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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
[linux/fpc-iii.git] / drivers / dma / sa11x0-dma.c
blobab26d46bbe1598434625979abeb488d5199992d9
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 #ifdef CONFIG_PM_SLEEP
117 u32 dbs[2];
118 u32 dbt[2];
119 u32 dcsr;
120 #endif
121 };
122
123 struct sa11x0_dma_dev {
124 struct dma_device slave;
125 void __iomem *base;
126 spinlock_t lock;
127 struct tasklet_struct task;
128 struct list_head chan_pending;
129 struct sa11x0_dma_phy phy[NR_PHY_CHAN];
130 };
131
132 static struct sa11x0_dma_chan *to_sa11x0_dma_chan(struct dma_chan *chan)
133 {
134 return container_of(chan, struct sa11x0_dma_chan, vc.chan);
135 }
136
137 static struct sa11x0_dma_dev *to_sa11x0_dma(struct dma_device *dmadev)
138 {
139 return container_of(dmadev, struct sa11x0_dma_dev, slave);
140 }
141
142 static struct sa11x0_dma_desc *sa11x0_dma_next_desc(struct sa11x0_dma_chan *c)
143 {
144 struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
145
146 return vd ? container_of(vd, struct sa11x0_dma_desc, vd) : NULL;
147 }
148
149 static void sa11x0_dma_free_desc(struct virt_dma_desc *vd)
150 {
151 kfree(container_of(vd, struct sa11x0_dma_desc, vd));
152 }
153
154 static void sa11x0_dma_start_desc(struct sa11x0_dma_phy *p, struct sa11x0_dma_desc *txd)
155 {
156 list_del(&txd->vd.node);
157 p->txd_load = txd;
158 p->sg_load = 0;
159
160 dev_vdbg(p->dev->slave.dev, "pchan %u: txd %p[%x]: starting: DDAR:%x\n",
161 p->num, &txd->vd, txd->vd.tx.cookie, txd->ddar);
162 }
163
164 static void noinline sa11x0_dma_start_sg(struct sa11x0_dma_phy *p,
165 struct sa11x0_dma_chan *c)
166 {
167 struct sa11x0_dma_desc *txd = p->txd_load;
168 struct sa11x0_dma_sg *sg;
169 void __iomem *base = p->base;
170 unsigned dbsx, dbtx;
171 u32 dcsr;
172
173 if (!txd)
174 return;
175
176 dcsr = readl_relaxed(base + DMA_DCSR_R);
177
178 /* Don't try to load the next transfer if both buffers are started */
179 if ((dcsr & (DCSR_STRTA | DCSR_STRTB)) == (DCSR_STRTA | DCSR_STRTB))
180 return;
181
182 if (p->sg_load == txd->sglen) {
183 if (!txd->cyclic) {
184 struct sa11x0_dma_desc *txn = sa11x0_dma_next_desc(c);
185
186 /*
187 * We have reached the end of the current descriptor.
188 * Peek at the next descriptor, and if compatible with
189 * the current, start processing it.
190 */
191 if (txn && txn->ddar == txd->ddar) {
192 txd = txn;
193 sa11x0_dma_start_desc(p, txn);
194 } else {
195 p->txd_load = NULL;
196 return;
197 }
198 } else {
199 /* Cyclic: reset back to beginning */
200 p->sg_load = 0;
201 }
202 }
203
204 sg = &txd->sg[p->sg_load++];
205
206 /* Select buffer to load according to channel status */
207 if (((dcsr & (DCSR_BIU | DCSR_STRTB)) == (DCSR_BIU | DCSR_STRTB)) ||
208 ((dcsr & (DCSR_BIU | DCSR_STRTA)) == 0)) {
209 dbsx = DMA_DBSA;
210 dbtx = DMA_DBTA;
211 dcsr = DCSR_STRTA | DCSR_IE | DCSR_RUN;
212 } else {
213 dbsx = DMA_DBSB;
214 dbtx = DMA_DBTB;
215 dcsr = DCSR_STRTB | DCSR_IE | DCSR_RUN;
216 }
217
218 writel_relaxed(sg->addr, base + dbsx);
219 writel_relaxed(sg->len, base + dbtx);
220 writel(dcsr, base + DMA_DCSR_S);
221
222 dev_dbg(p->dev->slave.dev, "pchan %u: load: DCSR:%02x DBS%c:%08x DBT%c:%08x\n",
223 p->num, dcsr,
224 'A' + (dbsx == DMA_DBSB), sg->addr,
225 'A' + (dbtx == DMA_DBTB), sg->len);
226 }
227
228 static void noinline sa11x0_dma_complete(struct sa11x0_dma_phy *p,
229 struct sa11x0_dma_chan *c)
230 {
231 struct sa11x0_dma_desc *txd = p->txd_done;
232
233 if (++p->sg_done == txd->sglen) {
234 if (!txd->cyclic) {
235 vchan_cookie_complete(&txd->vd);
236
237 p->sg_done = 0;
