dmaengine: shdma: extend .device_terminate_all() to record partial transfer
[linux-2.6.git] / drivers / dma / shdma.c
1 /*
2  * Renesas SuperH DMA Engine support
3  *
4  * base is drivers/dma/flsdma.c
5  *
6  * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
7  * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
8  * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
9  *
10  * This is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * - DMA of SuperH does not have Hardware DMA chain mode.
16  * - MAX DMA size is 16MB.
17  *
18  */
19
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/interrupt.h>
23 #include <linux/dmaengine.h>
24 #include <linux/delay.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/platform_device.h>
27 #include <linux/pm_runtime.h>
28
29 #include <asm/dmaengine.h>
30
31 #include "shdma.h"
32
33 /* DMA descriptor control */
34 enum sh_dmae_desc_status {
35         DESC_IDLE,
36         DESC_PREPARED,
37         DESC_SUBMITTED,
38         DESC_COMPLETED, /* completed, have to call callback */
39         DESC_WAITING,   /* callback called, waiting for ack / re-submit */
40 };
41
42 #define NR_DESCS_PER_CHANNEL 32
43 /* Default MEMCPY transfer size = 2^2 = 4 bytes */
44 #define LOG2_DEFAULT_XFER_SIZE  2
45
46 /* A bitmask with bits enough for enum sh_dmae_slave_chan_id */
47 static unsigned long sh_dmae_slave_used[BITS_TO_LONGS(SHDMA_SLAVE_NUMBER)];
48
49 static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all);
50
51 static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
52 {
53         __raw_writel(data, sh_dc->base + reg / sizeof(u32));
54 }
55
56 static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
57 {
58         return __raw_readl(sh_dc->base + reg / sizeof(u32));
59 }
60
61 static u16 dmaor_read(struct sh_dmae_device *shdev)
62 {
63         return __raw_readw(shdev->chan_reg + DMAOR / sizeof(u32));
64 }
65
66 static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
67 {
68         __raw_writew(data, shdev->chan_reg + DMAOR / sizeof(u32));
69 }
70
71 /*
72  * Reset DMA controller
73  *
74  * SH7780 has two DMAOR register
75  */
76 static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
77 {
78         unsigned short dmaor = dmaor_read(shdev);
79
80         dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
81 }
82
83 static int sh_dmae_rst(struct sh_dmae_device *shdev)
84 {
85         unsigned short dmaor;
86
87         sh_dmae_ctl_stop(shdev);
88         dmaor = dmaor_read(shdev) | shdev->pdata->dmaor_init;
89
90         dmaor_write(shdev, dmaor);
91         if (dmaor_read(shdev) & (DMAOR_AE | DMAOR_NMIF)) {
92                 pr_warning("dma-sh: Can't initialize DMAOR.\n");
93                 return -EINVAL;
94         }
95         return 0;
96 }
97
98 static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
99 {
100         u32 chcr = sh_dmae_readl(sh_chan, CHCR);
101
102         if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
103                 return true; /* working */
104
105         return false; /* waiting */
106 }
107
108 static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
109 {
110         struct sh_dmae_device *shdev = container_of(sh_chan->common.device,
111                                                 struct sh_dmae_device, common);
112         struct sh_dmae_pdata *pdata = shdev->pdata;
113         int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
114                 ((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
115
116         if (cnt >= pdata->ts_shift_num)
117                 cnt = 0;
118
119         return pdata->ts_shift[cnt];
120 }
121
122 static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
123 {
124         struct sh_dmae_device *shdev = container_of(sh_chan->common.device,
125                                                 struct sh_dmae_device, common);
126         struct sh_dmae_pdata *pdata = shdev->pdata;
127         int i;
128
129         for (i = 0; i < pdata->ts_shift_num; i++)
130                 if (pdata->ts_shift[i] == l2size)
131                         break;
132
133         if (i == pdata->ts_shift_num)
134                 i = 0;
135
136         return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
137                 ((i << pdata->ts_high_shift) & pdata->ts_high_mask);
138 }
139
140 static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
141 {
142         sh_dmae_writel(sh_chan, hw->sar, SAR);
143         sh_dmae_writel(sh_chan, hw->dar, DAR);
144         sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
145 }
146
147 static void dmae_start(struct sh_dmae_chan *sh_chan)
148 {
149         u32 chcr = sh_dmae_readl(sh_chan, CHCR);
150
151         chcr |= CHCR_DE | CHCR_IE;
152         sh_dmae_writel(sh_chan, chcr & ~CHCR_TE, CHCR);
153 }
154
155 static void dmae_halt(struct sh_dmae_chan *sh_chan)
156 {
157         u32 chcr = sh_dmae_readl(sh_chan, CHCR);
158
159         chcr &= ~(CHCR_DE | CHCR_TE | CHCR_IE);
160         sh_dmae_writel(sh_chan, chcr, CHCR);
161 }
162
163 static void dmae_init(struct sh_dmae_chan *sh_chan)
164 {
165         /*
166          * Default configuration for dual address memory-memory transfer.
167          * 0x400 represents auto-request.
168          */
169         u32 chcr = DM_INC | SM_INC | 0x400 | log2size_to_chcr(sh_chan,
170                                                    LOG2_DEFAULT_XFER_SIZE);
171         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
172         sh_dmae_writel(sh_chan, chcr, CHCR);
173 }
174
175 static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
176 {
177         /* When DMA was working, can not set data to CHCR */
178         if (dmae_is_busy(sh_chan))
179                 return -EBUSY;
180
181         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
182         sh_dmae_writel(sh_chan, val, CHCR);
183
184         return 0;
185 }
186
187 static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
188 {
189         struct sh_dmae_device *shdev = container_of(sh_chan->common.device,
190                                                 struct sh_dmae_device, common);
191         struct sh_dmae_pdata *pdata = shdev->pdata;
192         struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->id];
193         u16 __iomem *addr = shdev->dmars + chan_pdata->dmars / sizeof(u16);
194         int shift = chan_pdata->dmars_bit;
195
196         if (dmae_is_busy(sh_chan))
197                 return -EBUSY;
198
199         __raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
200                      addr);
201
202         return 0;
203 }
204
205 static dma_cookie_t sh_dmae_tx_submit(struct dma_async_tx_descriptor *tx)
206 {
207         struct sh_desc *desc = tx_to_sh_desc(tx), *chunk, *last = desc, *c;
208         struct sh_dmae_chan *sh_chan = to_sh_chan(tx->chan);
209         dma_async_tx_callback callback = tx->callback;
210         dma_cookie_t cookie;
211
212         spin_lock_bh(&sh_chan->desc_lock);
213
214         cookie = sh_chan->common.cookie;
215         cookie++;
216         if (cookie < 0)
217                 cookie = 1;
218
219         sh_chan->common.cookie = cookie;
220         tx->cookie = cookie;
221
222         /* Mark all chunks of this descriptor as submitted, move to the queue */
223         list_for_each_entry_safe(chunk, c, desc->node.prev, node) {
224                 /*
225                  * All chunks are on the global ld_free, so, we have to find
226                  * the end of the chain ourselves
227                  */
228                 if (chunk != desc && (chunk->mark == DESC_IDLE ||
229                                       chunk->async_tx.cookie > 0 ||
230                                       chunk->async_tx.cookie == -EBUSY ||
231                                       &chunk->node == &sh_chan->ld_free))
232                         break;
233                 chunk->mark = DESC_SUBMITTED;
234                 /* Callback goes to the last chunk */
235                 chunk->async_tx.callback = NULL;
236                 chunk->cookie = cookie;
237                 list_move_tail(&chunk->node, &sh_chan->ld_queue);
238                 last = chunk;
239         }
240
241         last->async_tx.callback = callback;
242         last->async_tx.callback_param = tx->callback_param;
243
244         dev_dbg(sh_chan->dev, "submit #%d@%p on %d: %x[%d] -> %x\n",
245                 tx->cookie, &last->async_tx, sh_chan->id,
246                 desc->hw.sar, desc->hw.tcr, desc->hw.dar);
247
248         spin_unlock_bh(&sh_chan->desc_lock);
249
250         return cookie;
251 }
252
253 /* Called with desc_lock held */
254 static struct sh_desc *sh_dmae_get_desc(struct sh_dmae_chan *sh_chan)
255 {
256         struct sh_desc *desc;
257
258         list_for_each_entry(desc, &sh_chan->ld_free, node)
259                 if (desc->mark != DESC_PREPARED) {
260                         BUG_ON(desc->mark != DESC_IDLE);
261                         list_del(&desc->node);
262                         return desc;
263                 }
264
265         return NULL;
266 }
267
268 static struct sh_dmae_slave_config *sh_dmae_find_slave(
269         struct sh_dmae_chan *sh_chan, enum sh_dmae_slave_chan_id slave_id)
270 {
271         struct dma_device *dma_dev = sh_chan->common.device;
272         struct sh_dmae_device *shdev = container_of(dma_dev,
273                                         struct sh_dmae_device, common);
274         struct sh_dmae_pdata *pdata = shdev->pdata;
275         int i;
276
277         if ((unsigned)slave_id >= SHDMA_SLAVE_NUMBER)
278                 return NULL;
279
280         for (i = 0; i < pdata->slave_num; i++)
281                 if (pdata->slave[i].slave_id == slave_id)
282                         return pdata->slave + i;
283
284         return NULL;
285 }
286
287 static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
288 {
289         struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
290         struct sh_desc *desc;
291         struct sh_dmae_slave *param = chan->private;
292
293         pm_runtime_get_sync(sh_chan->dev);
294
295         /*
296          * This relies on the guarantee from dmaengine that alloc_chan_resources
297          * never runs concurrently with itself or free_chan_resources.
298          */
299         if (param) {
300                 struct sh_dmae_slave_config *cfg;
301
302                 cfg = sh_dmae_find_slave(sh_chan, param->slave_id);
303                 if (!cfg)
304                         return -EINVAL;
305
306                 if (test_and_set_bit(param->slave_id, sh_dmae_slave_used))
307                         return -EBUSY;
308
309                 param->config = cfg;
310
311                 dmae_set_dmars(sh_chan, cfg->mid_rid);
312                 dmae_set_chcr(sh_chan, cfg->chcr);
313         } else if ((sh_dmae_readl(sh_chan, CHCR) & 0xf00) != 0x400) {
314                 dmae_init(sh_chan);
315         }
316
317         spin_lock_bh(&sh_chan->desc_lock);
318         while (sh_chan->descs_allocated < NR_DESCS_PER_CHANNEL) {
319                 spin_unlock_bh(&sh_chan->desc_lock);
320                 desc = kzalloc(sizeof(struct sh_desc), GFP_KERNEL);
321                 if (!desc) {
322                         spin_lock_bh(&sh_chan->desc_lock);
323                         break;
324                 }
325                 dma_async_tx_descriptor_init(&desc->async_tx,
326                                         &sh_chan->common);
327                 desc->async_tx.tx_submit = sh_dmae_tx_submit;
328                 desc->mark = DESC_IDLE;
329
330                 spin_lock_bh(&sh_chan->desc_lock);
331                 list_add(&desc->node, &sh_chan->ld_free);
332                 sh_chan->descs_allocated++;
333         }
334         spin_unlock_bh(&sh_chan->desc_lock);
335
336         if (!sh_chan->descs_allocated)
337                 pm_runtime_put(sh_chan->dev);
338
339         return sh_chan->descs_allocated;
340 }
341
342 /*
343  * sh_dma_free_chan_resources - Free all resources of the channel.
