Version:  2.0.40 2.2.26 2.4.37 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 3.18 3.19

Linux/drivers/dma/sh/shdmac.c

  1 /*
  2  * Renesas SuperH DMA Engine support
  3  *
  4  * base is drivers/dma/flsdma.c
  5  *
  6  * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
  7  * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
  8  * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
  9  * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
 10  *
 11  * This is free software; you can redistribute it and/or modify
 12  * it under the terms of the GNU General Public License as published by
 13  * the Free Software Foundation; either version 2 of the License, or
 14  * (at your option) any later version.
 15  *
 16  * - DMA of SuperH does not have Hardware DMA chain mode.
 17  * - MAX DMA size is 16MB.
 18  *
 19  */
 20 
 21 #include <linux/delay.h>
 22 #include <linux/dmaengine.h>
 23 #include <linux/err.h>
 24 #include <linux/init.h>
 25 #include <linux/interrupt.h>
 26 #include <linux/kdebug.h>
 27 #include <linux/module.h>
 28 #include <linux/notifier.h>
 29 #include <linux/of.h>
 30 #include <linux/of_device.h>
 31 #include <linux/platform_device.h>
 32 #include <linux/pm_runtime.h>
 33 #include <linux/rculist.h>
 34 #include <linux/sh_dma.h>
 35 #include <linux/slab.h>
 36 #include <linux/spinlock.h>
 37 
 38 #include "../dmaengine.h"
 39 #include "shdma.h"
 40 
 41 /* DMA registers */
 42 #define SAR     0x00    /* Source Address Register */
 43 #define DAR     0x04    /* Destination Address Register */
 44 #define TCR     0x08    /* Transfer Count Register */
 45 #define CHCR    0x0C    /* Channel Control Register */
 46 #define DMAOR   0x40    /* DMA Operation Register */
 47 
 48 #define TEND    0x18 /* USB-DMAC */
 49 
 50 #define SH_DMAE_DRV_NAME "sh-dma-engine"
 51 
 52 /* Default MEMCPY transfer size = 2^2 = 4 bytes */
 53 #define LOG2_DEFAULT_XFER_SIZE  2
 54 #define SH_DMA_SLAVE_NUMBER 256
 55 #define SH_DMA_TCR_MAX (16 * 1024 * 1024 - 1)
 56 
 57 /*
 58  * Used for write-side mutual exclusion for the global device list,
 59  * read-side synchronization by way of RCU, and per-controller data.
 60  */
 61 static DEFINE_SPINLOCK(sh_dmae_lock);
 62 static LIST_HEAD(sh_dmae_devices);
 63 
 64 /*
 65  * Different DMAC implementations provide different ways to clear DMA channels:
 66  * (1) none - no CHCLR registers are available
 67  * (2) one CHCLR register per channel - 0 has to be written to it to clear
 68  *     channel buffers
 69  * (3) one CHCLR per several channels - 1 has to be written to the bit,
 70  *     corresponding to the specific channel to reset it
 71  */
 72 static void channel_clear(struct sh_dmae_chan *sh_dc)
 73 {
 74         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
 75         const struct sh_dmae_channel *chan_pdata = shdev->pdata->channel +
 76                 sh_dc->shdma_chan.id;
 77         u32 val = shdev->pdata->chclr_bitwise ? 1 << chan_pdata->chclr_bit : 0;
 78 
 79         __raw_writel(val, shdev->chan_reg + chan_pdata->chclr_offset);
 80 }
 81 
 82 static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
 83 {
 84         __raw_writel(data, sh_dc->base + reg);
 85 }
 86 
 87 static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
 88 {
 89         return __raw_readl(sh_dc->base + reg);
 90 }
 91 
 92 static u16 dmaor_read(struct sh_dmae_device *shdev)
 93 {
 94         void __iomem *addr = shdev->chan_reg + DMAOR;
 95 
 96         if (shdev->pdata->dmaor_is_32bit)
 97                 return __raw_readl(addr);
 98         else
 99                 return __raw_readw(addr);
100 }
101 
102 static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
103 {
104         void __iomem *addr = shdev->chan_reg + DMAOR;
105 
106         if (shdev->pdata->dmaor_is_32bit)
107                 __raw_writel(data, addr);
108         else
109                 __raw_writew(data, addr);
110 }
111 
112 static void chcr_write(struct sh_dmae_chan *sh_dc, u32 data)
113 {
114         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
115 
116         __raw_writel(data, sh_dc->base + shdev->chcr_offset);
117 }
118 
119 static u32 chcr_read(struct sh_dmae_chan *sh_dc)
120 {
121         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
122 
123         return __raw_readl(sh_dc->base + shdev->chcr_offset);
124 }
125 
126 /*
127  * Reset DMA controller
128  *
129  * SH7780 has two DMAOR register
130  */
131 static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
132 {
133         unsigned short dmaor;
134         unsigned long flags;
135 
136         spin_lock_irqsave(&sh_dmae_lock, flags);
137 
138         dmaor = dmaor_read(shdev);
139         dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
140 
141         spin_unlock_irqrestore(&sh_dmae_lock, flags);
142 }
143 
144 static int sh_dmae_rst(struct sh_dmae_device *shdev)
145 {
146         unsigned short dmaor;
147         unsigned long flags;
148 
149         spin_lock_irqsave(&sh_dmae_lock, flags);
150 
151         dmaor = dmaor_read(shdev) & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME);
152 
153         if (shdev->pdata->chclr_present) {
154                 int i;
155                 for (i = 0; i < shdev->pdata->channel_num; i++) {
156                         struct sh_dmae_chan *sh_chan = shdev->chan[i];
157                         if (sh_chan)
158                                 channel_clear(sh_chan);
159                 }
160         }
161 
162         dmaor_write(shdev, dmaor | shdev->pdata->dmaor_init);
163 
164         dmaor = dmaor_read(shdev);
165 
166         spin_unlock_irqrestore(&sh_dmae_lock, flags);
167 
168         if (dmaor & (DMAOR_AE | DMAOR_NMIF)) {
169                 dev_warn(shdev->shdma_dev.dma_dev.dev, "Can't initialize DMAOR.\n");
170                 return -EIO;
171         }
172         if (shdev->pdata->dmaor_init & ~dmaor)
173                 dev_warn(shdev->shdma_dev.dma_dev.dev,
174                          "DMAOR=0x%x hasn't latched the initial value 0x%x.\n",
175                          dmaor, shdev->pdata->dmaor_init);
176         return 0;
177 }
178 
179 static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
180 {
181         u32 chcr = chcr_read(sh_chan);
182 
183         if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
184                 return true; /* working */
185 
186         return false; /* waiting */
187 }
188 
189 static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
190 {
191         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
192         const struct sh_dmae_pdata *pdata = shdev->pdata;
193         int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
194                 ((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
195 
196         if (cnt >= pdata->ts_shift_num)
197                 cnt = 0;
198 
199         return pdata->ts_shift[cnt];
200 }
201 
202 static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
203 {
204         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
205         const struct sh_dmae_pdata *pdata = shdev->pdata;
206         int i;
207 
208         for (i = 0; i < pdata->ts_shift_num; i++)
209                 if (pdata->ts_shift[i] == l2size)
210                         break;
211 
212         if (i == pdata->ts_shift_num)
213                 i = 0;
214 
215         return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
216                 ((i << pdata->ts_high_shift) & pdata->ts_high_mask);
217 }
218 
219 static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
220 {
221         sh_dmae_writel(sh_chan, hw->sar, SAR);
222         sh_dmae_writel(sh_chan, hw->dar, DAR);
223         sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
224 }
225 
226 static void dmae_start(struct sh_dmae_chan *sh_chan)
227 {
228         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
229         u32 chcr = chcr_read(sh_chan);
230 
231         if (shdev->pdata->needs_tend_set)
232                 sh_dmae_writel(sh_chan, 0xFFFFFFFF, TEND);
233 
234         chcr |= CHCR_DE | shdev->chcr_ie_bit;
235         chcr_write(sh_chan, chcr & ~CHCR_TE);
236 }
237 
238 static void dmae_init(struct sh_dmae_chan *sh_chan)
239 {
240         /*
241          * Default configuration for dual address memory-memory transfer.
242          */
243         u32 chcr = DM_INC | SM_INC | RS_AUTO | log2size_to_chcr(sh_chan,
244                                                    LOG2_DEFAULT_XFER_SIZE);
245         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
246         chcr_write(sh_chan, chcr);
247 }
248 
249 static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
250 {
251         /* If DMA is active, cannot set CHCR. TODO: remove this superfluous check */
252         if (dmae_is_busy(sh_chan))
253                 return -EBUSY;
254 
255         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
256         chcr_write(sh_chan, val);
257 
258         return 0;
259 }
260 
261 static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
262 {
263         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
264         const struct sh_dmae_pdata *pdata = shdev->pdata;
265         const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->shdma_chan.id];
266         void __iomem *addr = shdev->dmars;
267         unsigned int shift = chan_pdata->dmars_bit;
268 
269         if (dmae_is_busy(sh_chan))
270                 return -EBUSY;
271 
272         if (pdata->no_dmars)
273                 return 0;
274 
275         /* in the case of a missing DMARS resource use first memory window */
276         if (!addr)
277                 addr = shdev->chan_reg;
278         addr += chan_pdata->dmars;
279 
280         __raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
281                      addr);
282 
283         return 0;
284 }
285 
286 static void sh_dmae_start_xfer(struct shdma_chan *schan,
287                                struct shdma_desc *sdesc)
288 {
289         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
290                                                     shdma_chan);
291         struct sh_dmae_desc *sh_desc = container_of(sdesc,
292                                         struct sh_dmae_desc, shdma_desc);
293         dev_dbg(sh_chan->shdma_chan.dev, "Queue #%d to %d: %u@%x -> %x\n",
294                 sdesc->async_tx.cookie, sh_chan->shdma_chan.id,
295                 sh_desc->hw.tcr, sh_desc->hw.sar, sh_desc->hw.dar);
296         /* Get the ld start address from ld_queue */
297         dmae_set_reg(sh_chan, &sh_desc->hw);
298         dmae_start(sh_chan);
299 }
300 
301 static bool sh_dmae_channel_busy(struct shdma_chan *schan)
302 {
303         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
304                                                     shdma_chan);
305         return dmae_is_busy(sh_chan);
306 }
307 
308 static void sh_dmae_setup_xfer(struct shdma_chan *schan,
309                                int slave_id)
310 {
311         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
312                                                     shdma_chan);
313 
314         if (slave_id >= 0) {
315                 const struct sh_dmae_slave_config *cfg =
316                         sh_chan->config;
317 
318                 dmae_set_dmars(sh_chan, cfg->mid_rid);
319                 dmae_set_chcr(sh_chan, cfg->chcr);
320         } else {
321                 dmae_init(sh_chan);
322         }
323 }
324 
325 /*
326  * Find a slave channel configuration from the contoller list by either a slave
327  * ID in the non-DT case, or by a MID/RID value in the DT case
328  */
329 static const struct sh_dmae_slave_config *dmae_find_slave(
330         struct sh_dmae_chan *sh_chan, int match)
331 {
332         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
333         const struct sh_dmae_pdata *pdata = shdev->pdata;
334         const struct sh_dmae_slave_config *cfg;
335         int i;
336 
337         if (!sh_chan->shdma_chan.dev->of_node) {
338                 if (match >= SH_DMA_SLAVE_NUMBER)
339                         return NULL;
340 
341                 for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
342                         if (cfg->slave_id == match)
343                                 return cfg;
344         } else {
345                 for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
346                         if (cfg->mid_rid == match) {
347                                 sh_chan->shdma_chan.slave_id = i;
348                                 return cfg;
349                         }
350         }
351 
352         return NULL;
353 }
354 
355 static int sh_dmae_set_slave(struct shdma_chan *schan,
356                              int slave_id, dma_addr_t slave_addr, bool try)
357 {
358         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
359                                                     shdma_chan);