238 p->txd_done = p->txd_load;
239
240 if (!p->txd_done)
241 tasklet_schedule(&p->dev->task);
242 } else {
243 if ((p->sg_done % txd->period) == 0)
244 vchan_cyclic_callback(&txd->vd);
245
246 /* Cyclic: reset back to beginning */
247 p->sg_done = 0;
248 }
249 }
250
251 sa11x0_dma_start_sg(p, c);
252 }
253
254 static irqreturn_t sa11x0_dma_irq(int irq, void *dev_id)
255 {
256 struct sa11x0_dma_phy *p = dev_id;
257 struct sa11x0_dma_dev *d = p->dev;
258 struct sa11x0_dma_chan *c;
259 u32 dcsr;
260
261 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
262 if (!(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB)))
263 return IRQ_NONE;
264
265 /* Clear reported status bits */
266 writel_relaxed(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB),
267 p->base + DMA_DCSR_C);
268
269 dev_dbg(d->slave.dev, "pchan %u: irq: DCSR:%02x\n", p->num, dcsr);
270
271 if (dcsr & DCSR_ERROR) {
272 dev_err(d->slave.dev, "pchan %u: error. DCSR:%02x DDAR:%08x DBSA:%08x DBTA:%08x DBSB:%08x DBTB:%08x\n",
273 p->num, dcsr,
274 readl_relaxed(p->base + DMA_DDAR),
275 readl_relaxed(p->base + DMA_DBSA),
276 readl_relaxed(p->base + DMA_DBTA),
277 readl_relaxed(p->base + DMA_DBSB),
278 readl_relaxed(p->base + DMA_DBTB));
279 }
280
281 c = p->vchan;
282 if (c) {
283 unsigned long flags;
284
285 spin_lock_irqsave(&c->vc.lock, flags);
286 /*
287 * Now that we're holding the lock, check that the vchan
288 * really is associated with this pchan before touching the
289 * hardware. This should always succeed, because we won't
290 * change p->vchan or c->phy while the channel is actively
291 * transferring.
292 */
293 if (c->phy == p) {
294 if (dcsr & DCSR_DONEA)
295 sa11x0_dma_complete(p, c);
296 if (dcsr & DCSR_DONEB)
297 sa11x0_dma_complete(p, c);
298 }
299 spin_unlock_irqrestore(&c->vc.lock, flags);
300 }
301
302 return IRQ_HANDLED;
303 }
304
305 static void sa11x0_dma_start_txd(struct sa11x0_dma_chan *c)
306 {
307 struct sa11x0_dma_desc *txd = sa11x0_dma_next_desc(c);
308
309 /* If the issued list is empty, we have no further txds to process */
310 if (txd) {
311 struct sa11x0_dma_phy *p = c->phy;
312
313 sa11x0_dma_start_desc(p, txd);
314 p->txd_done = txd;
315 p->sg_done = 0;
316
317 /* The channel should not have any transfers started */
318 WARN_ON(readl_relaxed(p->base + DMA_DCSR_R) &
319 (DCSR_STRTA | DCSR_STRTB));
320
321 /* Clear the run and start bits before changing DDAR */
322 writel_relaxed(DCSR_RUN | DCSR_STRTA | DCSR_STRTB,
323 p->base + DMA_DCSR_C);
324 writel_relaxed(txd->ddar, p->base + DMA_DDAR);
325
326 /* Try to start both buffers */
327 sa11x0_dma_start_sg(p, c);
328 sa11x0_dma_start_sg(p, c);
329 }
330 }
331
332 static void sa11x0_dma_tasklet(unsigned long arg)
333 {
334 struct sa11x0_dma_dev *d = (struct sa11x0_dma_dev *)arg;
335 struct sa11x0_dma_phy *p;
336 struct sa11x0_dma_chan *c;
337 unsigned pch, pch_alloc = 0;
338
339 dev_dbg(d->slave.dev, "tasklet enter\n");
340
341 list_for_each_entry(c, &d->slave.channels, vc.chan.device_node) {
342 spin_lock_irq(&c->vc.lock);
343 p = c->phy;
344 if (p && !p->txd_done) {
345 sa11x0_dma_start_txd(c);
346 if (!p->txd_done) {
347 /* No current txd associated with this channel */
348 dev_dbg(d->slave.dev, "pchan %u: free\n", p->num);
349
350 /* Mark this channel free */
351 c->phy = NULL;
352 p->vchan = NULL;
353 }
354 }
355 spin_unlock_irq(&c->vc.lock);
356 }
357
358 spin_lock_irq(&d->lock);
359 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
360 p = &d->phy[pch];
361
362 if (p->vchan == NULL && !list_empty(&d->chan_pending)) {
363 c = list_first_entry(&d->chan_pending,
