xref: /openbmc/linux/drivers/dma/txx9dmac.c (revision 588b48ca)
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_64BIT_PHYS_ADDR)
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 	mmiowb();
331 }
332 
333 /* Called with dc->lock held and bh disabled */
334 static void txx9dmac_dostart(struct txx9dmac_chan *dc,
335 			     struct txx9dmac_desc *first)
336 {
337 	struct txx9dmac_slave *ds = dc->chan.private;
338 	u32 sai, dai;
339 
340 	dev_vdbg(chan2dev(&dc->chan), "dostart %u %p\n",
341 		 first->txd.cookie, first);
342 	/* ASSERT:  channel is idle */
343 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
344 		dev_err(chan2dev(&dc->chan),
345 			"BUG: Attempted to start non-idle channel\n");
346 		txx9dmac_dump_regs(dc);
347 		/* The tasklet will hopefully advance the queue... */
348 		return;
349 	}
350 
351 	if (is_dmac64(dc)) {
352 		channel64_writel(dc, CNTR, 0);
353 		channel64_writel(dc, CSR, 0xffffffff);
354 		if (ds) {
355 			if (ds->tx_reg) {
356 				sai = ds->reg_width;
357 				dai = 0;
358 			} else {
359 				sai = 0;
360 				dai = ds->reg_width;
361 			}
362 		} else {
363 			sai = 8;
364 			dai = 8;
365 		}
366 		channel64_writel(dc, SAIR, sai);
367 		channel64_writel(dc, DAIR, dai);
368 		/* All 64-bit DMAC supports SMPCHN */
369 		channel64_writel(dc, CCR, dc->ccr);
370 		/* Writing a non zero value to CHAR will assert XFACT */
371 		channel64_write_CHAR(dc, first->txd.phys);
372 	} else {
373 		channel32_writel(dc, CNTR, 0);
374 		channel32_writel(dc, CSR, 0xffffffff);
375 		if (ds) {
376 			if (ds->tx_reg) {
377 				sai = ds->reg_width;
378 				dai = 0;
379 			} else {
380 				sai = 0;
381 				dai = ds->reg_width;
382 			}
383 		} else {
384 			sai = 4;
385 			dai = 4;
386 		}
387 		channel32_writel(dc, SAIR, sai);
388 		channel32_writel(dc, DAIR, dai);
389 		if (txx9_dma_have_SMPCHN()) {
390 			channel32_writel(dc, CCR, dc->ccr);
391 			/* Writing a non zero value to CHAR will assert XFACT */
392 			channel32_writel(dc, CHAR, first->txd.phys);
393 		} else {
394 			channel32_writel(dc, CHAR, first->txd.phys);
395 			channel32_writel(dc, CCR, dc->ccr);
396 		}
397 	}
398 }
399 
400 /*----------------------------------------------------------------------*/
401 
402 static void
403 txx9dmac_descriptor_complete(struct txx9dmac_chan *dc,
404 			     struct txx9dmac_desc *desc)
405 {
406 	dma_async_tx_callback callback;
407 	void *param;
408 	struct dma_async_tx_descriptor *txd = &desc->txd;
409 
410 	dev_vdbg(chan2dev(&dc->chan), "descriptor %u %p complete\n",
411 		 txd->cookie, desc);
412 
413 	dma_cookie_complete(txd);
414 	callback = txd->callback;
415 	param = txd->callback_param;
416 
417 	txx9dmac_sync_desc_for_cpu(dc, desc);
418 	list_splice_init(&desc->tx_list, &dc->free_list);
419 	list_move(&desc->desc_node, &dc->free_list);
420 
421 	dma_descriptor_unmap(txd);
422 	/*
423 	 * The API requires that no submissions are done from a
424 	 * callback, so we don't need to drop the lock here
425 	 */
426 	if (callback)
427 		callback(param);
428 	dma_run_dependencies(txd);
429 }
430 
431 static void txx9dmac_dequeue(struct txx9dmac_chan *dc, struct list_head *list)
432 {
433 	struct txx9dmac_dev *ddev = dc->ddev;
434 	struct txx9dmac_desc *desc;
435 	struct txx9dmac_desc *prev = NULL;
436 
437 	BUG_ON(!list_empty(list));
438 	do {
439 		desc = txx9dmac_first_queued(dc);
440 		if (prev) {
441 			desc_write_CHAR(dc, prev, desc->txd.phys);
442 			dma_sync_single_for_device(chan2parent(&dc->chan),
443 				prev->txd.phys, ddev->descsize,
444 				DMA_TO_DEVICE);
445 		}
446 		prev = txx9dmac_last_child(desc);
447 		list_move_tail(&desc->desc_node, list);
448 		/* Make chain-completion interrupt happen */
449 		if ((desc->txd.flags & DMA_PREP_INTERRUPT) &&
450 		    !txx9dmac_chan_INTENT(dc))
451 			break;
452 	} while (!list_empty(&dc->queue));
453 }
454 
455 static void txx9dmac_complete_all(struct txx9dmac_chan *dc)
456 {
457 	struct txx9dmac_desc *desc, *_desc;
458 	LIST_HEAD(list);
459 
460 	/*
461 	 * Submit queued descriptors ASAP, i.e. before we go through
462 	 * the completed ones.
463 	 */
464 	list_splice_init(&dc->active_list, &list);
465 	if (!list_empty(&dc->queue)) {
466 		txx9dmac_dequeue(dc, &dc->active_list);
467 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
468 	}
469 
470 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
471 		txx9dmac_descriptor_complete(dc, desc);
472 }
473 
474 static void txx9dmac_dump_desc(struct txx9dmac_chan *dc,
475 			       struct txx9dmac_hwdesc *desc)
476 {
477 	if (is_dmac64(dc)) {
478 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
479 		dev_crit(chan2dev(&dc->chan),
480 			 "  desc: ch%#llx s%#llx d%#llx c%#x\n",
481 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR);
482 #else
483 		dev_crit(chan2dev(&dc->chan),
484 			 "  desc: ch%#llx s%#llx d%#llx c%#x"
485 			 " si%#x di%#x cc%#x cs%#x\n",
486 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR,
487 			 desc->SAIR, desc->DAIR, desc->CCR, desc->CSR);
488 #endif
489 	} else {
490 		struct txx9dmac_hwdesc32 *d = (struct txx9dmac_hwdesc32 *)desc;
491 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
492 		dev_crit(chan2dev(&dc->chan),
493 			 "  desc: ch%#x s%#x d%#x c%#x\n",
494 			 d->CHAR, d->SAR, d->DAR, d->CNTR);
495 #else
496 		dev_crit(chan2dev(&dc->chan),
497 			 "  desc: ch%#x s%#x d%#x c%#x"
498 			 " si%#x di%#x cc%#x cs%#x\n",
499 			 d->CHAR, d->SAR, d->DAR, d->CNTR,
500 			 d->SAIR, d->DAIR, d->CCR, d->CSR);
501 #endif
502 	}
503 }
504 
505 static void txx9dmac_handle_error(struct txx9dmac_chan *dc, u32 csr)
506 {
507 	struct txx9dmac_desc *bad_desc;
508 	struct txx9dmac_desc *child;
509 	u32 errors;
510 
511 	/*
512 	 * The descriptor currently at the head of the active list is
513 	 * borked. Since we don't have any way to report errors, we'll
514 	 * just have to scream loudly and try to carry on.
515 	 */
516 	dev_crit(chan2dev(&dc->chan), "Abnormal Chain Completion\n");
517 	txx9dmac_dump_regs(dc);
518 
519 	bad_desc = txx9dmac_first_active(dc);
520 	list_del_init(&bad_desc->desc_node);
521 
522 	/* Clear all error flags and try to restart the controller */
523 	errors = csr & (TXX9_DMA_CSR_ABCHC |
524 			TXX9_DMA_CSR_CFERR | TXX9_DMA_CSR_CHERR |
525 			TXX9_DMA_CSR_DESERR | TXX9_DMA_CSR_SORERR);
526 	channel_writel(dc, CSR, errors);
527 
528 	if (list_empty(&dc->active_list) && !list_empty(&dc->queue))
529 		txx9dmac_dequeue(dc, &dc->active_list);
530 	if (!list_empty(&dc->active_list))
531 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
532 
533 	dev_crit(chan2dev(&dc->chan),
534 		 "Bad descriptor submitted for DMA! (cookie: %d)\n",
535 		 bad_desc->txd.cookie);
536 	txx9dmac_dump_desc(dc, &bad_desc->hwdesc);
537 	list_for_each_entry(child, &bad_desc->tx_list, desc_node)
538 		txx9dmac_dump_desc(dc, &child->hwdesc);
539 	/* Pretend the descriptor completed successfully */
540 	txx9dmac_descriptor_complete(dc, bad_desc);
541 }
542 
543 static void txx9dmac_scan_descriptors(struct txx9dmac_chan *dc)
544 {
545 	dma_addr_t chain;
546 	struct txx9dmac_desc *desc, *_desc;
547 	struct txx9dmac_desc *child;
548 	u32 csr;
549 
550 	if (is_dmac64(dc)) {
551 		chain = channel64_read_CHAR(dc);
552 		csr = channel64_readl(dc, CSR);
553 		channel64_writel(dc, CSR, csr);
554 	} else {
555 		chain = channel32_readl(dc, CHAR);
556 		csr = channel32_readl(dc, CSR);
557 		channel32_writel(dc, CSR, csr);
558 	}
559 	/* For dynamic chain, we should look at XFACT instead of NCHNC */
560 	if (!(csr & (TXX9_DMA_CSR_XFACT | TXX9_DMA_CSR_ABCHC))) {
561 		/* Everything we've submitted is done */
562 		txx9dmac_complete_all(dc);
563 		return;
564 	}
565 	if (!(csr & TXX9_DMA_CSR_CHNEN))
566 		chain = 0;	/* last descriptor of this chain */
567 
568 	dev_vdbg(chan2dev(&dc->chan), "scan_descriptors: char=%#llx\n",
569 		 (u64)chain);
570 
571 	list_for_each_entry_safe(desc, _desc, &dc->active_list, desc_node) {
572 		if (desc_read_CHAR(dc, desc) == chain) {
573 			/* This one is currently in progress */
574 			if (csr & TXX9_DMA_CSR_ABCHC)
575 				goto scan_done;
576 			return;
577 		}
578 
579 		list_for_each_entry(child, &desc->tx_list, desc_node)
580 			if (desc_read_CHAR(dc, child) == chain) {
581 				/* Currently in progress */
582 				if (csr & TXX9_DMA_CSR_ABCHC)
583 					goto scan_done;
584 				return;
585 			}
586 
587 		/*
588 		 * No descriptors so far seem to be in progress, i.e.
589 		 * this one must be done.
590 		 */
591 		txx9dmac_descriptor_complete(dc, desc);
592 	}
593 scan_done:
594 	if (csr & TXX9_DMA_CSR_ABCHC) {
595 		txx9dmac_handle_error(dc, csr);
596 		return;
597 	}
598 
599 	dev_err(chan2dev(&dc->chan),
600 		"BUG: All descriptors done, but channel not idle!\n");
601 
602 	/* Try to continue after resetting the channel... */
603 	txx9dmac_reset_chan(dc);
604 
605 	if (!list_empty(&dc->queue)) {
606 		txx9dmac_dequeue(dc, &dc->active_list);
607 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
608 	}
609 }
610 
611 static void txx9dmac_chan_tasklet(unsigned long data)
612 {
613 	int irq;
614 	u32 csr;
615 	struct txx9dmac_chan *dc;
616 
617 	dc = (struct txx9dmac_chan *)data;
618 	csr = channel_readl(dc, CSR);
619 	dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n", csr);
620 
621 	spin_lock(&dc->lock);
622 	if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
623 		   TXX9_DMA_CSR_NTRNFC))
624 		txx9dmac_scan_descriptors(dc);
625 	spin_unlock(&dc->lock);
626 	irq = dc->irq;
627 
628 	enable_irq(irq);
629 }
630 
631 static irqreturn_t txx9dmac_chan_interrupt(int irq, void *dev_id)
632 {
633 	struct txx9dmac_chan *dc = dev_id;
634 
635 	dev_vdbg(chan2dev(&dc->chan), "interrupt: status=%#x\n",
636 			channel_readl(dc, CSR));
637 
638 	tasklet_schedule(&dc->tasklet);
639 	/*
640 	 * Just disable the interrupts. We'll turn them back on in the
641 	 * softirq handler.
642 	 */
643 	disable_irq_nosync(irq);
644 
645 	return IRQ_HANDLED;
646 }
647 
648 static void txx9dmac_tasklet(unsigned long data)
649 {
650 	int irq;
651 	u32 csr;
652 	struct txx9dmac_chan *dc;
653 
654 	struct txx9dmac_dev *ddev = (struct txx9dmac_dev *)data;
655 	u32 mcr;
656 	int i;
657 
658 	mcr = dma_readl(ddev, MCR);
659 	dev_vdbg(ddev->chan[0]->dma.dev, "tasklet: mcr=%x\n", mcr);
660 	for (i = 0; i < TXX9_DMA_MAX_NR_CHANNELS; i++) {
661 		if ((mcr >> (24 + i)) & 0x11) {
662 			dc = ddev->chan[i];
663 			csr = channel_readl(dc, CSR);
664 			dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n",
665 				 csr);
666 			spin_lock(&dc->lock);
667 			if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
668 				   TXX9_DMA_CSR_NTRNFC))
669 				txx9dmac_scan_descriptors(dc);
670 			spin_unlock(&dc->lock);
671 		}
672 	}
673 	irq = ddev->irq;
674 
675 	enable_irq(irq);
676 }
677 
678 static irqreturn_t txx9dmac_interrupt(int irq, void *dev_id)
679 {
680 	struct txx9dmac_dev *ddev = dev_id;
681 
682 	dev_vdbg(ddev->chan[0]->dma.dev, "interrupt: status=%#x\n",
683 			dma_readl(ddev, MCR));
684 
685 	tasklet_schedule(&ddev->tasklet);
686 	/*
687 	 * Just disable the interrupts. We'll turn them back on in the
688 	 * softirq handler.
689 	 */
690 	disable_irq_nosync(irq);
691 
692 	return IRQ_HANDLED;
693 }
694 
695 /*----------------------------------------------------------------------*/
696 
697 static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx)
698 {
699 	struct txx9dmac_desc *desc = txd_to_txx9dmac_desc(tx);
700 	struct txx9dmac_chan *dc = to_txx9dmac_chan(tx->chan);
701 	dma_cookie_t cookie;
702 
703 	spin_lock_bh(&dc->lock);
704 	cookie = dma_cookie_assign(tx);
705 
706 	dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u %p\n",
707 		 desc->txd.cookie, desc);
708 
709 	list_add_tail(&desc->desc_node, &dc->queue);
710 	spin_unlock_bh(&dc->lock);
711 
712 	return cookie;
713 }
714 
715 static struct dma_async_tx_descriptor *
716 txx9dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
717 		size_t len, unsigned long flags)
718 {
719 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
720 	struct txx9dmac_dev *ddev = dc->ddev;
721 	struct txx9dmac_desc *desc;
722 	struct txx9dmac_desc *first;
723 	struct txx9dmac_desc *prev;
724 	size_t xfer_count;
725 	size_t offset;
726 
727 	dev_vdbg(chan2dev(chan), "prep_dma_memcpy d%#llx s%#llx l%#zx f%#lx\n",
728 		 (u64)dest, (u64)src, len, flags);
729 
730 	if (unlikely(!len)) {
731 		dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n");
732 		return NULL;
733 	}
734 
735 	prev = first = NULL;
736 
737 	for (offset = 0; offset < len; offset += xfer_count) {
738 		xfer_count = min_t(size_t, len - offset, TXX9_DMA_MAX_COUNT);
739 		/*
740 		 * Workaround for ERT-TX49H2-033, ERT-TX49H3-020,
741 		 * ERT-TX49H4-016 (slightly conservative)
742 		 */
743 		if (__is_dmac64(ddev)) {
744 			if (xfer_count > 0x100 &&
745 			    (xfer_count & 0xff) >= 0xfa &&
746 			    (xfer_count & 0xff) <= 0xff)
747 				xfer_count -= 0x20;
748 		} else {
749 			if (xfer_count > 0x80 &&
750 			    (xfer_count & 0x7f) >= 0x7e &&
751 			    (xfer_count & 0x7f) <= 0x7f)
752 				xfer_count -= 0x20;
753 		}
754 
755 		desc = txx9dmac_desc_get(dc);
756 		if (!desc) {
757 			txx9dmac_desc_put(dc, first);
758 			return NULL;
759 		}
760 
761 		if (__is_dmac64(ddev)) {
762 			desc->hwdesc.SAR = src + offset;
763 			desc->hwdesc.DAR = dest + offset;
764 			desc->hwdesc.CNTR = xfer_count;
765 			txx9dmac_desc_set_nosimple(ddev, desc, 8, 8,
766 					dc->ccr | TXX9_DMA_CCR_XFACT);
767 		} else {
768 			desc->hwdesc32.SAR = src + offset;
769 			desc->hwdesc32.DAR = dest + offset;
770 			desc->hwdesc32.CNTR = xfer_count;
771 			txx9dmac_desc_set_nosimple(ddev, desc, 4, 4,
772 					dc->ccr | TXX9_DMA_CCR_XFACT);
773 		}
774 
775 		/*
776 		 * The descriptors on tx_list are not reachable from
777 		 * the dc->queue list or dc->active_list after a
778 		 * submit.  If we put all descriptors on active_list,
779 		 * calling of callback on the completion will be more
780 		 * complex.
781 		 */
782 		if (!first) {
783 			first = desc;
784 		} else {
785 			desc_write_CHAR(dc, prev, desc->txd.phys);
786 			dma_sync_single_for_device(chan2parent(&dc->chan),
787 					prev->txd.phys, ddev->descsize,
788 					DMA_TO_DEVICE);
789 			list_add_tail(&desc->desc_node, &first->tx_list);
790 		}
791 		prev = desc;
792 	}
793 
794 	/* Trigger interrupt after last block */
795 	if (flags & DMA_PREP_INTERRUPT)
796 		txx9dmac_desc_set_INTENT(ddev, prev);
797 
798 	desc_write_CHAR(dc, prev, 0);
799 	dma_sync_single_for_device(chan2parent(&dc->chan),
800 			prev->txd.phys, ddev->descsize,
801 			DMA_TO_DEVICE);
802 
803 	first->txd.flags = flags;
804 	first->len = len;
805 
806 	return &first->txd;
807 }
808 
809 static struct dma_async_tx_descriptor *
810 txx9dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
811 		unsigned int sg_len, enum dma_transfer_direction direction,
812 		unsigned long flags, void *context)
813 {
814 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
815 	struct txx9dmac_dev *ddev = dc->ddev;
816 	struct txx9dmac_slave *ds = chan->private;
817 	struct txx9dmac_desc *prev;
818 	struct txx9dmac_desc *first;
819 	unsigned int i;
820 	struct scatterlist *sg;
821 
822 	dev_vdbg(chan2dev(chan), "prep_dma_slave\n");
823 
824 	BUG_ON(!ds || !ds->reg_width);
825 	if (ds->tx_reg)
826 		BUG_ON(direction != DMA_MEM_TO_DEV);
827 	else
828 		BUG_ON(direction != DMA_DEV_TO_MEM);
829 	if (unlikely(!sg_len))
830 		return NULL;
831 
832 	prev = first = NULL;
833 
834 	for_each_sg(sgl, sg, sg_len, i) {
835 		struct txx9dmac_desc *desc;
836 		dma_addr_t mem;
837 		u32 sai, dai;
838 
839 		desc = txx9dmac_desc_get(dc);
840 		if (!desc) {
841 			txx9dmac_desc_put(dc, first);
842 			return NULL;
843 		}
844 
845 		mem = sg_dma_address(sg);
846 
847 		if (__is_dmac64(ddev)) {
848 			if (direction == DMA_MEM_TO_DEV) {
849 				desc->hwdesc.SAR = mem;
850 				desc->hwdesc.DAR = ds->tx_reg;
851 			} else {
852 				desc->hwdesc.SAR = ds->rx_reg;
853 				desc->hwdesc.DAR = mem;
854 			}
855 			desc->hwdesc.CNTR = sg_dma_len(sg);
856 		} else {
857 			if (direction == DMA_MEM_TO_DEV) {
858 				desc->hwdesc32.SAR = mem;
859 				desc->hwdesc32.DAR = ds->tx_reg;
860 			} else {
861 				desc->hwdesc32.SAR = ds->rx_reg;
862 				desc->hwdesc32.DAR = mem;
863 			}
864 			desc->hwdesc32.CNTR = sg_dma_len(sg);
865 		}
866 		if (direction == DMA_MEM_TO_DEV) {
867 			sai = ds->reg_width;
868 			dai = 0;
869 		} else {
870 			sai = 0;
871 			dai = ds->reg_width;
872 		}
873 		txx9dmac_desc_set_nosimple(ddev, desc, sai, dai,
874 					dc->ccr | TXX9_DMA_CCR_XFACT);
875 
876 		if (!first) {
877 			first = desc;
878 		} else {
879 			desc_write_CHAR(dc, prev, desc->txd.phys);
880 			dma_sync_single_for_device(chan2parent(&dc->chan),
881 					prev->txd.phys,
882 					ddev->descsize,
883 					DMA_TO_DEVICE);
884 			list_add_tail(&desc->desc_node, &first->tx_list);
885 		}
886 		prev = desc;
887 	}
888 
889 	/* Trigger interrupt after last block */
890 	if (flags & DMA_PREP_INTERRUPT)
891 		txx9dmac_desc_set_INTENT(ddev, prev);
892 
893 	desc_write_CHAR(dc, prev, 0);
894 	dma_sync_single_for_device(chan2parent(&dc->chan),
895 			prev->txd.phys, ddev->descsize,
896 			DMA_TO_DEVICE);
897 
898 	first->txd.flags = flags;
899 	first->len = 0;
900 
901 	return &first->txd;
902 }
903 
904 static int txx9dmac_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
905 			    unsigned long arg)
906 {
907 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
908 	struct txx9dmac_desc *desc, *_desc;
909 	LIST_HEAD(list);
910 
911 	/* Only supports DMA_TERMINATE_ALL */
912 	if (cmd != DMA_TERMINATE_ALL)
913 		return -EINVAL;
914 
915 	dev_vdbg(chan2dev(chan), "terminate_all\n");
916 	spin_lock_bh(&dc->lock);
917 
918 	txx9dmac_reset_chan(dc);
919 
920 	/* active_list entries will end up before queued entries */
921 	list_splice_init(&dc->queue, &list);
922 	list_splice_init(&dc->active_list, &list);
923 
924 	spin_unlock_bh(&dc->lock);
925 
926 	/* Flush all pending and queued descriptors */
927 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
928 		txx9dmac_descriptor_complete(dc, desc);
929 
930 	return 0;
931 }
932 
933 static enum dma_status
934 txx9dmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
935 		   struct dma_tx_state *txstate)
936 {
937 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
938 	enum dma_status ret;
939 
940 	ret = dma_cookie_status(chan, cookie, txstate);
941 	if (ret == DMA_COMPLETE)
942 		return DMA_COMPLETE;
943 
944 	spin_lock_bh(&dc->lock);
945 	txx9dmac_scan_descriptors(dc);
946 	spin_unlock_bh(&dc->lock);
947 
948 	return dma_cookie_status(chan, cookie, txstate);
949 }
950 
951 static void txx9dmac_chain_dynamic(struct txx9dmac_chan *dc,
952 				   struct txx9dmac_desc *prev)
953 {
954 	struct txx9dmac_dev *ddev = dc->ddev;
955 	struct txx9dmac_desc *desc;
956 	LIST_HEAD(list);
957 
958 	prev = txx9dmac_last_child(prev);
959 	txx9dmac_dequeue(dc, &list);
960 	desc = list_entry(list.next, struct txx9dmac_desc, desc_node);
961 	desc_write_CHAR(dc, prev, desc->txd.phys);
962 	dma_sync_single_for_device(chan2parent(&dc->chan),
963 				   prev->txd.phys, ddev->descsize,
964 				   DMA_TO_DEVICE);
965 	mmiowb();
966 	if (!(channel_readl(dc, CSR) & TXX9_DMA_CSR_CHNEN) &&
967 	    channel_read_CHAR(dc) == prev->txd.phys)
968 		/* Restart chain DMA */
969 		channel_write_CHAR(dc, desc->txd.phys);
970 	list_splice_tail(&list, &dc->active_list);
971 }
972 
973 static void txx9dmac_issue_pending(struct dma_chan *chan)
974 {
975 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
976 
977 	spin_lock_bh(&dc->lock);
978 
979 	if (!list_empty(&dc->active_list))
980 		txx9dmac_scan_descriptors(dc);
981 	if (!list_empty(&dc->queue)) {
982 		if (list_empty(&dc->active_list)) {
983 			txx9dmac_dequeue(dc, &dc->active_list);
984 			txx9dmac_dostart(dc, txx9dmac_first_active(dc));
985 		} else if (txx9_dma_have_SMPCHN()) {
986 			struct txx9dmac_desc *prev = txx9dmac_last_active(dc);
987 
988 			if (!(prev->txd.flags & DMA_PREP_INTERRUPT) ||
989 			    txx9dmac_chan_INTENT(dc))
990 				txx9dmac_chain_dynamic(dc, prev);
991 		}
992 	}
993 
994 	spin_unlock_bh(&dc->lock);
995 }
996 
997 static int txx9dmac_alloc_chan_resources(struct dma_chan *chan)
998 {
999 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
1000 	struct txx9dmac_slave *ds = chan->private;
1001 	struct txx9dmac_desc *desc;
1002 	int i;
1003 
1004 	dev_vdbg(chan2dev(chan), "alloc_chan_resources\n");
1005 
1006 	/* ASSERT:  channel is idle */
1007 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
1008 		dev_dbg(chan2dev(chan), "DMA channel not idle?\n");
1009 		return -EIO;
1010 	}
1011 
1012 	dma_cookie_init(chan);
1013 
1014 	dc->ccr = TXX9_DMA_CCR_IMMCHN | TXX9_DMA_CCR_INTENE | CCR_LE;
1015 	txx9dmac_chan_set_SMPCHN(dc);
1016 	if (!txx9_dma_have_SMPCHN() || (dc->ccr & TXX9_DMA_CCR_SMPCHN))
1017 		dc->ccr |= TXX9_DMA_CCR_INTENC;
1018 	if (chan->device->device_prep_dma_memcpy) {
1019 		if (ds)
1020 			return -EINVAL;
1021 		dc->ccr |= TXX9_DMA_CCR_XFSZ_X8;
1022 	} else {
1023 		if (!ds ||
1024 		    (ds->tx_reg && ds->rx_reg) || (!ds->tx_reg && !ds->rx_reg))
1025 			return -EINVAL;
1026 		dc->ccr |= TXX9_DMA_CCR_EXTRQ |
1027 			TXX9_DMA_CCR_XFSZ(__ffs(ds->reg_width));
1028 		txx9dmac_chan_set_INTENT(dc);
1029 	}
1030 
1031 	spin_lock_bh(&dc->lock);
1032 	i = dc->descs_allocated;
1033 	while (dc->descs_allocated < TXX9_DMA_INITIAL_DESC_COUNT) {
1034 		spin_unlock_bh(&dc->lock);
1035 
1036 		desc = txx9dmac_desc_alloc(dc, GFP_KERNEL);
1037 		if (!desc) {
1038 			dev_info(chan2dev(chan),
1039 				"only allocated %d descriptors\n", i);
1040 			spin_lock_bh(&dc->lock);
1041 			break;
1042 		}
1043 		txx9dmac_desc_put(dc, desc);
1044 
1045 		spin_lock_bh(&dc->lock);
1046 		i = ++dc->descs_allocated;
1047 	}
1048 	spin_unlock_bh(&dc->lock);
1049 
1050 	dev_dbg(chan2dev(chan),
1051 		"alloc_chan_resources allocated %d descriptors\n", i);
1052 
1053 	return i;
1054 }
1055 
1056 static void txx9dmac_free_chan_resources(struct dma_chan *chan)
1057 {
1058 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
1059 	struct txx9dmac_dev *ddev = dc->ddev;
1060 	struct txx9dmac_desc *desc, *_desc;
1061 	LIST_HEAD(list);
1062 
1063 	dev_dbg(chan2dev(chan), "free_chan_resources (descs allocated=%u)\n",
1064 			dc->descs_allocated);
1065 
1066 	/* ASSERT:  channel is idle */
1067 	BUG_ON(!list_empty(&dc->active_list));
1068 	BUG_ON(!list_empty(&dc->queue));
1069 	BUG_ON(channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT);
1070 
1071 	spin_lock_bh(&dc->lock);
1072 	list_splice_init(&dc->free_list, &list);
1073 	dc->descs_allocated = 0;
1074 	spin_unlock_bh(&dc->lock);
1075 
1076 	list_for_each_entry_safe(desc, _desc, &list, desc_node) {
1077 		dev_vdbg(chan2dev(chan), "  freeing descriptor %p\n", desc);
1078 		dma_unmap_single(chan2parent(chan), desc->txd.phys,
1079 				 ddev->descsize, DMA_TO_DEVICE);
1080 		kfree(desc);
1081 	}
1082 
1083 	dev_vdbg(chan2dev(chan), "free_chan_resources done\n");
1084 }
1085 
1086 /*----------------------------------------------------------------------*/
1087 
1088 static void txx9dmac_off(struct txx9dmac_dev *ddev)
1089 {
1090 	dma_writel(ddev, MCR, 0);
1091 	mmiowb();
1092 }
1093 
1094 static int __init txx9dmac_chan_probe(struct platform_device *pdev)
1095 {
1096 	struct txx9dmac_chan_platform_data *cpdata =
1097 			dev_get_platdata(&pdev->dev);
1098 	struct platform_device *dmac_dev = cpdata->dmac_dev;
1099 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&dmac_dev->dev);
1100 	struct txx9dmac_chan *dc;
1101 	int err;
1102 	int ch = pdev->id % TXX9_DMA_MAX_NR_CHANNELS;
1103 	int irq;
1104 
1105 	dc = devm_kzalloc(&pdev->dev, sizeof(*dc), GFP_KERNEL);
1106 	if (!dc)
1107 		return -ENOMEM;
1108 
1109 	dc->dma.dev = &pdev->dev;
1110 	dc->dma.device_alloc_chan_resources = txx9dmac_alloc_chan_resources;
1111 	dc->dma.device_free_chan_resources = txx9dmac_free_chan_resources;
1112 	dc->dma.device_control = txx9dmac_control;
1113 	dc->dma.device_tx_status = txx9dmac_tx_status;
1114 	dc->dma.device_issue_pending = txx9dmac_issue_pending;
1115 	if (pdata && pdata->memcpy_chan == ch) {
1116 		dc->dma.device_prep_dma_memcpy = txx9dmac_prep_dma_memcpy;
1117 		dma_cap_set(DMA_MEMCPY, dc->dma.cap_mask);
1118 	} else {
1119 		dc->dma.device_prep_slave_sg = txx9dmac_prep_slave_sg;
1120 		dma_cap_set(DMA_SLAVE, dc->dma.cap_mask);
1121 		dma_cap_set(DMA_PRIVATE, dc->dma.cap_mask);
1122 	}
1123 
1124 	INIT_LIST_HEAD(&dc->dma.channels);
1125 	dc->ddev = platform_get_drvdata(dmac_dev);
1126 	if (dc->ddev->irq < 0) {
1127 		irq = platform_get_irq(pdev, 0);
1128 		if (irq < 0)
1129 			return irq;
1130 		tasklet_init(&dc->tasklet, txx9dmac_chan_tasklet,
1131 				(unsigned long)dc);
1132 		dc->irq = irq;
1133 		err = devm_request_irq(&pdev->dev, dc->irq,
1134 			txx9dmac_chan_interrupt, 0, dev_name(&pdev->dev), dc);
1135 		if (err)
1136 			return err;
1137 	} else
1138 		dc->irq = -1;
1139 	dc->ddev->chan[ch] = dc;
1140 	dc->chan.device = &dc->dma;
1141 	list_add_tail(&dc->chan.device_node, &dc->chan.device->channels);
1142 	dma_cookie_init(&dc->chan);
1143 
1144 	if (is_dmac64(dc))
1145 		dc->ch_regs = &__txx9dmac_regs(dc->ddev)->CHAN[ch];
1146 	else
1147 		dc->ch_regs = &__txx9dmac_regs32(dc->ddev)->CHAN[ch];
1148 	spin_lock_init(&dc->lock);
1149 
1150 	INIT_LIST_HEAD(&dc->active_list);
1151 	INIT_LIST_HEAD(&dc->queue);
1152 	INIT_LIST_HEAD(&dc->free_list);
1153 
1154 	txx9dmac_reset_chan(dc);
1155 
1156 	platform_set_drvdata(pdev, dc);
1157 
1158 	err = dma_async_device_register(&dc->dma);
1159 	if (err)
1160 		return err;
1161 	dev_dbg(&pdev->dev, "TXx9 DMA Channel (dma%d%s%s)\n",
1162 		dc->dma.dev_id,
1163 		dma_has_cap(DMA_MEMCPY, dc->dma.cap_mask) ? " memcpy" : "",
1164 		dma_has_cap(DMA_SLAVE, dc->dma.cap_mask) ? " slave" : "");
1165 
1166 	return 0;
1167 }
1168 
1169 static int txx9dmac_chan_remove(struct platform_device *pdev)
1170 {
1171 	struct txx9dmac_chan *dc = platform_get_drvdata(pdev);
1172 
1173 	dma_async_device_unregister(&dc->dma);
1174 	if (dc->irq >= 0)
1175 		tasklet_kill(&dc->tasklet);
1176 	dc->ddev->chan[pdev->id % TXX9_DMA_MAX_NR_CHANNELS] = NULL;
1177 	return 0;
1178 }
1179 
1180 static int __init txx9dmac_probe(struct platform_device *pdev)
1181 {
1182 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&pdev->dev);
1183 	struct resource *io;
1184 	struct txx9dmac_dev *ddev;
1185 	u32 mcr;
1186 	int err;
1187 
1188 	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1189 	if (!io)
1190 		return -EINVAL;
1191 
1192 	ddev = devm_kzalloc(&pdev->dev, sizeof(*ddev), GFP_KERNEL);
1193 	if (!ddev)
1194 		return -ENOMEM;
1195 
1196 	if (!devm_request_mem_region(&pdev->dev, io->start, resource_size(io),
1197 				     dev_name(&pdev->dev)))
1198 		return -EBUSY;
1199 
1200 	ddev->regs = devm_ioremap(&pdev->dev, io->start, resource_size(io));
1201 	if (!ddev->regs)
1202 		return -ENOMEM;
1203 	ddev->have_64bit_regs = pdata->have_64bit_regs;
1204 	if (__is_dmac64(ddev))
1205 		ddev->descsize = sizeof(struct txx9dmac_hwdesc);
1206 	else
1207 		ddev->descsize = sizeof(struct txx9dmac_hwdesc32);
1208 
1209 	/* force dma off, just in case */
1210 	txx9dmac_off(ddev);
1211 
1212 	ddev->irq = platform_get_irq(pdev, 0);
1213 	if (ddev->irq >= 0) {
1214 		tasklet_init(&ddev->tasklet, txx9dmac_tasklet,
1215 				(unsigned long)ddev);
1216 		err = devm_request_irq(&pdev->dev, ddev->irq,
1217 			txx9dmac_interrupt, 0, dev_name(&pdev->dev), ddev);
1218 		if (err)
1219 			return err;
1220 	}
1221 
1222 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1223 	if (pdata && pdata->memcpy_chan >= 0)
1224 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1225 	dma_writel(ddev, MCR, mcr);
1226 
1227 	platform_set_drvdata(pdev, ddev);
1228 	return 0;
1229 }
1230 
1231 static int txx9dmac_remove(struct platform_device *pdev)
1232 {
1233 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1234 
1235 	txx9dmac_off(ddev);
1236 	if (ddev->irq >= 0)
1237 		tasklet_kill(&ddev->tasklet);
1238 	return 0;
1239 }
1240 
1241 static void txx9dmac_shutdown(struct platform_device *pdev)
1242 {
1243 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1244 
1245 	txx9dmac_off(ddev);
1246 }
1247 
1248 static int txx9dmac_suspend_noirq(struct device *dev)
1249 {
1250 	struct platform_device *pdev = to_platform_device(dev);
1251 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1252 
1253 	txx9dmac_off(ddev);
1254 	return 0;
1255 }
1256 
1257 static int txx9dmac_resume_noirq(struct device *dev)
1258 {
1259 	struct platform_device *pdev = to_platform_device(dev);
1260 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1261 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&pdev->dev);
1262 	u32 mcr;
1263 
1264 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1265 	if (pdata && pdata->memcpy_chan >= 0)
1266 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1267 	dma_writel(ddev, MCR, mcr);
1268 	return 0;
1269 
1270 }
1271 
1272 static const struct dev_pm_ops txx9dmac_dev_pm_ops = {
1273 	.suspend_noirq = txx9dmac_suspend_noirq,
1274 	.resume_noirq = txx9dmac_resume_noirq,
1275 };
1276 
1277 static struct platform_driver txx9dmac_chan_driver = {
1278 	.remove		= txx9dmac_chan_remove,
1279 	.driver = {
1280 		.name	= "txx9dmac-chan",
1281 	},
1282 };
1283 
1284 static struct platform_driver txx9dmac_driver = {
1285 	.remove		= txx9dmac_remove,
1286 	.shutdown	= txx9dmac_shutdown,
1287 	.driver = {
1288 		.name	= "txx9dmac",
1289 		.pm	= &txx9dmac_dev_pm_ops,
1290 	},
1291 };
1292 
1293 static int __init txx9dmac_init(void)
1294 {
1295 	int rc;
1296 
1297 	rc = platform_driver_probe(&txx9dmac_driver, txx9dmac_probe);
1298 	if (!rc) {
1299 		rc = platform_driver_probe(&txx9dmac_chan_driver,
1300 					   txx9dmac_chan_probe);
1301 		if (rc)
1302 			platform_driver_unregister(&txx9dmac_driver);
1303 	}
1304 	return rc;
1305 }
1306 module_init(txx9dmac_init);
1307 
1308 static void __exit txx9dmac_exit(void)
1309 {
1310 	platform_driver_unregister(&txx9dmac_chan_driver);
1311 	platform_driver_unregister(&txx9dmac_driver);
1312 }
1313 module_exit(txx9dmac_exit);
1314 
1315 MODULE_LICENSE("GPL");
1316 MODULE_DESCRIPTION("TXx9 DMA Controller driver");
1317 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
1318 MODULE_ALIAS("platform:txx9dmac");
1319 MODULE_ALIAS("platform:txx9dmac-chan");
1320