344  */
345 static void sh_dmae_free_chan_resources(struct dma_chan *chan)
346 {
347         struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
348         struct sh_desc *desc, *_desc;
349         LIST_HEAD(list);
350         int descs = sh_chan->descs_allocated;
351
352         dmae_halt(sh_chan);
353
354         /* Prepared and not submitted descriptors can still be on the queue */
355         if (!list_empty(&sh_chan->ld_queue))
356                 sh_dmae_chan_ld_cleanup(sh_chan, true);
357
358         if (chan->private) {
359                 /* The caller is holding dma_list_mutex */
360                 struct sh_dmae_slave *param = chan->private;
361                 clear_bit(param->slave_id, sh_dmae_slave_used);
362         }
363
364         spin_lock_bh(&sh_chan->desc_lock);
365
366         list_splice_init(&sh_chan->ld_free, &list);
367         sh_chan->descs_allocated = 0;
368
369         spin_unlock_bh(&sh_chan->desc_lock);
370
371         if (descs > 0)
372                 pm_runtime_put(sh_chan->dev);
373
374         list_for_each_entry_safe(desc, _desc, &list, node)
375                 kfree(desc);
376 }
377
378 /**
379  * sh_dmae_add_desc - get, set up and return one transfer descriptor
380  * @sh_chan:    DMA channel
381  * @flags:      DMA transfer flags
382  * @dest:       destination DMA address, incremented when direction equals
383  *              DMA_FROM_DEVICE or DMA_BIDIRECTIONAL
384  * @src:        source DMA address, incremented when direction equals
385  *              DMA_TO_DEVICE or DMA_BIDIRECTIONAL
386  * @len:        DMA transfer length
387  * @first:      if NULL, set to the current descriptor and cookie set to -EBUSY
388  * @direction:  needed for slave DMA to decide which address to keep constant,
389  *              equals DMA_BIDIRECTIONAL for MEMCPY
390  * Returns 0 or an error
391  * Locks: called with desc_lock held
392  */
393 static struct sh_desc *sh_dmae_add_desc(struct sh_dmae_chan *sh_chan,
394         unsigned long flags, dma_addr_t *dest, dma_addr_t *src, size_t *len,
395         struct sh_desc **first, enum dma_data_direction direction)
396 {
397         struct sh_desc *new;
398         size_t copy_size;
399
400         if (!*len)
401                 return NULL;
402
403         /* Allocate the link descriptor from the free list */
404         new = sh_dmae_get_desc(sh_chan);
405         if (!new) {
406                 dev_err(sh_chan->dev, "No free link descriptor available\n");
407                 return NULL;
408         }
409
410         copy_size = min(*len, (size_t)SH_DMA_TCR_MAX + 1);
411
412         new->hw.sar = *src;
413         new->hw.dar = *dest;
414         new->hw.tcr = copy_size;
415
416         if (!*first) {
417                 /* First desc */
418                 new->async_tx.cookie = -EBUSY;
419                 *first = new;
420         } else {
421                 /* Other desc - invisible to the user */
422                 new->async_tx.cookie = -EINVAL;
423         }
424
425         dev_dbg(sh_chan->dev,
426                 "chaining (%u/%u)@%x -> %x with %p, cookie %d, shift %d\n",
427                 copy_size, *len, *src, *dest, &new->async_tx,
428                 new->async_tx.cookie, sh_chan->xmit_shift);
429
430         new->mark = DESC_PREPARED;
431         new->async_tx.flags = flags;
432         new->direction = direction;
433
434         *len -= copy_size;
435         if (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE)
436                 *src += copy_size;
437         if (direction == DMA_BIDIRECTIONAL || direction == DMA_FROM_DEVICE)
438                 *dest += copy_size;
439
440         return new;
441 }
442
443 /*
444  * sh_dmae_prep_sg - prepare transfer descriptors from an SG list
445  *
446  * Common routine for public (MEMCPY) and slave DMA. The MEMCPY case is also
447  * converted to scatter-gather to guarantee consistent locking and a correct
448  * list manipulation. For slave DMA direction carries the usual meaning, and,
449  * logically, the SG list is RAM and the addr variable contains slave address,
450  * e.g., the FIFO I/O register. For MEMCPY direction equals DMA_BIDIRECTIONAL
451  * and the SG list contains only one element and points at the source buffer.
