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powerpc/512x: fix the hanged dma transfer issue
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / dma / mpc512x_dma.c
blob071752727718dbac0470c739520f9879e0bf05d0
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->int_maj = 1;
256
257 /* Send first descriptor in chain into hardware */
258 memcpy_toio(&mdma->tcd[cid], first->tcd, sizeof(struct mpc_dma_tcd));
259
260 if (first != prev)
261 mdma->tcd[cid].e_sg = 1;
262 out_8(&mdma->regs->dmassrt, cid);
263 }
264
265 /* Handle interrupt on one half of DMA controller (32 channels) */
266 static void mpc_dma_irq_process(struct mpc_dma *mdma, u32 is, u32 es, int off)
267 {
268 struct mpc_dma_chan *mchan;
269 struct mpc_dma_desc *mdesc;
270 u32 status = is | es;
271 int ch;
272
273 while ((ch = fls(status) - 1) >= 0) {
274 status &= ~(1 << ch);
275 mchan = &mdma->channels[ch + off];
276
277 spin_lock(&mchan->lock);
278
279 out_8(&mdma->regs->dmacint, ch + off);
280 out_8(&mdma->regs->dmacerr, ch + off);
281
282 /* Check error status */
283 if (es & (1 << ch))
284 list_for_each_entry(mdesc, &mchan->active, node)
285 mdesc->error = -EIO;
286
287 /* Execute queued descriptors */
288 list_splice_tail_init(&mchan->active, &mchan->completed);
289 if (!list_empty(&mchan->queued))
290 mpc_dma_execute(mchan);
291
292 spin_unlock(&mchan->lock);
293 }
294 }
295
296 /* Interrupt handler */
297 static irqreturn_t mpc_dma_irq(int irq, void *data)
298 {
299 struct mpc_dma *mdma = data;
300 uint es;
301
302 /* Save error status register */
303 es = in_be32(&mdma->regs->dmaes);
304 spin_lock(&mdma->error_status_lock);
305 if ((es & MPC_DMA_DMAES_VLD) && mdma->error_status == 0)
306 mdma->error_status = es;
307 spin_unlock(&mdma->error_status_lock);
308
309 /* Handle interrupt on each channel */
310 mpc_dma_irq_process(mdma, in_be32(&mdma->regs->dmainth),
311 in_be32(&mdma->regs->dmaerrh), 32);
312 mpc_dma_irq_process(mdma, in_be32(&mdma->regs->dmaintl),
313 in_be32(&mdma->regs->dmaerrl), 0);
314
315 /* Schedule tasklet */
316 tasklet_schedule(&mdma->tasklet);
317
318 return IRQ_HANDLED;
319 }
320
321 /* DMA Tasklet */
322 static void mpc_dma_tasklet(unsigned long data)
323 {
324 struct mpc_dma *mdma = (void *)data;
325 dma_cookie_t last_cookie = 0;
326 struct mpc_dma_chan *mchan;
327 struct mpc_dma_desc *mdesc;
328 struct dma_async_tx_descriptor *desc;
329 unsigned long flags;
330 LIST_HEAD(list);
331 uint es;
332 int i;
333
334 spin_lock_irqsave(&mdma->error_status_lock, flags);
335 es = mdma->error_status;
336 mdma->error_status = 0;
337 spin_unlock_irqrestore(&mdma->error_status_lock, flags);
338
339 /* Print nice error report */
340 if (es) {
341 dev_err(mdma->dma.dev,
342 "Hardware reported following error(s) on channel %u:\n",
343 MPC_DMA_DMAES_ERRCHN(es));
344
345 if (es & MPC_DMA_DMAES_GPE)
346 dev_err(mdma->dma.dev, "- Group Priority Error\n");
347 if (es & MPC_DMA_DMAES_CPE)
348 dev_err(mdma->dma.dev, "- Channel Priority Error\n");
349 if (es & MPC_DMA_DMAES_SAE)
350 dev_err(mdma->dma.dev, "- Source Address Error\n");
351 if (es & MPC_DMA_DMAES_SOE)
352 dev_err(mdma->dma.dev, "- Source Offset"
353 " Configuration Error\n");
354 if (es & MPC_DMA_DMAES_DAE)
355 dev_err(mdma->dma.dev, "- Destination Address"
356 " Error\n");
357 if (es & MPC_DMA_DMAES_DOE)
358 dev_err(mdma->dma.dev, "- Destination Offset"
359 " Configuration Error\n");
360 if (es & MPC_DMA_DMAES_NCE)
361 dev_err(mdma->dma.dev, "- NBytes/Citter"
362 " Configuration Error\n");
363 if (es & MPC_DMA_DMAES_SGE)
364 dev_err(mdma->dma.dev, "- Scatter/Gather"
365 " Configuration Error\n");
366 if (es & MPC_DMA_DMAES_SBE)
367 dev_err(mdma->dma.dev, "- Source Bus Error\n");
368 if (es & MPC_DMA_DMAES_DBE)
369 dev_err(mdma->dma.dev, "- Destination Bus Error\n");
370 }
371
372 for (i = 0; i < mdma->dma.chancnt; i++) {
373 mchan = &mdma->channels[i];
374
375 /* Get all completed descriptors */
376 spin_lock_irqsave(&mchan->lock, flags);
377 if (!list_empty(&mchan->completed))
378 list_splice_tail_init(&mchan->completed, &list);
379 spin_unlock_irqrestore(&mchan->lock, flags);
380
381 if (list_empty(&list))
382 continue;
383
384 /* Execute callbacks and run dependencies */
385 list_for_each_entry(mdesc, &list, node) {
386 desc = &mdesc->desc;
387
388 if (desc->callback)
389 desc->callback(desc->callback_param);
390
391 last_cookie = desc->cookie;
392 dma_run_dependencies(desc);
393 }
394
395 /* Free descriptors */
396 spin_lock_irqsave(&mchan->lock, flags);
397 list_splice_tail_init(&list, &mchan->free);
398 mchan->completed_cookie = last_cookie;
399 spin_unlock_irqrestore(&mchan->lock, flags);
400 }
401 }
402
403 /* Submit descriptor to hardware */
404 static dma_cookie_t mpc_dma_tx_submit(struct dma_async_tx_descriptor *txd)
405 {
406 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(txd->chan);
407 struct mpc_dma_desc *mdesc;
408 unsigned long flags;
409 dma_cookie_t cookie;
410
411 mdesc = container_of(txd, struct mpc_dma_desc, desc);
412
413 spin_lock_irqsave(&mchan->lock, flags);
414
415 /* Move descriptor to queue */
416 list_move_tail(&mdesc->node, &mchan->queued);
417
418 /* If channel is idle, execute all queued descriptors */
419 if (list_empty(&mchan->active))
420 mpc_dma_execute(mchan);
421
422 /* Update cookie */
423 cookie = mchan->chan.cookie + 1;
424 if (cookie <= 0)
425 cookie = 1;
426
427 mchan->chan.cookie = cookie;
428 mdesc->desc.cookie = cookie;
429
430 spin_unlock_irqrestore(&mchan->lock, flags);
431
432 return cookie;
433 }
434
435 /* Alloc channel resources */
436 static int mpc_dma_alloc_chan_resources(struct dma_chan *chan)
437 {
438 struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan);
439 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
440 struct mpc_dma_desc *mdesc;
441 struct mpc_dma_tcd *tcd;
442 dma_addr_t tcd_paddr;
443 unsigned long flags;
444 LIST_HEAD(descs);
445 int i;
446
447 /* Alloc DMA memory for Transfer Control Descriptors */
448 tcd = dma_alloc_coherent(mdma->dma.dev,
449 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
450 &tcd_paddr, GFP_KERNEL);
451 if (!tcd)
452 return -ENOMEM;
453
454 /* Alloc descriptors for this channel */
455 for (i = 0; i < MPC_DMA_DESCRIPTORS; i++) {
456 mdesc = kzalloc(sizeof(struct mpc_dma_desc), GFP_KERNEL);
457 if (!mdesc) {
458 dev_notice(mdma->dma.dev, "Memory allocation error. "
459 "Allocated only %u descriptors\n", i);
460 break;
461 }
462
463 dma_async_tx_descriptor_init(&mdesc->desc, chan);
464 mdesc->desc.flags = DMA_CTRL_ACK;
465 mdesc->desc.tx_submit = mpc_dma_tx_submit;
466
467 mdesc->tcd = &tcd[i];
468 mdesc->tcd_paddr = tcd_paddr + (i * sizeof(struct mpc_dma_tcd));
469
470 list_add_tail(&mdesc->node, &descs);
471 }
472
473 /* Return error only if no descriptors were allocated */
474 if (i == 0) {
475 dma_free_coherent(mdma->dma.dev,
476 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
477 tcd, tcd_paddr);
478 return -ENOMEM;
479 }
480
481 spin_lock_irqsave(&mchan->lock, flags);
482 mchan->tcd = tcd;
483 mchan->tcd_paddr = tcd_paddr;
484 list_splice_tail_init(&descs, &mchan->free);
485 spin_unlock_irqrestore(&mchan->lock, flags);
486
487 /* Enable Error Interrupt */
488 out_8(&mdma->regs->dmaseei, chan->chan_id);
489
490 return 0;
491 }
492
493 /* Free channel resources */
494 static void mpc_dma_free_chan_resources(struct dma_chan *chan)
495 {
496 struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan);
497 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
498 struct mpc_dma_desc *mdesc, *tmp;
499 struct mpc_dma_tcd *tcd;
500 dma_addr_t tcd_paddr;
501 unsigned long flags;
502 LIST_HEAD(descs);
503
504 spin_lock_irqsave(&mchan->lock, flags);
505
506 /* Channel must be idle */
507 BUG_ON(!list_empty(&mchan->prepared));
508 BUG_ON(!list_empty(&mchan->queued));
509 BUG_ON(!list_empty(&mchan->active));
510 BUG_ON(!list_empty(&mchan->completed));
511
512 /* Move data */
513 list_splice_tail_init(&mchan->free, &descs);
514 tcd = mchan->tcd;
515 tcd_paddr = mchan->tcd_paddr;
516
517 spin_unlock_irqrestore(&mchan->lock, flags);
518
519 /* Free DMA memory used by descriptors */
520 dma_free_coherent(mdma->dma.dev,
521 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
522 tcd, tcd_paddr);
523
524 /* Free descriptors */
525 list_for_each_entry_safe(mdesc, tmp, &descs, node)
526 kfree(mdesc);
527
528 /* Disable Error Interrupt */
529 out_8(&mdma->regs->dmaceei, chan->chan_id);
530 }
531
532 /* Send all pending descriptor to hardware */
533 static void mpc_dma_issue_pending(struct dma_chan *chan)
534 {
535 /*
536 * We are posting descriptors to the hardware as soon as
537 * they are ready, so this function does nothing.
538 */
539 }
540
541 /* Check request completion status */
542 static enum dma_status
543 mpc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
544 struct dma_tx_state *txstate)
545 {
546 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
547 unsigned long flags;
548 dma_cookie_t last_used;
549 dma_cookie_t last_complete;
550
551 spin_lock_irqsave(&mchan->lock, flags);
552 last_used = mchan->chan.cookie;
553 last_complete = mchan->completed_cookie;
554 spin_unlock_irqrestore(&mchan->lock, flags);
555
556 dma_set_tx_state(txstate, last_complete, last_used, 0);
557 return dma_async_is_complete(cookie, last_complete, last_used);
558 }
559
560 /* Prepare descriptor for memory to memory copy */
561 static struct dma_async_tx_descriptor *
562 mpc_dma_prep_memcpy(struct dma_chan *chan, dma_addr_t dst, dma_addr_t src,
563 size_t len, unsigned long flags)
564 {
565 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
566 struct mpc_dma_desc *mdesc = NULL;
567 struct mpc_dma_tcd *tcd;
568 unsigned long iflags;
569
570 /* Get free descriptor */
571 spin_lock_irqsave(&mchan->lock, iflags);
572 if (!list_empty(&mchan->free)) {
573 mdesc = list_first_entry(&mchan->free, struct mpc_dma_desc,
574 node);
575 list_del(&mdesc->node);
576 }
577 spin_unlock_irqrestore(&mchan->lock, iflags);
578
579 if (!mdesc)
580 return NULL;
581
582 mdesc->error = 0;
583 tcd = mdesc->tcd;
584
585 /* Prepare Transfer Control Descriptor for this transaction */
586 memset(tcd, 0, sizeof(struct mpc_dma_tcd));
587
588 if (IS_ALIGNED(src | dst | len, 32)) {
589 tcd->ssize = MPC_DMA_TSIZE_32;
590 tcd->dsize = MPC_DMA_TSIZE_32;
591 tcd->soff = 32;
592 tcd->doff = 32;
593 } else if (IS_ALIGNED(src | dst | len, 16)) {
594 tcd->ssize = MPC_DMA_TSIZE_16;
595 tcd->dsize = MPC_DMA_TSIZE_16;
596 tcd->soff = 16;
597 tcd->doff = 16;
598 } else if (IS_ALIGNED(src | dst | len, 4)) {
599 tcd->ssize = MPC_DMA_TSIZE_4;
600 tcd->dsize = MPC_DMA_TSIZE_4;
601 tcd->soff = 4;
602 tcd->doff = 4;
603 } else if (IS_ALIGNED(src | dst | len, 2)) {
604 tcd->ssize = MPC_DMA_TSIZE_2;
605 tcd->dsize = MPC_DMA_TSIZE_2;
606 tcd->soff = 2;
607 tcd->doff = 2;
608 } else {
609 tcd->ssize = MPC_DMA_TSIZE_1;
610 tcd->dsize = MPC_DMA_TSIZE_1;
611 tcd->soff = 1;
612 tcd->doff = 1;
613 }
614
615 tcd->saddr = src;
616 tcd->daddr = dst;
617 tcd->nbytes = len;
618 tcd->biter = 1;
619 tcd->citer = 1;
620
621 /* Place descriptor in prepared list */
622 spin_lock_irqsave(&mchan->lock, iflags);
623 list_add_tail(&mdesc->node, &mchan->prepared);
624 spin_unlock_irqrestore(&mchan->lock, iflags);
625
626 return &mdesc->desc;
627 }
628
629 static int __devinit mpc_dma_probe(struct platform_device *op,
630 const struct of_device_id *match)
631 {
632 struct device_node *dn = op->dev.of_node;
633 struct device *dev = &op->dev;
634 struct dma_device *dma;
635 struct mpc_dma *mdma;
636 struct mpc_dma_chan *mchan;
637 struct resource res;
638 ulong regs_start, regs_size;
639 int retval, i;
640
641 mdma = devm_kzalloc(dev, sizeof(struct mpc_dma), GFP_KERNEL);
642 if (!mdma) {
643 dev_err(dev, "Memory exhausted!\n");
644 return -ENOMEM;
645 }
646
647 mdma->irq = irq_of_parse_and_map(dn, 0);
648 if (mdma->irq == NO_IRQ) {
649 dev_err(dev, "Error mapping IRQ!\n");
650 return -EINVAL;
651 }
652
653 retval = of_address_to_resource(dn, 0, &res);
654 if (retval) {
655 dev_err(dev, "Error parsing memory region!\n");
656 return retval;
657 }
658
659 regs_start = res.start;
660 regs_size = resource_size(&res);
661
662 if (!devm_request_mem_region(dev, regs_start, regs_size, DRV_NAME)) {
663 dev_err(dev, "Error requesting memory region!\n");
664 return -EBUSY;
665 }
666
667 mdma->regs = devm_ioremap(dev, regs_start, regs_size);
668 if (!mdma->regs) {
669 dev_err(dev, "Error mapping memory region!\n");
670 return -ENOMEM;
671 }
672
673 mdma->tcd = (struct mpc_dma_tcd *)((u8 *)(mdma->regs)
674 + MPC_DMA_TCD_OFFSET);
675
676 retval = devm_request_irq(dev, mdma->irq, &mpc_dma_irq, 0, DRV_NAME,
677 mdma);
678 if (retval) {
679 dev_err(dev, "Error requesting IRQ!\n");
680 return -EINVAL;
681 }
682
683 spin_lock_init(&mdma->error_status_lock);
684
685 dma = &mdma->dma;
686 dma->dev = dev;
687 dma->chancnt = MPC_DMA_CHANNELS;
688 dma->device_alloc_chan_resources = mpc_dma_alloc_chan_resources;
689 dma->device_free_chan_resources = mpc_dma_free_chan_resources;
690 dma->device_issue_pending = mpc_dma_issue_pending;
691 dma->device_tx_status = mpc_dma_tx_status;
692 dma->device_prep_dma_memcpy = mpc_dma_prep_memcpy;
693
694 INIT_LIST_HEAD(&dma->channels);
695 dma_cap_set(DMA_MEMCPY, dma->cap_mask);
696
697 for (i = 0; i < dma->chancnt; i++) {
698 mchan = &mdma->channels[i];
699
700 mchan->chan.device = dma;
701 mchan->chan.chan_id = i;
702 mchan->chan.cookie = 1;
703 mchan->completed_cookie = mchan->chan.cookie;
704
705 INIT_LIST_HEAD(&mchan->free);
706 INIT_LIST_HEAD(&mchan->prepared);
707 INIT_LIST_HEAD(&mchan->queued);
708 INIT_LIST_HEAD(&mchan->active);
709 INIT_LIST_HEAD(&mchan->completed);
710
711 spin_lock_init(&mchan->lock);
712 list_add_tail(&mchan->chan.device_node, &dma->channels);
713 }
714
715 tasklet_init(&mdma->tasklet, mpc_dma_tasklet, (unsigned long)mdma);
716
717 /*
718 * Configure DMA Engine:
719 * - Dynamic clock,
720 * - Round-robin group arbitration,
721 * - Round-robin channel arbitration.
722 */
723 out_be32(&mdma->regs->dmacr, MPC_DMA_DMACR_EDCG |
724 MPC_DMA_DMACR_ERGA | MPC_DMA_DMACR_ERCA);
725
726 /* Disable hardware DMA requests */
727 out_be32(&mdma->regs->dmaerqh, 0);
728 out_be32(&mdma->regs->dmaerql, 0);
729
730 /* Disable error interrupts */
731 out_be32(&mdma->regs->dmaeeih, 0);
732 out_be32(&mdma->regs->dmaeeil, 0);
733
734 /* Clear interrupts status */
735 out_be32(&mdma->regs->dmainth, 0xFFFFFFFF);
736 out_be32(&mdma->regs->dmaintl, 0xFFFFFFFF);
737 out_be32(&mdma->regs->dmaerrh, 0xFFFFFFFF);
738 out_be32(&mdma->regs->dmaerrl, 0xFFFFFFFF);
739
740 /* Route interrupts to IPIC */
741 out_be32(&mdma->regs->dmaihsa, 0);
742 out_be32(&mdma->regs->dmailsa, 0);
743
744 /* Register DMA engine */
745 dev_set_drvdata(dev, mdma);
746 retval = dma_async_device_register(dma);
747 if (retval) {
748 devm_free_irq(dev, mdma->irq, mdma);
749 irq_dispose_mapping(mdma->irq);
750 }
751
752 return retval;
753 }
754
755 static int __devexit mpc_dma_remove(struct platform_device *op)
756 {
757 struct device *dev = &op->dev;
758 struct mpc_dma *mdma = dev_get_drvdata(dev);
759
760 dma_async_device_unregister(&mdma->dma);
761 devm_free_irq(dev, mdma->irq, mdma);
762 irq_dispose_mapping(mdma->irq);
763
764 return 0;
765 }
766
767 static struct of_device_id mpc_dma_match[] = {
768 { .compatible = "fsl,mpc5121-dma", },
769 {},
770 };
771
772 static struct of_platform_driver mpc_dma_driver = {
773 .probe = mpc_dma_probe,
774 .remove = __devexit_p(mpc_dma_remove),
775 .driver = {
776 .name = DRV_NAME,
777 .owner = THIS_MODULE,
778 .of_match_table = mpc_dma_match,
779 },
780 };
781
782 static int __init mpc_dma_init(void)
783 {
784 return of_register_platform_driver(&mpc_dma_driver);
785 }
786 module_init(mpc_dma_init);
787
788 static void __exit mpc_dma_exit(void)
789 {
790 of_unregister_platform_driver(&mpc_dma_driver);
791 }
792 module_exit(mpc_dma_exit);
793
794 MODULE_LICENSE("GPL");
795 MODULE_AUTHOR("Piotr Ziecik <kosmo@semihalf.com>");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree