "30:    tstw %3                   \n" \
200              "       jbeq 40f                  \n" \
201              "31:    moveb " operands "        \n" \
202              "32:    nop                       \n" \
203              "40:                              \n" \
204              "                                 \n" \
205              "       .section __ex_table,\"a\" \n" \
206              "       .align  4                 \n" \
207              "       .long   1b,40b            \n" \
208              "       .long   2b,40b            \n" \
209              "       .long   3b,40b            \n" \
210              "       .long   4b,40b            \n" \
211              "       .long   5b,40b            \n" \
212              "       .long   6b,40b            \n" \
213              "       .long   7b,40b            \n" \
214              "       .long   8b,40b            \n" \
215              "       .long   9b,40b            \n" \
216              "       .long  10b,40b            \n" \
217              "       .long  11b,40b            \n" \
218              "       .long  12b,40b            \n" \
219              "       .long  13b,40b            \n" \
220              "       .long  14b,40b            \n" \
221              "       .long  15b,40b            \n" \
222              "       .long  16b,40b            \n" \
223              "       .long  21b,40b            \n" \
224              "       .long  31b,40b            \n" \
225              "       .long  32b,40b            \n" \
226              "       .previous                 \n" \
227              : "+a" (addr), "+r" (count32), "+r" (count2) \
228              : "g" (count1), "a" (mep->pdma_io))
229 
230 static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
231                                   u32 dma_count, int write, u8 cmd)
232 {
233         struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
234 
235         mep->error = 0;
236 
237         if (!write)
238                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
239 
240         esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
241         esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);
242 
243         scsi_esp_cmd(esp, cmd);
244 
245         do {
246                 unsigned int count32 = esp_count >> 5;
247                 unsigned int count2 = (esp_count & 0x1F) >> 1;
248                 unsigned int count1 = esp_count & 1;
249                 unsigned int start_addr = addr;
250 
251                 if (mac_esp_wait_for_dreq(esp))
252                         break;
253 
254                 if (write) {
255                         MAC_ESP_PDMA_LOOP("%4@,%0@+");
256 
257                         esp_count -= addr - start_addr;
258                 } else {
259                         unsigned int n;
260 
261                         MAC_ESP_PDMA_LOOP("%0@+,%4@");
262 
263                         if (mac_esp_wait_for_empty_fifo(esp))
264                                 break;
265 
266                         n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
267                         addr = start_addr + esp_count - n;
268                         esp_count = n;
269                 }
270         } while (esp_count);
271 }
272 
273 /*
274  * Programmed IO routines follow.
275  */
276 
277 static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp)
278 {
279         int i = 500000;
280 
281         do {
282                 unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
283 
284                 if (fbytes)
285                         return fbytes;
286 
287                 udelay(2);
288         } while (--i);
289 
290         printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n",
291                esp_read8(ESP_STATUS));
292         return 0;
293 }
294 
295 static inline int mac_esp_wait_for_intr(struct esp *esp)
296 {
297         struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
298         int i = 500000;
299 
300         do {
301                 esp->sreg = esp_read8(ESP_STATUS);
302                 if (esp->sreg & ESP_STAT_INTR)
303                         return 0;
304 
305                 udelay(2);
306         } while (--i);
307 
308         printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg);
309         mep->error = 1;
310         return 1;
311 }
312 
313 #define MAC_ESP_PIO_LOOP(operands, reg1) \
314         asm volatile ( \
315              "1:     moveb " operands " \n" \
316              "       subqw #1,%1        \n" \
317              "       jbne 1b            \n" \
318              : "+a" (addr), "+r" (reg1) \
319              : "a" (fifo))
320 
321 #define MAC_ESP_PIO_FILL(operands, reg1) \
322         asm volatile ( \
323              "       moveb " operands " \n" \
324              "       moveb " operands " \n" \
325              "       moveb " operands " \n" \
326              "       moveb " operands " \n" \
327              "       moveb " operands " \n" \
328              "       moveb " operands " \n" \
329              "       moveb " operands " \n" \
330              "       moveb " operands " \n" \
331              "       moveb " operands " \n" \
332              "       moveb " operands " \n" \
333              "       moveb " operands " \n" \
334              "       moveb " operands " \n" \
335              "       moveb " operands " \n" \
336              "       moveb " operands " \n" \
337              "       moveb " operands " \n" \
338              "       moveb " operands " \n" \
339              "       subqw #8,%1        \n" \
340              "       subqw #8,%1        \n" \
341              : "+a" (addr), "+r" (reg1) \
342              : "a" (fifo))
343 
344 #define MAC_ESP_FIFO_SIZE 16
345 
346 static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
347                                  u32 dma_count, int write, u8 cmd)
348 {
349         struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
350         u8 *fifo = esp->regs + ESP_FDATA * 16;
351 
352         cmd &= ~ESP_CMD_DMA;
353         mep->error = 0;
354 
355         if (write) {
356                 scsi_esp_cmd(esp, cmd);
357 
358                 while (1) {
359                         unsigned int n;
360 
361                         n = mac_esp_wait_for_fifo(esp);
362                         if (!n)
363                                 break;
364 
365                         if (n > esp_count)
366                                 n = esp_count;
367                         esp_count -= n;
368 
369                         MAC_ESP_PIO_LOOP("%2@,%0@+", n);
370 
371                         if (!esp_count)
372                                 break;
373 
374                         if (mac_esp_wait_for_intr(esp))
375                                 break;
376 
377                         if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) &&
378                             ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP))
379                                 break;
380 
381                         esp->ireg = esp_read8(ESP_INTRPT);
382                         if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
383                             ESP_INTR_BSERV)
384                                 break;
385 
386                         scsi_esp_cmd(esp, ESP_CMD_TI);
387                 }
388         } else {
389                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
390 
391                 if (esp_count >= MAC_ESP_FIFO_SIZE)
392                         MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
393                 else
394                         MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);
395 
396                 scsi_esp_cmd(esp, cmd);
397 
398                 while (esp_count) {
399                         unsigned int n;
400 
401                         if (mac_esp_wait_for_intr(esp))
402                                 break;
403 
404                         if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) &&
405                             ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP))
406                                 break;
407 
408                         esp->ireg = esp_read8(ESP_INTRPT);
409                         if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
410                             ESP_INTR_BSERV)
411                                 break;
412 
413                         n = MAC_ESP_FIFO_SIZE -
414                             (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
415                         if (n > esp_count)
416                                 n = esp_count;
417 
418                         if (n == MAC_ESP_FIFO_SIZE) {
419                                 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
420                         } else {
421                                 esp_count -= n;
422                                 MAC_ESP_PIO_LOOP("%0@+,%2@", n);
423                         }
424 
425                         scsi_esp_cmd(esp, ESP_CMD_TI);
426                 }
427         }
428 }
429 
430 static int mac_esp_irq_pending(struct esp *esp)
431 {
432         if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
433                 return 1;
434         return 0;
435 }
436 
437 static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
438 {
439         return dma_len > 0xFFFF ? 0xFFFF : dma_len;
440 }
441 
442 static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
443 {
444         int got_intr;
445 
446         /*
447          * This is an edge triggered IRQ, so we have to be careful to
448          * avoid missing a transition when it is shared by two ESP devices.
449          */
450 
451         do {
452                 got_intr = 0;
453                 if (esp_chips[0] &&
454                     (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
455                         (void)scsi_esp_intr(irq, esp_chips[0]);
456                         got_intr = 1;
457                 }
458                 if (esp_chips[1] &&
459                     (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
460                         (void)scsi_esp_intr(irq, esp_chips[1]);
461                         got_intr = 1;
462                 }
463         } while (got_intr);
464 
465         return IRQ_HANDLED;
466 }
467 
468 static struct esp_driver_ops mac_esp_ops = {
469         .esp_write8       = mac_esp_write8,
470         .esp_read8        = mac_esp_read8,
471         .map_single       = mac_esp_map_single,
472         .map_sg           = mac_esp_map_sg,
473         .unmap_single     = mac_esp_unmap_single,
474         .unmap_sg         = mac_esp_unmap_sg,
475         .irq_pending      = mac_esp_irq_pending,
476         .dma_length_limit = mac_esp_dma_length_limit,
477         .reset_dma        = mac_esp_reset_dma,
478         .dma_drain        = mac_esp_dma_drain,
479         .dma_invalidate   = mac_esp_dma_invalidate,
480         .send_dma_cmd     = mac_esp_send_pdma_cmd,
481         .dma_error        = mac_esp_dma_error,
482 };
483 
484 static int esp_mac_probe(struct platform_device *dev)
485 {
486         struct scsi_host_template *tpnt = &scsi_esp_template;
487         struct Scsi_Host *host;
488         struct esp *esp;
489         int err;
490         struct mac_esp_priv *mep;
491 
492         if (!MACH_IS_MAC)
493                 return -ENODEV;
494 
495         if (dev->id > 1)
496                 return -ENODEV;
497 
498         host = scsi_host_alloc(tpnt, sizeof(struct esp));
499 
500         err = -ENOMEM;
501         if (!host)
502                 goto fail;
503 
504         host->max_id = 8;
505         host->use_clustering = DISABLE_CLUSTERING;
506         esp = shost_priv(host);
507 
508         esp->host = host;
509         esp->dev = dev;
510 
511         esp->command_block = kzalloc(16, GFP_KERNEL);
512         if (!esp->command_block)
513                 goto fail_unlink;
514         esp->command_block_dma = (dma_addr_t)esp->command_block;
515 
516         esp->scsi_id = 7;
517         host->this_id = esp->scsi_id;
518         esp->scsi_id_mask = 1 << esp->scsi_id;
519 
520         mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
521         if (!mep)
522                 goto fail_free_command_block;
523         mep->esp = esp;
524         platform_set_drvdata(dev, mep);
525 
526         switch (macintosh_config->scsi_type) {
527         case MAC_SCSI_QUADRA:
528                 esp->cfreq     = 16500000;
529                 esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA;
530                 mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
531                 mep->pdma_regs = NULL;
532                 break;
533         case MAC_SCSI_QUADRA2:
534                 esp->cfreq     = 25000000;
535                 esp->regs      = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
536                                  dev->id * MAC_ESP_REGS_SPACING);
537                 mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
538                 mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
539                                  dev->id * MAC_ESP_PDMA_REG_SPACING);
540                 nubus_writel(0x1d1, mep->pdma_regs);
541                 break;
542         case MAC_SCSI_QUADRA3:
543                 /* These quadras have a real DMA controller (the PSC) but we
544                  * don't know how to drive it so we must use PIO instead.
545                  */
546                 esp->cfreq     = 25000000;
547                 esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA3;
548                 mep->pdma_io   = NULL;
549                 mep->pdma_regs = NULL;
550                 break;
551         }
552 
553         esp->ops = &mac_esp_ops;
554         if (mep->pdma_io == NULL) {
555                 printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
556                 esp_write8(0, ESP_TCLOW);
557                 esp_write8(0, ESP_TCMED);
558                 esp->flags = ESP_FLAG_DISABLE_SYNC;
559                 mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd;
560         } else {
561                 printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
562         }
563 
564         host->irq = IRQ_MAC_SCSI;
565         esp_chips[dev->id] = esp;
566         mb();
567         if (esp_chips[!dev->id] == NULL) {
568                 err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
569                 if (err < 0) {
570                         esp_chips[dev->id] = NULL;
571                         goto fail_free_priv;
572                 }
573         }
574 
575         err = scsi_esp_register(esp, &dev->dev);
576         if (err)
577                 goto fail_free_irq;
578 
579         return 0;
580 
581 fail_free_irq:
582         if (esp_chips[!dev->id] == NULL)
583                 free_irq(host->irq, esp);
584 fail_free_priv:
585         kfree(mep);
586 fail_free_command_block:
587         kfree(esp->command_block);
588 fail_unlink:
589         scsi_host_put(host);
590 fail:
591         return err;
592 }
593 
594 static int esp_mac_remove(struct platform_device *dev)
595 {
596         struct mac_esp_priv *mep = platform_get_drvdata(dev);
597         struct esp *esp = mep->esp;
598         unsigned int irq = esp->host->irq;
599 
600         scsi_esp_unregister(esp);
601 
602         esp_chips[dev->id] = NULL;
603         if (!(esp_chips[0] || esp_chips[1]))
604                 free_irq(irq, NULL);
605 
606         kfree(mep);
607 
608         kfree(esp->command_block);
609 
610         scsi_host_put(esp->host);
611 
612         return 0;
613 }
614 
615 static struct platform_driver esp_mac_driver = {
616         .probe    = esp_mac_probe,
617         .remove   = esp_mac_remove,
618         .driver   = {
619                 .name   = DRV_MODULE_NAME,
620                 .owner  = THIS_MODULE,
621         },
622 };
623 
624 static int __init mac_esp_init(void)
625 {
626         return platform_driver_register(&esp_mac_driver);
627 }
628 
629 static void __exit mac_esp_exit(void)
630 {
631         platform_driver_unregister(&esp_mac_driver);
632 }
633 
634 MODULE_DESCRIPTION("Mac ESP SCSI driver");
635 MODULE_AUTHOR("Finn Thain <fthain@telegraphics.com.au>");
636 MODULE_LICENSE("GPL v2");
637 MODULE_VERSION(DRV_VERSION);
638 MODULE_ALIAS("platform:" DRV_MODULE_NAME);
639 
640 module_init(mac_esp_init);
641 module_exit(mac_esp_exit);
642 

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