452  */
453 static struct dma_async_tx_descriptor *sh_dmae_prep_sg(struct sh_dmae_chan *sh_chan,
454         struct scatterlist *sgl, unsigned int sg_len, dma_addr_t *addr,
455         enum dma_data_direction direction, unsigned long flags)
456 {
457         struct scatterlist *sg;
458         struct sh_desc *first = NULL, *new = NULL /* compiler... */;
459         LIST_HEAD(tx_list);
460         int chunks = 0;
461         int i;
462
463         if (!sg_len)
464                 return NULL;
465
466         for_each_sg(sgl, sg, sg_len, i)
467                 chunks += (sg_dma_len(sg) + SH_DMA_TCR_MAX) /
468                         (SH_DMA_TCR_MAX + 1);
469
470         /* Have to lock the whole loop to protect against concurrent release */
471         spin_lock_bh(&sh_chan->desc_lock);
472
473         /*
474          * Chaining:
475          * first descriptor is what user is dealing with in all API calls, its
476          *      cookie is at first set to -EBUSY, at tx-submit to a positive
477          *      number
478          * if more than one chunk is needed further chunks have cookie = -EINVAL
479          * the last chunk, if not equal to the first, has cookie = -ENOSPC
480          * all chunks are linked onto the tx_list head with their .node heads
481          *      only during this function, then they are immediately spliced
482          *      back onto the free list in form of a chain
483          */
484         for_each_sg(sgl, sg, sg_len, i) {
485                 dma_addr_t sg_addr = sg_dma_address(sg);
486                 size_t len = sg_dma_len(sg);
487
488                 if (!len)
489                         goto err_get_desc;
490
491                 do {
492                         dev_dbg(sh_chan->dev, "Add SG #%d@%p[%d], dma %llx\n",
493                                 i, sg, len, (unsigned long long)sg_addr);
494
495                         if (direction == DMA_FROM_DEVICE)
496                                 new = sh_dmae_add_desc(sh_chan, flags,
497                                                 &sg_addr, addr, &len, &first,
498                                                 direction);
499                         else
500                                 new = sh_dmae_add_desc(sh_chan, flags,
501                                                 addr, &sg_addr, &len, &first,
502                                                 direction);
503                         if (!new)
504                                 goto err_get_desc;
505
506                         new->chunks = chunks--;
507                         list_add_tail(&new->node, &tx_list);
508                 } while (len);
509         }
510
511         if (new != first)
512                 new->async_tx.cookie = -ENOSPC;
513
514         /* Put them back on the free list, so, they don't get lost */
515         list_splice_tail(&tx_list, &sh_chan->ld_free);
516
517         spin_unlock_bh(&sh_chan->desc_lock);
518
519         return &first->async_tx;
520
521 err_get_desc:
522         list_for_each_entry(new, &tx_list, node)
523                 new->mark = DESC_IDLE;
524         list_splice(&tx_list, &sh_chan->ld_free);
525
526         spin_unlock_bh(&sh_chan->desc_lock);
527
528         return NULL;
529 }
530
531 static struct dma_async_tx_descriptor *sh_dmae_prep_memcpy(
532         struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
533         size_t len, unsigned long flags)
534 {
535         struct sh_dmae_chan *sh_chan;
536         struct scatterlist sg;
537
538         if (!chan || !len)
539                 return NULL;
540
541         chan->private = NULL;
542
543         sh_chan = to_sh_chan(chan);
544
545         sg_init_table(&sg, 1);
546         sg_set_page(&sg, pfn_to_page(PFN_DOWN(dma_src)), len,
547                     offset_in_page(dma_src));
548         sg_dma_address(&sg) = dma_src;
549         sg_dma_len(&sg) = len;
550
551         return sh_dmae_prep_sg(sh_chan, &sg, 1, &dma_dest, DMA_BIDIRECTIONAL,
552                                flags);
553 }
554
555 static struct dma_async_tx_descriptor *sh_dmae_prep_slave_sg(
556         struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
557         enum dma_data_direction direction, unsigned long flags)
558 {
559         struct sh_dmae_slave *param;
560         struct sh_dmae_chan *sh_chan;
561
562         if (!chan)
563                 return NULL;
564
565         sh_chan = to_sh_chan(chan);
566         param = chan->private;
567
568         /* Someone calling slave DMA on a public channel? */
569         if (!param || !sg_len) {
570                 dev_warn(sh_chan->dev, "%s: bad parameter: %p, %d, %d\n",
571                          __func__, param, sg_len, param ? param->slave_id : -1);
572                 return NULL;
573         }
574
575         /*
576          * if (param != NULL), this is a successfully requested slave channel,
577          * therefore param->config != NULL too.
578          */
579         return sh_dmae_prep_sg(sh_chan, sgl, sg_len, &param->config->addr,
580                                direction, flags);
581 }
582
583 static void sh_dmae_terminate_all(struct dma_chan *chan)
584 {
585         struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
586
587         if (!chan)
588                 return;
589
590         dmae_halt(sh_chan);
591
592         spin_lock_bh(&sh_chan->desc_lock);
593         if (!list_empty(&sh_chan->ld_queue)) {
594                 /* Record partial transfer */
595                 struct sh_desc *desc = list_entry(sh_chan->ld_queue.next,
596                                                   struct sh_desc, node);
597                 desc->partial = (desc->hw.tcr - sh_dmae_readl(sh_chan, TCR)) <<
598                         sh_chan->xmit_shift;
599
600         }
601         spin_unlock_bh(&sh_chan->desc_lock);
602
603         sh_dmae_chan_ld_cleanup(sh_chan, true);
604 }
605
606 static dma_async_tx_callback __ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
607 {
608         struct sh_desc *desc, *_desc;
609         /* Is the "exposed" head of a chain acked? */
610         bool head_acked = false;
611         dma_cookie_t cookie = 0;
612         dma_async_tx_callback callback = NULL;
613         void *param = NULL;
614
615         spin_lock_bh(&sh_chan->desc_lock);
616         list_for_each_entry_safe(desc, _desc, &sh_chan->ld_queue, node) {
617                 struct dma_async_tx_descriptor *tx = &desc->async_tx;
618
619                 BUG_ON(tx->cookie > 0 && tx->cookie != desc->cookie);
620                 BUG_ON(desc->mark != DESC_SUBMITTED &&
621                        desc->mark != DESC_COMPLETED &&
622                        desc->mark != DESC_WAITING);
623
624                 /*
625                  * queue is ordered, and we use this loop to (1) clean up all
626                  * completed descriptors, and to (2) update descriptor flags of
627                  * any chunks in a (partially) completed chain
628                  */
629                 if (!all && desc->mark == DESC_SUBMITTED &&
630                     desc->cookie != cookie)
631                         break;
632
633                 if (tx->cookie > 0)
634                         cookie = tx->cookie;
635
636                 if (desc->mark == DESC_COMPLETED && desc->chunks == 1) {
637                         if (sh_chan->completed_cookie != desc->cookie - 1)
638                                 dev_dbg(sh_chan->dev,
639                                         "Completing cookie %d, expected %d\n",
640                                         desc->cookie,
641                                         sh_chan->completed_cookie + 1);
642                         sh_chan->completed_cookie = desc->cookie;
643                 }
644
645                 /* Call callback on the last chunk */
646                 if (desc->mark == DESC_COMPLETED && tx->callback) {
647                         desc->mark = DESC_WAITING;
648                         callback = tx->callback;
649                         param = tx->callback_param;
650                         dev_dbg(sh_chan->dev, "descriptor #%d@%p on %d callback\n",
651                                 tx->cookie, tx, sh_chan->id);
652                         BUG_ON(desc->chunks != 1);
653                         break;
654                 }
655
656                 if (tx->cookie > 0 || tx->cookie == -EBUSY) {
657                         if (desc->mark == DESC_COMPLETED) {
658                                 BUG_ON(tx->cookie < 0);
659                                 desc->mark = DESC_WAITING;
660                         }
661                         head_acked = async_tx_test_ack(tx);
662                 } else {
663                         switch (desc->mark) {
664                         case DESC_COMPLETED:
665                                 desc->mark = DESC_WAITING;
666                                 /* Fall through */
667                         case DESC_WAITING:
668                                 if (head_acked)
669                                         async_tx_ack(&desc->async_tx);
670                         }
671                 }
672
673                 dev_dbg(sh_chan->dev, "descriptor %p #%d completed.\n",
674                         tx, tx->cookie);
675
676                 if (((desc->mark == DESC_COMPLETED ||
677                       desc->mark == DESC_WAITING) &&
678                      async_tx_test_ack(&desc->async_tx)) || all) {
679                         /* Remove from ld_queue list */
680                         desc->mark = DESC_IDLE;
681                         list_move(&desc->node, &sh_chan->ld_free);
682                 }
683         }
684         spin_unlock_bh(&sh_chan->desc_lock);
685
686         if (callback)
687                 callback(param);
688
689         return callback;
690 }
691
692 /*
693  * sh_chan_ld_cleanup - Clean up link descriptors
694  *
695  * This function cleans up the ld_queue of DMA channel.
696  */
697 static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
698 {
699         while (__ld_cleanup(sh_chan, all))
700                 ;
701 }
702
703 static void sh_chan_xfer_ld_queue(struct sh_dmae_chan *sh_chan)
704 {
705         struct sh_desc *desc;
706
707         spin_lock_bh(&sh_chan->desc_lock);
708         /* DMA work check */
709         if (dmae_is_busy(sh_chan)) {
710                 spin_unlock_bh(&sh_chan->desc_lock);
711                 return;
712         }
713
714         /* Find the first not transferred desciptor */
715         list_for_each_entry(desc, &sh_chan->ld_queue, node)
716                 if (desc->mark == DESC_SUBMITTED) {
717                         dev_dbg(sh_chan->dev, "Queue #%d to %d: %u@%x -> %x\n",
718                                 desc->async_tx.cookie, sh_chan->id,
719                                 desc->hw.tcr, desc->hw.sar, desc->hw.dar);
720                         /* Get the ld start address from ld_queue */