364 struct sa11x0_dma_chan, node);
365 list_del_init(&c->node);
366
367 pch_alloc |= 1 << pch;
368
369 /* Mark this channel allocated */
370 p->vchan = c;
371
372 dev_dbg(d->slave.dev, "pchan %u: alloc vchan %p\n", pch, &c->vc);
373 }
374 }
375 spin_unlock_irq(&d->lock);
376
377 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
378 if (pch_alloc & (1 << pch)) {
379 p = &d->phy[pch];
380 c = p->vchan;
381
382 spin_lock_irq(&c->vc.lock);
383 c->phy = p;
384
385 sa11x0_dma_start_txd(c);
386 spin_unlock_irq(&c->vc.lock);
387 }
388 }
389
390 dev_dbg(d->slave.dev, "tasklet exit\n");
391 }
392
393
394 static int sa11x0_dma_alloc_chan_resources(struct dma_chan *chan)
395 {
396 return 0;
397 }
398
399 static void sa11x0_dma_free_chan_resources(struct dma_chan *chan)
400 {
401 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
402 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
403 unsigned long flags;
404
405 spin_lock_irqsave(&d->lock, flags);
406 list_del_init(&c->node);
407 spin_unlock_irqrestore(&d->lock, flags);
408
409 vchan_free_chan_resources(&c->vc);
410 }
411
412 static dma_addr_t sa11x0_dma_pos(struct sa11x0_dma_phy *p)
413 {
414 unsigned reg;
415 u32 dcsr;
416
417 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
418
419 if ((dcsr & (DCSR_BIU | DCSR_STRTA)) == DCSR_STRTA ||
420 (dcsr & (DCSR_BIU | DCSR_STRTB)) == DCSR_BIU)
421 reg = DMA_DBSA;
422 else
423 reg = DMA_DBSB;
424
425 return readl_relaxed(p->base + reg);
426 }
427
428 static enum dma_status sa11x0_dma_tx_status(struct dma_chan *chan,
429 dma_cookie_t cookie, struct dma_tx_state *state)
430 {
431 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
432 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
433 struct sa11x0_dma_phy *p;
434 struct virt_dma_desc *vd;
435 unsigned long flags;
436 enum dma_status ret;
437
438 ret = dma_cookie_status(&c->vc.chan, cookie, state);
439 if (ret == DMA_COMPLETE)
440 return ret;
441
442 if (!state)
443 return c->status;
444
445 spin_lock_irqsave(&c->vc.lock, flags);
446 p = c->phy;
447
448 /*
449 * If the cookie is on our issue queue, then the residue is
450 * its total size.
451 */
452 vd = vchan_find_desc(&c->vc, cookie);
453 if (vd) {
454 state->residue = container_of(vd, struct sa11x0_dma_desc, vd)->size;
455 } else if (!p) {
456 state->residue = 0;
457 } else {
458 struct sa11x0_dma_desc *txd;
459 size_t bytes = 0;
460
461 if (p->txd_done && p->txd_done->vd.tx.cookie == cookie)
462 txd = p->txd_done;
463 else if (p->txd_load && p->txd_load->vd.tx.cookie == cookie)
464 txd = p->txd_load;
465 else
466 txd = NULL;
467
468 ret = c->status;
469 if (txd) {
470 dma_addr_t addr = sa11x0_dma_pos(p);
471 unsigned i;
472
473 dev_vdbg(d->slave.dev, "tx_status: addr:%x\n", addr);
474
475 for (i = 0; i < txd->sglen; i++) {
476 dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x\n",
477 i, txd->sg[i].addr, txd->sg[i].len);
478 if (addr >= txd->sg[i].addr &&
479 addr < txd->sg[i].addr + txd->sg[i].len) {
480 unsigned len;
481
482 len = txd->sg[i].len -
483 (addr - txd->sg[i].addr);
484 dev_vdbg(d->slave.dev, "tx_status: [%u] +%x\n",
485 i, len);
486 bytes += len;
487 i++;
488 break;
489 }
490 }
491 for (; i < txd->sglen; i++) {
492 dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x ++\n",
493 i, txd->sg[i].addr, txd->sg[i].len);
494 bytes += txd->sg[i].len;
495 }
496 }
497 state->residue = bytes;
498 }
499 spin_unlock_irqrestore(&c->vc.lock, flags);
500
501 dev_vdbg(d->slave.dev, "tx_status: bytes 0x%zx\n", state->residue);
502
503 return ret;
504 }
505
506 /*
507 * Move pending txds to the issued list, and re-init pending list.