360         const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, slave_id);
361         if (!cfg)
362                 return -ENXIO;
363 
364         if (!try) {
365                 sh_chan->config = cfg;
366                 sh_chan->slave_addr = slave_addr ? : cfg->addr;
367         }
368 
369         return 0;
370 }
371 
372 static void dmae_halt(struct sh_dmae_chan *sh_chan)
373 {
374         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
375         u32 chcr = chcr_read(sh_chan);
376 
377         chcr &= ~(CHCR_DE | CHCR_TE | shdev->chcr_ie_bit);
378         chcr_write(sh_chan, chcr);
379 }
380 
381 static int sh_dmae_desc_setup(struct shdma_chan *schan,
382                               struct shdma_desc *sdesc,
383                               dma_addr_t src, dma_addr_t dst, size_t *len)
384 {
385         struct sh_dmae_desc *sh_desc = container_of(sdesc,
386                                         struct sh_dmae_desc, shdma_desc);
387 
388         if (*len > schan->max_xfer_len)
389                 *len = schan->max_xfer_len;
390 
391         sh_desc->hw.sar = src;
392         sh_desc->hw.dar = dst;
393         sh_desc->hw.tcr = *len;
394 
395         return 0;
396 }
397 
398 static void sh_dmae_halt(struct shdma_chan *schan)
399 {
400         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
401                                                     shdma_chan);
402         dmae_halt(sh_chan);
403 }
404 
405 static bool sh_dmae_chan_irq(struct shdma_chan *schan, int irq)
406 {
407         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
408                                                     shdma_chan);
409 
410         if (!(chcr_read(sh_chan) & CHCR_TE))
411                 return false;
412 
413         /* DMA stop */
414         dmae_halt(sh_chan);
415 
416         return true;
417 }
418 
419 static size_t sh_dmae_get_partial(struct shdma_chan *schan,
420                                   struct shdma_desc *sdesc)
421 {
422         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
423                                                     shdma_chan);
424         struct sh_dmae_desc *sh_desc = container_of(sdesc,
425                                         struct sh_dmae_desc, shdma_desc);
426         return sh_desc->hw.tcr -
427                 (sh_dmae_readl(sh_chan, TCR) << sh_chan->xmit_shift);
428 }
429 
430 /* Called from error IRQ or NMI */
431 static bool sh_dmae_reset(struct sh_dmae_device *shdev)
432 {
433         bool ret;
434 
435         /* halt the dma controller */
436         sh_dmae_ctl_stop(shdev);
437 
438         /* We cannot detect, which channel caused the error, have to reset all */
439         ret = shdma_reset(&shdev->shdma_dev);
440 
441         sh_dmae_rst(shdev);
442 
443         return ret;
444 }
445 
446 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARM)
447 static irqreturn_t sh_dmae_err(int irq, void *data)
448 {
449         struct sh_dmae_device *shdev = data;
450 
451         if (!(dmaor_read(shdev) & DMAOR_AE))
452                 return IRQ_NONE;
453 
454         sh_dmae_reset(shdev);
455         return IRQ_HANDLED;
456 }
457 #endif
458 
459 static bool sh_dmae_desc_completed(struct shdma_chan *schan,
460                                    struct shdma_desc *sdesc)
461 {
462         struct sh_dmae_chan *sh_chan = container_of(schan,
463                                         struct sh_dmae_chan, shdma_chan);
464         struct sh_dmae_desc *sh_desc = container_of(sdesc,
465                                         struct sh_dmae_desc, shdma_desc);
466         u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
467         u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
468 
469         return  (sdesc->direction == DMA_DEV_TO_MEM &&
470                  (sh_desc->hw.dar + sh_desc->hw.tcr) == dar_buf) ||
471                 (sdesc->direction != DMA_DEV_TO_MEM &&
472                  (sh_desc->hw.sar + sh_desc->hw.tcr) == sar_buf);
473 }
474 
475 static bool sh_dmae_nmi_notify(struct sh_dmae_device *shdev)
476 {
477         /* Fast path out if NMIF is not asserted for this controller */
478         if ((dmaor_read(shdev) & DMAOR_NMIF) == 0)
479                 return false;
480 
481         return sh_dmae_reset(shdev);
482 }
483 
484 static int sh_dmae_nmi_handler(struct notifier_block *self,
485                                unsigned long cmd, void *data)
486 {
487         struct sh_dmae_device *shdev;
488         int ret = NOTIFY_DONE;
489         bool triggered;
490 
491         /*
492          * Only concern ourselves with NMI events.
493          *
494          * Normally we would check the die chain value, but as this needs
495          * to be architecture independent, check for NMI context instead.
496          */
497         if (!in_nmi())
498                 return NOTIFY_DONE;
499 
500         rcu_read_lock();
501         list_for_each_entry_rcu(shdev, &sh_dmae_devices, node) {
502                 /*
503                  * Only stop if one of the controllers has NMIF asserted,
504                  * we do not want to interfere with regular address error
505                  * handling or NMI events that don't concern the DMACs.
506                  */
507                 triggered = sh_dmae_nmi_notify(shdev);
508                 if (triggered == true)
509                         ret = NOTIFY_OK;
510         }
511         rcu_read_unlock();
512 
513         return ret;
514 }
515 
516 static struct notifier_block sh_dmae_nmi_notifier __read_mostly = {
517         .notifier_call  = sh_dmae_nmi_handler,
518 
519         /* Run before NMI debug handler and KGDB */
520         .priority       = 1,
521 };
522 
523 static int sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
524                                         int irq, unsigned long flags)
525 {
526         const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
527         struct shdma_dev *sdev = &shdev->shdma_dev;
528         struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev);
529         struct sh_dmae_chan *sh_chan;
530         struct shdma_chan *schan;
531         int err;
532 
533         sh_chan = devm_kzalloc(sdev->dma_dev.dev, sizeof(struct sh_dmae_chan),
534                                GFP_KERNEL);
535         if (!sh_chan) {
536                 dev_err(sdev->dma_dev.dev,
537                         "No free memory for allocating dma channels!\n");
538                 return -ENOMEM;
539         }
540 
541         schan = &sh_chan->shdma_chan;
542         schan->max_xfer_len = SH_DMA_TCR_MAX + 1;
543 
544         shdma_chan_probe(sdev, schan, id);
545 
546         sh_chan->base = shdev->chan_reg + chan_pdata->offset;
547 
548         /* set up channel irq */
549         if (pdev->id >= 0)
550                 snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
551                          "sh-dmae%d.%d", pdev->id, id);
552         else
553                 snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
554                          "sh-dma%d", id);
555 
556         err = shdma_request_irq(schan, irq, flags, sh_chan->dev_id);
557         if (err) {
558                 dev_err(sdev->dma_dev.dev,
559                         "DMA channel %d request_irq error %d\n",
560                         id, err);
561                 goto err_no_irq;
562         }
563 
564         shdev->chan[id] = sh_chan;
565         return 0;
566 
567 err_no_irq:
568         /* remove from dmaengine device node */
569         shdma_chan_remove(schan);
570         return err;
571 }
572 
573 static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
574 {
575         struct shdma_chan *schan;
576         int i;
577 
578         shdma_for_each_chan(schan, &shdev->shdma_dev, i) {
579                 BUG_ON(!schan);
580 
581                 shdma_chan_remove(schan);
582         }
583 }
584 
585 static void sh_dmae_shutdown(struct platform_device *pdev)
586 {
587         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
588         sh_dmae_ctl_stop(shdev);
589 }
590 
591 static int sh_dmae_runtime_suspend(struct device *dev)
592 {
593         return 0;
594 }
595 
596 static int sh_dmae_runtime_resume(struct device *dev)
597 {
598         struct sh_dmae_device *shdev = dev_get_drvdata(dev);
599 
600         return sh_dmae_rst(shdev);
601 }
602 
603 #ifdef CONFIG_PM
604 static int sh_dmae_suspend(struct device *dev)
605 {
606         return 0;
607 }
608 
609 static int sh_dmae_resume(struct device *dev)
610 {
611         struct sh_dmae_device *shdev = dev_get_drvdata(dev);
612         int i, ret;
613 
614         ret = sh_dmae_rst(shdev);
615         if (ret < 0)
616                 dev_err(dev, "Failed to reset!\n");
617 
618         for (i = 0; i < shdev->pdata->channel_num; i++) {
619                 struct sh_dmae_chan *sh_chan = shdev->chan[i];
620 
621                 if (!sh_chan->shdma_chan.desc_num)
622                         continue;
623 
624                 if (sh_chan->shdma_chan.slave_id >= 0) {
625                         const struct sh_dmae_slave_config *cfg = sh_chan->config;
626                         dmae_set_dmars(sh_chan, cfg->mid_rid);
627                         dmae_set_chcr(sh_chan, cfg->chcr);
628                 } else {
629                         dmae_init(sh_chan);
630                 }
631         }
632 
633         return 0;
634 }
635 #else
636 #define sh_dmae_suspend NULL
637 #define sh_dmae_resume NULL
638 #endif
639 
640 static const struct dev_pm_ops sh_dmae_pm = {
641         .suspend                = sh_dmae_suspend,
642         .resume                 = sh_dmae_resume,
643         .runtime_suspend        = sh_dmae_runtime_suspend,
644         .runtime_resume         = sh_dmae_runtime_resume,
645 };
646 
647 static dma_addr_t sh_dmae_slave_addr(struct shdma_chan *schan)
648 {
649         struct sh_dmae_chan *sh_chan = container_of(schan,
650                                         struct sh_dmae_chan, shdma_chan);
651 
652         /*
653          * Implicit BUG_ON(!sh_chan->config)
654          * This is an exclusive slave DMA operation, may only be called after a
655          * successful slave configuration.
656          */
657         return sh_chan->slave_addr;
658 }
659 
660 static struct shdma_desc *sh_dmae_embedded_desc(void *buf, int i)
661 {
662         return &((struct sh_dmae_desc *)buf)[i].shdma_desc;
663 }
664 
665 static const struct shdma_ops sh_dmae_shdma_ops = {
666         .desc_completed = sh_dmae_desc_completed,
667         .halt_channel = sh_dmae_halt,
668         .channel_busy = sh_dmae_channel_busy,
669         .slave_addr = sh_dmae_slave_addr,
670         .desc_setup = sh_dmae_desc_setup,
671         .set_slave = sh_dmae_set_slave,
672         .setup_xfer = sh_dmae_setup_xfer,
673         .start_xfer = sh_dmae_start_xfer,
674         .embedded_desc = sh_dmae_embedded_desc,
675         .chan_irq = sh_dmae_chan_irq,
676         .get_partial = sh_dmae_get_partial,
677 };
678 
679 static const struct of_device_id sh_dmae_of_match[] = {
680         {.compatible = "renesas,shdma-r8a73a4", .data = r8a73a4_shdma_devid,},
681         {}
682 };
683 MODULE_DEVICE_TABLE(of, sh_dmae_of_match);
684 
685 static int sh_dmae_probe(struct platform_device *pdev)
686 {
687         const struct sh_dmae_pdata *pdata;
688         unsigned long chan_flag[SH_DMAE_MAX_CHANNELS] = {};
689         int chan_irq[SH_DMAE_MAX_CHANNELS];
690 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARM)
691         unsigned long irqflags = 0;
692         int errirq;
693 #endif
694         int err, i, irq_cnt = 0, irqres = 0, irq_cap = 0;
695         struct sh_dmae_device *shdev;
696         struct dma_device *dma_dev;
697         struct resource *chan, *dmars, *errirq_res, *chanirq_res;
698 
699         if (pdev->dev.of_node)
700                 pdata = of_match_device(sh_dmae_of_match, &pdev->dev)->data;
701         else
702                 pdata = dev_get_platdata(&pdev->dev);
703 
704         /* get platform data */
705         if (!pdata || !pdata->channel_num)
706                 return -ENODEV;
707 
708         chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
709         /* DMARS area is optional */
710         dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
711         /*
712          * IRQ resources:
713          * 1. there always must be at least one IRQ IO-resource. On SH4 it is
714          *    the error IRQ, in which case it is the only IRQ in this resource:
715          *    start == end. If it is the only IRQ resource, all channels also
716          *    use the same IRQ.
717          * 2. DMA channel IRQ resources can be specified one per resource or in
718          *    ranges (start != end)
719          * 3. iff all events (channels and, optionally, error) on this
720          *    controller use the same IRQ, only one IRQ resource can be
721          *    specified, otherwise there must be one IRQ per channel, even if
722          *    some of them are equal
723          * 4. if all IRQs on this controller are equal or if some specific IRQs
724          *    specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
725          *    requested with the IRQF_SHARED flag
726          */
727         errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
728         if (!chan || !errirq_res)
729                 return -ENODEV;
730 
731         shdev = devm_kzalloc(&pdev->dev, sizeof(struct sh_dmae_device),
732                              GFP_KERNEL);
733         if (!shdev) {
734                 dev_err(&pdev->dev, "Not enough memory\n");
735                 return -ENOMEM;
736         }
737 
738         dma_dev = &shdev->shdma_dev.dma_dev;
739 
740         shdev->chan_reg = devm_ioremap_resource(&pdev->dev, chan);
741         if (IS_ERR(shdev->chan_reg))
742                 return PTR_ERR(shdev->chan_reg);
743         if (dmars) {
744                 shdev->dmars = devm_ioremap_resource(&pdev->dev, dmars);
745                 if (IS_ERR(shdev->dmars))
746                         return PTR_ERR(shdev->dmars);
747         }
748 
749         if (!pdata->slave_only)
750                 dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
751         if (pdata->slave && pdata->slave_num)
752                 dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
753 
754         /* Default transfer size of 32 bytes requires 32-byte alignment */
755         dma_dev->copy_align = LOG2_DEFAULT_XFER_SIZE;
756 
757         shdev->shdma_dev.ops = &sh_dmae_shdma_ops;
758         shdev->shdma_dev.desc_size = sizeof(struct sh_dmae_desc);
759         err = shdma_init(&pdev->dev, &shdev->shdma_dev,
760                               pdata->channel_num);
761         if (err < 0)
762                 goto eshdma;
763 
764         /* platform data */
765         shdev->pdata = pdata;
766 
767         if (pdata->chcr_offset)
768                 shdev->chcr_offset = pdata->chcr_offset;
769         else
770                 shdev->chcr_offset = CHCR;
771 
772         if (pdata->chcr_ie_bit)
773                 shdev->chcr_ie_bit = pdata->chcr_ie_bit;
774         else
775                 shdev->chcr_ie_bit = CHCR_IE;
776 
777         platform_set_drvdata(pdev, shdev);
778 
779         pm_runtime_enable(&pdev->dev);
780         err = pm_runtime_get_sync(&pdev->dev);
781         if (err < 0)
782                 dev_err(&pdev->dev, "%s(): GET = %d\n", __func__, err);
783 
784         spin_lock_irq(&sh_dmae_lock);
785         list_add_tail_rcu(&shdev->node, &sh_dmae_devices);
786         spin_unlock_irq(&sh_dmae_lock);
787 
788         /* reset dma controller - only needed as a test */
789         err = sh_dmae_rst(shdev);
790         if (err)
791                 goto rst_err;
792 
793 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
794         chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
795 
796         if (!chanirq_res)
797                 chanirq_res = errirq_res;
798         else
799                 irqres++;
800 
801         if (chanirq_res == errirq_res ||
802             (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
803                 irqflags = IRQF_SHARED;
804 
805         errirq = errirq_res->start;
806 
807         err = devm_request_irq(&pdev->dev, errirq, sh_dmae_err, irqflags,
808                                "DMAC Address Error", shdev);
809         if (err) {
810                 dev_err(&pdev->dev,
811                         "DMA failed requesting irq #%d, error %d\n",
812                         errirq, err);
813                 goto eirq_err;
814         }
815 
816 #else
817         chanirq_res = errirq_res;
818 #endif /* CONFIG_CPU_SH4 || CONFIG_ARCH_SHMOBILE */
819 
820         if (chanirq_res->start == chanirq_res->end &&
821             !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
822                 /* Special case - all multiplexed */
823                 for (; irq_cnt < pdata->channel_num; irq_cnt++) {
824                         if (irq_cnt < SH_DMAE_MAX_CHANNELS) {
825                                 chan_irq[irq_cnt] = chanirq_res->start;
826                                 chan_flag[irq_cnt] = IRQF_SHARED;
827                         } else {
828                                 irq_cap = 1;
829                                 break;
830                         }
831                 }
832         } else {
833                 do {
834                         for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
835                                 if (irq_cnt >= SH_DMAE_MAX_CHANNELS) {
836                                         irq_cap = 1;
837                                         break;
838                                 }
839 
840                                 if ((errirq_res->flags & IORESOURCE_BITS) ==
841                                     IORESOURCE_IRQ_SHAREABLE)
842                                         chan_flag[irq_cnt] = IRQF_SHARED;
843                                 else
844                                         chan_flag[irq_cnt] = 0;
845                                 dev_dbg(&pdev->dev,
846                                         "Found IRQ %d for channel %d\n",
847                                         i, irq_cnt);
848                                 chan_irq[irq_cnt++] = i;
849                         }
850 
851                         if (irq_cnt >= SH_DMAE_MAX_CHANNELS)
852                                 break;
853 
854                         chanirq_res = platform_get_resource(pdev,
855                                                 IORESOURCE_IRQ, ++irqres);
856                 } while (irq_cnt < pdata->channel_num && chanirq_res);
857         }
858 
859         /* Create DMA Channel */
860         for (i = 0; i < irq_cnt; i++) {
861                 err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
862                 if (err)
863                         goto chan_probe_err;
864         }
865 
866         if (irq_cap)
867                 dev_notice(&pdev->dev, "Attempting to register %d DMA "
868                            "channels when a maximum of %d are supported.\n",
869                            pdata->channel_num, SH_DMAE_MAX_CHANNELS);
870 
871         pm_runtime_put(&pdev->dev);
872 
873         err = dma_async_device_register(&shdev->shdma_dev.dma_dev);
874         if (err < 0)
875                 goto edmadevreg;
876 
877         return err;
878 
879 edmadevreg:
880         pm_runtime_get(&pdev->dev);
881 
882 chan_probe_err:
883         sh_dmae_chan_remove(shdev);
884 
885 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
886 eirq_err:
887 #endif
888 rst_err:
889         spin_lock_irq(&sh_dmae_lock);
890         list_del_rcu(&shdev->node);
891         spin_unlock_irq(&sh_dmae_lock);
892 
893         pm_runtime_put(&pdev->dev);
894         pm_runtime_disable(&pdev->dev);
895 
896         shdma_cleanup(&shdev->shdma_dev);
897 eshdma:
898         synchronize_rcu();
899 
900         return err;
901 }
902 
903 static int sh_dmae_remove(struct platform_device *pdev)
904 {
905         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
906         struct dma_device *dma_dev = &shdev->shdma_dev.dma_dev;
907 
908         dma_async_device_unregister(dma_dev);
909 
910         spin_lock_irq(&sh_dmae_lock);
911         list_del_rcu(&shdev->node);
912         spin_unlock_irq(&sh_dmae_lock);
913 
914         pm_runtime_disable(&pdev->dev);
915 
916         sh_dmae_chan_remove(shdev);
917         shdma_cleanup(&shdev->shdma_dev);
918 
919         synchronize_rcu();
920 
921         return 0;
922 }
923 
924 static struct platform_driver sh_dmae_driver = {
925         .driver         = {
926                 .pm     = &sh_dmae_pm,
927                 .name   = SH_DMAE_DRV_NAME,
928                 .of_match_table = sh_dmae_of_match,
929         },
930         .remove         = sh_dmae_remove,
931         .shutdown       = sh_dmae_shutdown,
932 };
933 
934 static int __init sh_dmae_init(void)
935 {
936         /* Wire up NMI handling */
937         int err = register_die_notifier(&sh_dmae_nmi_notifier);
938         if (err)
939                 return err;
940 
941         return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
942 }
943 module_init(sh_dmae_init);
944 
945 static void __exit sh_dmae_exit(void)
946 {
947         platform_driver_unregister(&sh_dmae_driver);
948 
949         unregister_die_notifier(&sh_dmae_nmi_notifier);
950 }
951 module_exit(sh_dmae_exit);
952 
953 MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
954 MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
955 MODULE_LICENSE("GPL");
956 MODULE_ALIAS("platform:" SH_DMAE_DRV_NAME);
957 

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