projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Merge tag 'dm-4.8-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device...
[deliverable/linux.git] / drivers / dma / sa11x0-dma.c
1 /*
2 * SA11x0 DMAengine support
3 *
4 * Copyright (C) 2012 Russell King
5 * Derived in part from arch/arm/mach-sa1100/dma.c,
6 * Copyright (C) 2000, 2001 by Nicolas Pitre
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12 #include <linux/sched.h>
13 #include <linux/device.h>
14 #include <linux/dmaengine.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/sa11x0-dma.h>
21 #include <linux/slab.h>
22 #include <linux/spinlock.h>
23
24 #include "virt-dma.h"
25
26 #define NR_PHY_CHAN 6
27 #define DMA_ALIGN 3
28 #define DMA_MAX_SIZE 0x1fff
29 #define DMA_CHUNK_SIZE 0x1000
30
31 #define DMA_DDAR 0x00
32 #define DMA_DCSR_S 0x04
33 #define DMA_DCSR_C 0x08
34 #define DMA_DCSR_R 0x0c
35 #define DMA_DBSA 0x10
36 #define DMA_DBTA 0x14
37 #define DMA_DBSB 0x18
38 #define DMA_DBTB 0x1c
39 #define DMA_SIZE 0x20
40
41 #define DCSR_RUN (1 << 0)
42 #define DCSR_IE (1 << 1)
43 #define DCSR_ERROR (1 << 2)
44 #define DCSR_DONEA (1 << 3)
45 #define DCSR_STRTA (1 << 4)
46 #define DCSR_DONEB (1 << 5)
47 #define DCSR_STRTB (1 << 6)
48 #define DCSR_BIU (1 << 7)
49
50 #define DDAR_RW (1 << 0) /* 0 = W, 1 = R */
51 #define DDAR_E (1 << 1) /* 0 = LE, 1 = BE */
52 #define DDAR_BS (1 << 2) /* 0 = BS4, 1 = BS8 */
53 #define DDAR_DW (1 << 3) /* 0 = 8b, 1 = 16b */
54 #define DDAR_Ser0UDCTr (0x0 << 4)
55 #define DDAR_Ser0UDCRc (0x1 << 4)
56 #define DDAR_Ser1SDLCTr (0x2 << 4)
57 #define DDAR_Ser1SDLCRc (0x3 << 4)
58 #define DDAR_Ser1UARTTr (0x4 << 4)
59 #define DDAR_Ser1UARTRc (0x5 << 4)
60 #define DDAR_Ser2ICPTr (0x6 << 4)
61 #define DDAR_Ser2ICPRc (0x7 << 4)
62 #define DDAR_Ser3UARTTr (0x8 << 4)
63 #define DDAR_Ser3UARTRc (0x9 << 4)
64 #define DDAR_Ser4MCP0Tr (0xa << 4)
65 #define DDAR_Ser4MCP0Rc (0xb << 4)
66 #define DDAR_Ser4MCP1Tr (0xc << 4)
67 #define DDAR_Ser4MCP1Rc (0xd << 4)
68 #define DDAR_Ser4SSPTr (0xe << 4)
69 #define DDAR_Ser4SSPRc (0xf << 4)
70
71 struct sa11x0_dma_sg {
72 u32 addr;
73 u32 len;
74 };
75
76 struct sa11x0_dma_desc {
77 struct virt_dma_desc vd;
78
79 u32 ddar;
80 size_t size;
81 unsigned period;
82 bool cyclic;
83
84 unsigned sglen;
85 struct sa11x0_dma_sg sg[0];
86 };
87
88 struct sa11x0_dma_phy;
89
90 struct sa11x0_dma_chan {
91 struct virt_dma_chan vc;
92
93 /* protected by c->vc.lock */
94 struct sa11x0_dma_phy *phy;
95 enum dma_status status;
96
97 /* protected by d->lock */
98 struct list_head node;
99
100 u32 ddar;
101 const char *name;
102 };
103
104 struct sa11x0_dma_phy {
105 void __iomem *base;
106 struct sa11x0_dma_dev *dev;
107 unsigned num;
108
109 struct sa11x0_dma_chan *vchan;
110
111 /* Protected by c->vc.lock */
112 unsigned sg_load;
113 struct sa11x0_dma_desc *txd_load;
114 unsigned sg_done;
115 struct sa11x0_dma_desc *txd_done;
116 u32 dbs[2];
117 u32 dbt[2];
118 u32 dcsr;
119 };
120
121 struct sa11x0_dma_dev {
122 struct dma_device slave;
123 void __iomem *base;
124 spinlock_t lock;
125 struct tasklet_struct task;
126 struct list_head chan_pending;
127 struct sa11x0_dma_phy phy[NR_PHY_CHAN];
128 };
129
130 static struct sa11x0_dma_chan *to_sa11x0_dma_chan(struct dma_chan *chan)
131 {
132 return container_of(chan, struct sa11x0_dma_chan, vc.chan);
133 }
134
135 static struct sa11x0_dma_dev *to_sa11x0_dma(struct dma_device *dmadev)
136 {
137 return container_of(dmadev, struct sa11x0_dma_dev, slave);
138 }
139
140 static struct sa11x0_dma_desc *sa11x0_dma_next_desc(struct sa11x0_dma_chan *c)
141 {
142 struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
143
144 return vd ? container_of(vd, struct sa11x0_dma_desc, vd) : NULL;
145 }
146
147 static void sa11x0_dma_free_desc(struct virt_dma_desc *vd)
148 {
149 kfree(container_of(vd, struct sa11x0_dma_desc, vd));
150 }
151
152 static void sa11x0_dma_start_desc(struct sa11x0_dma_phy *p, struct sa11x0_dma_desc *txd)
