xref: /openbmc/linux/drivers/dma/txx9dmac.c (revision 151f4e2b)
1 /*
2  * Driver for the TXx9 SoC DMA Controller
3  *
4  * Copyright (C) 2009 Atsushi Nemoto
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #include <linux/dma-mapping.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 #include <linux/scatterlist.h>
18 
19 #include "dmaengine.h"
20 #include "txx9dmac.h"
21 
22 static struct txx9dmac_chan *to_txx9dmac_chan(struct dma_chan *chan)
23 {
24 	return container_of(chan, struct txx9dmac_chan, chan);
25 }
26 
27 static struct txx9dmac_cregs __iomem *__dma_regs(const struct txx9dmac_chan *dc)
28 {
29 	return dc->ch_regs;
30 }
31 
32 static struct txx9dmac_cregs32 __iomem *__dma_regs32(
33 	const struct txx9dmac_chan *dc)
34 {
35 	return dc->ch_regs;
36 }
37 
38 #define channel64_readq(dc, name) \
39 	__raw_readq(&(__dma_regs(dc)->name))
40 #define channel64_writeq(dc, name, val) \
41 	__raw_writeq((val), &(__dma_regs(dc)->name))
42 #define channel64_readl(dc, name) \
43 	__raw_readl(&(__dma_regs(dc)->name))
44 #define channel64_writel(dc, name, val) \
45 	__raw_writel((val), &(__dma_regs(dc)->name))
46 
47 #define channel32_readl(dc, name) \
48 	__raw_readl(&(__dma_regs32(dc)->name))
49 #define channel32_writel(dc, name, val) \
50 	__raw_writel((val), &(__dma_regs32(dc)->name))
51 
52 #define channel_readq(dc, name) channel64_readq(dc, name)
53 #define channel_writeq(dc, name, val) channel64_writeq(dc, name, val)
54 #define channel_readl(dc, name) \
55 	(is_dmac64(dc) ? \
56 	 channel64_readl(dc, name) : channel32_readl(dc, name))
57 #define channel_writel(dc, name, val) \
58 	(is_dmac64(dc) ? \
59 	 channel64_writel(dc, name, val) : channel32_writel(dc, name, val))
60 
61 static dma_addr_t channel64_read_CHAR(const struct txx9dmac_chan *dc)
62 {
63 	if (sizeof(__dma_regs(dc)->CHAR) == sizeof(u64))
64 		return channel64_readq(dc, CHAR);
65 	else
66 		return channel64_readl(dc, CHAR);
67 }
68 
69 static void channel64_write_CHAR(const struct txx9dmac_chan *dc, dma_addr_t val)
70 {
71 	if (sizeof(__dma_regs(dc)->CHAR) == sizeof(u64))
72 		channel64_writeq(dc, CHAR, val);
73 	else
74 		channel64_writel(dc, CHAR, val);
75 }
76 
77 static void channel64_clear_CHAR(const struct txx9dmac_chan *dc)
78 {
79 #if defined(CONFIG_32BIT) && !defined(CONFIG_PHYS_ADDR_T_64BIT)
80 	channel64_writel(dc, CHAR, 0);
81 	channel64_writel(dc, __pad_CHAR, 0);
82 #else
83 	channel64_writeq(dc, CHAR, 0);
84 #endif
85 }
86 
87 static dma_addr_t channel_read_CHAR(const struct txx9dmac_chan *dc)
88 {
89 	if (is_dmac64(dc))
90 		return channel64_read_CHAR(dc);
91 	else
92 		return channel32_readl(dc, CHAR);
93 }
94 
95 static void channel_write_CHAR(const struct txx9dmac_chan *dc, dma_addr_t val)
96 {
97 	if (is_dmac64(dc))
98 		channel64_write_CHAR(dc, val);
99 	else
100 		channel32_writel(dc, CHAR, val);
101 }
102 
103 static struct txx9dmac_regs __iomem *__txx9dmac_regs(
104 	const struct txx9dmac_dev *ddev)
105 {
106 	return ddev->regs;
107 }
108 
109 static struct txx9dmac_regs32 __iomem *__txx9dmac_regs32(
110 	const struct txx9dmac_dev *ddev)
111 {
112 	return ddev->regs;
113 }
114 
115 #define dma64_readl(ddev, name) \
116 	__raw_readl(&(__txx9dmac_regs(ddev)->name))
117 #define dma64_writel(ddev, name, val) \
118 	__raw_writel((val), &(__txx9dmac_regs(ddev)->name))
119 
120 #define dma32_readl(ddev, name) \
121 	__raw_readl(&(__txx9dmac_regs32(ddev)->name))
122 #define dma32_writel(ddev, name, val) \
123 	__raw_writel((val), &(__txx9dmac_regs32(ddev)->name))
124 
125 #define dma_readl(ddev, name) \
126 	(__is_dmac64(ddev) ? \
127 	dma64_readl(ddev, name) : dma32_readl(ddev, name))
128 #define dma_writel(ddev, name, val) \
129 	(__is_dmac64(ddev) ? \
130 	dma64_writel(ddev, name, val) : dma32_writel(ddev, name, val))
131 
132 static struct device *chan2dev(struct dma_chan *chan)
133 {
134 	return &chan->dev->device;
135 }
136 static struct device *chan2parent(struct dma_chan *chan)
137 {
138 	return chan->dev->device.parent;
139 }
140 
141 static struct txx9dmac_desc *
142 txd_to_txx9dmac_desc(struct dma_async_tx_descriptor *txd)
143 {
144 	return container_of(txd, struct txx9dmac_desc, txd);
145 }
146 
147 static dma_addr_t desc_read_CHAR(const struct txx9dmac_chan *dc,
148 				 const struct txx9dmac_desc *desc)
149 {
150 	return is_dmac64(dc) ? desc->hwdesc.CHAR : desc->hwdesc32.CHAR;
151 }
152 
153 static void desc_write_CHAR(const struct txx9dmac_chan *dc,
154 			    struct txx9dmac_desc *desc, dma_addr_t val)
155 {
156 	if (is_dmac64(dc))
157 		desc->hwdesc.CHAR = val;
158 	else
159 		desc->hwdesc32.CHAR = val;
160 }
161 
162 #define TXX9_DMA_MAX_COUNT	0x04000000
163 
164 #define TXX9_DMA_INITIAL_DESC_COUNT	64
165 
166 static struct txx9dmac_desc *txx9dmac_first_active(struct txx9dmac_chan *dc)
167 {
168 	return list_entry(dc->active_list.next,
169 			  struct txx9dmac_desc, desc_node);
170 }
171 
172 static struct txx9dmac_desc *txx9dmac_last_active(struct txx9dmac_chan *dc)
173 {
174 	return list_entry(dc->active_list.prev,
175 			  struct txx9dmac_desc, desc_node);
176 }
177 
178 static struct txx9dmac_desc *txx9dmac_first_queued(struct txx9dmac_chan *dc)
179 {
180 	return list_entry(dc->queue.next, struct txx9dmac_desc, desc_node);
181 }
182 
183 static struct txx9dmac_desc *txx9dmac_last_child(struct txx9dmac_desc *desc)
184 {
185 	if (!list_empty(&desc->tx_list))
186 		desc = list_entry(desc->tx_list.prev, typeof(*desc), desc_node);
187 	return desc;
188 }
189 
190 static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx);
191 
192 static struct txx9dmac_desc *txx9dmac_desc_alloc(struct txx9dmac_chan *dc,
193 						 gfp_t flags)
194 {
195 	struct txx9dmac_dev *ddev = dc->ddev;
196 	struct txx9dmac_desc *desc;
197 
198 	desc = kzalloc(sizeof(*desc), flags);
199 	if (!desc)
200 		return NULL;
201 	INIT_LIST_HEAD(&desc->tx_list);
202 	dma_async_tx_descriptor_init(&desc->txd, &dc->chan);
203 	desc->txd.tx_submit = txx9dmac_tx_submit;
204 	/* txd.flags will be overwritten in prep funcs */
205 	desc->txd.flags = DMA_CTRL_ACK;
206 	desc->txd.phys = dma_map_single(chan2parent(&dc->chan), &desc->hwdesc,
207 					ddev->descsize, DMA_TO_DEVICE);
208 	return desc;
209 }
210 
211 static struct txx9dmac_desc *txx9dmac_desc_get(struct txx9dmac_chan *dc)
212 {
213 	struct txx9dmac_desc *desc, *_desc;
214 	struct txx9dmac_desc *ret = NULL;
215 	unsigned int i = 0;
216 
217 	spin_lock_bh(&dc->lock);
218 	list_for_each_entry_safe(desc, _desc, &dc->free_list, desc_node) {
219 		if (async_tx_test_ack(&desc->txd)) {
220 			list_del(&desc->desc_node);
221 			ret = desc;
222 			break;
223 		}
224 		dev_dbg(chan2dev(&dc->chan), "desc %p not ACKed\n", desc);
225 		i++;
226 	}
227 	spin_unlock_bh(&dc->lock);
228 
229 	dev_vdbg(chan2dev(&dc->chan), "scanned %u descriptors on freelist\n",
230 		 i);
231 	if (!ret) {
232 		ret = txx9dmac_desc_alloc(dc, GFP_ATOMIC);
233 		if (ret) {
234 			spin_lock_bh(&dc->lock);
235 			dc->descs_allocated++;
236 			spin_unlock_bh(&dc->lock);
237 		} else
238 			dev_err(chan2dev(&dc->chan),
239 				"not enough descriptors available\n");
240 	}
241 	return ret;
242 }
243 
244 static void txx9dmac_sync_desc_for_cpu(struct txx9dmac_chan *dc,
245 				       struct txx9dmac_desc *desc)
246 {
247 	struct txx9dmac_dev *ddev = dc->ddev;
248 	struct txx9dmac_desc *child;
249 
250 	list_for_each_entry(child, &desc->tx_list, desc_node)
251 		dma_sync_single_for_cpu(chan2parent(&dc->chan),
252 				child->txd.phys, ddev->descsize,
253 				DMA_TO_DEVICE);
254 	dma_sync_single_for_cpu(chan2parent(&dc->chan),
255 			desc->txd.phys, ddev->descsize,
256 			DMA_TO_DEVICE);
257 }
258 
259 /*
260  * Move a descriptor, including any children, to the free list.
261  * `desc' must not be on any lists.
262  */
263 static void txx9dmac_desc_put(struct txx9dmac_chan *dc,
264 			      struct txx9dmac_desc *desc)
265 {
266 	if (desc) {
267 		struct txx9dmac_desc *child;
268 
269 		txx9dmac_sync_desc_for_cpu(dc, desc);
270 
271 		spin_lock_bh(&dc->lock);
272 		list_for_each_entry(child, &desc->tx_list, desc_node)
273 			dev_vdbg(chan2dev(&dc->chan),
274 				 "moving child desc %p to freelist\n",
275 				 child);
276 		list_splice_init(&desc->tx_list, &dc->free_list);
277 		dev_vdbg(chan2dev(&dc->chan), "moving desc %p to freelist\n",
278 			 desc);
279 		list_add(&desc->desc_node, &dc->free_list);
280 		spin_unlock_bh(&dc->lock);
281 	}
282 }
283 
284 /*----------------------------------------------------------------------*/
285 
286 static void txx9dmac_dump_regs(struct txx9dmac_chan *dc)
287 {
288 	if (is_dmac64(dc))
289 		dev_err(chan2dev(&dc->chan),
290 			"  CHAR: %#llx SAR: %#llx DAR: %#llx CNTR: %#x"
291 			" SAIR: %#x DAIR: %#x CCR: %#x CSR: %#x\n",
292 			(u64)channel64_read_CHAR(dc),
293 			channel64_readq(dc, SAR),
294 			channel64_readq(dc, DAR),
295 			channel64_readl(dc, CNTR),
296 			channel64_readl(dc, SAIR),
297 			channel64_readl(dc, DAIR),
298 			channel64_readl(dc, CCR),
299 			channel64_readl(dc, CSR));
300 	else
301 		dev_err(chan2dev(&dc->chan),
302 			"  CHAR: %#x SAR: %#x DAR: %#x CNTR: %#x"
303 			" SAIR: %#x DAIR: %#x CCR: %#x CSR: %#x\n",
304 			channel32_readl(dc, CHAR),
305 			channel32_readl(dc, SAR),
306 			channel32_readl(dc, DAR),
307 			channel32_readl(dc, CNTR),
308 			channel32_readl(dc, SAIR),
309 			channel32_readl(dc, DAIR),
310 			channel32_readl(dc, CCR),
311 			channel32_readl(dc, CSR));
312 }
313 
314 static void txx9dmac_reset_chan(struct txx9dmac_chan *dc)
315 {
316 	channel_writel(dc, CCR, TXX9_DMA_CCR_CHRST);
317 	if (is_dmac64(dc)) {
318 		channel64_clear_CHAR(dc);
319 		channel_writeq(dc, SAR, 0);
320 		channel_writeq(dc, DAR, 0);
321 	} else {
322 		channel_writel(dc, CHAR, 0);
323 		channel_writel(dc, SAR, 0);
324 		channel_writel(dc, DAR, 0);
325 	}
326 	channel_writel(dc, CNTR, 0);
327 	channel_writel(dc, SAIR, 0);
328 	channel_writel(dc, DAIR, 0);
329 	channel_writel(dc, CCR, 0);
330 }
331 
332 /* Called with dc->lock held and bh disabled */
333 static void txx9dmac_dostart(struct txx9dmac_chan *dc,
334 			     struct txx9dmac_desc *first)
335 {
336 	struct txx9dmac_slave *ds = dc->chan.private;
337 	u32 sai, dai;
338 
339 	dev_vdbg(chan2dev(&dc->chan), "dostart %u %p\n",
340 		 first->txd.cookie, first);
341 	/* ASSERT:  channel is idle */
342 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
343 		dev_err(chan2dev(&dc->chan),
344 			"BUG: Attempted to start non-idle channel\n");
345 		txx9dmac_dump_regs(dc);
346 		/* The tasklet will hopefully advance the queue... */
347 		return;
348 	}
349 
350 	if (is_dmac64(dc)) {
351 		channel64_writel(dc, CNTR, 0);
352 		channel64_writel(dc, CSR, 0xffffffff);
353 		if (ds) {
354 			if (ds->tx_reg) {
355 				sai = ds->reg_width;
356 				dai = 0;
357 			} else {
358 				sai = 0;
359 				dai = ds->reg_width;
360 			}
361 		} else {
362 			sai = 8;
363 			dai = 8;
364 		}
365 		channel64_writel(dc, SAIR, sai);
366 		channel64_writel(dc, DAIR, dai);
367 		/* All 64-bit DMAC supports SMPCHN */
368 		channel64_writel(dc, CCR, dc->ccr);
369 		/* Writing a non zero value to CHAR will assert XFACT */
370 		channel64_write_CHAR(dc, first->txd.phys);
371 	} else {
372 		channel32_writel(dc, CNTR, 0);
373 		channel32_writel(dc, CSR, 0xffffffff);
374 		if (ds) {
375 			if (ds->tx_reg) {
376 				sai = ds->reg_width;
377 				dai = 0;
378 			} else {
379 				sai = 0;
380 				dai = ds->reg_width;
381 			}
382 		} else {
383 			sai = 4;
384 			dai = 4;
385 		}
386 		channel32_writel(dc, SAIR, sai);
387 		channel32_writel(dc, DAIR, dai);
388 		if (txx9_dma_have_SMPCHN()) {
389 			channel32_writel(dc, CCR, dc->ccr);
390 			/* Writing a non zero value to CHAR will assert XFACT */
391 			channel32_writel(dc, CHAR, first->txd.phys);
392 		} else {
393 			channel32_writel(dc, CHAR, first->txd.phys);
394 			channel32_writel(dc, CCR, dc->ccr);
395 		}
396 	}
397 }
398 
399 /*----------------------------------------------------------------------*/
400 
401 static void
402 txx9dmac_descriptor_complete(struct txx9dmac_chan *dc,
403 			     struct txx9dmac_desc *desc)
404 {
405 	struct dmaengine_desc_callback cb;
406 	struct dma_async_tx_descriptor *txd = &desc->txd;
407 
408 	dev_vdbg(chan2dev(&dc->chan), "descriptor %u %p complete\n",
409 		 txd->cookie, desc);
410 
411 	dma_cookie_complete(txd);
412 	dmaengine_desc_get_callback(txd, &cb);
413 
414 	txx9dmac_sync_desc_for_cpu(dc, desc);
415 	list_splice_init(&desc->tx_list, &dc->free_list);
416 	list_move(&desc->desc_node, &dc->free_list);
417 
418 	dma_descriptor_unmap(txd);
419 	/*
420 	 * The API requires that no submissions are done from a
421 	 * callback, so we don't need to drop the lock here
422 	 */
423 	dmaengine_desc_callback_invoke(&cb, NULL);
424 	dma_run_dependencies(txd);
425 }
426 
427 static void txx9dmac_dequeue(struct txx9dmac_chan *dc, struct list_head *list)
428 {
429 	struct txx9dmac_dev *ddev = dc->ddev;
430 	struct txx9dmac_desc *desc;
431 	struct txx9dmac_desc *prev = NULL;
432 
433 	BUG_ON(!list_empty(list));
434 	do {
435 		desc = txx9dmac_first_queued(dc);
436 		if (prev) {
437 			desc_write_CHAR(dc, prev, desc->txd.phys);
438 			dma_sync_single_for_device(chan2parent(&dc->chan),
439 				prev->txd.phys, ddev->descsize,
440 				DMA_TO_DEVICE);
441 		}
442 		prev = txx9dmac_last_child(desc);
443 		list_move_tail(&desc->desc_node, list);
444 		/* Make chain-completion interrupt happen */
445 		if ((desc->txd.flags & DMA_PREP_INTERRUPT) &&
446 		    !txx9dmac_chan_INTENT(dc))
447 			break;
448 	} while (!list_empty(&dc->queue));
449 }
450 
451 static void txx9dmac_complete_all(struct txx9dmac_chan *dc)
452 {
453 	struct txx9dmac_desc *desc, *_desc;
454 	LIST_HEAD(list);
455 
456 	/*
457 	 * Submit queued descriptors ASAP, i.e. before we go through
458 	 * the completed ones.
459 	 */
460 	list_splice_init(&dc->active_list, &list);
461 	if (!list_empty(&dc->queue)) {
462 		txx9dmac_dequeue(dc, &dc->active_list);
463 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
464 	}
465 
466 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
467 		txx9dmac_descriptor_complete(dc, desc);
468 }
469 
470 static void txx9dmac_dump_desc(struct txx9dmac_chan *dc,
471 			       struct txx9dmac_hwdesc *desc)
472 {
473 	if (is_dmac64(dc)) {
474 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
475 		dev_crit(chan2dev(&dc->chan),
476 			 "  desc: ch%#llx s%#llx d%#llx c%#x\n",
477 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR);
478 #else
479 		dev_crit(chan2dev(&dc->chan),
480 			 "  desc: ch%#llx s%#llx d%#llx c%#x"
481 			 " si%#x di%#x cc%#x cs%#x\n",
482 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR,
483 			 desc->SAIR, desc->DAIR, desc->CCR, desc->CSR);
484 #endif
485 	} else {
486 		struct txx9dmac_hwdesc32 *d = (struct txx9dmac_hwdesc32 *)desc;
487 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
488 		dev_crit(chan2dev(&dc->chan),
489 			 "  desc: ch%#x s%#x d%#x c%#x\n",
490 			 d->CHAR, d->SAR, d->DAR, d->CNTR);
491 #else
492 		dev_crit(chan2dev(&dc->chan),
493 			 "  desc: ch%#x s%#x d%#x c%#x"
494 			 " si%#x di%#x cc%#x cs%#x\n",
495 			 d->CHAR, d->SAR, d->DAR, d->CNTR,
496 			 d->SAIR, d->DAIR, d->CCR, d->CSR);
497 #endif
498 	}
499 }
500 
501 static void txx9dmac_handle_error(struct txx9dmac_chan *dc, u32 csr)
502 {
503 	struct txx9dmac_desc *bad_desc;
504 	struct txx9dmac_desc *child;
505 	u32 errors;
506 
507 	/*
508 	 * The descriptor currently at the head of the active list is
509 	 * borked. Since we don't have any way to report errors, we'll
510 	 * just have to scream loudly and try to carry on.
511 	 */
512 	dev_crit(chan2dev(&dc->chan), "Abnormal Chain Completion\n");
513 	txx9dmac_dump_regs(dc);
514 
515 	bad_desc = txx9dmac_first_active(dc);
516 	list_del_init(&bad_desc->desc_node);
517 
518 	/* Clear all error flags and try to restart the controller */
519 	errors = csr & (TXX9_DMA_CSR_ABCHC |
520 			TXX9_DMA_CSR_CFERR | TXX9_DMA_CSR_CHERR |
521 			TXX9_DMA_CSR_DESERR | TXX9_DMA_CSR_SORERR);
522 	channel_writel(dc, CSR, errors);
523 
524 	if (list_empty(&dc->active_list) && !list_empty(&dc->queue))
525 		txx9dmac_dequeue(dc, &dc->active_list);
526 	if (!list_empty(&dc->active_list))
527 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
528 
529 	dev_crit(chan2dev(&dc->chan),
530 		 "Bad descriptor submitted for DMA! (cookie: %d)\n",
531 		 bad_desc->txd.cookie);
532 	txx9dmac_dump_desc(dc, &bad_desc->hwdesc);
533 	list_for_each_entry(child, &bad_desc->tx_list, desc_node)
534 		txx9dmac_dump_desc(dc, &child->hwdesc);
535 	/* Pretend the descriptor completed successfully */
536 	txx9dmac_descriptor_complete(dc, bad_desc);
537 }
538 
539 static void txx9dmac_scan_descriptors(struct txx9dmac_chan *dc)
540 {
541 	dma_addr_t chain;
542 	struct txx9dmac_desc *desc, *_desc;
543 	struct txx9dmac_desc *child;
544 	u32 csr;
545 
546 	if (is_dmac64(dc)) {
547 		chain = channel64_read_CHAR(dc);
548 		csr = channel64_readl(dc, CSR);
549 		channel64_writel(dc, CSR, csr);
550 	} else {
551 		chain = channel32_readl(dc, CHAR);
552 		csr = channel32_readl(dc, CSR);
553 		channel32_writel(dc, CSR, csr);
554 	}
555 	/* For dynamic chain, we should look at XFACT instead of NCHNC */
556 	if (!(csr & (TXX9_DMA_CSR_XFACT | TXX9_DMA_CSR_ABCHC))) {
557 		/* Everything we've submitted is done */
558 		txx9dmac_complete_all(dc);
559 		return;
560 	}
561 	if (!(csr & TXX9_DMA_CSR_CHNEN))
562 		chain = 0;	/* last descriptor of this chain */
563 
564 	dev_vdbg(chan2dev(&dc->chan), "scan_descriptors: char=%#llx\n",
565 		 (u64)chain);
566 
567 	list_for_each_entry_safe(desc, _desc, &dc->active_list, desc_node) {
568 		if (desc_read_CHAR(dc, desc) == chain) {
569 			/* This one is currently in progress */
570 			if (csr & TXX9_DMA_CSR_ABCHC)
571 				goto scan_done;
572 			return;
573 		}
574 
575 		list_for_each_entry(child, &desc->tx_list, desc_node)
576 			if (desc_read_CHAR(dc, child) == chain) {
577 				/* Currently in progress */
578 				if (csr & TXX9_DMA_CSR_ABCHC)
579 					goto scan_done;
580 				return;
581 			}
582 
583 		/*
584 		 * No descriptors so far seem to be in progress, i.e.
585 		 * this one must be done.
586 		 */
587 		txx9dmac_descriptor_complete(dc, desc);
588 	}
589 scan_done:
590 	if (csr & TXX9_DMA_CSR_ABCHC) {
591 		txx9dmac_handle_error(dc, csr);
592 		return;
593 	}
594 
595 	dev_err(chan2dev(&dc->chan),
596 		"BUG: All descriptors done, but channel not idle!\n");
597 
598 	/* Try to continue after resetting the channel... */
599 	txx9dmac_reset_chan(dc);
600 
601 	if (!list_empty(&dc->queue)) {
602 		txx9dmac_dequeue(dc, &dc->active_list);
603 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
604 	}
605 }
606 
607 static void txx9dmac_chan_tasklet(unsigned long data)
608 {
609 	int irq;
610 	u32 csr;
611 	struct txx9dmac_chan *dc;
612 
613 	dc = (struct txx9dmac_chan *)data;
614 	csr = channel_readl(dc, CSR);
615 	dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n", csr);
616 
617 	spin_lock(&dc->lock);
618 	if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
619 		   TXX9_DMA_CSR_NTRNFC))
620 		txx9dmac_scan_descriptors(dc);
621 	spin_unlock(&dc->lock);
622 	irq = dc->irq;
623 
624 	enable_irq(irq);
625 }
626 
627 static irqreturn_t txx9dmac_chan_interrupt(int irq, void *dev_id)
628 {
629 	struct txx9dmac_chan *dc = dev_id;
630 
631 	dev_vdbg(chan2dev(&dc->chan), "interrupt: status=%#x\n",
632 			channel_readl(dc, CSR));
633 
634 	tasklet_schedule(&dc->tasklet);
635 	/*
636 	 * Just disable the interrupts. We'll turn them back on in the
637 	 * softirq handler.
638 	 */
639 	disable_irq_nosync(irq);
640 
641 	return IRQ_HANDLED;
642 }
643 
644 static void txx9dmac_tasklet(unsigned long data)
645 {
646 	int irq;
647 	u32 csr;
648 	struct txx9dmac_chan *dc;
649 
650 	struct txx9dmac_dev *ddev = (struct txx9dmac_dev *)data;
651 	u32 mcr;
652 	int i;
653 
654 	mcr = dma_readl(ddev, MCR);
655 	dev_vdbg(ddev->chan[0]->dma.dev, "tasklet: mcr=%x\n", mcr);
656 	for (i = 0; i < TXX9_DMA_MAX_NR_CHANNELS; i++) {
657 		if ((mcr >> (24 + i)) & 0x11) {
658 			dc = ddev->chan[i];
659 			csr = channel_readl(dc, CSR);
660 			dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n",
661 				 csr);
662 			spin_lock(&dc->lock);
663 			if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
664 				   TXX9_DMA_CSR_NTRNFC))
665 				txx9dmac_scan_descriptors(dc);
666 			spin_unlock(&dc->lock);
667 		}
668 	}
669 	irq = ddev->irq;
670 
671 	enable_irq(irq);
672 }
673 
674 static irqreturn_t txx9dmac_interrupt(int irq, void *dev_id)
675 {
676 	struct txx9dmac_dev *ddev = dev_id;
677 
678 	dev_vdbg(ddev->chan[0]->dma.dev, "interrupt: status=%#x\n",
679 			dma_readl(ddev, MCR));
680 
681 	tasklet_schedule(&ddev->tasklet);
682 	/*
683 	 * Just disable the interrupts. We'll turn them back on in the
684 	 * softirq handler.
685 	 */
686 	disable_irq_nosync(irq);
687 
688 	return IRQ_HANDLED;
689 }
690 
691 /*----------------------------------------------------------------------*/
692 
693 static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx)
694 {
695 	struct txx9dmac_desc *desc = txd_to_txx9dmac_desc(tx);
696 	struct txx9dmac_chan *dc = to_txx9dmac_chan(tx->chan);
697 	dma_cookie_t cookie;
698 
699 	spin_lock_bh(&dc->lock);
700 	cookie = dma_cookie_assign(tx);
701 
702 	dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u %p\n",
703 		 desc->txd.cookie, desc);
704 
705 	list_add_tail(&desc->desc_node, &dc->queue);
706 	spin_unlock_bh(&dc->lock);
707 
708 	return cookie;
709 }
710 
711 static struct dma_async_tx_descriptor *
712 txx9dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
713 		size_t len, unsigned long flags)
714 {
715 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
716 	struct txx9dmac_dev *ddev = dc->ddev;
717 	struct txx9dmac_desc *desc;
718 	struct txx9dmac_desc *first;
719 	struct txx9dmac_desc *prev;
720 	size_t xfer_count;
721 	size_t offset;
722 
723 	dev_vdbg(chan2dev(chan), "prep_dma_memcpy d%#llx s%#llx l%#zx f%#lx\n",
724 		 (u64)dest, (u64)src, len, flags);
725 
726 	if (unlikely(!len)) {
727 		dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n");
728 		return NULL;
729 	}
730 
731 	prev = first = NULL;
732 
733 	for (offset = 0; offset < len; offset += xfer_count) {
734 		xfer_count = min_t(size_t, len - offset, TXX9_DMA_MAX_COUNT);
735 		/*
736 		 * Workaround for ERT-TX49H2-033, ERT-TX49H3-020,
737 		 * ERT-TX49H4-016 (slightly conservative)
738 		 */
739 		if (__is_dmac64(ddev)) {
740 			if (xfer_count > 0x100 &&
741 			    (xfer_count & 0xff) >= 0xfa &&
742 			    (xfer_count & 0xff) <= 0xff)
743 				xfer_count -= 0x20;
744 		} else {
745 			if (xfer_count > 0x80 &&
746 			    (xfer_count & 0x7f) >= 0x7e &&
747 			    (xfer_count & 0x7f) <= 0x7f)
748 				xfer_count -= 0x20;
749 		}
750 
751 		desc = txx9dmac_desc_get(dc);
752 		if (!desc) {
753 			txx9dmac_desc_put(dc, first);
754 			return NULL;
755 		}
756 
757 		if (__is_dmac64(ddev)) {
758 			desc->hwdesc.SAR = src + offset;
759 			desc->hwdesc.DAR = dest + offset;
760 			desc->hwdesc.CNTR = xfer_count;
761 			txx9dmac_desc_set_nosimple(ddev, desc, 8, 8,
762 					dc->ccr | TXX9_DMA_CCR_XFACT);
763 		} else {
764 			desc->hwdesc32.SAR = src + offset;
765 			desc->hwdesc32.DAR = dest + offset;
766 			desc->hwdesc32.CNTR = xfer_count;
767 			txx9dmac_desc_set_nosimple(ddev, desc, 4, 4,
768 					dc->ccr | TXX9_DMA_CCR_XFACT);
769 		}
770 
771 		/*
772 		 * The descriptors on tx_list are not reachable from
773 		 * the dc->queue list or dc->active_list after a
774 		 * submit.  If we put all descriptors on active_list,
775 		 * calling of callback on the completion will be more
776 		 * complex.
777 		 */
778 		if (!first) {
779 			first = desc;
780 		} else {
781 			desc_write_CHAR(dc, prev, desc->txd.phys);
782 			dma_sync_single_for_device(chan2parent(&dc->chan),
783 					prev->txd.phys, ddev->descsize,
784 					DMA_TO_DEVICE);
785 			list_add_tail(&desc->desc_node, &first->tx_list);
786 		}
787 		prev = desc;
788 	}
789 
790 	/* Trigger interrupt after last block */
791 	if (flags & DMA_PREP_INTERRUPT)
792 		txx9dmac_desc_set_INTENT(ddev, prev);
793 
794 	desc_write_CHAR(dc, prev, 0);
795 	dma_sync_single_for_device(chan2parent(&dc->chan),
796 			prev->txd.phys, ddev->descsize,
797 			DMA_TO_DEVICE);
798 
799 	first->txd.flags = flags;
800 	first->len = len;
801 
802 	return &first->txd;
803 }
804 
805 static struct dma_async_tx_descriptor *
806 txx9dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
807 		unsigned int sg_len, enum dma_transfer_direction direction,
808 		unsigned long flags, void *context)
809 {
810 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
811 	struct txx9dmac_dev *ddev = dc->ddev;
812 	struct txx9dmac_slave *ds = chan->private;
813 	struct txx9dmac_desc *prev;
814 	struct txx9dmac_desc *first;
815 	unsigned int i;
816 	struct scatterlist *sg;
817 
818 	dev_vdbg(chan2dev(chan), "prep_dma_slave\n");
819 
820 	BUG_ON(!ds || !ds->reg_width);
821 	if (ds->tx_reg)
822 		BUG_ON(direction != DMA_MEM_TO_DEV);
823 	else
824 		BUG_ON(direction != DMA_DEV_TO_MEM);
825 	if (unlikely(!sg_len))
826 		return NULL;
827 
828 	prev = first = NULL;
829 
830 	for_each_sg(sgl, sg, sg_len, i) {
831 		struct txx9dmac_desc *desc;
832 		dma_addr_t mem;
833 		u32 sai, dai;
834 
835 		desc = txx9dmac_desc_get(dc);
836 		if (!desc) {
837 			txx9dmac_desc_put(dc, first);
838 			return NULL;
839 		}
840 
841 		mem = sg_dma_address(sg);
842 
843 		if (__is_dmac64(ddev)) {
844 			if (direction == DMA_MEM_TO_DEV) {
845 				desc->hwdesc.SAR = mem;
846 				desc->hwdesc.DAR = ds->tx_reg;
847 			} else {
848 				desc->hwdesc.SAR = ds->rx_reg;
849 				desc->hwdesc.DAR = mem;
850 			}
851 			desc->hwdesc.CNTR = sg_dma_len(sg);
852 		} else {
853 			if (direction == DMA_MEM_TO_DEV) {
854 				desc->hwdesc32.SAR = mem;
855 				desc->hwdesc32.DAR = ds->tx_reg;
856 			} else {
857 				desc->hwdesc32.SAR = ds->rx_reg;
858 				desc->hwdesc32.DAR = mem;
859 			}
860 			desc->hwdesc32.CNTR = sg_dma_len(sg);
861 		}
862 		if (direction == DMA_MEM_TO_DEV) {
863 			sai = ds->reg_width;
864 			dai = 0;
865 		} else {
866 			sai = 0;
867 			dai = ds->reg_width;
868 		}
869 		txx9dmac_desc_set_nosimple(ddev, desc, sai, dai,
870 					dc->ccr | TXX9_DMA_CCR_XFACT);
871 
872 		if (!first) {
873 			first = desc;
874 		} else {
875 			desc_write_CHAR(dc, prev, desc->txd.phys);
876 			dma_sync_single_for_device(chan2parent(&dc->chan),
877 					prev->txd.phys,
878 					ddev->descsize,
879 					DMA_TO_DEVICE);
880 			list_add_tail(&desc->desc_node, &first->tx_list);
881 		}
882 		prev = desc;
883 	}
884 
885 	/* Trigger interrupt after last block */
886 	if (flags & DMA_PREP_INTERRUPT)
887 		txx9dmac_desc_set_INTENT(ddev, prev);
888 
889 	desc_write_CHAR(dc, prev, 0);
890 	dma_sync_single_for_device(chan2parent(&dc->chan),
891 			prev->txd.phys, ddev->descsize,
892 			DMA_TO_DEVICE);
893 
894 	first->txd.flags = flags;
895 	first->len = 0;
896 
897 	return &first->txd;
898 }
899 
900 static int txx9dmac_terminate_all(struct dma_chan *chan)
901 {
902 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
903 	struct txx9dmac_desc *desc, *_desc;
904 	LIST_HEAD(list);
905 
906 	dev_vdbg(chan2dev(chan), "terminate_all\n");
907 	spin_lock_bh(&dc->lock);
908 
909 	txx9dmac_reset_chan(dc);
910 
911 	/* active_list entries will end up before queued entries */
912 	list_splice_init(&dc->queue, &list);
913 	list_splice_init(&dc->active_list, &list);
914 
915 	spin_unlock_bh(&dc->lock);
916 
917 	/* Flush all pending and queued descriptors */
918 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
919 		txx9dmac_descriptor_complete(dc, desc);
920 
921 	return 0;
922 }
923 
924 static enum dma_status
925 txx9dmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
926 		   struct dma_tx_state *txstate)
927 {
928 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
929 	enum dma_status ret;
930 
931 	ret = dma_cookie_status(chan, cookie, txstate);
932 	if (ret == DMA_COMPLETE)
933 		return DMA_COMPLETE;
934 
935 	spin_lock_bh(&dc->lock);
936 	txx9dmac_scan_descriptors(dc);
937 	spin_unlock_bh(&dc->lock);
938 
939 	return dma_cookie_status(chan, cookie, txstate);
940 }
941 
942 static void txx9dmac_chain_dynamic(struct txx9dmac_chan *dc,
943 				   struct txx9dmac_desc *prev)
944 {
945 	struct txx9dmac_dev *ddev = dc->ddev;
946 	struct txx9dmac_desc *desc;
947 	LIST_HEAD(list);
948 
949 	prev = txx9dmac_last_child(prev);
950 	txx9dmac_dequeue(dc, &list);
951 	desc = list_entry(list.next, struct txx9dmac_desc, desc_node);
952 	desc_write_CHAR(dc, prev, desc->txd.phys);
953 	dma_sync_single_for_device(chan2parent(&dc->chan),
954 				   prev->txd.phys, ddev->descsize,
955 				   DMA_TO_DEVICE);
956 	if (!(channel_readl(dc, CSR) & TXX9_DMA_CSR_CHNEN) &&
957 	    channel_read_CHAR(dc) == prev->txd.phys)
958 		/* Restart chain DMA */
959 		channel_write_CHAR(dc, desc->txd.phys);
960 	list_splice_tail(&list, &dc->active_list);
961 }
962 
963 static void txx9dmac_issue_pending(struct dma_chan *chan)
964 {
965 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
966 
967 	spin_lock_bh(&dc->lock);
968 
969 	if (!list_empty(&dc->active_list))
970 		txx9dmac_scan_descriptors(dc);
971 	if (!list_empty(&dc->queue)) {
972 		if (list_empty(&dc->active_list)) {
973 			txx9dmac_dequeue(dc, &dc->active_list);
974 			txx9dmac_dostart(dc, txx9dmac_first_active(dc));
975 		} else if (txx9_dma_have_SMPCHN()) {
976 			struct txx9dmac_desc *prev = txx9dmac_last_active(dc);
977 
978 			if (!(prev->txd.flags & DMA_PREP_INTERRUPT) ||
979 			    txx9dmac_chan_INTENT(dc))
980 				txx9dmac_chain_dynamic(dc, prev);
981 		}
982 	}
983 
984 	spin_unlock_bh(&dc->lock);
985 }
986 
987 static int txx9dmac_alloc_chan_resources(struct dma_chan *chan)
988 {
989 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
990 	struct txx9dmac_slave *ds = chan->private;
991 	struct txx9dmac_desc *desc;
992 	int i;
993 
994 	dev_vdbg(chan2dev(chan), "alloc_chan_resources\n");
995 
996 	/* ASSERT:  channel is idle */
997 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
998 		dev_dbg(chan2dev(chan), "DMA channel not idle?\n");
999 		return -EIO;
1000 	}
1001 
1002 	dma_cookie_init(chan);
1003 
1004 	dc->ccr = TXX9_DMA_CCR_IMMCHN | TXX9_DMA_CCR_INTENE | CCR_LE;
1005 	txx9dmac_chan_set_SMPCHN(dc);
1006 	if (!txx9_dma_have_SMPCHN() || (dc->ccr & TXX9_DMA_CCR_SMPCHN))
1007 		dc->ccr |= TXX9_DMA_CCR_INTENC;
1008 	if (chan->device->device_prep_dma_memcpy) {
1009 		if (ds)
1010 			return -EINVAL;
1011 		dc->ccr |= TXX9_DMA_CCR_XFSZ_X8;
1012 	} else {
1013 		if (!ds ||
1014 		    (ds->tx_reg && ds->rx_reg) || (!ds->tx_reg && !ds->rx_reg))
1015 			return -EINVAL;
1016 		dc->ccr |= TXX9_DMA_CCR_EXTRQ |
1017 			TXX9_DMA_CCR_XFSZ(__ffs(ds->reg_width));
1018 		txx9dmac_chan_set_INTENT(dc);
1019 	}
1020 
1021 	spin_lock_bh(&dc->lock);
1022 	i = dc->descs_allocated;
1023 	while (dc->descs_allocated < TXX9_DMA_INITIAL_DESC_COUNT) {
1024 		spin_unlock_bh(&dc->lock);
1025 
1026 		desc = txx9dmac_desc_alloc(dc, GFP_KERNEL);
1027 		if (!desc) {
1028 			dev_info(chan2dev(chan),
1029 				"only allocated %d descriptors\n", i);
1030 			spin_lock_bh(&dc->lock);
1031 			break;
1032 		}
1033 		txx9dmac_desc_put(dc, desc);
1034 
1035 		spin_lock_bh(&dc->lock);
1036 		i = ++dc->descs_allocated;
1037 	}
1038 	spin_unlock_bh(&dc->lock);
1039 
1040 	dev_dbg(chan2dev(chan),
1041 		"alloc_chan_resources allocated %d descriptors\n", i);
1042 
1043 	return i;
1044 }
1045 
1046 static void txx9dmac_free_chan_resources(struct dma_chan *chan)
1047 {
1048 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
1049 	struct txx9dmac_dev *ddev = dc->ddev;
1050 	struct txx9dmac_desc *desc, *_desc;
1051 	LIST_HEAD(list);
1052 
1053 	dev_dbg(chan2dev(chan), "free_chan_resources (descs allocated=%u)\n",
1054 			dc->descs_allocated);
1055 
1056 	/* ASSERT:  channel is idle */
1057 	BUG_ON(!list_empty(&dc->active_list));
1058 	BUG_ON(!list_empty(&dc->queue));
1059 	BUG_ON(channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT);
1060 
1061 	spin_lock_bh(&dc->lock);
1062 	list_splice_init(&dc->free_list, &list);
1063 	dc->descs_allocated = 0;
1064 	spin_unlock_bh(&dc->lock);
1065 
1066 	list_for_each_entry_safe(desc, _desc, &list, desc_node) {
1067 		dev_vdbg(chan2dev(chan), "  freeing descriptor %p\n", desc);
1068 		dma_unmap_single(chan2parent(chan), desc->txd.phys,
1069 				 ddev->descsize, DMA_TO_DEVICE);
1070 		kfree(desc);
1071 	}
1072 
1073 	dev_vdbg(chan2dev(chan), "free_chan_resources done\n");
1074 }
1075 
1076 /*----------------------------------------------------------------------*/
1077 
1078 static void txx9dmac_off(struct txx9dmac_dev *ddev)
1079 {
1080 	dma_writel(ddev, MCR, 0);
1081 }
1082 
1083 static int __init txx9dmac_chan_probe(struct platform_device *pdev)
1084 {
1085 	struct txx9dmac_chan_platform_data *cpdata =
1086 			dev_get_platdata(&pdev->dev);
1087 	struct platform_device *dmac_dev = cpdata->dmac_dev;
1088 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&dmac_dev->dev);
1089 	struct txx9dmac_chan *dc;
1090 	int err;
1091 	int ch = pdev->id % TXX9_DMA_MAX_NR_CHANNELS;
1092 	int irq;
1093 
1094 	dc = devm_kzalloc(&pdev->dev, sizeof(*dc), GFP_KERNEL);
1095 	if (!dc)
1096 		return -ENOMEM;
1097 
1098 	dc->dma.dev = &pdev->dev;
1099 	dc->dma.device_alloc_chan_resources = txx9dmac_alloc_chan_resources;
1100 	dc->dma.device_free_chan_resources = txx9dmac_free_chan_resources;
1101 	dc->dma.device_terminate_all = txx9dmac_terminate_all;
1102 	dc->dma.device_tx_status = txx9dmac_tx_status;
1103 	dc->dma.device_issue_pending = txx9dmac_issue_pending;
1104 	if (pdata && pdata->memcpy_chan == ch) {
1105 		dc->dma.device_prep_dma_memcpy = txx9dmac_prep_dma_memcpy;
1106 		dma_cap_set(DMA_MEMCPY, dc->dma.cap_mask);
1107 	} else {
1108 		dc->dma.device_prep_slave_sg = txx9dmac_prep_slave_sg;
1109 		dma_cap_set(DMA_SLAVE, dc->dma.cap_mask);
1110 		dma_cap_set(DMA_PRIVATE, dc->dma.cap_mask);
1111 	}
1112 
1113 	INIT_LIST_HEAD(&dc->dma.channels);
1114 	dc->ddev = platform_get_drvdata(dmac_dev);
1115 	if (dc->ddev->irq < 0) {
1116 		irq = platform_get_irq(pdev, 0);
1117 		if (irq < 0)
1118 			return irq;
1119 		tasklet_init(&dc->tasklet, txx9dmac_chan_tasklet,
1120 				(unsigned long)dc);
1121 		dc->irq = irq;
1122 		err = devm_request_irq(&pdev->dev, dc->irq,
1123 			txx9dmac_chan_interrupt, 0, dev_name(&pdev->dev), dc);
1124 		if (err)
1125 			return err;
1126 	} else
1127 		dc->irq = -1;
1128 	dc->ddev->chan[ch] = dc;
1129 	dc->chan.device = &dc->dma;
1130 	list_add_tail(&dc->chan.device_node, &dc->chan.device->channels);
1131 	dma_cookie_init(&dc->chan);
1132 
1133 	if (is_dmac64(dc))
1134 		dc->ch_regs = &__txx9dmac_regs(dc->ddev)->CHAN[ch];
1135 	else
1136 		dc->ch_regs = &__txx9dmac_regs32(dc->ddev)->CHAN[ch];
1137 	spin_lock_init(&dc->lock);
1138 
1139 	INIT_LIST_HEAD(&dc->active_list);
1140 	INIT_LIST_HEAD(&dc->queue);
1141 	INIT_LIST_HEAD(&dc->free_list);
1142 
1143 	txx9dmac_reset_chan(dc);
1144 
1145 	platform_set_drvdata(pdev, dc);
1146 
1147 	err = dma_async_device_register(&dc->dma);
1148 	if (err)
1149 		return err;
1150 	dev_dbg(&pdev->dev, "TXx9 DMA Channel (dma%d%s%s)\n",
1151 		dc->dma.dev_id,
1152 		dma_has_cap(DMA_MEMCPY, dc->dma.cap_mask) ? " memcpy" : "",
1153 		dma_has_cap(DMA_SLAVE, dc->dma.cap_mask) ? " slave" : "");
1154 
1155 	return 0;
1156 }
1157 
1158 static int txx9dmac_chan_remove(struct platform_device *pdev)
1159 {
1160 	struct txx9dmac_chan *dc = platform_get_drvdata(pdev);
1161 
1162 
1163 	dma_async_device_unregister(&dc->dma);
1164 	if (dc->irq >= 0) {
1165 		devm_free_irq(&pdev->dev, dc->irq, dc);
1166 		tasklet_kill(&dc->tasklet);
1167 	}
1168 	dc->ddev->chan[pdev->id % TXX9_DMA_MAX_NR_CHANNELS] = NULL;
1169 	return 0;
1170 }
1171 
1172 static int __init txx9dmac_probe(struct platform_device *pdev)
1173 {
1174 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&pdev->dev);
1175 	struct resource *io;
1176 	struct txx9dmac_dev *ddev;
1177 	u32 mcr;
1178 	int err;
1179 
1180 	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1181 	if (!io)
1182 		return -EINVAL;
1183 
1184 	ddev = devm_kzalloc(&pdev->dev, sizeof(*ddev), GFP_KERNEL);
1185 	if (!ddev)
1186 		return -ENOMEM;
1187 
1188 	if (!devm_request_mem_region(&pdev->dev, io->start, resource_size(io),
1189 				     dev_name(&pdev->dev)))
1190 		return -EBUSY;
1191 
1192 	ddev->regs = devm_ioremap(&pdev->dev, io->start, resource_size(io));
1193 	if (!ddev->regs)
1194 		return -ENOMEM;
1195 	ddev->have_64bit_regs = pdata->have_64bit_regs;
1196 	if (__is_dmac64(ddev))
1197 		ddev->descsize = sizeof(struct txx9dmac_hwdesc);
1198 	else
1199 		ddev->descsize = sizeof(struct txx9dmac_hwdesc32);
1200 
1201 	/* force dma off, just in case */
1202 	txx9dmac_off(ddev);
1203 
1204 	ddev->irq = platform_get_irq(pdev, 0);
1205 	if (ddev->irq >= 0) {
1206 		tasklet_init(&ddev->tasklet, txx9dmac_tasklet,
1207 				(unsigned long)ddev);
1208 		err = devm_request_irq(&pdev->dev, ddev->irq,
1209 			txx9dmac_interrupt, 0, dev_name(&pdev->dev), ddev);
1210 		if (err)
1211 			return err;
1212 	}
1213 
1214 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1215 	if (pdata && pdata->memcpy_chan >= 0)
1216 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1217 	dma_writel(ddev, MCR, mcr);
1218 
1219 	platform_set_drvdata(pdev, ddev);
1220 	return 0;
1221 }
1222 
1223 static int txx9dmac_remove(struct platform_device *pdev)
1224 {
1225 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1226 
1227 	txx9dmac_off(ddev);
1228 	if (ddev->irq >= 0) {
1229 		devm_free_irq(&pdev->dev, ddev->irq, ddev);
1230 		tasklet_kill(&ddev->tasklet);
1231 	}
1232 	return 0;
1233 }
1234 
1235 static void txx9dmac_shutdown(struct platform_device *pdev)
1236 {
1237 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1238 
1239 	txx9dmac_off(ddev);
1240 }
1241 
1242 static int txx9dmac_suspend_noirq(struct device *dev)
1243 {
1244 	struct txx9dmac_dev *ddev = dev_get_drvdata(dev);
1245 
1246 	txx9dmac_off(ddev);
1247 	return 0;
1248 }
1249 
1250 static int txx9dmac_resume_noirq(struct device *dev)
1251 {
1252 	struct txx9dmac_dev *ddev = dev_get_drvdata(dev);
1253 	struct txx9dmac_platform_data *pdata = dev_get_platdata(dev);
1254 	u32 mcr;
1255 
1256 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1257 	if (pdata && pdata->memcpy_chan >= 0)
1258 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1259 	dma_writel(ddev, MCR, mcr);
1260 	return 0;
1261 
1262 }
1263 
1264 static const struct dev_pm_ops txx9dmac_dev_pm_ops = {
1265 	.suspend_noirq = txx9dmac_suspend_noirq,
1266 	.resume_noirq = txx9dmac_resume_noirq,
1267 };
1268 
1269 static struct platform_driver txx9dmac_chan_driver = {
1270 	.remove		= txx9dmac_chan_remove,
1271 	.driver = {
1272 		.name	= "txx9dmac-chan",
1273 	},
1274 };
1275 
1276 static struct platform_driver txx9dmac_driver = {
1277 	.remove		= txx9dmac_remove,
1278 	.shutdown	= txx9dmac_shutdown,
1279 	.driver = {
1280 		.name	= "txx9dmac",
1281 		.pm	= &txx9dmac_dev_pm_ops,
1282 	},
1283 };
1284 
1285 static int __init txx9dmac_init(void)
1286 {
1287 	int rc;
1288 
1289 	rc = platform_driver_probe(&txx9dmac_driver, txx9dmac_probe);
1290 	if (!rc) {
1291 		rc = platform_driver_probe(&txx9dmac_chan_driver,
1292 					   txx9dmac_chan_probe);
1293 		if (rc)
1294 			platform_driver_unregister(&txx9dmac_driver);
1295 	}
1296 	return rc;
1297 }
1298 module_init(txx9dmac_init);
1299 
1300 static void __exit txx9dmac_exit(void)
1301 {
1302 	platform_driver_unregister(&txx9dmac_chan_driver);
1303 	platform_driver_unregister(&txx9dmac_driver);
1304 }
1305 module_exit(txx9dmac_exit);
1306 
1307 MODULE_LICENSE("GPL");
1308 MODULE_DESCRIPTION("TXx9 DMA Controller driver");
1309 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
1310 MODULE_ALIAS("platform:txx9dmac");
1311 MODULE_ALIAS("platform:txx9dmac-chan");
1312