508 * If not already pending, add this channel to the list of pending
509 * channels and trigger the tasklet to run.
510 */
511 static void sa11x0_dma_issue_pending(struct dma_chan *chan)
512 {
513 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
514 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
515 unsigned long flags;
516
517 spin_lock_irqsave(&c->vc.lock, flags);
518 if (vchan_issue_pending(&c->vc)) {
519 if (!c->phy) {
520 spin_lock(&d->lock);
521 if (list_empty(&c->node)) {
522 list_add_tail(&c->node, &d->chan_pending);
523 tasklet_schedule(&d->task);
524 dev_dbg(d->slave.dev, "vchan %p: issued\n", &c->vc);
525 }
526 spin_unlock(&d->lock);
527 }
528 } else
529 dev_dbg(d->slave.dev, "vchan %p: nothing to issue\n", &c->vc);
530 spin_unlock_irqrestore(&c->vc.lock, flags);
531 }
532
533 static struct dma_async_tx_descriptor *sa11x0_dma_prep_slave_sg(
534 struct dma_chan *chan, struct scatterlist *sg, unsigned int sglen,
535 enum dma_transfer_direction dir, unsigned long flags, void *context)
536 {
537 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
538 struct sa11x0_dma_desc *txd;
539 struct scatterlist *sgent;
540 unsigned i, j = sglen;
541 size_t size = 0;
542
543 /* SA11x0 channels can only operate in their native direction */
544 if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) {
545 dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n",
546 &c->vc, c->ddar, dir);
547 return NULL;
548 }
549
550 /* Do not allow zero-sized txds */
551 if (sglen == 0)
552 return NULL;
553
554 for_each_sg(sg, sgent, sglen, i) {
555 dma_addr_t addr = sg_dma_address(sgent);
556 unsigned int len = sg_dma_len(sgent);
557
558 if (len > DMA_MAX_SIZE)
559 j += DIV_ROUND_UP(len, DMA_MAX_SIZE & ~DMA_ALIGN) - 1;
560 if (addr & DMA_ALIGN) {
561 dev_dbg(chan->device->dev, "vchan %p: bad buffer alignment: %08x\n",
562 &c->vc, addr);
563 return NULL;
564 }
565 }
566
567 txd = kzalloc(sizeof(*txd) + j * sizeof(txd->sg[0]), GFP_ATOMIC);
568 if (!txd) {
569 dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc);
570 return NULL;
571 }
572
573 j = 0;
574 for_each_sg(sg, sgent, sglen, i) {
575 dma_addr_t addr = sg_dma_address(sgent);
576 unsigned len = sg_dma_len(sgent);
577
578 size += len;
579
580 do {
581 unsigned tlen = len;
582
583 /*
584 * Check whether the transfer will fit. If not, try
585 * to split the transfer up such that we end up with
586 * equal chunks - but make sure that we preserve the
587 * alignment. This avoids small segments.