153 {
154 list_del(&txd->vd.node);
155 p->txd_load = txd;
156 p->sg_load = 0;
157
158 dev_vdbg(p->dev->slave.dev, "pchan %u: txd %p[%x]: starting: DDAR:%x\n",
159 p->num, &txd->vd, txd->vd.tx.cookie, txd->ddar);
160 }
161
162 static void noinline sa11x0_dma_start_sg(struct sa11x0_dma_phy *p,
163 struct sa11x0_dma_chan *c)
164 {
165 struct sa11x0_dma_desc *txd = p->txd_load;
166 struct sa11x0_dma_sg *sg;
167 void __iomem *base = p->base;
168 unsigned dbsx, dbtx;
169 u32 dcsr;
170
171 if (!txd)
172 return;
173
174 dcsr = readl_relaxed(base + DMA_DCSR_R);
175
176 /* Don't try to load the next transfer if both buffers are started */
177 if ((dcsr & (DCSR_STRTA | DCSR_STRTB)) == (DCSR_STRTA | DCSR_STRTB))
178 return;
179
180 if (p->sg_load == txd->sglen) {
181 if (!txd->cyclic) {
182 struct sa11x0_dma_desc *txn = sa11x0_dma_next_desc(c);
183
184 /*
185 * We have reached the end of the current descriptor.
186 * Peek at the next descriptor, and if compatible with
187 * the current, start processing it.
188 */
189 if (txn && txn->ddar == txd->ddar) {
190 txd = txn;
191 sa11x0_dma_start_desc(p, txn);
192 } else {
193 p->txd_load = NULL;
194 return;
195 }
196 } else {
197 /* Cyclic: reset back to beginning */
198 p->sg_load = 0;
199 }
200 }
201
202 sg = &txd->sg[p->sg_load++];
203
204 /* Select buffer to load according to channel status */
205 if (((dcsr & (DCSR_BIU | DCSR_STRTB)) == (DCSR_BIU | DCSR_STRTB)) ||
206 ((dcsr & (DCSR_BIU | DCSR_STRTA)) == 0)) {
207 dbsx = DMA_DBSA;
208 dbtx = DMA_DBTA;
209 dcsr = DCSR_STRTA | DCSR_IE | DCSR_RUN;
210 } else {
211 dbsx = DMA_DBSB;
212 dbtx = DMA_DBTB;
213 dcsr = DCSR_STRTB | DCSR_IE | DCSR_RUN;
214 }
215
216 writel_relaxed(sg->addr, base + dbsx);
217 writel_relaxed(sg->len, base + dbtx);
218 writel(dcsr, base + DMA_DCSR_S);
219
220 dev_dbg(p->dev->slave.dev, "pchan %u: load: DCSR:%02x DBS%c:%08x DBT%c:%08x\n",
221 p->num, dcsr,
222 'A' + (dbsx == DMA_DBSB), sg->addr,
223 'A' + (dbtx == DMA_DBTB), sg->len);
224 }
225
226 static void noinline sa11x0_dma_complete(struct sa11x0_dma_phy *p,
227 struct sa11x0_dma_chan *c)
228 {
229 struct sa11x0_dma_desc *txd = p->txd_done;
230
231 if (++p->sg_done == txd->sglen) {
232 if (!txd->cyclic) {
233 vchan_cookie_complete(&txd->vd);
234
235 p->sg_done = 0;
236 p->txd_done = p->txd_load;
237
238 if (!p->txd_done)
239 tasklet_schedule(&p->dev->task);
240 } else {
241 if ((p->sg_done % txd->period) == 0)
242 vchan_cyclic_callback(&txd->vd);
243
244 /* Cyclic: reset back to beginning */
245 p->sg_done = 0;
246 }
247 }
248
249 sa11x0_dma_start_sg(p, c);
250 }
251
252 static irqreturn_t sa11x0_dma_irq(int irq, void *dev_id)
253 {
254 struct sa11x0_dma_phy *p = dev_id;
255 struct sa11x0_dma_dev *d = p->dev;
256 struct sa11x0_dma_chan *c;
257 u32 dcsr;
258
259 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
260 if (!(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB)))
261 return IRQ_NONE;
262
263 /* Clear reported status bits */
264 writel_relaxed(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB),
265 p->base + DMA_DCSR_C);
266
267 dev_dbg(d->slave.dev, "pchan %u: irq: DCSR:%02x\n", p->num, dcsr);
268
269 if (dcsr & DCSR_ERROR) {
270 dev_err(d->slave.dev, "pchan %u: error. DCSR:%02x DDAR:%08x DBSA:%08x DBTA:%08x DBSB:%08x DBTB:%08x\n",
271 p->num, dcsr,
272 readl_relaxed(p->base + DMA_DDAR),
273 readl_relaxed(p->base + DMA_DBSA),
274 readl_relaxed(p->base + DMA_DBTA),
275 readl_relaxed(p->base + DMA_DBSB),
276 readl_relaxed(p->base + DMA_DBTB));
277 }
278
279 c = p->vchan;
280 if (c) {
281 unsigned long flags;
282
283 spin_lock_irqsave(&c->vc.lock, flags);
284 /*
285 * Now that we're holding the lock, check that the vchan
286 * really is associated with this pchan before touching the
287 * hardware. This should always succeed, because we won't
288 * change p->vchan or c->phy while the channel is actively
289 * transferring.
290 */
291 if (c->phy == p) {
292 if (dcsr & DCSR_DONEA)
293 sa11x0_dma_complete(p, c);
294 if (dcsr & DCSR_DONEB)
295 sa11x0_dma_complete(p, c);
296 }
297 spin_unlock_irqrestore(&c->vc.lock, flags);
298 }
299
300 return IRQ_HANDLED;
301 }
302
303 static void sa11x0_dma_start_txd(struct sa11x0_dma_chan *c)
304 {
305 struct sa11x0_dma_desc *txd = sa11x0_dma_next_desc(c);
306
307 /* If the issued list is empty, we have no further txds to process */
308 if (txd) {
309 struct sa11x0_dma_phy *p = c->phy;
310
311 sa11x0_dma_start_desc(p, txd);
312 p->txd_done = txd;
313 p->sg_done = 0;
314
315 /* The channel should not have any transfers started */
316 WARN_ON(readl_relaxed(p->base + DMA_DCSR_R) &
317 (DCSR_STRTA | DCSR_STRTB));
318
319 /* Clear the run and start bits before changing DDAR */
320 writel_relaxed(DCSR_RUN | DCSR_STRTA | DCSR_STRTB,
321 p->base + DMA_DCSR_C);
322 writel_relaxed(txd->ddar, p->base + DMA_DDAR);
323
324 /* Try to start both buffers */
325 sa11x0_dma_start_sg(p, c);
326 sa11x0_dma_start_sg(p, c);
327 }
328 }
329
330 static void sa11x0_dma_tasklet(unsigned long arg)
331 {
332 struct sa11x0_dma_dev *d = (struct sa11x0_dma_dev *)arg;
333 struct sa11x0_dma_phy *p;
334 struct sa11x0_dma_chan *c;
335 unsigned pch, pch_alloc = 0;
336
337 dev_dbg(d->slave.dev, "tasklet enter\n");
338
339 list_for_each_entry(c, &d->slave.channels, vc.chan.device_node) {
340 spin_lock_irq(&c->vc.lock);
341 p = c->phy;
342 if (p && !p->txd_done) {
343 sa11x0_dma_start_txd(c);
344 if (!p->txd_done) {
345 /* No current txd associated with this channel */
346 dev_dbg(d->slave.dev, "pchan %u: free\n", p->num);
347
348 /* Mark this channel free */
349 c->phy = NULL;
350 p->vchan = NULL;
351 }
352 }
353 spin_unlock_irq(&c->vc.lock);
354 }
355
356 spin_lock_irq(&d->lock);
357 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
358 p = &d->phy[pch];
359
360 if (p->vchan == NULL && !list_empty(&d->chan_pending)) {
361 c = list_first_entry(&d->chan_pending,
362 struct sa11x0_dma_chan, node);
363 list_del_init(&c->node);
364
365 pch_alloc |= 1 << pch;
366
367 /* Mark this channel allocated */
368 p->vchan = c;
369
370 dev_dbg(d->slave.dev, "pchan %u: alloc vchan %p\n", pch, &c->vc);
371 }
372 }
373 spin_unlock_irq(&d->lock);
374
375 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
376 if (pch_alloc & (1 << pch)) {
377 p = &d->phy[pch];
378 c = p->vchan;
379
380 spin_lock_irq(&c->vc.lock);
381 c->phy = p;
382
383 sa11x0_dma_start_txd(c);
384 spin_unlock_irq(&c->vc.lock);
385 }
386 }
387
388 dev_dbg(d->slave.dev, "tasklet exit\n");
389 }
390
391
392 static void sa11x0_dma_free_chan_resources(struct dma_chan *chan)
393 {
394 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
395 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
396 unsigned long flags;
397
398 spin_lock_irqsave(&d->lock, flags);
399 list_del_init(&c->node);
400 spin_unlock_irqrestore(&d->lock, flags);
401
402 vchan_free_chan_resources(&c->vc);
403 }
404
405 static dma_addr_t sa11x0_dma_pos(struct sa11x0_dma_phy *p)
406 {
407 unsigned reg;
408 u32 dcsr;
409
410 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
411
412 if ((dcsr & (DCSR_BIU | DCSR_STRTA)) == DCSR_STRTA ||
413 (dcsr & (DCSR_BIU | DCSR_STRTB)) == DCSR_BIU)
414 reg = DMA_DBSA;
415 else
416 reg = DMA_DBSB;
417
418 return readl_relaxed(p->base + reg);
419 }
420
421 static enum dma_status sa11x0_dma_tx_status(struct dma_chan *chan,
422 dma_cookie_t cookie, struct dma_tx_state *state)
423 {
424 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
425 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
426 struct sa11x0_dma_phy *p;
427 struct virt_dma_desc *vd;
428 unsigned long flags;
429 enum dma_status ret;
430
431 ret = dma_cookie_status(&c->vc.chan, cookie, state);
432 if (ret == DMA_COMPLETE)
433 return ret;
434
435 if (!state)
436 return c->status;
437
438 spin_lock_irqsave(&c->vc.lock, flags);
439 p = c->phy;
440
441 /*
442 * If the cookie is on our issue queue, then the residue is
443 * its total size.
