xref: /openbmc/linux/drivers/dma/txx9dmac.c (revision ab589bac)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for the TXx9 SoC DMA Controller
4  *
5  * Copyright (C) 2009 Atsushi Nemoto
6  */
7 #include <linux/dma-mapping.h>
8 #include <linux/init.h>
9 #include <linux/interrupt.h>
10 #include <linux/io.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/slab.h>
14 #include <linux/scatterlist.h>
15 
16 #include "dmaengine.h"
17 #include "txx9dmac.h"
18 
19 static struct txx9dmac_chan *to_txx9dmac_chan(struct dma_chan *chan)
20 {
21 	return container_of(chan, struct txx9dmac_chan, chan);
22 }
23 
24 static struct txx9dmac_cregs __iomem *__dma_regs(const struct txx9dmac_chan *dc)
25 {
26 	return dc->ch_regs;
27 }
28 
29 static struct txx9dmac_cregs32 __iomem *__dma_regs32(
30 	const struct txx9dmac_chan *dc)
31 {
32 	return dc->ch_regs;
33 }
34 
35 #define channel64_readq(dc, name) \
36 	__raw_readq(&(__dma_regs(dc)->name))
37 #define channel64_writeq(dc, name, val) \
38 	__raw_writeq((val), &(__dma_regs(dc)->name))
39 #define channel64_readl(dc, name) \
40 	__raw_readl(&(__dma_regs(dc)->name))
41 #define channel64_writel(dc, name, val) \
42 	__raw_writel((val), &(__dma_regs(dc)->name))
43 
44 #define channel32_readl(dc, name) \
45 	__raw_readl(&(__dma_regs32(dc)->name))
46 #define channel32_writel(dc, name, val) \
47 	__raw_writel((val), &(__dma_regs32(dc)->name))
48 
49 #define channel_readq(dc, name) channel64_readq(dc, name)
50 #define channel_writeq(dc, name, val) channel64_writeq(dc, name, val)
51 #define channel_readl(dc, name) \
52 	(is_dmac64(dc) ? \
53 	 channel64_readl(dc, name) : channel32_readl(dc, name))
54 #define channel_writel(dc, name, val) \
55 	(is_dmac64(dc) ? \
56 	 channel64_writel(dc, name, val) : channel32_writel(dc, name, val))
57 
58 static dma_addr_t channel64_read_CHAR(const struct txx9dmac_chan *dc)
59 {
60 	if (sizeof(__dma_regs(dc)->CHAR) == sizeof(u64))
61 		return channel64_readq(dc, CHAR);
62 	else
63 		return channel64_readl(dc, CHAR);
64 }
65 
66 static void channel64_write_CHAR(const struct txx9dmac_chan *dc, dma_addr_t val)
67 {
68 	if (sizeof(__dma_regs(dc)->CHAR) == sizeof(u64))
69 		channel64_writeq(dc, CHAR, val);
70 	else
71 		channel64_writel(dc, CHAR, val);
72 }
73 
74 static void channel64_clear_CHAR(const struct txx9dmac_chan *dc)
75 {
76 #if defined(CONFIG_32BIT) && !defined(CONFIG_PHYS_ADDR_T_64BIT)
77 	channel64_writel(dc, CHAR, 0);
78 	channel64_writel(dc, __pad_CHAR, 0);
79 #else
80 	channel64_writeq(dc, CHAR, 0);
81 #endif
82 }
83 
84 static dma_addr_t channel_read_CHAR(const struct txx9dmac_chan *dc)
85 {
86 	if (is_dmac64(dc))
87 		return channel64_read_CHAR(dc);
88 	else
89 		return channel32_readl(dc, CHAR);
90 }
91 
92 static void channel_write_CHAR(const struct txx9dmac_chan *dc, dma_addr_t val)
93 {
94 	if (is_dmac64(dc))
95 		channel64_write_CHAR(dc, val);
96 	else
97 		channel32_writel(dc, CHAR, val);
98 }
99 
100 static struct txx9dmac_regs __iomem *__txx9dmac_regs(
101 	const struct txx9dmac_dev *ddev)
102 {
103 	return ddev->regs;
104 }
105 
106 static struct txx9dmac_regs32 __iomem *__txx9dmac_regs32(
107 	const struct txx9dmac_dev *ddev)
108 {
109 	return ddev->regs;
110 }
111 
112 #define dma64_readl(ddev, name) \
113 	__raw_readl(&(__txx9dmac_regs(ddev)->name))
114 #define dma64_writel(ddev, name, val) \
115 	__raw_writel((val), &(__txx9dmac_regs(ddev)->name))
116 
117 #define dma32_readl(ddev, name) \
118 	__raw_readl(&(__txx9dmac_regs32(ddev)->name))
119 #define dma32_writel(ddev, name, val) \
120 	__raw_writel((val), &(__txx9dmac_regs32(ddev)->name))
121 
122 #define dma_readl(ddev, name) \
123 	(__is_dmac64(ddev) ? \
124 	dma64_readl(ddev, name) : dma32_readl(ddev, name))
125 #define dma_writel(ddev, name, val) \
126 	(__is_dmac64(ddev) ? \
127 	dma64_writel(ddev, name, val) : dma32_writel(ddev, name, val))
128 
129 static struct device *chan2dev(struct dma_chan *chan)
130 {
131 	return &chan->dev->device;
132 }
133 static struct device *chan2parent(struct dma_chan *chan)
134 {
135 	return chan->dev->device.parent;
136 }
137 
138 static struct txx9dmac_desc *
139 txd_to_txx9dmac_desc(struct dma_async_tx_descriptor *txd)
140 {
141 	return container_of(txd, struct txx9dmac_desc, txd);
142 }
143 
144 static dma_addr_t desc_read_CHAR(const struct txx9dmac_chan *dc,
145 				 const struct txx9dmac_desc *desc)
146 {
147 	return is_dmac64(dc) ? desc->hwdesc.CHAR : desc->hwdesc32.CHAR;
148 }
149 
150 static void desc_write_CHAR(const struct txx9dmac_chan *dc,
151 			    struct txx9dmac_desc *desc, dma_addr_t val)
152 {
153 	if (is_dmac64(dc))
154 		desc->hwdesc.CHAR = val;
155 	else
156 		desc->hwdesc32.CHAR = val;
157 }
158 
159 #define TXX9_DMA_MAX_COUNT	0x04000000
160 
161 #define TXX9_DMA_INITIAL_DESC_COUNT	64
162 
163 static struct txx9dmac_desc *txx9dmac_first_active(struct txx9dmac_chan *dc)
164 {
165 	return list_entry(dc->active_list.next,
166 			  struct txx9dmac_desc, desc_node);
167 }
168 
169 static struct txx9dmac_desc *txx9dmac_last_active(struct txx9dmac_chan *dc)
170 {
171 	return list_entry(dc->active_list.prev,
172 			  struct txx9dmac_desc, desc_node);
173 }
174 
175 static struct txx9dmac_desc *txx9dmac_first_queued(struct txx9dmac_chan *dc)
