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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc
[linux-2.6.git] / drivers / dma / mpc512x_dma.c
blob4e9cbf3005947a519e8d69ee6126753d2feaf287
1 /*
2 * Copyright (C) Freescale Semicondutor, Inc. 2007, 2008.
3 * Copyright (C) Semihalf 2009
4 *
5 * Written by Piotr Ziecik <kosmo@semihalf.com>. Hardware description
6 * (defines, structures and comments) was taken from MPC5121 DMA driver
7 * written by Hongjun Chen <hong-jun.chen@freescale.com>.
8 *
9 * Approved as OSADL project by a majority of OSADL members and funded
10 * by OSADL membership fees in 2009; for details see www.osadl.org.
11 *
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the Free
14 * Software Foundation; either version 2 of the License, or (at your option)
15 * any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but WITHOUT
18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
20 * more details.
21 *
22 * You should have received a copy of the GNU General Public License along with
23 * this program; if not, write to the Free Software Foundation, Inc., 59
24 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 *
26 * The full GNU General Public License is included in this distribution in the
27 * file called COPYING.
28 */
29
30 /*
31 * This is initial version of MPC5121 DMA driver. Only memory to memory
32 * transfers are supported (tested using dmatest module).
33 */
34
35 #include <linux/module.h>
36 #include <linux/dmaengine.h>
37 #include <linux/dma-mapping.h>
38 #include <linux/interrupt.h>
39 #include <linux/io.h>
40 #include <linux/slab.h>
41 #include <linux/of_device.h>
42 #include <linux/of_platform.h>
43
44 #include <linux/random.h>
45
46 /* Number of DMA Transfer descriptors allocated per channel */
47 #define MPC_DMA_DESCRIPTORS 64
48
49 /* Macro definitions */
50 #define MPC_DMA_CHANNELS 64
51 #define MPC_DMA_TCD_OFFSET 0x1000
52
53 /* Arbitration mode of group and channel */
54 #define MPC_DMA_DMACR_EDCG (1 << 31)
55 #define MPC_DMA_DMACR_ERGA (1 << 3)
56 #define MPC_DMA_DMACR_ERCA (1 << 2)
57
58 /* Error codes */
59 #define MPC_DMA_DMAES_VLD (1 << 31)
60 #define MPC_DMA_DMAES_GPE (1 << 15)
61 #define MPC_DMA_DMAES_CPE (1 << 14)
62 #define MPC_DMA_DMAES_ERRCHN(err) \
63 (((err) >> 8) & 0x3f)
64 #define MPC_DMA_DMAES_SAE (1 << 7)
65 #define MPC_DMA_DMAES_SOE (1 << 6)
66 #define MPC_DMA_DMAES_DAE (1 << 5)
67 #define MPC_DMA_DMAES_DOE (1 << 4)
68 #define MPC_DMA_DMAES_NCE (1 << 3)
69 #define MPC_DMA_DMAES_SGE (1 << 2)
70 #define MPC_DMA_DMAES_SBE (1 << 1)
71 #define MPC_DMA_DMAES_DBE (1 << 0)
72
73 #define MPC_DMA_TSIZE_1 0x00
74 #define MPC_DMA_TSIZE_2 0x01
75 #define MPC_DMA_TSIZE_4 0x02
76 #define MPC_DMA_TSIZE_16 0x04
77 #define MPC_DMA_TSIZE_32 0x05
78
79 /* MPC5121 DMA engine registers */
80 struct __attribute__ ((__packed__)) mpc_dma_regs {
81 /* 0x00 */
82 u32 dmacr; /* DMA control register */
83 u32 dmaes; /* DMA error status */
84 /* 0x08 */
85 u32 dmaerqh; /* DMA enable request high(channels 63~32) */
86 u32 dmaerql; /* DMA enable request low(channels 31~0) */
87 u32 dmaeeih; /* DMA enable error interrupt high(ch63~32) */
88 u32 dmaeeil; /* DMA enable error interrupt low(ch31~0) */
89 /* 0x18 */
90 u8 dmaserq; /* DMA set enable request */
91 u8 dmacerq; /* DMA clear enable request */
92 u8 dmaseei; /* DMA set enable error interrupt */
93 u8 dmaceei; /* DMA clear enable error interrupt */
94 /* 0x1c */
95 u8 dmacint; /* DMA clear interrupt request */
96 u8 dmacerr; /* DMA clear error */
97 u8 dmassrt; /* DMA set start bit */
98 u8 dmacdne; /* DMA clear DONE status bit */
99 /* 0x20 */
100 u32 dmainth; /* DMA interrupt request high(ch63~32) */
101 u32 dmaintl; /* DMA interrupt request low(ch31~0) */
102 u32 dmaerrh; /* DMA error high(ch63~32) */
103 u32 dmaerrl; /* DMA error low(ch31~0) */
104 /* 0x30 */
105 u32 dmahrsh; /* DMA hw request status high(ch63~32) */
106 u32 dmahrsl; /* DMA hardware request status low(ch31~0) */
107 u32 dmaihsa; /* DMA interrupt high select AXE(ch63~32) */
108 u32 dmailsa; /* DMA interrupt low select AXE(ch31~0) */
109 /* 0x40 ~ 0xff */
110 u32 reserve0[48]; /* Reserved */
111 /* 0x100 */
112 u8 dchpri[MPC_DMA_CHANNELS];
113 /* DMA channels(0~63) priority */
114 };
115
116 struct __attribute__ ((__packed__)) mpc_dma_tcd {
117 /* 0x00 */
118 u32 saddr; /* Source address */
119
120 u32 smod:5; /* Source address modulo */
121 u32 ssize:3; /* Source data transfer size */
122 u32 dmod:5; /* Destination address modulo */
123 u32 dsize:3; /* Destination data transfer size */
124 u32 soff:16; /* Signed source address offset */
125
126 /* 0x08 */
127 u32 nbytes; /* Inner "minor" byte count */
128 u32 slast; /* Last source address adjustment */
129 u32 daddr; /* Destination address */
130
131 /* 0x14 */
132 u32 citer_elink:1; /* Enable channel-to-channel linking on
133 * minor loop complete
134 */
135 u32 citer_linkch:6; /* Link channel for minor loop complete */
136 u32 citer:9; /* Current "major" iteration count */
137 u32 doff:16; /* Signed destination address offset */
138
139 /* 0x18 */
140 u32 dlast_sga; /* Last Destination address adjustment/scatter
141 * gather address
142 */
143
144 /* 0x1c */
145 u32 biter_elink:1; /* Enable channel-to-channel linking on major
146 * loop complete
147 */
148 u32 biter_linkch:6;
149 u32 biter:9; /* Beginning "major" iteration count */
150 u32 bwc:2; /* Bandwidth control */
151 u32 major_linkch:6; /* Link channel number */
152 u32 done:1; /* Channel done */
153 u32 active:1; /* Channel active */
154 u32 major_elink:1; /* Enable channel-to-channel linking on major
155 * loop complete
156 */
157 u32 e_sg:1; /* Enable scatter/gather processing */
158 u32 d_req:1; /* Disable request */
159 u32 int_half:1; /* Enable an interrupt when major counter is
160 * half complete
161 */
162 u32 int_maj:1; /* Enable an interrupt when major iteration
163 * count completes
164 */
165 u32 start:1; /* Channel start */
166 };
167
168 struct mpc_dma_desc {
169 struct dma_async_tx_descriptor desc;
170 struct mpc_dma_tcd *tcd;
171 dma_addr_t tcd_paddr;
172 int error;
173 struct list_head node;
174 };
175
176 struct mpc_dma_chan {
177 struct dma_chan chan;
178 struct list_head free;
179 struct list_head prepared;
180 struct list_head queued;
181 struct list_head active;
182 struct list_head completed;
