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Documentation: configfs examples crash fix
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / dma / mpc512x_dma.c
blobb9bae94f2015c99d095cf005d7e257cf3fcf607d
1 /*
2 * Copyright (C) Freescale Semicondutor, Inc. 2007, 2008.
3 * Copyright (C) Semihalf 2009
4 * Copyright (C) Ilya Yanok, Emcraft Systems 2010
5 *
6 * Written by Piotr Ziecik <kosmo@semihalf.com>. Hardware description
7 * (defines, structures and comments) was taken from MPC5121 DMA driver
8 * written by Hongjun Chen <hong-jun.chen@freescale.com>.
9 *
10 * Approved as OSADL project by a majority of OSADL members and funded
11 * by OSADL membership fees in 2009; for details see www.osadl.org.
12 *
13 * This program is free software; you can redistribute it and/or modify it
14 * under the terms of the GNU General Public License as published by the Free
15 * Software Foundation; either version 2 of the License, or (at your option)
16 * any later version.
17 *
18 * This program is distributed in the hope that it will be useful, but WITHOUT
19 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
20 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
21 * more details.
22 *
23 * You should have received a copy of the GNU General Public License along with
24 * this program; if not, write to the Free Software Foundation, Inc., 59
25 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 *
27 * The full GNU General Public License is included in this distribution in the
28 * file called COPYING.
29 */
30
31 /*
32 * This is initial version of MPC5121 DMA driver. Only memory to memory
33 * transfers are supported (tested using dmatest module).
34 */
35
36 #include <linux/module.h>
37 #include <linux/dmaengine.h>
38 #include <linux/dma-mapping.h>
39 #include <linux/interrupt.h>
40 #include <linux/io.h>
41 #include <linux/slab.h>
42 #include <linux/of_device.h>
43 #include <linux/of_platform.h>
44
45 #include <linux/random.h>
46
47 /* Number of DMA Transfer descriptors allocated per channel */
48 #define MPC_DMA_DESCRIPTORS 64
49
50 /* Macro definitions */
51 #define MPC_DMA_CHANNELS 64
52 #define MPC_DMA_TCD_OFFSET 0x1000
53
54 /* Arbitration mode of group and channel */
55 #define MPC_DMA_DMACR_EDCG (1 << 31)
56 #define MPC_DMA_DMACR_ERGA (1 << 3)
57 #define MPC_DMA_DMACR_ERCA (1 << 2)
58
59 /* Error codes */
60 #define MPC_DMA_DMAES_VLD (1 << 31)
61 #define MPC_DMA_DMAES_GPE (1 << 15)
62 #define MPC_DMA_DMAES_CPE (1 << 14)
63 #define MPC_DMA_DMAES_ERRCHN(err) \
64 (((err) >> 8) & 0x3f)
65 #define MPC_DMA_DMAES_SAE (1 << 7)
66 #define MPC_DMA_DMAES_SOE (1 << 6)
67 #define MPC_DMA_DMAES_DAE (1 << 5)
68 #define MPC_DMA_DMAES_DOE (1 << 4)
69 #define MPC_DMA_DMAES_NCE (1 << 3)
70 #define MPC_DMA_DMAES_SGE (1 << 2)
71 #define MPC_DMA_DMAES_SBE (1 << 1)
72 #define MPC_DMA_DMAES_DBE (1 << 0)
73
74 #define MPC_DMA_DMAGPOR_SNOOP_ENABLE (1 << 6)
75
76 #define MPC_DMA_TSIZE_1 0x00
77 #define MPC_DMA_TSIZE_2 0x01
78 #define MPC_DMA_TSIZE_4 0x02
79 #define MPC_DMA_TSIZE_16 0x04
80 #define MPC_DMA_TSIZE_32 0x05
81
82 /* MPC5121 DMA engine registers */
83 struct __attribute__ ((__packed__)) mpc_dma_regs {
84 /* 0x00 */
85 u32 dmacr; /* DMA control register */
86 u32 dmaes; /* DMA error status */
87 /* 0x08 */
88 u32 dmaerqh; /* DMA enable request high(channels 63~32) */
89 u32 dmaerql; /* DMA enable request low(channels 31~0) */
90 u32 dmaeeih; /* DMA enable error interrupt high(ch63~32) */
91 u32 dmaeeil; /* DMA enable error interrupt low(ch31~0) */
92 /* 0x18 */
93 u8 dmaserq; /* DMA set enable request */
94 u8 dmacerq; /* DMA clear enable request */
95 u8 dmaseei; /* DMA set enable error interrupt */
96 u8 dmaceei; /* DMA clear enable error interrupt */
97 /* 0x1c */
98 u8 dmacint; /* DMA clear interrupt request */
99 u8 dmacerr; /* DMA clear error */
100 u8 dmassrt; /* DMA set start bit */
101 u8 dmacdne; /* DMA clear DONE status bit */