721                         dmae_set_reg(sh_chan, &desc->hw);
722                         dmae_start(sh_chan);
723                         break;
724                 }
725
726         spin_unlock_bh(&sh_chan->desc_lock);
727 }
728
729 static void sh_dmae_memcpy_issue_pending(struct dma_chan *chan)
730 {
731         struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
732         sh_chan_xfer_ld_queue(sh_chan);
733 }
734
735 static enum dma_status sh_dmae_is_complete(struct dma_chan *chan,
736                                         dma_cookie_t cookie,
737                                         dma_cookie_t *done,
738                                         dma_cookie_t *used)
739 {
740         struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
741         dma_cookie_t last_used;
742         dma_cookie_t last_complete;
743         enum dma_status status;
744
745         sh_dmae_chan_ld_cleanup(sh_chan, false);
746
747         last_used = chan->cookie;
748         last_complete = sh_chan->completed_cookie;
749         BUG_ON(last_complete < 0);
750
751         if (done)
752                 *done = last_complete;
753
754         if (used)
755                 *used = last_used;
756
757         spin_lock_bh(&sh_chan->desc_lock);
758
759         status = dma_async_is_complete(cookie, last_complete, last_used);
760
761         /*
762          * If we don't find cookie on the queue, it has been aborted and we have
763          * to report error
764          */
765         if (status != DMA_SUCCESS) {
766                 struct sh_desc *desc;
767                 status = DMA_ERROR;
768                 list_for_each_entry(desc, &sh_chan->ld_queue, node)
769                         if (desc->cookie == cookie) {
770                                 status = DMA_IN_PROGRESS;
771                                 break;
772                         }
773         }
774
775         spin_unlock_bh(&sh_chan->desc_lock);
776
777         return status;
778 }
779
780 static irqreturn_t sh_dmae_interrupt(int irq, void *data)
781 {
782         irqreturn_t ret = IRQ_NONE;
783         struct sh_dmae_chan *sh_chan = (struct sh_dmae_chan *)data;
784         u32 chcr = sh_dmae_readl(sh_chan, CHCR);
785
786         if (chcr & CHCR_TE) {
787                 /* DMA stop */
788                 dmae_halt(sh_chan);
789
790                 ret = IRQ_HANDLED;
791                 tasklet_schedule(&sh_chan->tasklet);
792         }
793
794         return ret;
795 }
796
797 #if defined(CONFIG_CPU_SH4)
798 static irqreturn_t sh_dmae_err(int irq, void *data)
799 {
800         struct sh_dmae_device *shdev = (struct sh_dmae_device *)data;
801         int i;
802
803         /* halt the dma controller */
804         sh_dmae_ctl_stop(shdev);
805
806         /* We cannot detect, which channel caused the error, have to reset all */
807         for (i = 0; i < SH_DMAC_MAX_CHANNELS; i++) {
808                 struct sh_dmae_chan *sh_chan = shdev->chan[i];
809                 if (sh_chan) {
810                         struct sh_desc *desc;
811                         /* Stop the channel */
812                         dmae_halt(sh_chan);
813                         /* Complete all  */
814                         list_for_each_entry(desc, &sh_chan->ld_queue, node) {
815                                 struct dma_async_tx_descriptor *tx = &desc->async_tx;
816                                 desc->mark = DESC_IDLE;
817                                 if (tx->callback)
818                                         tx->callback(tx->callback_param);
819                         }
820                         list_splice_init(&sh_chan->ld_queue, &sh_chan->ld_free);
821                 }
822         }
823         sh_dmae_rst(shdev);
824
825         return IRQ_HANDLED;
826 }
827 #endif
828
829 static void dmae_do_tasklet(unsigned long data)
830 {
831         struct sh_dmae_chan *sh_chan = (struct sh_dmae_chan *)data;
832         struct sh_desc *desc;
833         u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
834         u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
835
836         spin_lock(&sh_chan->desc_lock);
837         list_for_each_entry(desc, &sh_chan->ld_queue, node) {
838                 if (desc->mark == DESC_SUBMITTED &&
839                     ((desc->direction == DMA_FROM_DEVICE &&
840                       (desc->hw.dar + desc->hw.tcr) == dar_buf) ||
841                      (desc->hw.sar + desc->hw.tcr) == sar_buf)) {
842                         dev_dbg(sh_chan->dev, "done #%d@%p dst %u\n",
843                                 desc->async_tx.cookie, &desc->async_tx,
844                                 desc->hw.dar);
845                         desc->mark = DESC_COMPLETED;
846                         break;
847                 }
848         }
849         spin_unlock(&sh_chan->desc_lock);
850
851         /* Next desc */
852         sh_chan_xfer_ld_queue(sh_chan);
853         sh_dmae_chan_ld_cleanup(sh_chan, false);
854 }
855
856 static int __devinit sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
857                                         int irq, unsigned long flags)
858 {
859         int err;
860         struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
861         struct platform_device *pdev = to_platform_device(shdev->common.dev);
862         struct sh_dmae_chan *new_sh_chan;
863
864         /* alloc channel */
865         new_sh_chan = kzalloc(sizeof(struct sh_dmae_chan), GFP_KERNEL);
866         if (!new_sh_chan) {
867                 dev_err(shdev->common.dev,
868                         "No free memory for allocating dma channels!\n");
869                 return -ENOMEM;
870         }
871
872         /* copy struct dma_device */
873         new_sh_chan->common.device = &shdev->common;
874
875         new_sh_chan->dev = shdev->common.dev;
876         new_sh_chan->id = id;
877         new_sh_chan->irq = irq;
878         new_sh_chan->base = shdev->chan_reg + chan_pdata->offset / sizeof(u32);
879
880         /* Init DMA tasklet */
881         tasklet_init(&new_sh_chan->tasklet, dmae_do_tasklet,
882                         (unsigned long)new_sh_chan);
883
884         /* Init the channel */
885         dmae_init(new_sh_chan);
886
887         spin_lock_init(&new_sh_chan->desc_lock);
888
889         /* Init descripter manage list */
890         INIT_LIST_HEAD(&new_sh_chan->ld_queue);
891         INIT_LIST_HEAD(&new_sh_chan->ld_free);
892
893         /* Add the channel to DMA device channel list */
894         list_add_tail(&new_sh_chan->common.device_node,
895                         &shdev->common.channels);
896         shdev->common.chancnt++;
897
898         if (pdev->id >= 0)
899                 snprintf(new_sh_chan->dev_id, sizeof(new_sh_chan->dev_id),
900                          "sh-dmae%d.%d", pdev->id, new_sh_chan->id);
901         else
902                 snprintf(new_sh_chan->dev_id, sizeof(new_sh_chan->dev_id),
903                          "sh-dma%d", new_sh_chan->id);
904
905         /* set up channel irq */
906         err = request_irq(irq, &sh_dmae_interrupt, flags,
907                           new_sh_chan->dev_id, new_sh_chan);
908         if (err) {
909                 dev_err(shdev->common.dev, "DMA channel %d request_irq error "
910                         "with return %d\n", id, err);
911                 goto err_no_irq;
912         }
913
914         shdev->chan[id] = new_sh_chan;
915         return 0;
916
917 err_no_irq:
918         /* remove from dmaengine device node */
919         list_del(&new_sh_chan->common.device_node);
920         kfree(new_sh_chan);
921         return err;
922 }
923
924 static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
925 {
926         int i;
927
928         for (i = shdev->common.chancnt - 1 ; i >= 0 ; i--) {
929                 if (shdev->chan[i]) {
930                         struct sh_dmae_chan *sh_chan = shdev->chan[i];
931
932                         free_irq(sh_chan->irq, sh_chan);
933
934                         list_del(&sh_chan->common.device_node);
935                         kfree(sh_chan);
936                         shdev->chan[i] = NULL;
937                 }
938         }
939         shdev->common.chancnt = 0;
940 }
941
942 static int __init sh_dmae_probe(struct platform_device *pdev)
943 {
944         struct sh_dmae_pdata *pdata = pdev->dev.platform_data;
945         unsigned long irqflags = IRQF_DISABLED,
946                 chan_flag[SH_DMAC_MAX_CHANNELS] = {};
947         int errirq, chan_irq[SH_DMAC_MAX_CHANNELS];
948         int err, i, irq_cnt = 0, irqres = 0;
949         struct sh_dmae_device *shdev;
950         struct resource *chan, *dmars, *errirq_res, *chanirq_res;
951
952         /* get platform data */
953         if (!pdata || !pdata->channel_num)
954                 return -ENODEV;
955
956         chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
957         /* DMARS area is optional, if absent, this controller cannot do slave DMA */
958         dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
959         /*
960          * IRQ resources:
961          * 1. there always must be at least one IRQ IO-resource. On SH4 it is
962          *    the error IRQ, in which case it is the only IRQ in this resource:
963          *    start == end. If it is the only IRQ resource, all channels also
964          *    use the same IRQ.
965          * 2. DMA channel IRQ resources can be specified one per resource or in
966          *    ranges (start != end)
967          * 3. iff all events (channels and, optionally, error) on this
968          *    controller use the same IRQ, only one IRQ resource can be
969          *    specified, otherwise there must be one IRQ per channel, even if
970          *    some of them are equal
971          * 4. if all IRQs on this controller are equal or if some specific IRQs
972          *    specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
973          *    requested with the IRQF_SHARED flag
974          */
975         errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
976         if (!chan || !errirq_res)
977                 return -ENODEV;
978
979         if (!request_mem_region(chan->start, resource_size(chan), pdev->name)) {
980                 dev_err(&pdev->dev, "DMAC register region already claimed\n");
981                 return -EBUSY;
982         }
983
984         if (dmars && !request_mem_region(dmars->start, resource_size(dmars), pdev->name)) {
985                 dev_err(&pdev->dev, "DMAC DMARS region already claimed\n");
986                 err = -EBUSY;
987                 goto ermrdmars;
988         }
989
990         err = -ENOMEM;
991         shdev = kzalloc(sizeof(struct sh_dmae_device), GFP_KERNEL);
992         if (!shdev) {
993                 dev_err(&pdev->dev, "Not enough memory\n");
994                 goto ealloc;
995         }
996
997         shdev->chan_reg = ioremap(chan->start, resource_size(chan));
998         if (!shdev->chan_reg)
999                 goto emapchan;
1000         if (dmars) {
1001                 shdev->dmars = ioremap(dmars->start, resource_size(dmars));
1002                 if (!shdev->dmars)
1003                         goto emapdmars;
1004         }
1005
1006         /* platform data */
1007         shdev->pdata = pdata;
1008
1009         pm_runtime_enable(&pdev->dev);
1010         pm_runtime_get_sync(&pdev->dev);
1011
1012         /* reset dma controller */
1013         err = sh_dmae_rst(shdev);
1014         if (err)
1015                 goto rst_err;
1016
1017         INIT_LIST_HEAD(&shdev->common.channels);
1018
1019         dma_cap_set(DMA_MEMCPY, shdev->common.cap_mask);
1020         if (dmars)
1021                 dma_cap_set(DMA_SLAVE, shdev->common.cap_mask);
1022
1023         shdev->common.device_alloc_chan_resources
1024                 = sh_dmae_alloc_chan_resources;
1025         shdev->common.device_free_chan_resources = sh_dmae_free_chan_resources;
1026         shdev->common.device_prep_dma_memcpy = sh_dmae_prep_memcpy;
1027         shdev->common.device_is_tx_complete = sh_dmae_is_complete;
1028         shdev->common.device_issue_pending = sh_dmae_memcpy_issue_pending;
1029
1030         /* Compulsory for DMA_SLAVE fields */
1031         shdev->common.device_prep_slave_sg = sh_dmae_prep_slave_sg;
1032         shdev->common.device_terminate_all = sh_dmae_terminate_all;
1033
1034         shdev->common.dev = &pdev->dev;
1035         /* Default transfer size of 32 bytes requires 32-byte alignment */
1036         shdev->common.copy_align = LOG2_DEFAULT_XFER_SIZE;
1037
1038 #if defined(CONFIG_CPU_SH4)
1039         chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
1040
1041         if (!chanirq_res)
1042                 chanirq_res = errirq_res;
1043         else
1044                 irqres++;
1045
1046         if (chanirq_res == errirq_res ||
1047             (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
1048                 irqflags = IRQF_SHARED;
1049
1050         errirq = errirq_res->start;
1051
1052         err = request_irq(errirq, sh_dmae_err, irqflags,
1053                           "DMAC Address Error", shdev);
1054         if (err) {
1055                 dev_err(&pdev->dev,
1056                         "DMA failed requesting irq #%d, error %d\n",
1057                         errirq, err);
1058                 goto eirq_err;
1059         }
1060
1061 #else
1062         chanirq_res = errirq_res;
1063 #endif /* CONFIG_CPU_SH4 */
1064
1065         if (chanirq_res->start == chanirq_res->end &&
1066             !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
1067                 /* Special case - all multiplexed */
1068                 for (; irq_cnt < pdata->channel_num; irq_cnt++) {
1069                         chan_irq[irq_cnt] = chanirq_res->start;
1070                         chan_flag[irq_cnt] = IRQF_SHARED;
1071                 }
1072         } else {
1073                 do {
1074                         for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
1075                                 if ((errirq_res->flags & IORESOURCE_BITS) ==
1076                                     IORESOURCE_IRQ_SHAREABLE)
1077                                         chan_flag[irq_cnt] = IRQF_SHARED;
1078                                 else
1079                                         chan_flag[irq_cnt] = IRQF_DISABLED;
1080                                 dev_dbg(&pdev->dev,
1081                                         "Found IRQ %d for channel %d\n",
1082                                         i, irq_cnt);
1083                                 chan_irq[irq_cnt++] = i;
1084                         }
1085                         chanirq_res = platform_get_resource(pdev,
1086                                                 IORESOURCE_IRQ, ++irqres);
1087                 } while (irq_cnt < pdata->channel_num && chanirq_res);
1088         }
1089
1090         if (irq_cnt < pdata->channel_num)
1091                 goto eirqres;
1092
1093         /* Create DMA Channel */
1094         for (i = 0; i < pdata->channel_num; i++) {
1095                 err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
1096                 if (err)
1097                         goto chan_probe_err;
1098         }
1099
1100         pm_runtime_put(&pdev->dev);
1101
1102         platform_set_drvdata(pdev, shdev);
1103         dma_async_device_register(&shdev->common);
1104
1105         return err;
1106
1107 chan_probe_err:
1108         sh_dmae_chan_remove(shdev);
1109 eirqres:
1110 #if defined(CONFIG_CPU_SH4)
1111         free_irq(errirq, shdev);
1112 eirq_err:
1113 #endif
1114 rst_err:
1115         pm_runtime_put(&pdev->dev);
1116         if (dmars)
1117                 iounmap(shdev->dmars);
1118 emapdmars:
1119         iounmap(shdev->chan_reg);
1120 emapchan:
1121         kfree(shdev);
1122 ealloc:
1123         if (dmars)
1124                 release_mem_region(dmars->start, resource_size(dmars));
1125 ermrdmars:
1126         release_mem_region(chan->start, resource_size(chan));
1127
1128         return err;
1129 }
1130
1131 static int __exit sh_dmae_remove(struct platform_device *pdev)
1132 {
1133         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
1134         struct resource *res;
1135         int errirq = platform_get_irq(pdev, 0);
1136
1137         dma_async_device_unregister(&shdev->common);
1138
1139         if (errirq > 0)
1140                 free_irq(errirq, shdev);
1141
1142         /* channel data remove */
1143         sh_dmae_chan_remove(shdev);
1144
1145         pm_runtime_disable(&pdev->dev);
1146
1147         if (shdev->dmars)
1148                 iounmap(shdev->dmars);
1149         iounmap(shdev->chan_reg);
1150
1151         kfree(shdev);
1152
1153         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1154         if (res)
1155                 release_mem_region(res->start, resource_size(res));
1156         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1157         if (res)
1158                 release_mem_region(res->start, resource_size(res));
1159
1160         return 0;
1161 }
1162
1163 static void sh_dmae_shutdown(struct platform_device *pdev)
1164 {
1165         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
1166         sh_dmae_ctl_stop(shdev);
1167 }
1168
1169 static struct platform_driver sh_dmae_driver = {
1170         .remove         = __exit_p(sh_dmae_remove),
1171         .shutdown       = sh_dmae_shutdown,
1172         .driver = {
1173                 .name   = "sh-dma-engine",
1174         },
1175 };
1176
1177 static int __init sh_dmae_init(void)
1178 {
1179         return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
1180 }
1181 module_init(sh_dmae_init);
1182
1183 static void __exit sh_dmae_exit(void)
1184 {
1185         platform_driver_unregister(&sh_dmae_driver);
1186 }
1187 module_exit(sh_dmae_exit);
1188
1189 MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
1190 MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
1191 MODULE_LICENSE("GPL");