183 struct mpc_dma_tcd *tcd;
184 dma_addr_t tcd_paddr;
185 dma_cookie_t completed_cookie;
186
187 /* Lock for this structure */
188 spinlock_t lock;
189 };
190
191 struct mpc_dma {
192 struct dma_device dma;
193 struct tasklet_struct tasklet;
194 struct mpc_dma_chan channels[MPC_DMA_CHANNELS];
195 struct mpc_dma_regs __iomem *regs;
196 struct mpc_dma_tcd __iomem *tcd;
197 int irq;
198 uint error_status;
199
200 /* Lock for error_status field in this structure */
201 spinlock_t error_status_lock;
202 };
203
204 #define DRV_NAME "mpc512x_dma"
205
206 /* Convert struct dma_chan to struct mpc_dma_chan */
207 static inline struct mpc_dma_chan *dma_chan_to_mpc_dma_chan(struct dma_chan *c)
208 {
209 return container_of(c, struct mpc_dma_chan, chan);
210 }
211
212 /* Convert struct dma_chan to struct mpc_dma */
213 static inline struct mpc_dma *dma_chan_to_mpc_dma(struct dma_chan *c)
214 {
215 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(c);
216 return container_of(mchan, struct mpc_dma, channels[c->chan_id]);
217 }
218
219 /*
220 * Execute all queued DMA descriptors.
221 *
222 * Following requirements must be met while calling mpc_dma_execute():
223 * a) mchan->lock is acquired,
224 * b) mchan->active list is empty,
225 * c) mchan->queued list contains at least one entry.
226 */
227 static void mpc_dma_execute(struct mpc_dma_chan *mchan)
228 {
229 struct mpc_dma *mdma = dma_chan_to_mpc_dma(&mchan->chan);
230 struct mpc_dma_desc *first = NULL;
231 struct mpc_dma_desc *prev = NULL;
232 struct mpc_dma_desc *mdesc;
233 int cid = mchan->chan.chan_id;
234
235 /* Move all queued descriptors to active list */
236 list_splice_tail_init(&mchan->queued, &mchan->active);
237
238 /* Chain descriptors into one transaction */
239 list_for_each_entry(mdesc, &mchan->active, node) {
240 if (!first)
241 first = mdesc;
242
243 if (!prev) {
244 prev = mdesc;
245 continue;
246 }
247
248 prev->tcd->dlast_sga = mdesc->tcd_paddr;
249 prev->tcd->e_sg = 1;
250 mdesc->tcd->start = 1;
251
252 prev = mdesc;
253 }
254
255 prev->tcd->start = 0;
256 prev->tcd->int_maj = 1;
257
258 /* Send first descriptor in chain into hardware */
259 memcpy_toio(&mdma->tcd[cid], first->tcd, sizeof(struct mpc_dma_tcd));
260 out_8(&mdma->regs->dmassrt, cid);
261 }
262
263 /* Handle interrupt on one half of DMA controller (32 channels) */
264 static void mpc_dma_irq_process(struct mpc_dma *mdma, u32 is, u32 es, int off)
265 {
266 struct mpc_dma_chan *mchan;
267 struct mpc_dma_desc *mdesc;
268 u32 status = is | es;
269 int ch;
270
271 while ((ch = fls(status) - 1) >= 0) {
272 status &= ~(1 << ch);
273 mchan = &mdma->channels[ch + off];
274
275 spin_lock(&mchan->lock);
276
277 /* Check error status */
278 if (es & (1 << ch))
279 list_for_each_entry(mdesc, &mchan->active, node)
280 mdesc->error = -EIO;
281
282 /* Execute queued descriptors */
283 list_splice_tail_init(&mchan->active, &mchan->completed);
284 if (!list_empty(&mchan->queued))
285 mpc_dma_execute(mchan);
286
287 spin_unlock(&mchan->lock);
288 }
289 }
290
291 /* Interrupt handler */
292 static irqreturn_t mpc_dma_irq(int irq, void *data)
293 {
294 struct mpc_dma *mdma = data;
295 uint es;
296
297 /* Save error status register */
298 es = in_be32(&mdma->regs->dmaes);
299 spin_lock(&mdma->error_status_lock);
300 if ((es & MPC_DMA_DMAES_VLD) && mdma->error_status == 0)
301 mdma->error_status = es;
302 spin_unlock(&mdma->error_status_lock);
303
304 /* Handle interrupt on each channel */
305 mpc_dma_irq_process(mdma, in_be32(&mdma->regs->dmainth),
306 in_be32(&mdma->regs->dmaerrh), 32);
307 mpc_dma_irq_process(mdma, in_be32(&mdma->regs->dmaintl),
308 in_be32(&mdma->regs->dmaerrl), 0);
309
310 /* Ack interrupt on all channels */
311 out_be32(&mdma->regs->dmainth, 0xFFFFFFFF);
312 out_be32(&mdma->regs->dmaintl, 0xFFFFFFFF);
313 out_be32(&mdma->regs->dmaerrh, 0xFFFFFFFF);
314 out_be32(&mdma->regs->dmaerrl, 0xFFFFFFFF);
315
316 /* Schedule tasklet */
317 tasklet_schedule(&mdma->tasklet);
318
319 return IRQ_HANDLED;
320 }
321
322 /* DMA Tasklet */
323 static void mpc_dma_tasklet(unsigned long data)
324 {
325 struct mpc_dma *mdma = (void *)data;
326 dma_cookie_t last_cookie = 0;
327 struct mpc_dma_chan *mchan;
328 struct mpc_dma_desc *mdesc;
329 struct dma_async_tx_descriptor *desc;
330 unsigned long flags;
331 LIST_HEAD(list);
332 uint es;
333 int i;
334
335 spin_lock_irqsave(&mdma->error_status_lock, flags);
336 es = mdma->error_status;
337 mdma->error_status = 0;
338 spin_unlock_irqrestore(&mdma->error_status_lock, flags);
339
340 /* Print nice error report */
341 if (es) {
342 dev_err(mdma->dma.dev,
343 "Hardware reported following error(s) on channel %u:\n",
344 MPC_DMA_DMAES_ERRCHN(es));
345
346 if (es & MPC_DMA_DMAES_GPE)
347 dev_err(mdma->dma.dev, "- Group Priority Error\n");
348 if (es & MPC_DMA_DMAES_CPE)
349 dev_err(mdma->dma.dev, "- Channel Priority Error\n");
350 if (es & MPC_DMA_DMAES_SAE)
351 dev_err(mdma->dma.dev, "- Source Address Error\n");
352 if (es & MPC_DMA_DMAES_SOE)
353 dev_err(mdma->dma.dev, "- Source Offset"
354 " Configuration Error\n");
355 if (es & MPC_DMA_DMAES_DAE)
356 dev_err(mdma->dma.dev, "- Destination Address"
357 " Error\n");
358 if (es & MPC_DMA_DMAES_DOE)
359 dev_err(mdma->dma.dev, "- Destination Offset"
360 " Configuration Error\n");
361 if (es & MPC_DMA_DMAES_NCE)
362 dev_err(mdma->dma.dev, "- NBytes/Citter"
363 " Configuration Error\n");
364 if (es & MPC_DMA_DMAES_SGE)
365 dev_err(mdma->dma.dev, "- Scatter/Gather"
366 " Configuration Error\n");
367 if (es & MPC_DMA_DMAES_SBE)
368 dev_err(mdma->dma.dev, "- Source Bus Error\n");
369 if (es & MPC_DMA_DMAES_DBE)
370 dev_err(mdma->dma.dev, "- Destination Bus Error\n");
371 }
372
373 for (i = 0; i < mdma->dma.chancnt; i++) {
374 mchan = &mdma->channels[i];
375
376 /* Get all completed descriptors */
377 spin_lock_irqsave(&mchan->lock, flags);
378 if (!list_empty(&mchan->completed))
379 list_splice_tail_init(&mchan->completed, &list);
380 spin_unlock_irqrestore(&mchan->lock, flags);
381
382 if (list_empty(&list))
383 continue;
384
385 /* Execute callbacks and run dependencies */
386 list_for_each_entry(mdesc, &list, node) {
387 desc = &mdesc->desc;
388
389 if (desc->callback)
390 desc->callback(desc->callback_param);
391
392 last_cookie = desc->cookie;
393 dma_run_dependencies(desc);
394 }
395
396 /* Free descriptors */
397 spin_lock_irqsave(&mchan->lock, flags);
398 list_splice_tail_init(&list, &mchan->free);
399 mchan->completed_cookie = last_cookie;
400 spin_unlock_irqrestore(&mchan->lock, flags);
401 }
402 }
403
404 /* Submit descriptor to hardware */
405 static dma_cookie_t mpc_dma_tx_submit(struct dma_async_tx_descriptor *txd)
406 {
407 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(txd->chan);
408 struct mpc_dma_desc *mdesc;
409 unsigned long flags;
410 dma_cookie_t cookie;
411
412 mdesc = container_of(txd, struct mpc_dma_desc, desc);
413
414 spin_lock_irqsave(&mchan->lock, flags);
415
416 /* Move descriptor to queue */
417 list_move_tail(&mdesc->node, &mchan->queued);
418
419 /* If channel is idle, execute all queued descriptors */
420 if (list_empty(&mchan->active))
421 mpc_dma_execute(mchan);
422
423 /* Update cookie */
424 cookie = mchan->chan.cookie + 1;
425 if (cookie <= 0)
426 cookie = 1;
427
428 mchan->chan.cookie = cookie;
429 mdesc->desc.cookie = cookie;
430
431 spin_unlock_irqrestore(&mchan->lock, flags);
432
433 return cookie;
434 }
435
436 /* Alloc channel resources */
437 static int mpc_dma_alloc_chan_resources(struct dma_chan *chan)
438 {
439 struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan);
440 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
441 struct mpc_dma_desc *mdesc;
442 struct mpc_dma_tcd *tcd;
443 dma_addr_t tcd_paddr;
444 unsigned long flags;
445 LIST_HEAD(descs);
446 int i;
447
448 /* Alloc DMA memory for Transfer Control Descriptors */
449 tcd = dma_alloc_coherent(mdma->dma.dev,
450 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
451 &tcd_paddr, GFP_KERNEL);
452 if (!tcd)
453 return -ENOMEM;
454
455 /* Alloc descriptors for this channel */
456 for (i = 0; i < MPC_DMA_DESCRIPTORS; i++) {
457 mdesc = kzalloc(sizeof(struct mpc_dma_desc), GFP_KERNEL);
458 if (!mdesc) {
459 dev_notice(mdma->dma.dev, "Memory allocation error. "
460 "Allocated only %u descriptors\n", i);
461 break;
462 }
463
464 dma_async_tx_descriptor_init(&mdesc->desc, chan);
465 mdesc->desc.flags = DMA_CTRL_ACK;
466 mdesc->desc.tx_submit = mpc_dma_tx_submit;
467
468 mdesc->tcd = &tcd[i];
469 mdesc->tcd_paddr = tcd_paddr + (i * sizeof(struct mpc_dma_tcd));
470
471 list_add_tail(&mdesc->node, &descs);
472 }
473
474 /* Return error only if no descriptors were allocated */
475 if (i == 0) {
476 dma_free_coherent(mdma->dma.dev,
477 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
478 tcd, tcd_paddr);
479 return -ENOMEM;
480 }
481
482 spin_lock_irqsave(&mchan->lock, flags);
483 mchan->tcd = tcd;
484 mchan->tcd_paddr = tcd_paddr;
485 list_splice_tail_init(&descs, &mchan->free);
486 spin_unlock_irqrestore(&mchan->lock, flags);
487
488 /* Enable Error Interrupt */
489 out_8(&mdma->regs->dmaseei, chan->chan_id);
490
491 return 0;
492 }
493
494 /* Free channel resources */
495 static void mpc_dma_free_chan_resources(struct dma_chan *chan)
496 {
497 struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan);
498 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
499 struct mpc_dma_desc *mdesc, *tmp;
500 struct mpc_dma_tcd *tcd;
501 dma_addr_t tcd_paddr;
502 unsigned long flags;
503 LIST_HEAD(descs);
504
505 spin_lock_irqsave(&mchan->lock, flags);
506
507 /* Channel must be idle */
508 BUG_ON(!list_empty(&mchan->prepared));
509 BUG_ON(!list_empty(&mchan->queued));
510 BUG_ON(!list_empty(&mchan->active));
511 BUG_ON(!list_empty(&mchan->completed));
512
513 /* Move data */
514 list_splice_tail_init(&mchan->free, &descs);
515 tcd = mchan->tcd;
516 tcd_paddr = mchan->tcd_paddr;
517
518 spin_unlock_irqrestore(&mchan->lock, flags);
519
520 /* Free DMA memory used by descriptors */
521 dma_free_coherent(mdma->dma.dev,
522 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
523 tcd, tcd_paddr);
524
525 /* Free descriptors */
526 list_for_each_entry_safe(mdesc, tmp, &descs, node)
527 kfree(mdesc);
528
529 /* Disable Error Interrupt */
530 out_8(&mdma->regs->dmaceei, chan->chan_id);
531 }
532
533 /* Send all pending descriptor to hardware */
534 static void mpc_dma_issue_pending(struct dma_chan *chan)
535 {
536 /*
537 * We are posting descriptors to the hardware as soon as
538 * they are ready, so this function does nothing.
539 */
540 }
541
542 /* Check request completion status */
543 static enum dma_status
544 mpc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
545 struct dma_tx_state *txstate)
546 {
547 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
548 unsigned long flags;
549 dma_cookie_t last_used;
550 dma_cookie_t last_complete;
551
552 spin_lock_irqsave(&mchan->lock, flags);
553 last_used = mchan->chan.cookie;
554 last_complete = mchan->completed_cookie;
555 spin_unlock_irqrestore(&mchan->lock, flags);
556
557 dma_set_tx_state(txstate, last_complete, last_used, 0);
558 return dma_async_is_complete(cookie, last_complete, last_used);
559 }
560
561 /* Prepare descriptor for memory to memory copy */
562 static struct dma_async_tx_descriptor *
563 mpc_dma_prep_memcpy(struct dma_chan *chan, dma_addr_t dst, dma_addr_t src,
564 size_t len, unsigned long flags)
565 {
566 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
567 struct mpc_dma_desc *mdesc = NULL;
568 struct mpc_dma_tcd *tcd;
569 unsigned long iflags;
570
571 /* Get free descriptor */
572 spin_lock_irqsave(&mchan->lock, iflags);
573 if (!list_empty(&mchan->free)) {
574 mdesc = list_first_entry(&mchan->free, struct mpc_dma_desc,
575 node);
576 list_del(&mdesc->node);
577 }
578 spin_unlock_irqrestore(&mchan->lock, iflags);
579
580 if (!mdesc)
581 return NULL;
582
583 mdesc->error = 0;
584 tcd = mdesc->tcd;
585
586 /* Prepare Transfer Control Descriptor for this transaction */
587 memset(tcd, 0, sizeof(struct mpc_dma_tcd));
588
589 if (IS_ALIGNED(src | dst | len, 32)) {
590 tcd->ssize = MPC_DMA_TSIZE_32;
591 tcd->dsize = MPC_DMA_TSIZE_32;
592 tcd->soff = 32;
593 tcd->doff = 32;
594 } else if (IS_ALIGNED(src | dst | len, 16)) {
595 tcd->ssize = MPC_DMA_TSIZE_16;
596 tcd->dsize = MPC_DMA_TSIZE_16;
597 tcd->soff = 16;
598 tcd->doff = 16;
599 } else if (IS_ALIGNED(src | dst | len, 4)) {
600 tcd->ssize = MPC_DMA_TSIZE_4;
601 tcd->dsize = MPC_DMA_TSIZE_4;
602 tcd->soff = 4;
603 tcd->doff = 4;
604 } else if (IS_ALIGNED(src | dst | len, 2)) {
605 tcd->ssize = MPC_DMA_TSIZE_2;
606 tcd->dsize = MPC_DMA_TSIZE_2;
607 tcd->soff = 2;
608 tcd->doff = 2;
609 } else {
610 tcd->ssize = MPC_DMA_TSIZE_1;
611 tcd->dsize = MPC_DMA_TSIZE_1;
612 tcd->soff = 1;
613 tcd->doff = 1;
614 }
615
616 tcd->saddr = src;
617 tcd->daddr = dst;
618 tcd->nbytes = len;
619 tcd->biter = 1;
620 tcd->citer = 1;
621
622 /* Place descriptor in prepared list */
623 spin_lock_irqsave(&mchan->lock, iflags);
624 list_add_tail(&mdesc->node, &mchan->prepared);
625 spin_unlock_irqrestore(&mchan->lock, iflags);
626
627 return &mdesc->desc;
628 }
629
630 static int __devinit mpc_dma_probe(struct platform_device *op,
631 const struct of_device_id *match)
632 {
633 struct device_node *dn = op->dev.of_node;
634 struct device *dev = &op->dev;
635 struct dma_device *dma;
636 struct mpc_dma *mdma;
637 struct mpc_dma_chan *mchan;
638 struct resource res;
639 ulong regs_start, regs_size;
640 int retval, i;
641
642 mdma = devm_kzalloc(dev, sizeof(struct mpc_dma), GFP_KERNEL);
643 if (!mdma) {
644 dev_err(dev, "Memory exhausted!\n");
645 return -ENOMEM;
646 }
647
648 mdma->irq = irq_of_parse_and_map(dn, 0);
649 if (mdma->irq == NO_IRQ) {
650 dev_err(dev, "Error mapping IRQ!\n");
651 return -EINVAL;
652 }
653
654 retval = of_address_to_resource(dn, 0, &res);
655 if (retval) {
656 dev_err(dev, "Error parsing memory region!\n");
657 return retval;
658 }
659
660 regs_start = res.start;
661 regs_size = resource_size(&res);
662
663 if (!devm_request_mem_region(dev, regs_start, regs_size, DRV_NAME)) {
664 dev_err(dev, "Error requesting memory region!\n");
665 return -EBUSY;
666 }
667
668 mdma->regs = devm_ioremap(dev, regs_start, regs_size);
669 if (!mdma->regs) {
670 dev_err(dev, "Error mapping memory region!\n");
671 return -ENOMEM;
672 }
673
674 mdma->tcd = (struct mpc_dma_tcd *)((u8 *)(mdma->regs)
675 + MPC_DMA_TCD_OFFSET);
676
677 retval = devm_request_irq(dev, mdma->irq, &mpc_dma_irq, 0, DRV_NAME,
678 mdma);
679 if (retval) {
680 dev_err(dev, "Error requesting IRQ!\n");
681 return -EINVAL;
682 }
683
684 spin_lock_init(&mdma->error_status_lock);
685
686 dma = &mdma->dma;
687 dma->dev = dev;
688 dma->chancnt = MPC_DMA_CHANNELS;
689 dma->device_alloc_chan_resources = mpc_dma_alloc_chan_resources;
690 dma->device_free_chan_resources = mpc_dma_free_chan_resources;
691 dma->device_issue_pending = mpc_dma_issue_pending;
692 dma->device_tx_status = mpc_dma_tx_status;
693 dma->device_prep_dma_memcpy = mpc_dma_prep_memcpy;
694
695 INIT_LIST_HEAD(&dma->channels);
696 dma_cap_set(DMA_MEMCPY, dma->cap_mask);
697
698 for (i = 0; i < dma->chancnt; i++) {
699 mchan = &mdma->channels[i];
700
701 mchan->chan.device = dma;
702 mchan->chan.chan_id = i;
703 mchan->chan.cookie = 1;
704 mchan->completed_cookie = mchan->chan.cookie;
705
706 INIT_LIST_HEAD(&mchan->free);
707 INIT_LIST_HEAD(&mchan->prepared);
708 INIT_LIST_HEAD(&mchan->queued);
709 INIT_LIST_HEAD(&mchan->active);
710 INIT_LIST_HEAD(&mchan->completed);
711
712 spin_lock_init(&mchan->lock);
713 list_add_tail(&mchan->chan.device_node, &dma->channels);
714 }
715
716 tasklet_init(&mdma->tasklet, mpc_dma_tasklet, (unsigned long)mdma);
717
718 /*
719 * Configure DMA Engine:
720 * - Dynamic clock,
721 * - Round-robin group arbitration,
722 * - Round-robin channel arbitration.
723 */
724 out_be32(&mdma->regs->dmacr, MPC_DMA_DMACR_EDCG |
725 MPC_DMA_DMACR_ERGA | MPC_DMA_DMACR_ERCA);
726
727 /* Disable hardware DMA requests */
728 out_be32(&mdma->regs->dmaerqh, 0);
729 out_be32(&mdma->regs->dmaerql, 0);
730
731 /* Disable error interrupts */
732 out_be32(&mdma->regs->dmaeeih, 0);
733 out_be32(&mdma->regs->dmaeeil, 0);
734
735 /* Clear interrupts status */
736 out_be32(&mdma->regs->dmainth, 0xFFFFFFFF);
737 out_be32(&mdma->regs->dmaintl, 0xFFFFFFFF);
738 out_be32(&mdma->regs->dmaerrh, 0xFFFFFFFF);
739 out_be32(&mdma->regs->dmaerrl, 0xFFFFFFFF);
740
741 /* Route interrupts to IPIC */
742 out_be32(&mdma->regs->dmaihsa, 0);
743 out_be32(&mdma->regs->dmailsa, 0);
744
745 /* Register DMA engine */
746 dev_set_drvdata(dev, mdma);
747 retval = dma_async_device_register(dma);
748 if (retval) {
749 devm_free_irq(dev, mdma->irq, mdma);
750 irq_dispose_mapping(mdma->irq);
751 }
752
753 return retval;
754 }
755
756 static int __devexit mpc_dma_remove(struct platform_device *op)
757 {
758 struct device *dev = &op->dev;
759 struct mpc_dma *mdma = dev_get_drvdata(dev);
760
761 dma_async_device_unregister(&mdma->dma);
762 devm_free_irq(dev, mdma->irq, mdma);
763 irq_dispose_mapping(mdma->irq);
764
765 return 0;
766 }
767
768 static struct of_device_id mpc_dma_match[] = {
769 { .compatible = "fsl,mpc5121-dma", },
770 {},
771 };
772
773 static struct of_platform_driver mpc_dma_driver = {
774 .probe = mpc_dma_probe,
775 .remove = __devexit_p(mpc_dma_remove),
776 .driver = {
777 .name = DRV_NAME,
778 .owner = THIS_MODULE,
779 .of_match_table = mpc_dma_match,
780 },
781 };
782
783 static int __init mpc_dma_init(void)
784 {
785 return of_register_platform_driver(&mpc_dma_driver);
786 }
787 module_init(mpc_dma_init);
788
789 static void __exit mpc_dma_exit(void)
790 {
791 of_unregister_platform_driver(&mpc_dma_driver);
792 }
793 module_exit(mpc_dma_exit);
794
795 MODULE_LICENSE("GPL");
796 MODULE_AUTHOR("Piotr Ziecik <kosmo@semihalf.com>");
Linus' kernel tree