588 */
589 if (tlen > DMA_MAX_SIZE) {
590 unsigned mult = DIV_ROUND_UP(tlen,
591 DMA_MAX_SIZE & ~DMA_ALIGN);
592
593 tlen = (tlen / mult) & ~DMA_ALIGN;
594 }
595
596 txd->sg[j].addr = addr;
597 txd->sg[j].len = tlen;
598
599 addr += tlen;
600 len -= tlen;
601 j++;
602 } while (len);
603 }
604
605 txd->ddar = c->ddar;
606 txd->size = size;
607 txd->sglen = j;
608
609 dev_dbg(chan->device->dev, "vchan %p: txd %p: size %u nr %u\n",
610 &c->vc, &txd->vd, txd->size, txd->sglen);
611
612 return vchan_tx_prep(&c->vc, &txd->vd, flags);
613 }
614
615 static struct dma_async_tx_descriptor *sa11x0_dma_prep_dma_cyclic(
616 struct dma_chan *chan, dma_addr_t addr, size_t size, size_t period,
617 enum dma_transfer_direction dir, unsigned long flags, void *context)
618 {
619 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
620 struct sa11x0_dma_desc *txd;
621 unsigned i, j, k, sglen, sgperiod;
622
623 /* SA11x0 channels can only operate in their native direction */
624 if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) {
625 dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n",
626 &c->vc, c->ddar, dir);
627 return NULL;
628 }
629
630 sgperiod = DIV_ROUND_UP(period, DMA_MAX_SIZE & ~DMA_ALIGN);
631 sglen = size * sgperiod / period;
632
633 /* Do not allow zero-sized txds */
634 if (sglen == 0)
635 return NULL;
636
637 txd = kzalloc(sizeof(*txd) + sglen * sizeof(txd->sg[0]), GFP_ATOMIC);
638 if (!txd) {
639 dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc);
640 return NULL;
641 }
642
643 for (i = k = 0; i < size / period; i++) {
644 size_t tlen, len = period;
645
646 for (j = 0; j < sgperiod; j++, k++) {
647 tlen = len;
648
649 if (tlen > DMA_MAX_SIZE) {
650 unsigned mult = DIV_ROUND_UP(tlen, DMA_MAX_SIZE & ~DMA_ALIGN);
651 tlen = (tlen / mult) & ~DMA_ALIGN;
652 }
653
654 txd->sg[k].addr = addr;
655 txd->sg[k].len = tlen;
656 addr += tlen;
657 len -= tlen;
658 }
659
660 WARN_ON(len != 0);
661 }
662
663 WARN_ON(k != sglen);
664
665 txd->ddar = c->ddar;
666 txd->size = size;
667 txd->sglen = sglen;
668 txd->cyclic = 1;
669 txd->period = sgperiod;
670
671 return vchan_tx_prep(&c->vc, &txd->vd, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
672 }
673
674 static int sa11x0_dma_slave_config(struct sa11x0_dma_chan *c, struct dma_slave_config *cfg)
675 {
676 u32 ddar = c->ddar & ((0xf << 4) | DDAR_RW);
677 dma_addr_t addr;
678 enum dma_slave_buswidth width;
679 u32 maxburst;
680
681 if (ddar & DDAR_RW) {
682 addr = cfg->src_addr;
683 width = cfg->src_addr_width;
684 maxburst = cfg->src_maxburst;
685 } else {
686 addr = cfg->dst_addr;
687 width = cfg->dst_addr_width;
688 maxburst = cfg->dst_maxburst;
689 }
690
691 if ((width != DMA_SLAVE_BUSWIDTH_1_BYTE &&
692 width != DMA_SLAVE_BUSWIDTH_2_BYTES) ||
693 (maxburst != 4 && maxburst != 8))
694 return -EINVAL;
695
696 if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
697 ddar |= DDAR_DW;
698 if (maxburst == 8)
699 ddar |= DDAR_BS;
700
701 dev_dbg(c->vc.chan.device->dev, "vchan %p: dma_slave_config addr %x width %u burst %u\n",
702 &c->vc, addr, width, maxburst);
703
704 c->ddar = ddar | (addr & 0xf0000000) | (addr & 0x003ffffc) << 6;
705
706 return 0;
707 }
708
709 static int sa11x0_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
710 unsigned long arg)
711 {
712 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
713 struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device);
714 struct sa11x0_dma_phy *p;
715 LIST_HEAD(head);
716 unsigned long flags;
717 int ret;
718
719 switch (cmd) {
720 case DMA_SLAVE_CONFIG:
721 return sa11x0_dma_slave_config(c, (struct dma_slave_config *)arg);
722
723 case DMA_TERMINATE_ALL:
724 dev_dbg(d->slave.dev, "vchan %p: terminate all\n", &c->vc);
725 /* Clear the tx descriptor lists */
726 spin_lock_irqsave(&c->vc.lock, flags);
727 vchan_get_all_descriptors(&c->vc, &head);
728
729 p = c->phy;
730 if (p) {
731 dev_dbg(d->slave.dev, "pchan %u: terminating\n", p->num);
732 /* vchan is assigned to a pchan - stop the channel */
733 writel(DCSR_RUN | DCSR_IE |
734 DCSR_STRTA | DCSR_DONEA |
735 DCSR_STRTB | DCSR_DONEB,
736 p->base + DMA_DCSR_C);
737
738 if (p->txd_load) {
739 if (p->txd_load != p->txd_done)
740 list_add_tail(&p->txd_load->vd.node, &head);
741 p->txd_load = NULL;
742 }
743 if (p->txd_done) {
744 list_add_tail(&p->txd_done->vd.node, &head);
745 p->txd_done = NULL;
746 }
747 c->phy = NULL;
748 spin_lock(&d->lock);
749 p->vchan = NULL;
750 spin_unlock(&d->lock);
751 tasklet_schedule(&d->task);
752 }
753 spin_unlock_irqrestore(&c->vc.lock, flags);
754 vchan_dma_desc_free_list(&c->vc, &head);
755 ret = 0;
756 break;
757
758 case DMA_PAUSE:
759 dev_dbg(d->slave.dev, "vchan %p: pause\n", &c->vc);
760 spin_lock_irqsave(&c->vc.lock, flags);
761 if (c->status == DMA_IN_PROGRESS) {
762 c->status = DMA_PAUSED;
763
764 p = c->phy;
765 if (p) {
766 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C);
767 } else {
768 spin_lock(&d->lock);
769 list_del_init(&c->node);
770 spin_unlock(&d->lock);
771 }
772 }
773 spin_unlock_irqrestore(&c->vc.lock, flags);
774 ret = 0;
775 break;
776
777 case DMA_RESUME:
778 dev_dbg(d->slave.dev, "vchan %p: resume\n", &c->vc);
779 spin_lock_irqsave(&c->vc.lock, flags);
780 if (c->status == DMA_PAUSED) {
781 c->status = DMA_IN_PROGRESS;
782
783 p = c->phy;
784 if (p) {
785 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_S);
786 } else if (!list_empty(&c->vc.desc_issued)) {
787 spin_lock(&d->lock);
788 list_add_tail(&c->node, &d->chan_pending);
789 spin_unlock(&d->lock);
790 }
791 }
792 spin_unlock_irqrestore(&c->vc.lock, flags);
793 ret = 0;
794 break;
795
796 default:
797 ret = -ENXIO;
798 break;
799 }
800
801 return ret;
802 }
803
804 struct sa11x0_dma_channel_desc {
805 u32 ddar;
806 const char *name;
807 };
808
809 #define CD(d1, d2) { .ddar = DDAR_##d1 | d2, .name = #d1 }
810 static const struct sa11x0_dma_channel_desc chan_desc[] = {
811 CD(Ser0UDCTr, 0),
812 CD(Ser0UDCRc, DDAR_RW),
813 CD(Ser1SDLCTr, 0),
814 CD(Ser1SDLCRc, DDAR_RW),
815 CD(Ser1UARTTr, 0),
816 CD(Ser1UARTRc, DDAR_RW),
817 CD(Ser2ICPTr, 0),
818 CD(Ser2ICPRc, DDAR_RW),
819 CD(Ser3UARTTr, 0),
820 CD(Ser3UARTRc, DDAR_RW),
821 CD(Ser4MCP0Tr, 0),
822 CD(Ser4MCP0Rc, DDAR_RW),
823 CD(Ser4MCP1Tr, 0),
824 CD(Ser4MCP1Rc, DDAR_RW),
825 CD(Ser4SSPTr, 0),
826 CD(Ser4SSPRc, DDAR_RW),
827 };
828
829 static int sa11x0_dma_init_dmadev(struct dma_device *dmadev,
830 struct device *dev)
831 {
832 unsigned i;
833
834 dmadev->chancnt = ARRAY_SIZE(chan_desc);
835 INIT_LIST_HEAD(&dmadev->channels);
836 dmadev->dev = dev;
837 dmadev->device_alloc_chan_resources = sa11x0_dma_alloc_chan_resources;
838 dmadev->device_free_chan_resources = sa11x0_dma_free_chan_resources;
839 dmadev->device_control = sa11x0_dma_control;
840 dmadev->device_tx_status = sa11x0_dma_tx_status;
841 dmadev->device_issue_pending = sa11x0_dma_issue_pending;
842
843 for (i = 0; i < dmadev->chancnt; i++) {
844 struct sa11x0_dma_chan *c;
845
846 c = kzalloc(sizeof(*c), GFP_KERNEL);
847 if (!c) {
848 dev_err(dev, "no memory for channel %u\n", i);
849 return -ENOMEM;
850 }
851
852 c->status = DMA_IN_PROGRESS;
853 c->ddar = chan_desc[i].ddar;
854 c->name = chan_desc[i].name;
855 INIT_LIST_HEAD(&c->node);
856
857 c->vc.desc_free = sa11x0_dma_free_desc;
858 vchan_init(&c->vc, dmadev);
859 }
860
861 return dma_async_device_register(dmadev);
862 }
863
864 static int sa11x0_dma_request_irq(struct platform_device *pdev, int nr,
865 void *data)
866 {
867 int irq = platform_get_irq(pdev, nr);
868
869 if (irq <= 0)
870 return -ENXIO;
871
872 return request_irq(irq, sa11x0_dma_irq, 0, dev_name(&pdev->dev), data);
873 }
874
875 static void sa11x0_dma_free_irq(struct platform_device *pdev, int nr,
876 void *data)
877 {
878 int irq = platform_get_irq(pdev, nr);
879 if (irq > 0)
880 free_irq(irq, data);
881 }
882
883 static void sa11x0_dma_free_channels(struct dma_device *dmadev)
884 {
885 struct sa11x0_dma_chan *c, *cn;
886
887 list_for_each_entry_safe(c, cn, &dmadev->channels, vc.chan.device_node) {
888 list_del(&c->vc.chan.device_node);
889 tasklet_kill(&c->vc.task);
890 kfree(c);
891 }
892 }
893
894 static int sa11x0_dma_probe(struct platform_device *pdev)
895 {
896 struct sa11x0_dma_dev *d;
897 struct resource *res;
898 unsigned i;
899 int ret;
900
901 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
902 if (!res)
903 return -ENXIO;
904
905 d = kzalloc(sizeof(*d), GFP_KERNEL);
906 if (!d) {
907 ret = -ENOMEM;
908 goto err_alloc;
909 }
910
911 spin_lock_init(&d->lock);
912 INIT_LIST_HEAD(&d->chan_pending);
913
914 d->base = ioremap(res->start, resource_size(res));
915 if (!d->base) {
916 ret = -ENOMEM;
917 goto err_ioremap;
918 }
919
920 tasklet_init(&d->task, sa11x0_dma_tasklet, (unsigned long)d);
921
922 for (i = 0; i < NR_PHY_CHAN; i++) {
923 struct sa11x0_dma_phy *p = &d->phy[i];
924
925 p->dev = d;
926 p->num = i;
927 p->base = d->base + i * DMA_SIZE;
928 writel_relaxed(DCSR_RUN | DCSR_IE | DCSR_ERROR |
929 DCSR_DONEA | DCSR_STRTA | DCSR_DONEB | DCSR_STRTB,
930 p->base + DMA_DCSR_C);
931 writel_relaxed(0, p->base + DMA_DDAR);
932
933 ret = sa11x0_dma_request_irq(pdev, i, p);
934 if (ret) {
935 while (i) {
936 i--;
937 sa11x0_dma_free_irq(pdev, i, &d->phy[i]);
938 }
939 goto err_irq;
940 }
941 }
942
943 dma_cap_set(DMA_SLAVE, d->slave.cap_mask);
944 dma_cap_set(DMA_CYCLIC, d->slave.cap_mask);
945 d->slave.device_prep_slave_sg = sa11x0_dma_prep_slave_sg;
946 d->slave.device_prep_dma_cyclic = sa11x0_dma_prep_dma_cyclic;
947 ret = sa11x0_dma_init_dmadev(&d->slave, &pdev->dev);
948 if (ret) {
949 dev_warn(d->slave.dev, "failed to register slave async device: %d\n",
950 ret);
951 goto err_slave_reg;
952 }
953
954 platform_set_drvdata(pdev, d);
955 return 0;
956
957 err_slave_reg:
958 sa11x0_dma_free_channels(&d->slave);
959 for (i = 0; i < NR_PHY_CHAN; i++)
960 sa11x0_dma_free_irq(pdev, i, &d->phy[i]);
961 err_irq:
962 tasklet_kill(&d->task);
963 iounmap(d->base);
964 err_ioremap:
965 kfree(d);
966 err_alloc:
967 return ret;
968 }
969
970 static int sa11x0_dma_remove(struct platform_device *pdev)
971 {
972 struct sa11x0_dma_dev *d = platform_get_drvdata(pdev);
973 unsigned pch;
974
975 dma_async_device_unregister(&d->slave);
976
977 sa11x0_dma_free_channels(&d->slave);
978 for (pch = 0; pch < NR_PHY_CHAN; pch++)
979 sa11x0_dma_free_irq(pdev, pch, &d->phy[pch]);
980 tasklet_kill(&d->task);
981 iounmap(d->base);
982 kfree(d);
983
984 return 0;
985 }
986
987 #ifdef CONFIG_PM_SLEEP
988 static int sa11x0_dma_suspend(struct device *dev)
989 {
990 struct sa11x0_dma_dev *d = dev_get_drvdata(dev);
991 unsigned pch;
992
993 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
994 struct sa11x0_dma_phy *p = &d->phy[pch];
995 u32 dcsr, saved_dcsr;
996
997 dcsr = saved_dcsr = readl_relaxed(p->base + DMA_DCSR_R);
998 if (dcsr & DCSR_RUN) {
999 writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C);
1000 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
1001 }
1002
1003 saved_dcsr &= DCSR_RUN | DCSR_IE;
1004 if (dcsr & DCSR_BIU) {
1005 p->dbs[0] = readl_relaxed(p->base + DMA_DBSB);
1006 p->dbt[0] = readl_relaxed(p->base + DMA_DBTB);
1007 p->dbs[1] = readl_relaxed(p->base + DMA_DBSA);
1008 p->dbt[1] = readl_relaxed(p->base + DMA_DBTA);
1009 saved_dcsr |= (dcsr & DCSR_STRTA ? DCSR_STRTB : 0) |
1010 (dcsr & DCSR_STRTB ? DCSR_STRTA : 0);
1011 } else {
1012 p->dbs[0] = readl_relaxed(p->base + DMA_DBSA);
1013 p->dbt[0] = readl_relaxed(p->base + DMA_DBTA);
1014 p->dbs[1] = readl_relaxed(p->base + DMA_DBSB);
1015 p->dbt[1] = readl_relaxed(p->base + DMA_DBTB);
1016 saved_dcsr |= dcsr & (DCSR_STRTA | DCSR_STRTB);
1017 }
1018 p->dcsr = saved_dcsr;
1019
1020 writel(DCSR_STRTA | DCSR_STRTB, p->base + DMA_DCSR_C);
1021 }
1022
1023 return 0;
1024 }
1025
1026 static int sa11x0_dma_resume(struct device *dev)
1027 {
1028 struct sa11x0_dma_dev *d = dev_get_drvdata(dev);
1029 unsigned pch;
1030
1031 for (pch = 0; pch < NR_PHY_CHAN; pch++) {
1032 struct sa11x0_dma_phy *p = &d->phy[pch];
1033 struct sa11x0_dma_desc *txd = NULL;
1034 u32 dcsr = readl_relaxed(p->base + DMA_DCSR_R);
1035
1036 WARN_ON(dcsr & (DCSR_BIU | DCSR_STRTA | DCSR_STRTB | DCSR_RUN));
1037
1038 if (p->txd_done)
1039 txd = p->txd_done;
1040 else if (p->txd_load)
1041 txd = p->txd_load;
1042
1043 if (!txd)
1044 continue;
1045
1046 writel_relaxed(txd->ddar, p->base + DMA_DDAR);
1047
1048 writel_relaxed(p->dbs[0], p->base + DMA_DBSA);
1049 writel_relaxed(p->dbt[0], p->base + DMA_DBTA);
1050 writel_relaxed(p->dbs[1], p->base + DMA_DBSB);
1051 writel_relaxed(p->dbt[1], p->base + DMA_DBTB);
1052 writel_relaxed(p->dcsr, p->base + DMA_DCSR_S);
1053 }
1054
1055 return 0;
1056 }
1057 #endif
1058
1059 static const struct dev_pm_ops sa11x0_dma_pm_ops = {
1060 .suspend_noirq = sa11x0_dma_suspend,
1061 .resume_noirq = sa11x0_dma_resume,
1062 .freeze_noirq = sa11x0_dma_suspend,
1063 .thaw_noirq = sa11x0_dma_resume,
1064 .poweroff_noirq = sa11x0_dma_suspend,
1065 .restore_noirq = sa11x0_dma_resume,
1066 };
1067
1068 static struct platform_driver sa11x0_dma_driver = {
1069 .driver = {
1070 .name = "sa11x0-dma",
1071 .owner = THIS_MODULE,
1072 .pm = &sa11x0_dma_pm_ops,
1073 },
1074 .probe = sa11x0_dma_probe,
1075 .remove = sa11x0_dma_remove,
1076 };
1077
1078 bool sa11x0_dma_filter_fn(struct dma_chan *chan, void *param)
1079 {
1080 if (chan->device->dev->driver == &sa11x0_dma_driver.driver) {
1081 struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
1082 const char *p = param;
1083
1084 return !strcmp(c->name, p);
1085 }
1086 return false;
1087 }
1088 EXPORT_SYMBOL(sa11x0_dma_filter_fn);
1089
1090 static int __init sa11x0_dma_init(void)
1091 {
1092 return platform_driver_register(&sa11x0_dma_driver);
1093 }
1094 subsys_initcall(sa11x0_dma_init);
1095
1096 static void __exit sa11x0_dma_exit(void)
1097 {
1098 platform_driver_unregister(&sa11x0_dma_driver);
1099 }
1100 module_exit(sa11x0_dma_exit);
1101
1102 MODULE_AUTHOR("Russell King");
1103 MODULE_DESCRIPTION("SA-11x0 DMA driver");
1104 MODULE_LICENSE("GPL v2");
1105 MODULE_ALIAS("platform:sa11x0-dma");
Linux with added FPC-III support