102 /* 0x20 */
103 u32 dmainth; /* DMA interrupt request high(ch63~32) */
104 u32 dmaintl; /* DMA interrupt request low(ch31~0) */
105 u32 dmaerrh; /* DMA error high(ch63~32) */
106 u32 dmaerrl; /* DMA error low(ch31~0) */
107 /* 0x30 */
108 u32 dmahrsh; /* DMA hw request status high(ch63~32) */
109 u32 dmahrsl; /* DMA hardware request status low(ch31~0) */
110 union {
111 u32 dmaihsa; /* DMA interrupt high select AXE(ch63~32) */
112 u32 dmagpor; /* (General purpose register on MPC8308) */
113 };
114 u32 dmailsa; /* DMA interrupt low select AXE(ch31~0) */
115 /* 0x40 ~ 0xff */
116 u32 reserve0[48]; /* Reserved */
117 /* 0x100 */
118 u8 dchpri[MPC_DMA_CHANNELS];
119 /* DMA channels(0~63) priority */
120 };
121
122 struct __attribute__ ((__packed__)) mpc_dma_tcd {
123 /* 0x00 */
124 u32 saddr; /* Source address */
125
126 u32 smod:5; /* Source address modulo */
127 u32 ssize:3; /* Source data transfer size */
128 u32 dmod:5; /* Destination address modulo */
129 u32 dsize:3; /* Destination data transfer size */
130 u32 soff:16; /* Signed source address offset */
131
132 /* 0x08 */
133 u32 nbytes; /* Inner "minor" byte count */
134 u32 slast; /* Last source address adjustment */
135 u32 daddr; /* Destination address */
136
137 /* 0x14 */
138 u32 citer_elink:1; /* Enable channel-to-channel linking on
139 * minor loop complete
140 */
141 u32 citer_linkch:6; /* Link channel for minor loop complete */
142 u32 citer:9; /* Current "major" iteration count */
143 u32 doff:16; /* Signed destination address offset */
144
145 /* 0x18 */
146 u32 dlast_sga; /* Last Destination address adjustment/scatter
147 * gather address
148 */
149
150 /* 0x1c */
151 u32 biter_elink:1; /* Enable channel-to-channel linking on major
152 * loop complete
153 */
154 u32 biter_linkch:6;
155 u32 biter:9; /* Beginning "major" iteration count */
156 u32 bwc:2; /* Bandwidth control */
157 u32 major_linkch:6; /* Link channel number */
158 u32 done:1; /* Channel done */
159 u32 active:1; /* Channel active */
160 u32 major_elink:1; /* Enable channel-to-channel linking on major
161 * loop complete
162 */
163 u32 e_sg:1; /* Enable scatter/gather processing */
164 u32 d_req:1; /* Disable request */
165 u32 int_half:1; /* Enable an interrupt when major counter is
166 * half complete
167 */
168 u32 int_maj:1; /* Enable an interrupt when major iteration
169 * count completes
170 */
171 u32 start:1; /* Channel start */
172 };
173
174 struct mpc_dma_desc {
175 struct dma_async_tx_descriptor desc;
176 struct mpc_dma_tcd *tcd;
177 dma_addr_t tcd_paddr;
178 int error;
179 struct list_head node;
180 };
181
182 struct mpc_dma_chan {
183 struct dma_chan chan;
184 struct list_head free;
185 struct list_head prepared;
186 struct list_head queued;
187 struct list_head active;
188 struct list_head completed;
189 struct mpc_dma_tcd *tcd;
190 dma_addr_t tcd_paddr;
191 dma_cookie_t completed_cookie;
192
193 /* Lock for this structure */
194 spinlock_t lock;
195 };
196
197 struct mpc_dma {
198 struct dma_device dma;
199 struct tasklet_struct tasklet;
200 struct mpc_dma_chan channels[MPC_DMA_CHANNELS];
201 struct mpc_dma_regs __iomem *regs;
202 struct mpc_dma_tcd __iomem *tcd;
203 int irq;
204 int irq2;
205 uint error_status;
206 int is_mpc8308;
207
208 /* Lock for error_status field in this structure */
209 spinlock_t error_status_lock;
210 };
211
212 #define DRV_NAME "mpc512x_dma"
213
214 /* Convert struct dma_chan to struct mpc_dma_chan */
215 static inline struct mpc_dma_chan *dma_chan_to_mpc_dma_chan(struct dma_chan *c)
216 {
217 return container_of(c, struct mpc_dma_chan, chan);
218 }
219
220 /* Convert struct dma_chan to struct mpc_dma */
221 static inline struct mpc_dma *dma_chan_to_mpc_dma(struct dma_chan *c)
222 {
223 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(c);
224 return container_of(mchan, struct mpc_dma, channels[c->chan_id]);
225 }
226
227 /*
228 * Execute all queued DMA descriptors.
229 *
230 * Following requirements must be met while calling mpc_dma_execute():
231 * a) mchan->lock is acquired,
232 * b) mchan->active list is empty,
233 * c) mchan->queued list contains at least one entry.
234 */
235 static void mpc_dma_execute(struct mpc_dma_chan *mchan)
236 {
237 struct mpc_dma *mdma = dma_chan_to_mpc_dma(&mchan->chan);
238 struct mpc_dma_desc *first = NULL;
239 struct mpc_dma_desc *prev = NULL;
240 struct mpc_dma_desc *mdesc;
241 int cid = mchan->chan.chan_id;
242
243 /* Move all queued descriptors to active list */
244 list_splice_tail_init(&mchan->queued, &mchan->active);
245
246 /* Chain descriptors into one transaction */
247 list_for_each_entry(mdesc, &mchan->active, node) {
248 if (!first)
249 first = mdesc;
250
251 if (!prev) {
252 prev = mdesc;
253 continue;
254 }
255
256 prev->tcd->dlast_sga = mdesc->tcd_paddr;
257 prev->tcd->e_sg = 1;
258 mdesc->tcd->start = 1;
259
260 prev = mdesc;
261 }
262
263 prev->tcd->int_maj = 1;
264
265 /* Send first descriptor in chain into hardware */
266 memcpy_toio(&mdma->tcd[cid], first->tcd, sizeof(struct mpc_dma_tcd));
267
268 if (first != prev)
269 mdma->tcd[cid].e_sg = 1;
270 out_8(&mdma->regs->dmassrt, cid);
271 }
272
273 /* Handle interrupt on one half of DMA controller (32 channels) */
274 static void mpc_dma_irq_process(struct mpc_dma *mdma, u32 is, u32 es, int off)
275 {
276 struct mpc_dma_chan *mchan;
277 struct mpc_dma_desc *mdesc;
278 u32 status = is | es;
279 int ch;
280
281 while ((ch = fls(status) - 1) >= 0) {
282 status &= ~(1 << ch);
283 mchan = &mdma->channels[ch + off];
284
285 spin_lock(&mchan->lock);
286
287 out_8(&mdma->regs->dmacint, ch + off);
288 out_8(&mdma->regs->dmacerr, ch + off);
289
290 /* Check error status */
291 if (es & (1 << ch))
292 list_for_each_entry(mdesc, &mchan->active, node)
293 mdesc->error = -EIO;
294
295 /* Execute queued descriptors */
296 list_splice_tail_init(&mchan->active, &mchan->completed);
297 if (!list_empty(&mchan->queued))
298 mpc_dma_execute(mchan);
299
300 spin_unlock(&mchan->lock);
301 }
302 }
303
304 /* Interrupt handler */
305 static irqreturn_t mpc_dma_irq(int irq, void *data)
306 {
307 struct mpc_dma *mdma = data;
308 uint es;
309
310 /* Save error status register */
311 es = in_be32(&mdma->regs->dmaes);
312 spin_lock(&mdma->error_status_lock);
313 if ((es & MPC_DMA_DMAES_VLD) && mdma->error_status == 0)
314 mdma->error_status = es;
315 spin_unlock(&mdma->error_status_lock);
316
317 /* Handle interrupt on each channel */
318 if (mdma->dma.chancnt > 32) {
319 mpc_dma_irq_process(mdma, in_be32(&mdma->regs->dmainth),
320 in_be32(&mdma->regs->dmaerrh), 32);
321 }
322 mpc_dma_irq_process(mdma, in_be32(&mdma->regs->dmaintl),
323 in_be32(&mdma->regs->dmaerrl), 0);
324
325 /* Schedule tasklet */
326 tasklet_schedule(&mdma->tasklet);
327
328 return IRQ_HANDLED;
329 }
330
331 /* process completed descriptors */
332 static void mpc_dma_process_completed(struct mpc_dma *mdma)
333 {
334 dma_cookie_t last_cookie = 0;
335 struct mpc_dma_chan *mchan;
336 struct mpc_dma_desc *mdesc;
337 struct dma_async_tx_descriptor *desc;
338 unsigned long flags;
339 LIST_HEAD(list);
340 int i;
341
342 for (i = 0; i < mdma->dma.chancnt; i++) {
343 mchan = &mdma->channels[i];
344
345 /* Get all completed descriptors */
346 spin_lock_irqsave(&mchan->lock, flags);
347 if (!list_empty(&mchan->completed))
348 list_splice_tail_init(&mchan->completed, &list);
349 spin_unlock_irqrestore(&mchan->lock, flags);
350
351 if (list_empty(&list))
352 continue;
353
354 /* Execute callbacks and run dependencies */
355 list_for_each_entry(mdesc, &list, node) {
356 desc = &mdesc->desc;
357
358 if (desc->callback)
359 desc->callback(desc->callback_param);
360
361 last_cookie = desc->cookie;
362 dma_run_dependencies(desc);
363 }
364
365 /* Free descriptors */
366 spin_lock_irqsave(&mchan->lock, flags);
367 list_splice_tail_init(&list, &mchan->free);
368 mchan->completed_cookie = last_cookie;
369 spin_unlock_irqrestore(&mchan->lock, flags);
370 }
371 }
372
373 /* DMA Tasklet */
374 static void mpc_dma_tasklet(unsigned long data)
375 {
376 struct mpc_dma *mdma = (void *)data;
377 unsigned long flags;
378 uint es;
379
380 spin_lock_irqsave(&mdma->error_status_lock, flags);
381 es = mdma->error_status;
382 mdma->error_status = 0;
383 spin_unlock_irqrestore(&mdma->error_status_lock, flags);
384
385 /* Print nice error report */
386 if (es) {
387 dev_err(mdma->dma.dev,
388 "Hardware reported following error(s) on channel %u:\n",
389 MPC_DMA_DMAES_ERRCHN(es));
390
391 if (es & MPC_DMA_DMAES_GPE)
392 dev_err(mdma->dma.dev, "- Group Priority Error\n");
393 if (es & MPC_DMA_DMAES_CPE)
394 dev_err(mdma->dma.dev, "- Channel Priority Error\n");
395 if (es & MPC_DMA_DMAES_SAE)
396 dev_err(mdma->dma.dev, "- Source Address Error\n");
397 if (es & MPC_DMA_DMAES_SOE)
398 dev_err(mdma->dma.dev, "- Source Offset"
399 " Configuration Error\n");
400 if (es & MPC_DMA_DMAES_DAE)
401 dev_err(mdma->dma.dev, "- Destination Address"
402 " Error\n");
403 if (es & MPC_DMA_DMAES_DOE)
404 dev_err(mdma->dma.dev, "- Destination Offset"
405 " Configuration Error\n");
406 if (es & MPC_DMA_DMAES_NCE)
407 dev_err(mdma->dma.dev, "- NBytes/Citter"
408 " Configuration Error\n");
409 if (es & MPC_DMA_DMAES_SGE)
410 dev_err(mdma->dma.dev, "- Scatter/Gather"
411 " Configuration Error\n");
412 if (es & MPC_DMA_DMAES_SBE)
413 dev_err(mdma->dma.dev, "- Source Bus Error\n");
414 if (es & MPC_DMA_DMAES_DBE)
415 dev_err(mdma->dma.dev, "- Destination Bus Error\n");
416 }
417
418 mpc_dma_process_completed(mdma);
419 }
420
421 /* Submit descriptor to hardware */
422 static dma_cookie_t mpc_dma_tx_submit(struct dma_async_tx_descriptor *txd)
423 {
424 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(txd->chan);
425 struct mpc_dma_desc *mdesc;
426 unsigned long flags;
427 dma_cookie_t cookie;
428
429 mdesc = container_of(txd, struct mpc_dma_desc, desc);
430
431 spin_lock_irqsave(&mchan->lock, flags);
432
433 /* Move descriptor to queue */
434 list_move_tail(&mdesc->node, &mchan->queued);
435
436 /* If channel is idle, execute all queued descriptors */
437 if (list_empty(&mchan->active))
438 mpc_dma_execute(mchan);
439
440 /* Update cookie */
441 cookie = mchan->chan.cookie + 1;
442 if (cookie <= 0)
443 cookie = 1;
444
445 mchan->chan.cookie = cookie;
446 mdesc->desc.cookie = cookie;
447
448 spin_unlock_irqrestore(&mchan->lock, flags);