444 */
445 vd = vchan_find_desc(&c->vc, cookie);
446 if (vd) {
447 state->residue = container_of(vd, struct sa11x0_dma_desc, vd)->size;
448 } else if (!p) {
449 state->residue = 0;
450 } else {
451 struct sa11x0_dma_desc *txd;
452 size_t bytes = 0;
453
454 if (p->txd_done && p->txd_done->vd.tx.cookie == cookie)
455 txd = p->txd_done;
456 else if (p->txd_load && p->txd_load->vd.tx.cookie == cookie)
457 txd = p->txd_load;
458 else
459 txd = NULL;
460
461 ret = c->status;
462 if (txd) {
463 dma_addr_t addr = sa11x0_dma_pos(p);
464 unsigned i;
465
466 dev_vdbg(d->slave.dev, "tx_status: addr:%x\n", addr);
467
468 for (i = 0; i < txd->sglen; i++) {
469 dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x\n",
470 i, txd->sg[i].addr, txd->sg[i].len);
471 if (addr >= txd->sg[i].addr &&
472 addr < txd->sg[i].addr + txd->sg[i].len) {
473 unsigned len;
474
475 len = txd->sg[i].len -
476 (addr - txd->sg[i].addr);
477 dev_vdbg(d->slave.dev, "tx_status: [%u] +%x\n",
478 i, len);
479 bytes += len;
480 i++;
481 break;
482 }
483 }
484 for (; i < txd->sglen; i++) {
485 dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x ++\n",
486 i, txd->sg[i].addr, txd->sg[i].len);
487 bytes += txd->sg[i].len;
488 }
489 }
490 state->residue = bytes;
491 }
492 spin_unlock_irqrestore(&c->vc.lock, flags);
493
494 dev_vdbg(d->slave.dev, "tx_status: bytes 0x%zx\n", state->residue);
495
496 return ret;
497 }
498
499 /*
500 * Move pending txds to the issued list, and re-init pending list.
501 * If not already pending, add this channel to the list of pending
502 * channels and trigger the tasklet to run.
503 */
504 static void sa11x0_dma_issue_pending(struct dma_chan *chan)
505 {
506 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
507 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
508 unsigned long flags;
509
510 spin_lock_irqsave(&c->vc.lock, flags);
511 if (vchan_issue_pending(&c->vc)) {
512 if (!c->phy) {
513 spin_lock(&d->lock);
514 if (list_empty(&c->node)) {
515 list_add_tail(&c->node, &d->chan_pending);
516 tasklet_schedule(&d->task);
517 dev_dbg(d->slave.dev, "vchan %p: issued\n", &c->vc);
518 }
519 spin_unlock(&d->lock);
520 }
521 } else
522 dev_dbg(d->slave.dev, "vchan %p: nothing to issue\n", &c->vc);
523 spin_unlock_irqrestore(&c->vc.lock, flags);
524 }
525
526 static struct dma_async_tx_descriptor *sa11x0_dma_prep_slave_sg(
527 struct dma_chan *chan, struct scatterlist *sg, unsigned int sglen,
528 enum dma_transfer_direction dir, unsigned long flags, void *context)
529 {
530 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
531 struct sa11x0_dma_desc *txd;
532 struct scatterlist *sgent;
533 unsigned i, j = sglen;
534 size_t size = 0;
535
536 /* SA11x0 channels can only operate in their native direction */
537 if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) {
538 dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n",
539 &c->vc, c->ddar, dir);
540 return NULL;
541 }
542
543 /* Do not allow zero-sized txds */
544 if (sglen == 0)
545 return NULL;
546
547 for_each_sg(sg, sgent, sglen, i) {
548 dma_addr_t addr = sg_dma_address(sgent);
549 unsigned int len = sg_dma_len(sgent);
550
551 if (len > DMA_MAX_SIZE)
552 j += DIV_ROUND_UP(len, DMA_MAX_SIZE & ~DMA_ALIGN) - 1;
553 if (addr & DMA_ALIGN) {
554 dev_dbg(chan->device->dev, "vchan %p: bad buffer alignment: %08x\n",
555 &c->vc, addr);
556 return NULL;
557 }
558 }
559
560 txd = kzalloc(sizeof(*txd) + j * sizeof(txd->sg[0]), GFP_ATOMIC);
561 if (!txd) {
562 dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc);
563 return NULL;
564 }
565
566 j = 0;
567 for_each_sg(sg, sgent, sglen, i) {
568 dma_addr_t addr = sg_dma_address(sgent);
569 unsigned len = sg_dma_len(sgent);
570
571 size += len;
572
573 do {
574 unsigned tlen = len;
575
576 /*
577 * Check whether the transfer will fit. If not, try
578 * to split the transfer up such that we end up with
579 * equal chunks - but make sure that we preserve the
580 * alignment. This avoids small segments.
581 */
582 if (tlen > DMA_MAX_SIZE) {
583 unsigned mult = DIV_ROUND_UP(tlen,
584 DMA_MAX_SIZE & ~DMA_ALIGN);
585
586 tlen = (tlen / mult) & ~DMA_ALIGN;
587 }
588
589 txd->sg[j].addr = addr;
590 txd->sg[j].len = tlen;
591
592 addr += tlen;
593 len -= tlen;
594 j++;
595 } while (len);
596 }
597
598 txd->ddar = c->ddar;
599 txd->size = size;
600 txd->sglen = j;
601
602 dev_dbg(chan->device->dev, "vchan %p: txd %p: size %u nr %u\n",
603 &c->vc, &txd->vd, txd->size, txd->sglen);
604
605 return vchan_tx_prep(&c->vc, &txd->vd, flags);
606 }
607
608 static struct dma_async_tx_descriptor *sa11x0_dma_prep_dma_cyclic(
609 struct dma_chan *chan, dma_addr_t addr, size_t size, size_t period,
610 enum dma_transfer_direction dir, unsigned long flags)
611 {
612 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
613 struct sa11x0_dma_desc *txd;
614 unsigned i, j, k, sglen, sgperiod;
615
616 /* SA11x0 channels can only operate in their native direction */
617 if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) {
618 dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n",
619 &c->vc, c->ddar, dir);
620 return NULL;
621 }
622
623 sgperiod = DIV_ROUND_UP(period, DMA_MAX_SIZE & ~DMA_ALIGN);
624 sglen = size * sgperiod / period;
625
626 /* Do not allow zero-sized txds */
627 if (sglen == 0)
628 return NULL;
629
630 txd = kzalloc(sizeof(*txd) + sglen * sizeof(txd->sg[0]), GFP_ATOMIC);
631 if (!txd) {
632 dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc);
633 return NULL;
634 }
635
636 for (i = k = 0; i < size / period; i++) {
637 size_t tlen, len = period;
638
639 for (j = 0; j < sgperiod; j++, k++) {
640 tlen = len;
641
642 if (tlen > DMA_MAX_SIZE) {
643 unsigned mult = DIV_ROUND_UP(tlen, DMA_MAX_SIZE & ~DMA_ALIGN);
644 tlen = (tlen / mult) & ~DMA_ALIGN;
645 }
646
647 txd->sg[k].addr = addr;
648 txd->sg[k].len = tlen;
649 addr += tlen;
650 len -= tlen;
651 }
652
653 WARN_ON(len != 0);
654 }
655
656 WARN_ON(k != sglen);
657
658 txd->ddar = c->ddar;
659 txd->size = size;
660 txd->sglen = sglen;
661 txd->cyclic = 1;
662 txd->period = sgperiod;
663
664 return vchan_tx_prep(&c->vc, &txd->vd, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
665 }
666
667 static int sa11x0_dma_device_config(struct dma_chan *chan,
668 struct dma_slave_config *cfg)
669 {
670 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
671 u32 ddar = c->ddar & ((0xf << 4) | DDAR_RW);
672 dma_addr_t addr;
673 enum dma_slave_buswidth width;
674 u32 maxburst;
675
676 if (ddar & DDAR_RW) {
677 addr = cfg->src_addr;
678 width = cfg->src_addr_width;
679 maxburst = cfg->src_maxburst;
680 } else {
681 addr = cfg->dst_addr;
682 width = cfg->dst_addr_width;
683 maxburst = cfg->dst_maxburst;
684 }
685
686 if ((width != DMA_SLAVE_BUSWIDTH_1_BYTE &&
687 width != DMA_SLAVE_BUSWIDTH_2_BYTES) ||
688 (maxburst != 4 && maxburst != 8))
689 return -EINVAL;
690
691 if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
692 ddar |= DDAR_DW;
693 if (maxburst == 8)
694 ddar |= DDAR_BS;
695
696 dev_dbg(c->vc.chan.device->dev, "vchan %p: dma_slave_config addr %x width %u burst %u\n",
697 &c->vc, addr, width, maxburst);
698
699 c->ddar = ddar | (addr & 0xf0000000) | (addr & 0x003ffffc) << 6;
700
701 return 0;
702 }
703
704 static int sa11x0_dma_device_pause(struct dma_chan *chan)
705 {
706 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
707 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
708 struct sa11x0_dma_phy *p;
709 LIST_HEAD(head);
710 unsigned long flags;
711
712 dev_dbg(d->slave.dev, "vchan %p: pause\n", &c->vc);
713 spin_lock_irqsave(&c->vc.lock, flags);
714 if (c->status == DMA_IN_PROGRESS) {
715 c->status = DMA_PAUSED;
716
717 p = c->phy;
718 if (p) {
719 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C);
720 } else {
721 spin_lock(&d->lock);
722 list_del_init(&c->node);
723 spin_unlock(&d->lock);
724 }
725 }
726 spin_unlock_irqrestore(&c->vc.lock, flags);
727
728 return 0;
729 }
730
731 static int sa11x0_dma_device_resume(struct dma_chan *chan)
732 {
733 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
734 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
735 struct sa11x0_dma_phy *p;
736 LIST_HEAD(head);
737 unsigned long flags;
738
739 dev_dbg(d->slave.dev, "vchan %p: resume\n", &c->vc);
740 spin_lock_irqsave(&c->vc.lock, flags);
741 if (c->status == DMA_PAUSED) {
742 c->status = DMA_IN_PROGRESS;
743
744 p = c->phy;
745 if (p) {
746 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_S);
747 } else if (!list_empty(&c->vc.desc_issued)) {
748 spin_lock(&d->lock);
749 list_add_tail(&c->node, &d->chan_pending);
750 spin_unlock(&d->lock);
751 }
752 }
753 spin_unlock_irqrestore(&c->vc.lock, flags);
754
755 return 0;
756 }
757
758 static int sa11x0_dma_device_terminate_all(struct dma_chan *chan)
759 {
760 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
761 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
762 struct sa11x0_dma_phy *p;
763 LIST_HEAD(head);
764 unsigned long flags;
765
766 dev_dbg(d->slave.dev, "vchan %p: terminate all\n", &c->vc);
767 /* Clear the tx descriptor lists */
768 spin_lock_irqsave(&c->vc.lock, flags);
769 vchan_get_all_descriptors(&c->vc, &head);
770
771 p = c->phy;
772 if (p) {
773 dev_dbg(d->slave.dev, "pchan %u: terminating\n", p->num);
774 /* vchan is assigned to a pchan - stop the channel */
775 writel(DCSR_RUN | DCSR_IE |
776 DCSR_STRTA | DCSR_DONEA |
777 DCSR_STRTB | DCSR_DONEB,
778 p->base + DMA_DCSR_C);
779
780 if (p->txd_load) {
781 if (p->txd_load != p->txd_done)
782 list_add_tail(&p->txd_load->vd.node, &head);
783 p->txd_load = NULL;
784 }
785 if (p->txd_done) {
786 list_add_tail(&p->txd_done->vd.node, &head);
787 p->txd_done = NULL;
788 }
789 c->phy = NULL;
790 spin_lock(&d->lock);
791 p->vchan = NULL;
792 spin_unlock(&d->lock);
793 tasklet_schedule(&d->task);
794 }
795 spin_unlock_irqrestore(&c->vc.lock, flags);
796 vchan_dma_desc_free_list(&c->vc, &head);
797
798 return 0;
799 }
800
801 struct sa11x0_dma_channel_desc {
802 u32 ddar;
803 const char *name;
804 };
805
806 #define CD(d1, d2) { .ddar = DDAR_##d1 | d2, .name = #d1 }
807 static const struct sa11x0_dma_channel_desc chan_desc[] = {
808 CD(Ser0UDCTr, 0),
809 CD(Ser0UDCRc, DDAR_RW),
810 CD(Ser1SDLCTr, 0),
811 CD(Ser1SDLCRc, DDAR_RW),
812 CD(Ser1UARTTr, 0),
813 CD(Ser1UARTRc, DDAR_RW),
814 CD(Ser2ICPTr, 0),
815 CD(Ser2ICPRc, DDAR_RW),
816 CD(Ser3UARTTr, 0),
817 CD(Ser3UARTRc, DDAR_RW),
818 CD(Ser4MCP0Tr, 0),
819 CD(Ser4MCP0Rc, DDAR_RW),
820 CD(Ser4MCP1Tr, 0),
821 CD(Ser4MCP1Rc, DDAR_RW),
822 CD(Ser4SSPTr, 0),
823 CD(Ser4SSPRc, DDAR_RW),
824 };
825
826 static int sa11x0_dma_init_dmadev(struct dma_device *dmadev,
827 struct device *dev)
828 {
829 unsigned i;
830
831 INIT_LIST_HEAD(&dmadev->channels);
832 dmadev->dev = dev;
833 dmadev->device_free_chan_resources = sa11x0_dma_free_chan_resources;
834 dmadev->device_config = sa11x0_dma_device_config;
835 dmadev->device_pause = sa11x0_dma_device_pause;
836 dmadev->device_resume = sa11x0_dma_device_resume;
837 dmadev->device_terminate_all = sa11x0_dma_device_terminate_all;
838 dmadev->device_tx_status = sa11x0_dma_tx_status;
839 dmadev->device_issue_pending = sa11x0_dma_issue_pending;
840
841 for (i = 0; i < ARRAY_SIZE(chan_desc); i++) {
842 struct sa11x0_dma_chan *c;
843
844 c = kzalloc(sizeof(*c), GFP_KERNEL);
845 if (!c) {
846 dev_err(dev, "no memory for channel %u\n", i);
847 return -ENOMEM;
848 }
849
850 c->status = DMA_IN_PROGRESS;
851 c->ddar = chan_desc[i].ddar;
852 c->name = chan_desc[i].name;
853 INIT_LIST_HEAD(&c->node);
854
855 c->vc.desc_free = sa11x0_dma_free_desc;
856 vchan_init(&c->vc, dmadev);
857 }
858
859 return dma_async_device_register(dmadev);
860 }
861
862 static int sa11x0_dma_request_irq(struct platform_device *pdev, int nr,
863 void *data)
864 {
865 int irq = platform_get_irq(pdev, nr);
866
867 if (irq <= 0)
868 return -ENXIO;
869
870 return request_irq(irq, sa11x0_dma_irq, 0, dev_name(&pdev->dev), data);
871 }
872
873 static void sa11x0_dma_free_irq(struct platform_device *pdev, int nr,
874 void *data)
875 {
876 int irq = platform_get_irq(pdev, nr);
877 if (irq > 0)
878 free_irq(irq, data);
879 }
880
881 static void sa11x0_dma_free_channels(struct dma_device *dmadev)
882 {
883 struct sa11x0_dma_chan *c, *cn;
884
885 list_for_each_entry_safe(c, cn, &dmadev->channels, vc.chan.device_node) {
886 list_del(&c->vc.chan.device_node);
887 tasklet_kill(&c->vc.task);
888 kfree(c);
889 }
890 }
891
892 static int sa11x0_dma_probe(struct platform_device *pdev)
893 {
894 struct sa11x0_dma_dev *d;
895 struct resource *res;
896 unsigned i;
897 int ret;
898
899 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
900 if (!res)
901 return -ENXIO;
902
903 d = kzalloc(sizeof(*d), GFP_KERNEL);
904 if (!d) {
905 ret = -ENOMEM;
906 goto err_alloc;
907 }
908
909 spin_lock_init(&d->lock);
910 INIT_LIST_HEAD(&d->chan_pending);
911
912 d->base = ioremap(res->start, resource_size(res));
913 if (!d->base) {
914 ret = -ENOMEM;
915 goto err_ioremap;
916 }
917
918 tasklet_init(&d->task, sa11x0_dma_tasklet, (unsigned long)d);
919
920 for (i = 0; i < NR_PHY_CHAN; i++) {
921 struct sa11x0_dma_phy *p = &d->phy[i];
922
923 p->dev = d;
924 p->num = i;
925 p->base = d->base + i * DMA_SIZE;
926 writel_relaxed(DCSR_RUN | DCSR_IE | DCSR_ERROR |
927 DCSR_DONEA | DCSR_STRTA | DCSR_DONEB | DCSR_STRTB,
928 p->base + DMA_DCSR_C);
929 writel_relaxed(0, p->base + DMA_DDAR);
930
931 ret = sa11x0_dma_request_irq(pdev, i, p);
932 if (ret) {
933 while (i) {
934 i--;
935 sa11x0_dma_free_irq(pdev, i, &d->phy[i]);
936 }
937 goto err_irq;
938 }
939 }
940
941 dma_cap_set(DMA_SLAVE, d->slave.cap_mask);
942 dma_cap_set(DMA_CYCLIC, d->slave.cap_mask);
943 d->slave.device_prep_slave_sg = sa11x0_dma_prep_slave_sg;
944 d->slave.device_prep_dma_cyclic = sa11x0_dma_prep_dma_cyclic;
945 d->slave.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
946 d->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
947 d->slave.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
948 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES);
949 d->slave.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
950 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES);
951 ret = sa11x0_dma_init_dmadev(&d->slave, &pdev->dev);
952 if (ret) {
953 dev_warn(d->slave.dev, "failed to register slave async device: %d\n",
954 ret);
955 goto err_slave_reg;
956 }
957
958 platform_set_drvdata(pdev, d);
959 return 0;
960
961 err_slave_reg:
962 sa11x0_dma_free_channels(&d->slave);
963 for (i = 0; i < NR_PHY_CHAN; i++)
964 sa11x0_dma_free_irq(pdev, i, &d->phy[i]);
965 err_irq:
966 tasklet_kill(&d->task);
967 iounmap(d->base);
968 err_ioremap:
969 kfree(d);
970 err_alloc:
971 return ret;
972 }
973
974 static int sa11x0_dma_remove(struct platform_device *pdev)
975 {
976 struct sa11x0_dma_dev *d = platform_get_drvdata(pdev);
977 unsigned pch;
978
979 dma_async_device_unregister(&d->slave);
980
981 sa11x0_dma_free_channels(&d->slave);
982 for (pch = 0; pch < NR_PHY_CHAN; pch++)
983 sa11x0_dma_free_irq(pdev, pch, &d->phy[pch]);
984 tasklet_kill(&d->task);
985 iounmap(d->base);
986 kfree(d);
987
988 return 0;
989 }
990
991 static int sa11x0_dma_suspend(struct device *dev)
992 {
993 struct sa11x0_dma_dev *d = dev_get_drvdata(dev);
994 unsigned pch;
995
996 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
997 struct sa11x0_dma_phy *p = &d->phy[pch];
998 u32 dcsr, saved_dcsr;
999
1000 dcsr = saved_dcsr = readl_relaxed(p->base + DMA_DCSR_R);
1001 if (dcsr & DCSR_RUN) {
1002 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C);
1003 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
1004 }
1005
1006 saved_dcsr &= DCSR_RUN | DCSR_IE;
1007 if (dcsr & DCSR_BIU) {
1008 p->dbs[0] = readl_relaxed(p->base + DMA_DBSB);
1009 p->dbt[0] = readl_relaxed(p->base + DMA_DBTB);
1010 p->dbs[1] = readl_relaxed(p->base + DMA_DBSA);
1011 p->dbt[1] = readl_relaxed(p->base + DMA_DBTA);
1012 saved_dcsr |= (dcsr & DCSR_STRTA ? DCSR_STRTB : 0) |
1013 (dcsr & DCSR_STRTB ? DCSR_STRTA : 0);
1014 } else {
1015 p->dbs[0] = readl_relaxed(p->base + DMA_DBSA);
1016 p->dbt[0] = readl_relaxed(p->base + DMA_DBTA);
1017 p->dbs[1] = readl_relaxed(p->base + DMA_DBSB);
1018 p->dbt[1] = readl_relaxed(p->base + DMA_DBTB);
1019 saved_dcsr |= dcsr & (DCSR_STRTA | DCSR_STRTB);
1020 }
1021 p->dcsr = saved_dcsr;
1022
1023 writel(DCSR_STRTA | DCSR_STRTB, p->base + DMA_DCSR_C);
1024 }
1025
1026 return 0;
1027 }
1028
1029 static int sa11x0_dma_resume(struct device *dev)
1030 {
1031 struct sa11x0_dma_dev *d = dev_get_drvdata(dev);
1032 unsigned pch;
1033
1034 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
1035 struct sa11x0_dma_phy *p = &d->phy[pch];
1036 struct sa11x0_dma_desc *txd = NULL;
1037 u32 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
1038
1039 WARN_ON(dcsr & (DCSR_BIU | DCSR_STRTA | DCSR_STRTB | DCSR_RUN));
1040
1041 if (p->txd_done)
1042 txd = p->txd_done;
1043 else if (p->txd_load)
1044 txd = p->txd_load;
1045
1046 if (!txd)
1047 continue;
1048
1049 writel_relaxed(txd->ddar, p->base + DMA_DDAR);
1050
1051 writel_relaxed(p->dbs[0], p->base + DMA_DBSA);
1052 writel_relaxed(p->dbt[0], p->base + DMA_DBTA);
1053 writel_relaxed(p->dbs[1], p->base + DMA_DBSB);
1054 writel_relaxed(p->dbt[1], p->base + DMA_DBTB);
1055 writel_relaxed(p->dcsr, p->base + DMA_DCSR_S);
1056 }
1057
1058 return 0;
1059 }
1060
1061 static const struct dev_pm_ops sa11x0_dma_pm_ops = {
1062 .suspend_noirq = sa11x0_dma_suspend,
1063 .resume_noirq = sa11x0_dma_resume,
1064 .freeze_noirq = sa11x0_dma_suspend,
1065 .thaw_noirq = sa11x0_dma_resume,
1066 .poweroff_noirq = sa11x0_dma_suspend,
1067 .restore_noirq = sa11x0_dma_resume,
1068 };
1069
1070 static struct platform_driver sa11x0_dma_driver = {
1071 .driver = {
1072 .name = "sa11x0-dma",
1073 .pm = &sa11x0_dma_pm_ops,
1074 },
1075 .probe = sa11x0_dma_probe,
1076 .remove = sa11x0_dma_remove,
1077 };
1078
1079 bool sa11x0_dma_filter_fn(struct dma_chan *chan, void *param)
1080 {
1081 if (chan->device->dev->driver == &sa11x0_dma_driver.driver) {
1082 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
1083 const char *p = param;
1084
1085 return !strcmp(c->name, p);
1086 }
1087 return false;
1088 }
1089 EXPORT_SYMBOL(sa11x0_dma_filter_fn);
1090
1091 static int __init sa11x0_dma_init(void)
1092 {
1093 return platform_driver_register(&sa11x0_dma_driver);
1094 }
1095 subsys_initcall(sa11x0_dma_init);
1096
1097 static void __exit sa11x0_dma_exit(void)
1098 {
1099 platform_driver_unregister(&sa11x0_dma_driver);
1100 }
1101 module_exit(sa11x0_dma_exit);
1102
1103 MODULE_AUTHOR("Russell King");
1104 MODULE_DESCRIPTION("SA-11x0 DMA driver");
1105 MODULE_LICENSE("GPL v2");
1106 MODULE_ALIAS("platform:sa11x0-dma");
Linux kernel - Deliverables
This page took 0.081383 seconds and 5 git commands to generate.