176 {
177 	return list_entry(dc->queue.next, struct txx9dmac_desc, desc_node);
178 }
179 
180 static struct txx9dmac_desc *txx9dmac_last_child(struct txx9dmac_desc *desc)
181 {
182 	if (!list_empty(&desc->tx_list))
183 		desc = list_entry(desc->tx_list.prev, typeof(*desc), desc_node);
184 	return desc;
185 }
186 
187 static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx);
188 
189 static struct txx9dmac_desc *txx9dmac_desc_alloc(struct txx9dmac_chan *dc,
190 						 gfp_t flags)
191 {
192 	struct txx9dmac_dev *ddev = dc->ddev;
193 	struct txx9dmac_desc *desc;
194 
195 	desc = kzalloc(sizeof(*desc), flags);
196 	if (!desc)
197 		return NULL;
198 	INIT_LIST_HEAD(&desc->tx_list);
199 	dma_async_tx_descriptor_init(&desc->txd, &dc->chan);
200 	desc->txd.tx_submit = txx9dmac_tx_submit;
201 	/* txd.flags will be overwritten in prep funcs */
202 	desc->txd.flags = DMA_CTRL_ACK;
203 	desc->txd.phys = dma_map_single(chan2parent(&dc->chan), &desc->hwdesc,
204 					ddev->descsize, DMA_TO_DEVICE);
205 	return desc;
206 }
207 
208 static struct txx9dmac_desc *txx9dmac_desc_get(struct txx9dmac_chan *dc)
209 {
210 	struct txx9dmac_desc *desc, *_desc;
211 	struct txx9dmac_desc *ret = NULL;
212 	unsigned int i = 0;
213 
214 	spin_lock_bh(&dc->lock);
215 	list_for_each_entry_safe(desc, _desc, &dc->free_list, desc_node) {
216 		if (async_tx_test_ack(&desc->txd)) {
217 			list_del(&desc->desc_node);
218 			ret = desc;
219 			break;
220 		}
221 		dev_dbg(chan2dev(&dc->chan), "desc %p not ACKed\n", desc);
222 		i++;
223 	}
224 	spin_unlock_bh(&dc->lock);
225 
226 	dev_vdbg(chan2dev(&dc->chan), "scanned %u descriptors on freelist\n",
227 		 i);
228 	if (!ret) {
229 		ret = txx9dmac_desc_alloc(dc, GFP_ATOMIC);
230 		if (ret) {
231 			spin_lock_bh(&dc->lock);
232 			dc->descs_allocated++;
233 			spin_unlock_bh(&dc->lock);
234 		} else
235 			dev_err(chan2dev(&dc->chan),
236 				"not enough descriptors available\n");
237 	}
238 	return ret;
239 }
240 
241 static void txx9dmac_sync_desc_for_cpu(struct txx9dmac_chan *dc,
242 				       struct txx9dmac_desc *desc)
243 {
244 	struct txx9dmac_dev *ddev = dc->ddev;
245 	struct txx9dmac_desc *child;
246 
247 	list_for_each_entry(child, &desc->tx_list, desc_node)
248 		dma_sync_single_for_cpu(chan2parent(&dc->chan),
249 				child->txd.phys, ddev->descsize,
250 				DMA_TO_DEVICE);
251 	dma_sync_single_for_cpu(chan2parent(&dc->chan),
252 			desc->txd.phys, ddev->descsize,
253 			DMA_TO_DEVICE);
254 }
255 
256 /*
257  * Move a descriptor, including any children, to the free list.
258  * `desc' must not be on any lists.
259  */
260 static void txx9dmac_desc_put(struct txx9dmac_chan *dc,
261 			      struct txx9dmac_desc *desc)
262 {
263 	if (desc) {
264 		struct txx9dmac_desc *child;
265 
266 		txx9dmac_sync_desc_for_cpu(dc, desc);
267 
268 		spin_lock_bh(&dc->lock);
269 		list_for_each_entry(child, &desc->tx_list, desc_node)
270 			dev_vdbg(chan2dev(&dc->chan),
271 				 "moving child desc %p to freelist\n",
272 				 child);
273 		list_splice_init(&desc->tx_list, &dc->free_list);
274 		dev_vdbg(chan2dev(&dc->chan), "moving desc %p to freelist\n",
275 			 desc);
276 		list_add(&desc->desc_node, &dc->free_list);
277 		spin_unlock_bh(&dc->lock);
278 	}
279 }
280 
281 /*----------------------------------------------------------------------*/
282 
283 static void txx9dmac_dump_regs(struct txx9dmac_chan *dc)
284 {
285 	if (is_dmac64(dc))
286 		dev_err(chan2dev(&dc->chan),
287 			"  CHAR: %#llx SAR: %#llx DAR: %#llx CNTR: %#x"
288 			" SAIR: %#x DAIR: %#x CCR: %#x CSR: %#x\n",
289 			(u64)channel64_read_CHAR(dc),
290 			channel64_readq(dc, SAR),
291 			channel64_readq(dc, DAR),
292 			channel64_readl(dc, CNTR),
293 			channel64_readl(dc, SAIR),
294 			channel64_readl(dc, DAIR),
295 			channel64_readl(dc, CCR),
296 			channel64_readl(dc, CSR));
297 	else
298 		dev_err(chan2dev(&dc->chan),
299 			"  CHAR: %#x SAR: %#x DAR: %#x CNTR: %#x"
300 			" SAIR: %#x DAIR: %#x CCR: %#x CSR: %#x\n",
301 			channel32_readl(dc, CHAR),
302 			channel32_readl(dc, SAR),
303 			channel32_readl(dc, DAR),
304 			channel32_readl(dc, CNTR),
305 			channel32_readl(dc, SAIR),
306 			channel32_readl(dc, DAIR),
307 			channel32_readl(dc, CCR),
308 			channel32_readl(dc, CSR));
309 }
310 
311 static void txx9dmac_reset_chan(struct txx9dmac_chan *dc)
312 {
313 	channel_writel(dc, CCR, TXX9_DMA_CCR_CHRST);
314 	if (is_dmac64(dc)) {
315 		channel64_clear_CHAR(dc);
316 		channel_writeq(dc, SAR, 0);
317 		channel_writeq(dc, DAR, 0);
318 	} else {
319 		channel_writel(dc, CHAR, 0);
320 		channel_writel(dc, SAR, 0);
321 		channel_writel(dc, DAR, 0);
322 	}
323 	channel_writel(dc, CNTR, 0);
324 	channel_writel(dc, SAIR, 0);
325 	channel_writel(dc, DAIR, 0);
326 	channel_writel(dc, CCR, 0);
327 }
328 
329 /* Called with dc->lock held and bh disabled */
330 static void txx9dmac_dostart(struct txx9dmac_chan *dc,
331 			     struct txx9dmac_desc *first)
332 {
333 	struct txx9dmac_slave *ds = dc->chan.private;
334 	u32 sai, dai;
335 
336 	dev_vdbg(chan2dev(&dc->chan), "dostart %u %p\n",
337 		 first->txd.cookie, first);
338 	/* ASSERT:  channel is idle */
339 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
340 		dev_err(chan2dev(&dc->chan),
341 			"BUG: Attempted to start non-idle channel\n");
342 		txx9dmac_dump_regs(dc);
343 		/* The tasklet will hopefully advance the queue... */
344 		return;
345 	}
346 
347 	if (is_dmac64(dc)) {
348 		channel64_writel(dc, CNTR, 0);
349 		channel64_writel(dc, CSR, 0xffffffff);
350 		if (ds) {
351 			if (ds->tx_reg) {
352 				sai = ds->reg_width;
353 				dai = 0;
354 			} else {
355 				sai = 0;
356 				dai = ds->reg_width;
357 			}
358 		} else {
359 			sai = 8;
360 			dai = 8;
361 		}
362 		channel64_writel(dc, SAIR, sai);
363 		channel64_writel(dc, DAIR, dai);
364 		/* All 64-bit DMAC supports SMPCHN */
365 		channel64_writel(dc, CCR, dc->ccr);
366 		/* Writing a non zero value to CHAR will assert XFACT */
367 		channel64_write_CHAR(dc, first->txd.phys);
368 	} else {
369 		channel32_writel(dc, CNTR, 0);
370 		channel32_writel(dc, CSR, 0xffffffff);
371 		if (ds) {
372 			if (ds->tx_reg) {
373 				sai = ds->reg_width;
374 				dai = 0;
375 			} else {
376 				sai = 0;
377 				dai = ds->reg_width;
378 			}
379 		} else {
380 			sai = 4;
381 			dai = 4;
382 		}
383 		channel32_writel(dc, SAIR, sai);
384 		channel32_writel(dc, DAIR, dai);
385 		if (txx9_dma_have_SMPCHN()) {
386 			channel32_writel(dc, CCR, dc->ccr);
387 			/* Writing a non zero value to CHAR will assert XFACT */
388 			channel32_writel(dc, CHAR, first->txd.phys);
389 		} else {
390 			channel32_writel(dc, CHAR, first->txd.phys);
391 			channel32_writel(dc, CCR, dc->ccr);
392 		}
393 	}
394 }
395 
396 /*----------------------------------------------------------------------*/
397 
398 static void
399 txx9dmac_descriptor_complete(struct txx9dmac_chan *dc,
400 			     struct txx9dmac_desc *desc)
401 {
402 	struct dmaengine_desc_callback cb;
403 	struct dma_async_tx_descriptor *txd = &desc->txd;
404 
405 	dev_vdbg(chan2dev(&dc->chan), "descriptor %u %p complete\n",
406 		 txd->cookie, desc);
407 
408 	dma_cookie_complete(txd);
409 	dmaengine_desc_get_callback(txd, &cb);
410 
411 	txx9dmac_sync_desc_for_cpu(dc, desc);
412 	list_splice_init(&desc->tx_list, &dc->free_list);
413 	list_move(&desc->desc_node, &dc->free_list);
414 
415 	dma_descriptor_unmap(txd);
416 	/*
417 	 * The API requires that no submissions are done from a
418 	 * callback, so we don't need to drop the lock here
419 	 */
420 	dmaengine_desc_callback_invoke(&cb, NULL);
421 	dma_run_dependencies(txd);
422 }
423 
424 static void txx9dmac_dequeue(struct txx9dmac_chan *dc, struct list_head *list)
425 {
426 	struct txx9dmac_dev *ddev = dc->ddev;
427 	struct txx9dmac_desc *desc;
428 	struct txx9dmac_desc *prev = NULL;
429 
430 	BUG_ON(!list_empty(list));
431 	do {
432 		desc = txx9dmac_first_queued(dc);
433 		if (prev) {
434 			desc_write_CHAR(dc, prev, desc->txd.phys);
435 			dma_sync_single_for_device(chan2parent(&dc->chan),
436 				prev->txd.phys, ddev->descsize,
437 				DMA_TO_DEVICE);
438 		}
439 		prev = txx9dmac_last_child(desc);
440 		list_move_tail(&desc->desc_node, list);
441 		/* Make chain-completion interrupt happen */
442 		if ((desc->txd.flags & DMA_PREP_INTERRUPT) &&
443 		    !txx9dmac_chan_INTENT(dc))
444 			break;
445 	} while (!list_empty(&dc->queue));
446 }
447 
448 static void txx9dmac_complete_all(struct txx9dmac_chan *dc)
449 {
450 	struct txx9dmac_desc *desc, *_desc;
451 	LIST_HEAD(list);
452 
453 	/*
454 	 * Submit queued descriptors ASAP, i.e. before we go through
455 	 * the completed ones.
456 	 */
457 	list_splice_init(&dc->active_list, &list);
458 	if (!list_empty(&dc->queue)) {
459 		txx9dmac_dequeue(dc, &dc->active_list);
460 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
461 	}
462 
463 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
464 		txx9dmac_descriptor_complete(dc, desc);
465 }
466 
467 static void txx9dmac_dump_desc(struct txx9dmac_chan *dc,
468 			       struct txx9dmac_hwdesc *desc)
469 {
470 	if (is_dmac64(dc)) {
471 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
472 		dev_crit(chan2dev(&dc->chan),
473 			 "  desc: ch%#llx s%#llx d%#llx c%#x\n",
474 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR);
475 #else
476 		dev_crit(chan2dev(&dc->chan),
477 			 "  desc: ch%#llx s%#llx d%#llx c%#x"
478 			 " si%#x di%#x cc%#x cs%#x\n",
479 			 (u64)desc->CHAR, desc->SAR, desc->DAR, desc->CNTR,
480 			 desc->SAIR, desc->DAIR, desc->CCR, desc->CSR);
481 #endif
482 	} else {
483 		struct txx9dmac_hwdesc32 *d = (struct txx9dmac_hwdesc32 *)desc;
484 #ifdef TXX9_DMA_USE_SIMPLE_CHAIN
485 		dev_crit(chan2dev(&dc->chan),
486 			 "  desc: ch%#x s%#x d%#x c%#x\n",
487 			 d->CHAR, d->SAR, d->DAR, d->CNTR);
488 #else
489 		dev_crit(chan2dev(&dc->chan),
490 			 "  desc: ch%#x s%#x d%#x c%#x"
491 			 " si%#x di%#x cc%#x cs%#x\n",
492 			 d->CHAR, d->SAR, d->DAR, d->CNTR,
493 			 d->SAIR, d->DAIR, d->CCR, d->CSR);
494 #endif
495 	}
496 }
497 
498 static void txx9dmac_handle_error(struct txx9dmac_chan *dc, u32 csr)
499 {
500 	struct txx9dmac_desc *bad_desc;
501 	struct txx9dmac_desc *child;
502 	u32 errors;
503 
504 	/*
505 	 * The descriptor currently at the head of the active list is
506 	 * borked. Since we don't have any way to report errors, we'll
507 	 * just have to scream loudly and try to carry on.
508 	 */
509 	dev_crit(chan2dev(&dc->chan), "Abnormal Chain Completion\n");
510 	txx9dmac_dump_regs(dc);
511 
512 	bad_desc = txx9dmac_first_active(dc);
513 	list_del_init(&bad_desc->desc_node);
514 
515 	/* Clear all error flags and try to restart the controller */
516 	errors = csr & (TXX9_DMA_CSR_ABCHC |
517 			TXX9_DMA_CSR_CFERR | TXX9_DMA_CSR_CHERR |
518 			TXX9_DMA_CSR_DESERR | TXX9_DMA_CSR_SORERR);
519 	channel_writel(dc, CSR, errors);
520 
521 	if (list_empty(&dc->active_list) && !list_empty(&dc->queue))
522 		txx9dmac_dequeue(dc, &dc->active_list);
523 	if (!list_empty(&dc->active_list))
524 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
525 
526 	dev_crit(chan2dev(&dc->chan),
527 		 "Bad descriptor submitted for DMA! (cookie: %d)\n",
528 		 bad_desc->txd.cookie);
529 	txx9dmac_dump_desc(dc, &bad_desc->hwdesc);
530 	list_for_each_entry(child, &bad_desc->tx_list, desc_node)
531 		txx9dmac_dump_desc(dc, &child->hwdesc);
532 	/* Pretend the descriptor completed successfully */
533 	txx9dmac_descriptor_complete(dc, bad_desc);
534 }
535 
536 static void txx9dmac_scan_descriptors(struct txx9dmac_chan *dc)
537 {
538 	dma_addr_t chain;
539 	struct txx9dmac_desc *desc, *_desc;
540 	struct txx9dmac_desc *child;
541 	u32 csr;
542 
543 	if (is_dmac64(dc)) {
544 		chain = channel64_read_CHAR(dc);
545 		csr = channel64_readl(dc, CSR);
546 		channel64_writel(dc, CSR, csr);
547 	} else {
548 		chain = channel32_readl(dc, CHAR);
549 		csr = channel32_readl(dc, CSR);
550 		channel32_writel(dc, CSR, csr);
551 	}
552 	/* For dynamic chain, we should look at XFACT instead of NCHNC */
553 	if (!(csr & (TXX9_DMA_CSR_XFACT | TXX9_DMA_CSR_ABCHC))) {
554 		/* Everything we've submitted is done */
555 		txx9dmac_complete_all(dc);
556 		return;
557 	}
558 	if (!(csr & TXX9_DMA_CSR_CHNEN))
559 		chain = 0;	/* last descriptor of this chain */
560 
561 	dev_vdbg(chan2dev(&dc->chan), "scan_descriptors: char=%#llx\n",
562 		 (u64)chain);
563 
564 	list_for_each_entry_safe(desc, _desc, &dc->active_list, desc_node) {
565 		if (desc_read_CHAR(dc, desc) == chain) {
566 			/* This one is currently in progress */
567 			if (csr & TXX9_DMA_CSR_ABCHC)
568 				goto scan_done;
569 			return;
570 		}
571 
572 		list_for_each_entry(child, &desc->tx_list, desc_node)
573 			if (desc_read_CHAR(dc, child) == chain) {
574 				/* Currently in progress */
575 				if (csr & TXX9_DMA_CSR_ABCHC)
576 					goto scan_done;
577 				return;
578 			}
579 
580 		/*
581 		 * No descriptors so far seem to be in progress, i.e.
582 		 * this one must be done.
583 		 */
584 		txx9dmac_descriptor_complete(dc, desc);
585 	}
586 scan_done:
587 	if (csr & TXX9_DMA_CSR_ABCHC) {
588 		txx9dmac_handle_error(dc, csr);
589 		return;
590 	}
591 
592 	dev_err(chan2dev(&dc->chan),
593 		"BUG: All descriptors done, but channel not idle!\n");
594 
595 	/* Try to continue after resetting the channel... */
596 	txx9dmac_reset_chan(dc);
597 
598 	if (!list_empty(&dc->queue)) {
599 		txx9dmac_dequeue(dc, &dc->active_list);
600 		txx9dmac_dostart(dc, txx9dmac_first_active(dc));
601 	}
602 }
603 
604 static void txx9dmac_chan_tasklet(struct tasklet_struct *t)
605 {
606 	int irq;
607 	u32 csr;
608 	struct txx9dmac_chan *dc;
609 
610 	dc = from_tasklet(dc, t, tasklet);
611 	csr = channel_readl(dc, CSR);
612 	dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n", csr);
613 
614 	spin_lock(&dc->lock);
615 	if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
616 		   TXX9_DMA_CSR_NTRNFC))
617 		txx9dmac_scan_descriptors(dc);
618 	spin_unlock(&dc->lock);
619 	irq = dc->irq;
620 
621 	enable_irq(irq);
622 }
623 
624 static irqreturn_t txx9dmac_chan_interrupt(int irq, void *dev_id)
625 {
626 	struct txx9dmac_chan *dc = dev_id;
627 
628 	dev_vdbg(chan2dev(&dc->chan), "interrupt: status=%#x\n",
629 			channel_readl(dc, CSR));
630 
631 	tasklet_schedule(&dc->tasklet);
632 	/*
633 	 * Just disable the interrupts. We'll turn them back on in the
634 	 * softirq handler.
635 	 */
636 	disable_irq_nosync(irq);
637 
638 	return IRQ_HANDLED;
639 }
640 
641 static void txx9dmac_tasklet(struct tasklet_struct *t)
642 {
643 	int irq;
644 	u32 csr;
645 	struct txx9dmac_chan *dc;
646 
647 	struct txx9dmac_dev *ddev = from_tasklet(ddev, t, tasklet);
648 	u32 mcr;
649 	int i;
650 
651 	mcr = dma_readl(ddev, MCR);
652 	dev_vdbg(ddev->chan[0]->dma.dev, "tasklet: mcr=%x\n", mcr);
653 	for (i = 0; i < TXX9_DMA_MAX_NR_CHANNELS; i++) {
654 		if ((mcr >> (24 + i)) & 0x11) {
655 			dc = ddev->chan[i];
656 			csr = channel_readl(dc, CSR);
657 			dev_vdbg(chan2dev(&dc->chan), "tasklet: status=%x\n",
658 				 csr);
659 			spin_lock(&dc->lock);
660 			if (csr & (TXX9_DMA_CSR_ABCHC | TXX9_DMA_CSR_NCHNC |
661 				   TXX9_DMA_CSR_NTRNFC))
662 				txx9dmac_scan_descriptors(dc);
663 			spin_unlock(&dc->lock);
664 		}
665 	}
666 	irq = ddev->irq;
667 
668 	enable_irq(irq);
669 }
670 
671 static irqreturn_t txx9dmac_interrupt(int irq, void *dev_id)
672 {
673 	struct txx9dmac_dev *ddev = dev_id;
674 
675 	dev_vdbg(ddev->chan[0]->dma.dev, "interrupt: status=%#x\n",
676 			dma_readl(ddev, MCR));
677 
678 	tasklet_schedule(&ddev->tasklet);
679 	/*
680 	 * Just disable the interrupts. We'll turn them back on in the
681 	 * softirq handler.
682 	 */
683 	disable_irq_nosync(irq);
684 
685 	return IRQ_HANDLED;
686 }
687 
688 /*----------------------------------------------------------------------*/
689 
690 static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx)
691 {
692 	struct txx9dmac_desc *desc = txd_to_txx9dmac_desc(tx);
693 	struct txx9dmac_chan *dc = to_txx9dmac_chan(tx->chan);
694 	dma_cookie_t cookie;
695 
696 	spin_lock_bh(&dc->lock);
697 	cookie = dma_cookie_assign(tx);
698 
699 	dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u %p\n",
700 		 desc->txd.cookie, desc);
701 
702 	list_add_tail(&desc->desc_node, &dc->queue);
703 	spin_unlock_bh(&dc->lock);
704 
705 	return cookie;
706 }
707 
708 static struct dma_async_tx_descriptor *
709 txx9dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
710 		size_t len, unsigned long flags)
711 {
712 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
713 	struct txx9dmac_dev *ddev = dc->ddev;
714 	struct txx9dmac_desc *desc;
715 	struct txx9dmac_desc *first;
716 	struct txx9dmac_desc *prev;
717 	size_t xfer_count;
718 	size_t offset;
719 
720 	dev_vdbg(chan2dev(chan), "prep_dma_memcpy d%#llx s%#llx l%#zx f%#lx\n",
721 		 (u64)dest, (u64)src, len, flags);
722 
723 	if (unlikely(!len)) {
724 		dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n");
725 		return NULL;
726 	}
727 
728 	prev = first = NULL;
729 
730 	for (offset = 0; offset < len; offset += xfer_count) {
731 		xfer_count = min_t(size_t, len - offset, TXX9_DMA_MAX_COUNT);
732 		/*
733 		 * Workaround for ERT-TX49H2-033, ERT-TX49H3-020,
734 		 * ERT-TX49H4-016 (slightly conservative)
735 		 */
736 		if (__is_dmac64(ddev)) {
737 			if (xfer_count > 0x100 &&
738 			    (xfer_count & 0xff) >= 0xfa &&
739 			    (xfer_count & 0xff) <= 0xff)
740 				xfer_count -= 0x20;
741 		} else {
742 			if (xfer_count > 0x80 &&
743 			    (xfer_count & 0x7f) >= 0x7e &&
744 			    (xfer_count & 0x7f) <= 0x7f)
745 				xfer_count -= 0x20;
746 		}
747 
748 		desc = txx9dmac_desc_get(dc);
749 		if (!desc) {
750 			txx9dmac_desc_put(dc, first);
751 			return NULL;
752 		}
753 
754 		if (__is_dmac64(ddev)) {
755 			desc->hwdesc.SAR = src + offset;
756 			desc->hwdesc.DAR = dest + offset;
757 			desc->hwdesc.CNTR = xfer_count;
758 			txx9dmac_desc_set_nosimple(ddev, desc, 8, 8,
759 					dc->ccr | TXX9_DMA_CCR_XFACT);
760 		} else {
761 			desc->hwdesc32.SAR = src + offset;
762 			desc->hwdesc32.DAR = dest + offset;
763 			desc->hwdesc32.CNTR = xfer_count;
764 			txx9dmac_desc_set_nosimple(ddev, desc, 4, 4,
765 					dc->ccr | TXX9_DMA_CCR_XFACT);
766 		}
767 
768 		/*
769 		 * The descriptors on tx_list are not reachable from
770 		 * the dc->queue list or dc->active_list after a
771 		 * submit.  If we put all descriptors on active_list,
772 		 * calling of callback on the completion will be more
773 		 * complex.
774 		 */
775 		if (!first) {
776 			first = desc;
777 		} else {
778 			desc_write_CHAR(dc, prev, desc->txd.phys);
779 			dma_sync_single_for_device(chan2parent(&dc->chan),
780 					prev->txd.phys, ddev->descsize,
781 					DMA_TO_DEVICE);
782 			list_add_tail(&desc->desc_node, &first->tx_list);
783 		}
784 		prev = desc;
785 	}
786 
787 	/* Trigger interrupt after last block */
788 	if (flags & DMA_PREP_INTERRUPT)
789 		txx9dmac_desc_set_INTENT(ddev, prev);
790 
791 	desc_write_CHAR(dc, prev, 0);
792 	dma_sync_single_for_device(chan2parent(&dc->chan),
793 			prev->txd.phys, ddev->descsize,
794 			DMA_TO_DEVICE);
795 
796 	first->txd.flags = flags;
797 	first->len = len;
798 
799 	return &first->txd;
800 }
801 
802 static struct dma_async_tx_descriptor *
803 txx9dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
804 		unsigned int sg_len, enum dma_transfer_direction direction,
805 		unsigned long flags, void *context)
806 {
807 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
808 	struct txx9dmac_dev *ddev = dc->ddev;
809 	struct txx9dmac_slave *ds = chan->private;
810 	struct txx9dmac_desc *prev;
811 	struct txx9dmac_desc *first;
812 	unsigned int i;
813 	struct scatterlist *sg;
814 
815 	dev_vdbg(chan2dev(chan), "prep_dma_slave\n");
816 
817 	BUG_ON(!ds || !ds->reg_width);
818 	if (ds->tx_reg)
819 		BUG_ON(direction != DMA_MEM_TO_DEV);
820 	else
821 		BUG_ON(direction != DMA_DEV_TO_MEM);
822 	if (unlikely(!sg_len))
823 		return NULL;
824 
825 	prev = first = NULL;
826 
827 	for_each_sg(sgl, sg, sg_len, i) {
828 		struct txx9dmac_desc *desc;
829 		dma_addr_t mem;
830 		u32 sai, dai;
831 
832 		desc = txx9dmac_desc_get(dc);
833 		if (!desc) {
834 			txx9dmac_desc_put(dc, first);
835 			return NULL;
836 		}
837 
838 		mem = sg_dma_address(sg);
839 
840 		if (__is_dmac64(ddev)) {
841 			if (direction == DMA_MEM_TO_DEV) {
842 				desc->hwdesc.SAR = mem;
843 				desc->hwdesc.DAR = ds->tx_reg;
844 			} else {
845 				desc->hwdesc.SAR = ds->rx_reg;
846 				desc->hwdesc.DAR = mem;
847 			}
848 			desc->hwdesc.CNTR = sg_dma_len(sg);
849 		} else {
850 			if (direction == DMA_MEM_TO_DEV) {
851 				desc->hwdesc32.SAR = mem;
852 				desc->hwdesc32.DAR = ds->tx_reg;
853 			} else {
854 				desc->hwdesc32.SAR = ds->rx_reg;
855 				desc->hwdesc32.DAR = mem;
856 			}
857 			desc->hwdesc32.CNTR = sg_dma_len(sg);
858 		}
859 		if (direction == DMA_MEM_TO_DEV) {
860 			sai = ds->reg_width;
861 			dai = 0;
862 		} else {
863 			sai = 0;
864 			dai = ds->reg_width;
865 		}
866 		txx9dmac_desc_set_nosimple(ddev, desc, sai, dai,
867 					dc->ccr | TXX9_DMA_CCR_XFACT);
868 
869 		if (!first) {
870 			first = desc;
871 		} else {
872 			desc_write_CHAR(dc, prev, desc->txd.phys);
873 			dma_sync_single_for_device(chan2parent(&dc->chan),
874 					prev->txd.phys,
875 					ddev->descsize,
876 					DMA_TO_DEVICE);
877 			list_add_tail(&desc->desc_node, &first->tx_list);
878 		}
879 		prev = desc;
880 	}
881 
882 	/* Trigger interrupt after last block */
883 	if (flags & DMA_PREP_INTERRUPT)
884 		txx9dmac_desc_set_INTENT(ddev, prev);
885 
886 	desc_write_CHAR(dc, prev, 0);
887 	dma_sync_single_for_device(chan2parent(&dc->chan),
888 			prev->txd.phys, ddev->descsize,
889 			DMA_TO_DEVICE);
890 
891 	first->txd.flags = flags;
892 	first->len = 0;
893 
894 	return &first->txd;
895 }
896 
897 static int txx9dmac_terminate_all(struct dma_chan *chan)
898 {
899 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
900 	struct txx9dmac_desc *desc, *_desc;
901 	LIST_HEAD(list);
902 
903 	dev_vdbg(chan2dev(chan), "terminate_all\n");
904 	spin_lock_bh(&dc->lock);
905 
906 	txx9dmac_reset_chan(dc);
907 
908 	/* active_list entries will end up before queued entries */
909 	list_splice_init(&dc->queue, &list);
910 	list_splice_init(&dc->active_list, &list);
911 
912 	spin_unlock_bh(&dc->lock);
913 
914 	/* Flush all pending and queued descriptors */
915 	list_for_each_entry_safe(desc, _desc, &list, desc_node)
916 		txx9dmac_descriptor_complete(dc, desc);
917 
918 	return 0;
919 }
920 
921 static enum dma_status
922 txx9dmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
923 		   struct dma_tx_state *txstate)
924 {
925 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
926 	enum dma_status ret;
927 
928 	ret = dma_cookie_status(chan, cookie, txstate);
929 	if (ret == DMA_COMPLETE)
930 		return DMA_COMPLETE;
931 
932 	spin_lock_bh(&dc->lock);
933 	txx9dmac_scan_descriptors(dc);
934 	spin_unlock_bh(&dc->lock);
935 
936 	return dma_cookie_status(chan, cookie, txstate);
937 }
938 
939 static void txx9dmac_chain_dynamic(struct txx9dmac_chan *dc,
940 				   struct txx9dmac_desc *prev)
941 {
942 	struct txx9dmac_dev *ddev = dc->ddev;
943 	struct txx9dmac_desc *desc;
944 	LIST_HEAD(list);
945 
946 	prev = txx9dmac_last_child(prev);
947 	txx9dmac_dequeue(dc, &list);
948 	desc = list_entry(list.next, struct txx9dmac_desc, desc_node);
949 	desc_write_CHAR(dc, prev, desc->txd.phys);
950 	dma_sync_single_for_device(chan2parent(&dc->chan),
951 				   prev->txd.phys, ddev->descsize,
952 				   DMA_TO_DEVICE);
953 	if (!(channel_readl(dc, CSR) & TXX9_DMA_CSR_CHNEN) &&
954 	    channel_read_CHAR(dc) == prev->txd.phys)
955 		/* Restart chain DMA */
956 		channel_write_CHAR(dc, desc->txd.phys);
957 	list_splice_tail(&list, &dc->active_list);
958 }
959 
960 static void txx9dmac_issue_pending(struct dma_chan *chan)
961 {
962 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
963 
964 	spin_lock_bh(&dc->lock);
965 
966 	if (!list_empty(&dc->active_list))
967 		txx9dmac_scan_descriptors(dc);
968 	if (!list_empty(&dc->queue)) {
969 		if (list_empty(&dc->active_list)) {
970 			txx9dmac_dequeue(dc, &dc->active_list);
971 			txx9dmac_dostart(dc, txx9dmac_first_active(dc));
972 		} else if (txx9_dma_have_SMPCHN()) {
973 			struct txx9dmac_desc *prev = txx9dmac_last_active(dc);
974 
975 			if (!(prev->txd.flags & DMA_PREP_INTERRUPT) ||
976 			    txx9dmac_chan_INTENT(dc))
977 				txx9dmac_chain_dynamic(dc, prev);
978 		}
979 	}
980 
981 	spin_unlock_bh(&dc->lock);
982 }
983 
984 static int txx9dmac_alloc_chan_resources(struct dma_chan *chan)
985 {
986 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
987 	struct txx9dmac_slave *ds = chan->private;
988 	struct txx9dmac_desc *desc;
989 	int i;
990 
991 	dev_vdbg(chan2dev(chan), "alloc_chan_resources\n");
992 
993 	/* ASSERT:  channel is idle */
994 	if (channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT) {
995 		dev_dbg(chan2dev(chan), "DMA channel not idle?\n");
996 		return -EIO;
997 	}
998 
999 	dma_cookie_init(chan);
1000 
1001 	dc->ccr = TXX9_DMA_CCR_IMMCHN | TXX9_DMA_CCR_INTENE | CCR_LE;
1002 	txx9dmac_chan_set_SMPCHN(dc);
1003 	if (!txx9_dma_have_SMPCHN() || (dc->ccr & TXX9_DMA_CCR_SMPCHN))
1004 		dc->ccr |= TXX9_DMA_CCR_INTENC;
1005 	if (chan->device->device_prep_dma_memcpy) {
1006 		if (ds)
1007 			return -EINVAL;
1008 		dc->ccr |= TXX9_DMA_CCR_XFSZ_X8;
1009 	} else {
1010 		if (!ds ||
1011 		    (ds->tx_reg && ds->rx_reg) || (!ds->tx_reg && !ds->rx_reg))
1012 			return -EINVAL;
1013 		dc->ccr |= TXX9_DMA_CCR_EXTRQ |
1014 			TXX9_DMA_CCR_XFSZ(__ffs(ds->reg_width));
1015 		txx9dmac_chan_set_INTENT(dc);
1016 	}
1017 
1018 	spin_lock_bh(&dc->lock);
1019 	i = dc->descs_allocated;
1020 	while (dc->descs_allocated < TXX9_DMA_INITIAL_DESC_COUNT) {
1021 		spin_unlock_bh(&dc->lock);
1022 
1023 		desc = txx9dmac_desc_alloc(dc, GFP_KERNEL);
1024 		if (!desc) {
1025 			dev_info(chan2dev(chan),
1026 				"only allocated %d descriptors\n", i);
1027 			spin_lock_bh(&dc->lock);
1028 			break;
1029 		}
1030 		txx9dmac_desc_put(dc, desc);
1031 
1032 		spin_lock_bh(&dc->lock);
1033 		i = ++dc->descs_allocated;
1034 	}
1035 	spin_unlock_bh(&dc->lock);
1036 
1037 	dev_dbg(chan2dev(chan),
1038 		"alloc_chan_resources allocated %d descriptors\n", i);
1039 
1040 	return i;
1041 }
1042 
1043 static void txx9dmac_free_chan_resources(struct dma_chan *chan)
1044 {
1045 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
1046 	struct txx9dmac_dev *ddev = dc->ddev;
1047 	struct txx9dmac_desc *desc, *_desc;
1048 	LIST_HEAD(list);
1049 
1050 	dev_dbg(chan2dev(chan), "free_chan_resources (descs allocated=%u)\n",
1051 			dc->descs_allocated);
1052 
1053 	/* ASSERT:  channel is idle */
1054 	BUG_ON(!list_empty(&dc->active_list));
1055 	BUG_ON(!list_empty(&dc->queue));
1056 	BUG_ON(channel_readl(dc, CSR) & TXX9_DMA_CSR_XFACT);
1057 
1058 	spin_lock_bh(&dc->lock);
1059 	list_splice_init(&dc->free_list, &list);
1060 	dc->descs_allocated = 0;
1061 	spin_unlock_bh(&dc->lock);
1062 
1063 	list_for_each_entry_safe(desc, _desc, &list, desc_node) {
1064 		dev_vdbg(chan2dev(chan), "  freeing descriptor %p\n", desc);
1065 		dma_unmap_single(chan2parent(chan), desc->txd.phys,
1066 				 ddev->descsize, DMA_TO_DEVICE);
1067 		kfree(desc);
1068 	}
1069 
1070 	dev_vdbg(chan2dev(chan), "free_chan_resources done\n");
1071 }
1072 
1073 /*----------------------------------------------------------------------*/
1074 
1075 static void txx9dmac_off(struct txx9dmac_dev *ddev)
1076 {
1077 	dma_writel(ddev, MCR, 0);
1078 }
1079 
1080 static int __init txx9dmac_chan_probe(struct platform_device *pdev)
1081 {
1082 	struct txx9dmac_chan_platform_data *cpdata =
1083 			dev_get_platdata(&pdev->dev);
1084 	struct platform_device *dmac_dev = cpdata->dmac_dev;
1085 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&dmac_dev->dev);
1086 	struct txx9dmac_chan *dc;
1087 	int err;
1088 	int ch = pdev->id % TXX9_DMA_MAX_NR_CHANNELS;
1089 	int irq;
1090 
1091 	dc = devm_kzalloc(&pdev->dev, sizeof(*dc), GFP_KERNEL);
1092 	if (!dc)
1093 		return -ENOMEM;
1094 
1095 	dc->dma.dev = &pdev->dev;
1096 	dc->dma.device_alloc_chan_resources = txx9dmac_alloc_chan_resources;
1097 	dc->dma.device_free_chan_resources = txx9dmac_free_chan_resources;
1098 	dc->dma.device_terminate_all = txx9dmac_terminate_all;
1099 	dc->dma.device_tx_status = txx9dmac_tx_status;
1100 	dc->dma.device_issue_pending = txx9dmac_issue_pending;
1101 	if (pdata && pdata->memcpy_chan == ch) {
1102 		dc->dma.device_prep_dma_memcpy = txx9dmac_prep_dma_memcpy;
1103 		dma_cap_set(DMA_MEMCPY, dc->dma.cap_mask);
1104 	} else {
1105 		dc->dma.device_prep_slave_sg = txx9dmac_prep_slave_sg;
1106 		dma_cap_set(DMA_SLAVE, dc->dma.cap_mask);
1107 		dma_cap_set(DMA_PRIVATE, dc->dma.cap_mask);
1108 	}
1109 
1110 	INIT_LIST_HEAD(&dc->dma.channels);
1111 	dc->ddev = platform_get_drvdata(dmac_dev);
1112 	if (dc->ddev->irq < 0) {
1113 		irq = platform_get_irq(pdev, 0);
1114 		if (irq < 0)
1115 			return irq;
1116 		tasklet_setup(&dc->tasklet, txx9dmac_chan_tasklet);
1117 		dc->irq = irq;
1118 		err = devm_request_irq(&pdev->dev, dc->irq,
1119 			txx9dmac_chan_interrupt, 0, dev_name(&pdev->dev), dc);
1120 		if (err)
1121 			return err;
1122 	} else
1123 		dc->irq = -1;
1124 	dc->ddev->chan[ch] = dc;
1125 	dc->chan.device = &dc->dma;
1126 	list_add_tail(&dc->chan.device_node, &dc->chan.device->channels);
1127 	dma_cookie_init(&dc->chan);
1128 
1129 	if (is_dmac64(dc))
1130 		dc->ch_regs = &__txx9dmac_regs(dc->ddev)->CHAN[ch];
1131 	else
1132 		dc->ch_regs = &__txx9dmac_regs32(dc->ddev)->CHAN[ch];
1133 	spin_lock_init(&dc->lock);
1134 
1135 	INIT_LIST_HEAD(&dc->active_list);
1136 	INIT_LIST_HEAD(&dc->queue);
1137 	INIT_LIST_HEAD(&dc->free_list);
1138 
1139 	txx9dmac_reset_chan(dc);
1140 
1141 	platform_set_drvdata(pdev, dc);
1142 
1143 	err = dma_async_device_register(&dc->dma);
1144 	if (err)
1145 		return err;
1146 	dev_dbg(&pdev->dev, "TXx9 DMA Channel (dma%d%s%s)\n",
1147 		dc->dma.dev_id,
1148 		dma_has_cap(DMA_MEMCPY, dc->dma.cap_mask) ? " memcpy" : "",
1149 		dma_has_cap(DMA_SLAVE, dc->dma.cap_mask) ? " slave" : "");
1150 
1151 	return 0;
1152 }
1153 
1154 static int txx9dmac_chan_remove(struct platform_device *pdev)
1155 {
1156 	struct txx9dmac_chan *dc = platform_get_drvdata(pdev);
1157 
1158 
1159 	dma_async_device_unregister(&dc->dma);
1160 	if (dc->irq >= 0) {
1161 		devm_free_irq(&pdev->dev, dc->irq, dc);
1162 		tasklet_kill(&dc->tasklet);
1163 	}
1164 	dc->ddev->chan[pdev->id % TXX9_DMA_MAX_NR_CHANNELS] = NULL;
1165 	return 0;
1166 }
1167 
1168 static int __init txx9dmac_probe(struct platform_device *pdev)
1169 {
1170 	struct txx9dmac_platform_data *pdata = dev_get_platdata(&pdev->dev);
1171 	struct resource *io;
1172 	struct txx9dmac_dev *ddev;
1173 	u32 mcr;
1174 	int err;
1175 
1176 	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1177 	if (!io)
1178 		return -EINVAL;
1179 
1180 	ddev = devm_kzalloc(&pdev->dev, sizeof(*ddev), GFP_KERNEL);
1181 	if (!ddev)
1182 		return -ENOMEM;
1183 
1184 	if (!devm_request_mem_region(&pdev->dev, io->start, resource_size(io),
1185 				     dev_name(&pdev->dev)))
1186 		return -EBUSY;
1187 
1188 	ddev->regs = devm_ioremap(&pdev->dev, io->start, resource_size(io));
1189 	if (!ddev->regs)
1190 		return -ENOMEM;
1191 	ddev->have_64bit_regs = pdata->have_64bit_regs;
1192 	if (__is_dmac64(ddev))
1193 		ddev->descsize = sizeof(struct txx9dmac_hwdesc);
1194 	else
1195 		ddev->descsize = sizeof(struct txx9dmac_hwdesc32);
1196 
1197 	/* force dma off, just in case */
1198 	txx9dmac_off(ddev);
1199 
1200 	ddev->irq = platform_get_irq(pdev, 0);
1201 	if (ddev->irq >= 0) {
1202 		tasklet_setup(&ddev->tasklet, txx9dmac_tasklet);
1203 		err = devm_request_irq(&pdev->dev, ddev->irq,
1204 			txx9dmac_interrupt, 0, dev_name(&pdev->dev), ddev);
1205 		if (err)
1206 			return err;
1207 	}
1208 
1209 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1210 	if (pdata && pdata->memcpy_chan >= 0)
1211 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1212 	dma_writel(ddev, MCR, mcr);
1213 
1214 	platform_set_drvdata(pdev, ddev);
1215 	return 0;
1216 }
1217 
1218 static int txx9dmac_remove(struct platform_device *pdev)
1219 {
1220 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1221 
1222 	txx9dmac_off(ddev);
1223 	if (ddev->irq >= 0) {
1224 		devm_free_irq(&pdev->dev, ddev->irq, ddev);
1225 		tasklet_kill(&ddev->tasklet);
1226 	}
1227 	return 0;
1228 }
1229 
1230 static void txx9dmac_shutdown(struct platform_device *pdev)
1231 {
1232 	struct txx9dmac_dev *ddev = platform_get_drvdata(pdev);
1233 
1234 	txx9dmac_off(ddev);
1235 }
1236 
1237 static int txx9dmac_suspend_noirq(struct device *dev)
1238 {
1239 	struct txx9dmac_dev *ddev = dev_get_drvdata(dev);
1240 
1241 	txx9dmac_off(ddev);
1242 	return 0;
1243 }
1244 
1245 static int txx9dmac_resume_noirq(struct device *dev)
1246 {
1247 	struct txx9dmac_dev *ddev = dev_get_drvdata(dev);
1248 	struct txx9dmac_platform_data *pdata = dev_get_platdata(dev);
1249 	u32 mcr;
1250 
1251 	mcr = TXX9_DMA_MCR_MSTEN | MCR_LE;
1252 	if (pdata && pdata->memcpy_chan >= 0)
1253 		mcr |= TXX9_DMA_MCR_FIFUM(pdata->memcpy_chan);
1254 	dma_writel(ddev, MCR, mcr);
1255 	return 0;
1256 
1257 }
1258 
1259 static const struct dev_pm_ops txx9dmac_dev_pm_ops = {
1260 	.suspend_noirq = txx9dmac_suspend_noirq,
1261 	.resume_noirq = txx9dmac_resume_noirq,
1262 };
1263 
1264 static struct platform_driver txx9dmac_chan_driver = {
1265 	.remove		= txx9dmac_chan_remove,
1266 	.driver = {
1267 		.name	= "txx9dmac-chan",
1268 	},
1269 };
1270 
1271 static struct platform_driver txx9dmac_driver = {
1272 	.remove		= txx9dmac_remove,
1273 	.shutdown	= txx9dmac_shutdown,
1274 	.driver = {
1275 		.name	= "txx9dmac",
1276 		.pm	= &txx9dmac_dev_pm_ops,
1277 	},
1278 };
1279 
1280 static int __init txx9dmac_init(void)
1281 {
1282 	int rc;
1283 
1284 	rc = platform_driver_probe(&txx9dmac_driver, txx9dmac_probe);
1285 	if (!rc) {
1286 		rc = platform_driver_probe(&txx9dmac_chan_driver,
1287 					   txx9dmac_chan_probe);
1288 		if (rc)
1289 			platform_driver_unregister(&txx9dmac_driver);
1290 	}
1291 	return rc;
1292 }
1293 module_init(txx9dmac_init);
1294 
1295 static void __exit txx9dmac_exit(void)
1296 {
1297 	platform_driver_unregister(&txx9dmac_chan_driver);
1298 	platform_driver_unregister(&txx9dmac_driver);
1299 }
1300 module_exit(txx9dmac_exit);
1301 
1302 MODULE_LICENSE("GPL");
1303 MODULE_DESCRIPTION("TXx9 DMA Controller driver");
1304 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
1305 MODULE_ALIAS("platform:txx9dmac");
1306 MODULE_ALIAS("platform:txx9dmac-chan");
1307