449
450 return cookie;
451 }
452
453 /* Alloc channel resources */
454 static int mpc_dma_alloc_chan_resources(struct dma_chan *chan)
455 {
456 struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan);
457 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
458 struct mpc_dma_desc *mdesc;
459 struct mpc_dma_tcd *tcd;
460 dma_addr_t tcd_paddr;
461 unsigned long flags;
462 LIST_HEAD(descs);
463 int i;
464
465 /* Alloc DMA memory for Transfer Control Descriptors */
466 tcd = dma_alloc_coherent(mdma->dma.dev,
467 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
468 &tcd_paddr, GFP_KERNEL);
469 if (!tcd)
470 return -ENOMEM;
471
472 /* Alloc descriptors for this channel */
473 for (i = 0; i < MPC_DMA_DESCRIPTORS; i++) {
474 mdesc = kzalloc(sizeof(struct mpc_dma_desc), GFP_KERNEL);
475 if (!mdesc) {
476 dev_notice(mdma->dma.dev, "Memory allocation error. "
477 "Allocated only %u descriptors\n", i);
478 break;
479 }
480
481 dma_async_tx_descriptor_init(&mdesc->desc, chan);
482 mdesc->desc.flags = DMA_CTRL_ACK;
483 mdesc->desc.tx_submit = mpc_dma_tx_submit;
484
485 mdesc->tcd = &tcd[i];
486 mdesc->tcd_paddr = tcd_paddr + (i * sizeof(struct mpc_dma_tcd));
487
488 list_add_tail(&mdesc->node, &descs);
489 }
490
491 /* Return error only if no descriptors were allocated */
492 if (i == 0) {
493 dma_free_coherent(mdma->dma.dev,
494 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
495 tcd, tcd_paddr);
496 return -ENOMEM;
497 }
498
499 spin_lock_irqsave(&mchan->lock, flags);
500 mchan->tcd = tcd;
501 mchan->tcd_paddr = tcd_paddr;
502 list_splice_tail_init(&descs, &mchan->free);
503 spin_unlock_irqrestore(&mchan->lock, flags);
504
505 /* Enable Error Interrupt */
506 out_8(&mdma->regs->dmaseei, chan->chan_id);
507
508 return 0;
509 }
510
511 /* Free channel resources */
512 static void mpc_dma_free_chan_resources(struct dma_chan *chan)
513 {
514 struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan);
515 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
516 struct mpc_dma_desc *mdesc, *tmp;
517 struct mpc_dma_tcd *tcd;
518 dma_addr_t tcd_paddr;
519 unsigned long flags;
520 LIST_HEAD(descs);
521
522 spin_lock_irqsave(&mchan->lock, flags);
523
524 /* Channel must be idle */
525 BUG_ON(!list_empty(&mchan->prepared));
526 BUG_ON(!list_empty(&mchan->queued));
527 BUG_ON(!list_empty(&mchan->active));
528 BUG_ON(!list_empty(&mchan->completed));
529
530 /* Move data */
531 list_splice_tail_init(&mchan->free, &descs);
532 tcd = mchan->tcd;
533 tcd_paddr = mchan->tcd_paddr;
534
535 spin_unlock_irqrestore(&mchan->lock, flags);
536
537 /* Free DMA memory used by descriptors */
538 dma_free_coherent(mdma->dma.dev,
539 MPC_DMA_DESCRIPTORS * sizeof(struct mpc_dma_tcd),
540 tcd, tcd_paddr);
541
542 /* Free descriptors */
543 list_for_each_entry_safe(mdesc, tmp, &descs, node)
544 kfree(mdesc);
545
546 /* Disable Error Interrupt */
547 out_8(&mdma->regs->dmaceei, chan->chan_id);
548 }
549
550 /* Send all pending descriptor to hardware */
551 static void mpc_dma_issue_pending(struct dma_chan *chan)
552 {
553 /*
554 * We are posting descriptors to the hardware as soon as
555 * they are ready, so this function does nothing.
556 */
557 }
558
559 /* Check request completion status */
560 static enum dma_status
561 mpc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
562 struct dma_tx_state *txstate)
563 {
564 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
565 unsigned long flags;
566 dma_cookie_t last_used;
567 dma_cookie_t last_complete;
568
569 spin_lock_irqsave(&mchan->lock, flags);
570 last_used = mchan->chan.cookie;
571 last_complete = mchan->completed_cookie;
572 spin_unlock_irqrestore(&mchan->lock, flags);
573
574 dma_set_tx_state(txstate, last_complete, last_used, 0);
575 return dma_async_is_complete(cookie, last_complete, last_used);
576 }
577
578 /* Prepare descriptor for memory to memory copy */
579 static struct dma_async_tx_descriptor *
580 mpc_dma_prep_memcpy(struct dma_chan *chan, dma_addr_t dst, dma_addr_t src,
581 size_t len, unsigned long flags)
582 {
583 struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan);
584 struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
585 struct mpc_dma_desc *mdesc = NULL;
586 struct mpc_dma_tcd *tcd;
587 unsigned long iflags;
588
589 /* Get free descriptor */
590 spin_lock_irqsave(&mchan->lock, iflags);
591 if (!list_empty(&mchan->free)) {
592 mdesc = list_first_entry(&mchan->free, struct mpc_dma_desc,
593 node);
594 list_del(&mdesc->node);
595 }
596 spin_unlock_irqrestore(&mchan->lock, iflags);
597
598 if (!mdesc) {
599 /* try to free completed descriptors */
600 mpc_dma_process_completed(mdma);
601 return NULL;
602 }
603
604 mdesc->error = 0;
605 tcd = mdesc->tcd;
606
607 /* Prepare Transfer Control Descriptor for this transaction */
608 memset(tcd, 0, sizeof(struct mpc_dma_tcd));
609
610 if (IS_ALIGNED(src | dst | len, 32)) {
611 tcd->ssize = MPC_DMA_TSIZE_32;
612 tcd->dsize = MPC_DMA_TSIZE_32;
613 tcd->soff = 32;
614 tcd->doff = 32;
615 } else if (!mdma->is_mpc8308 && IS_ALIGNED(src | dst | len, 16)) {
616 /* MPC8308 doesn't support 16 byte transfers */
617 tcd->ssize = MPC_DMA_TSIZE_16;
618 tcd->dsize = MPC_DMA_TSIZE_16;
619 tcd->soff = 16;
620 tcd->doff = 16;
621 } else if (IS_ALIGNED(src | dst | len, 4)) {
622 tcd->ssize = MPC_DMA_TSIZE_4;
623 tcd->dsize = MPC_DMA_TSIZE_4;
624 tcd->soff = 4;
625 tcd->doff = 4;
626 } else if (IS_ALIGNED(src | dst | len, 2)) {
627 tcd->ssize = MPC_DMA_TSIZE_2;
628 tcd->dsize = MPC_DMA_TSIZE_2;
629 tcd->soff = 2;
630 tcd->doff = 2;
631 } else {
632 tcd->ssize = MPC_DMA_TSIZE_1;
633 tcd->dsize = MPC_DMA_TSIZE_1;
634 tcd->soff = 1;
635 tcd->doff = 1;
636 }
637
638 tcd->saddr = src;
639 tcd->daddr = dst;
640 tcd->nbytes = len;
641 tcd->biter = 1;
642 tcd->citer = 1;
643
644 /* Place descriptor in prepared list */
645 spin_lock_irqsave(&mchan->lock, iflags);
646 list_add_tail(&mdesc->node, &mchan->prepared);
647 spin_unlock_irqrestore(&mchan->lock, iflags);
648
649 return &mdesc->desc;
650 }
651
652 static int __devinit mpc_dma_probe(struct platform_device *op)
653 {
654 struct device_node *dn = op->dev.of_node;
655 struct device *dev = &op->dev;
656 struct dma_device *dma;
657 struct mpc_dma *mdma;
658 struct mpc_dma_chan *mchan;
659 struct resource res;
660 ulong regs_start, regs_size;
661 int retval, i;
662
663 mdma = devm_kzalloc(dev, sizeof(struct mpc_dma), GFP_KERNEL);
664 if (!mdma) {
665 dev_err(dev, "Memory exhausted!\n");
666 return -ENOMEM;
667 }
668
669 mdma->irq = irq_of_parse_and_map(dn, 0);
670 if (mdma->irq == NO_IRQ) {
671 dev_err(dev, "Error mapping IRQ!\n");
672 return -EINVAL;
673 }
674
675 if (of_device_is_compatible(dn, "fsl,mpc8308-dma")) {
676 mdma->is_mpc8308 = 1;
677 mdma->irq2 = irq_of_parse_and_map(dn, 1);
678 if (mdma->irq2 == NO_IRQ) {
679 dev_err(dev, "Error mapping IRQ!\n");
680 return -EINVAL;
681 }
682 }
683
684 retval = of_address_to_resource(dn, 0, &res);
685 if (retval) {
686 dev_err(dev, "Error parsing memory region!\n");
687 return retval;
688 }
689
690 regs_start = res.start;
691 regs_size = resource_size(&res);
692
693 if (!devm_request_mem_region(dev, regs_start, regs_size, DRV_NAME)) {
694 dev_err(dev, "Error requesting memory region!\n");
695 return -EBUSY;
696 }
697
698 mdma->regs = devm_ioremap(dev, regs_start, regs_size);
699 if (!mdma->regs) {
700 dev_err(dev, "Error mapping memory region!\n");
701 return -ENOMEM;
702 }
703
704 mdma->tcd = (struct mpc_dma_tcd *)((u8 *)(mdma->regs)
705 + MPC_DMA_TCD_OFFSET);
706
707 retval = devm_request_irq(dev, mdma->irq, &mpc_dma_irq, 0, DRV_NAME,
708 mdma);
709 if (retval) {
710 dev_err(dev, "Error requesting IRQ!\n");
711 return -EINVAL;
712 }
713
714 if (mdma->is_mpc8308) {
715 retval = devm_request_irq(dev, mdma->irq2, &mpc_dma_irq, 0,
716 DRV_NAME, mdma);
717 if (retval) {
718 dev_err(dev, "Error requesting IRQ2!\n");
719 return -EINVAL;
720 }
721 }
722
723 spin_lock_init(&mdma->error_status_lock);
724
725 dma = &mdma->dma;
726 dma->dev = dev;
727 if (!mdma->is_mpc8308)
728 dma->chancnt = MPC_DMA_CHANNELS;
729 else
730 dma->chancnt = 16; /* MPC8308 DMA has only 16 channels */
731 dma->device_alloc_chan_resources = mpc_dma_alloc_chan_resources;
732 dma->device_free_chan_resources = mpc_dma_free_chan_resources;
733 dma->device_issue_pending = mpc_dma_issue_pending;
734 dma->device_tx_status = mpc_dma_tx_status;
735 dma->device_prep_dma_memcpy = mpc_dma_prep_memcpy;
736
737 INIT_LIST_HEAD(&dma->channels);
738 dma_cap_set(DMA_MEMCPY, dma->cap_mask);
739
740 for (i = 0; i < dma->chancnt; i++) {
741 mchan = &mdma->channels[i];
742
743 mchan->chan.device = dma;
744 mchan->chan.chan_id = i;
745 mchan->chan.cookie = 1;
746 mchan->completed_cookie = mchan->chan.cookie;
747
748 INIT_LIST_HEAD(&mchan->free);
749 INIT_LIST_HEAD(&mchan->prepared);
750 INIT_LIST_HEAD(&mchan->queued);
751 INIT_LIST_HEAD(&mchan->active);
752 INIT_LIST_HEAD(&mchan->completed);
753
754 spin_lock_init(&mchan->lock);
755 list_add_tail(&mchan->chan.device_node, &dma->channels);
756 }
757
758 tasklet_init(&mdma->tasklet, mpc_dma_tasklet, (unsigned long)mdma);
759
760 /*
761 * Configure DMA Engine:
762 * - Dynamic clock,
763 * - Round-robin group arbitration,
764 * - Round-robin channel arbitration.
765 */
766 if (!mdma->is_mpc8308) {
767 out_be32(&mdma->regs->dmacr, MPC_DMA_DMACR_EDCG |
768 MPC_DMA_DMACR_ERGA | MPC_DMA_DMACR_ERCA);
769
770 /* Disable hardware DMA requests */
771 out_be32(&mdma->regs->dmaerqh, 0);
772 out_be32(&mdma->regs->dmaerql, 0);
773
774 /* Disable error interrupts */
775 out_be32(&mdma->regs->dmaeeih, 0);
776 out_be32(&mdma->regs->dmaeeil, 0);
777
778 /* Clear interrupts status */
779 out_be32(&mdma->regs->dmainth, 0xFFFFFFFF);
780 out_be32(&mdma->regs->dmaintl, 0xFFFFFFFF);
781 out_be32(&mdma->regs->dmaerrh, 0xFFFFFFFF);
782 out_be32(&mdma->regs->dmaerrl, 0xFFFFFFFF);
783
784 /* Route interrupts to IPIC */
785 out_be32(&mdma->regs->dmaihsa, 0);
786 out_be32(&mdma->regs->dmailsa, 0);
787 } else {
788 /* MPC8308 has 16 channels and lacks some registers */
789 out_be32(&mdma->regs->dmacr, MPC_DMA_DMACR_ERCA);
790
791 /* enable snooping */
792 out_be32(&mdma->regs->dmagpor, MPC_DMA_DMAGPOR_SNOOP_ENABLE);
793 /* Disable error interrupts */
794 out_be32(&mdma->regs->dmaeeil, 0);
795
796 /* Clear interrupts status */
797 out_be32(&mdma->regs->dmaintl, 0xFFFF);
798 out_be32(&mdma->regs->dmaerrl, 0xFFFF);
799 }
800
801 /* Register DMA engine */
802 dev_set_drvdata(dev, mdma);
803 retval = dma_async_device_register(dma);
804 if (retval) {
805 devm_free_irq(dev, mdma->irq, mdma);
806 irq_dispose_mapping(mdma->irq);
807 }
808
809 return retval;
810 }
811
812 static int __devexit mpc_dma_remove(struct platform_device *op)
813 {
814 struct device *dev = &op->dev;
815 struct mpc_dma *mdma = dev_get_drvdata(dev);
816
817 dma_async_device_unregister(&mdma->dma);
818 devm_free_irq(dev, mdma->irq, mdma);
819 irq_dispose_mapping(mdma->irq);
820
821 return 0;
822 }
823
824 static struct of_device_id mpc_dma_match[] = {
825 { .compatible = "fsl,mpc5121-dma", },
826 {},
827 };
828
829 static struct platform_driver mpc_dma_driver = {
830 .probe = mpc_dma_probe,
831 .remove = __devexit_p(mpc_dma_remove),
832 .driver = {
833 .name = DRV_NAME,
834 .owner = THIS_MODULE,
835 .of_match_table = mpc_dma_match,
836 },
837 };
838
839 static int __init mpc_dma_init(void)
840 {
841 return platform_driver_register(&mpc_dma_driver);
842 }
843 module_init(mpc_dma_init);
844
845 static void __exit mpc_dma_exit(void)
846 {
847 platform_driver_unregister(&mpc_dma_driver);
848 }
849 module_exit(mpc_dma_exit);
850
851 MODULE_LICENSE("GPL");
852 MODULE_AUTHOR("Piotr Ziecik <kosmo@semihalf.com>");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree