xref: /openbmc/linux/drivers/dma/sh/shdmac.c (revision b96fc2f3)
1 /*
2  * Renesas SuperH DMA Engine support
3  *
4  * base is drivers/dma/flsdma.c
5  *
6  * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
7  * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
8  * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
9  * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
10  *
11  * This is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * - DMA of SuperH does not have Hardware DMA chain mode.
17  * - MAX DMA size is 16MB.
18  *
19  */
20 
21 #include <linux/delay.h>
22 #include <linux/dmaengine.h>
23 #include <linux/err.h>
24 #include <linux/init.h>
25 #include <linux/interrupt.h>
26 #include <linux/kdebug.h>
27 #include <linux/module.h>
28 #include <linux/notifier.h>
29 #include <linux/of.h>
30 #include <linux/of_device.h>
31 #include <linux/platform_device.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/rculist.h>
34 #include <linux/sh_dma.h>
35 #include <linux/slab.h>
36 #include <linux/spinlock.h>
37 
38 #include "../dmaengine.h"
39 #include "shdma.h"
40 
41 /* DMA registers */
42 #define SAR	0x00	/* Source Address Register */
43 #define DAR	0x04	/* Destination Address Register */
44 #define TCR	0x08	/* Transfer Count Register */
45 #define CHCR	0x0C	/* Channel Control Register */
46 #define DMAOR	0x40	/* DMA Operation Register */
47 
48 #define TEND	0x18 /* USB-DMAC */
49 
50 #define SH_DMAE_DRV_NAME "sh-dma-engine"
51 
52 /* Default MEMCPY transfer size = 2^2 = 4 bytes */
53 #define LOG2_DEFAULT_XFER_SIZE	2
54 #define SH_DMA_SLAVE_NUMBER 256
55 #define SH_DMA_TCR_MAX (16 * 1024 * 1024 - 1)
56 
57 /*
58  * Used for write-side mutual exclusion for the global device list,
59  * read-side synchronization by way of RCU, and per-controller data.
60  */
61 static DEFINE_SPINLOCK(sh_dmae_lock);
62 static LIST_HEAD(sh_dmae_devices);
63 
64 /*
65  * Different DMAC implementations provide different ways to clear DMA channels:
66  * (1) none - no CHCLR registers are available
67  * (2) one CHCLR register per channel - 0 has to be written to it to clear
68  *     channel buffers
69  * (3) one CHCLR per several channels - 1 has to be written to the bit,
70  *     corresponding to the specific channel to reset it
71  */
72 static void channel_clear(struct sh_dmae_chan *sh_dc)
73 {
74 	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
75 	const struct sh_dmae_channel *chan_pdata = shdev->pdata->channel +
76 		sh_dc->shdma_chan.id;
77 	u32 val = shdev->pdata->chclr_bitwise ? 1 << chan_pdata->chclr_bit : 0;
78 
79 	__raw_writel(val, shdev->chan_reg + chan_pdata->chclr_offset);
80 }
81 
82 static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
83 {
84 	__raw_writel(data, sh_dc->base + reg);
85 }
86 
87 static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
88 {
89 	return __raw_readl(sh_dc->base + reg);
90 }
91 
92 static u16 dmaor_read(struct sh_dmae_device *shdev)
93 {
94 	void __iomem *addr = shdev->chan_reg + DMAOR;
95 
96 	if (shdev->pdata->dmaor_is_32bit)
97 		return __raw_readl(addr);
98 	else
99 		return __raw_readw(addr);
100 }
101 
102 static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
103 {
104 	void __iomem *addr = shdev->chan_reg + DMAOR;
105 
106 	if (shdev->pdata->dmaor_is_32bit)
107 		__raw_writel(data, addr);
108 	else
109 		__raw_writew(data, addr);
110 }
111 
112 static void chcr_write(struct sh_dmae_chan *sh_dc, u32 data)
113 {
114 	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
115 
116 	__raw_writel(data, sh_dc->base + shdev->chcr_offset);
117 }
118 
119 static u32 chcr_read(struct sh_dmae_chan *sh_dc)
120 {
121 	struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
122 
123 	return __raw_readl(sh_dc->base + shdev->chcr_offset);
124 }
125 
126 /*
127  * Reset DMA controller
128  *
129  * SH7780 has two DMAOR register
130  */
131 static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
132 {
133 	unsigned short dmaor;
134 	unsigned long flags;
135 
136 	spin_lock_irqsave(&sh_dmae_lock, flags);
137 
138 	dmaor = dmaor_read(shdev);
139 	dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
140 
141 	spin_unlock_irqrestore(&sh_dmae_lock, flags);
142 }
143 
144 static int sh_dmae_rst(struct sh_dmae_device *shdev)
145 {
146 	unsigned short dmaor;
147 	unsigned long flags;
148 
149 	spin_lock_irqsave(&sh_dmae_lock, flags);
150 
151 	dmaor = dmaor_read(shdev) & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME);
152 
153 	if (shdev->pdata->chclr_present) {
154 		int i;
155 		for (i = 0; i < shdev->pdata->channel_num; i++) {
156 			struct sh_dmae_chan *sh_chan = shdev->chan[i];
157 			if (sh_chan)
158 				channel_clear(sh_chan);
159 		}
160 	}
161 
162 	dmaor_write(shdev, dmaor | shdev->pdata->dmaor_init);
163 
164 	dmaor = dmaor_read(shdev);
165 
166 	spin_unlock_irqrestore(&sh_dmae_lock, flags);
167 
168 	if (dmaor & (DMAOR_AE | DMAOR_NMIF)) {
169 		dev_warn(shdev->shdma_dev.dma_dev.dev, "Can't initialize DMAOR.\n");
170 		return -EIO;
171 	}
172 	if (shdev->pdata->dmaor_init & ~dmaor)
173 		dev_warn(shdev->shdma_dev.dma_dev.dev,
174 			 "DMAOR=0x%x hasn't latched the initial value 0x%x.\n",
175 			 dmaor, shdev->pdata->dmaor_init);
176 	return 0;
177 }
178 
179 static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
180 {
181 	u32 chcr = chcr_read(sh_chan);
182 
183 	if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
184 		return true; /* working */
185 
186 	return false; /* waiting */
187 }
188 
189 static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
190 {
191 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
192 	const struct sh_dmae_pdata *pdata = shdev->pdata;
193 	int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
194 		((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
195 
196 	if (cnt >= pdata->ts_shift_num)
197 		cnt = 0;
198 
199 	return pdata->ts_shift[cnt];
200 }
201 
202 static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
203 {
204 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
205 	const struct sh_dmae_pdata *pdata = shdev->pdata;
206 	int i;
207 
208 	for (i = 0; i < pdata->ts_shift_num; i++)
209 		if (pdata->ts_shift[i] == l2size)
210 			break;
211 
212 	if (i == pdata->ts_shift_num)
213 		i = 0;
214 
215 	return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
216 		((i << pdata->ts_high_shift) & pdata->ts_high_mask);
217 }
218 
219 static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
220 {
221 	sh_dmae_writel(sh_chan, hw->sar, SAR);
222 	sh_dmae_writel(sh_chan, hw->dar, DAR);
223 	sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
224 }
225 
226 static void dmae_start(struct sh_dmae_chan *sh_chan)
227 {
228 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
229 	u32 chcr = chcr_read(sh_chan);
230 
231 	if (shdev->pdata->needs_tend_set)
232 		sh_dmae_writel(sh_chan, 0xFFFFFFFF, TEND);
233 
234 	chcr |= CHCR_DE | shdev->chcr_ie_bit;
235 	chcr_write(sh_chan, chcr & ~CHCR_TE);
236 }
237 
238 static void dmae_init(struct sh_dmae_chan *sh_chan)
239 {
240 	/*
241 	 * Default configuration for dual address memory-memory transfer.
242 	 */
243 	u32 chcr = DM_INC | SM_INC | RS_AUTO | log2size_to_chcr(sh_chan,
244 						   LOG2_DEFAULT_XFER_SIZE);
245 	sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
246 	chcr_write(sh_chan, chcr);
247 }
248 
249 static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
250 {
251 	/* If DMA is active, cannot set CHCR. TODO: remove this superfluous check */
252 	if (dmae_is_busy(sh_chan))
253 		return -EBUSY;
254 
255 	sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
256 	chcr_write(sh_chan, val);
257 
258 	return 0;
259 }
260 
261 static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
262 {
263 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
264 	const struct sh_dmae_pdata *pdata = shdev->pdata;
265 	const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->shdma_chan.id];
266 	void __iomem *addr = shdev->dmars;
267 	unsigned int shift = chan_pdata->dmars_bit;
268 
269 	if (dmae_is_busy(sh_chan))
270 		return -EBUSY;
271 
272 	if (pdata->no_dmars)
273 		return 0;
274 
275 	/* in the case of a missing DMARS resource use first memory window */
276 	if (!addr)
277 		addr = shdev->chan_reg;
278 	addr += chan_pdata->dmars;
279 
280 	__raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
281 		     addr);
282 
283 	return 0;
284 }
285 
286 static void sh_dmae_start_xfer(struct shdma_chan *schan,
287 			       struct shdma_desc *sdesc)
288 {
289 	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
290 						    shdma_chan);
291 	struct sh_dmae_desc *sh_desc = container_of(sdesc,
292 					struct sh_dmae_desc, shdma_desc);
293 	dev_dbg(sh_chan->shdma_chan.dev, "Queue #%d to %d: %u@%x -> %x\n",
294 		sdesc->async_tx.cookie, sh_chan->shdma_chan.id,
295 		sh_desc->hw.tcr, sh_desc->hw.sar, sh_desc->hw.dar);
296 	/* Get the ld start address from ld_queue */
297 	dmae_set_reg(sh_chan, &sh_desc->hw);
298 	dmae_start(sh_chan);
299 }
300 
301 static bool sh_dmae_channel_busy(struct shdma_chan *schan)
302 {
303 	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
304 						    shdma_chan);
305 	return dmae_is_busy(sh_chan);
306 }
307 
308 static void sh_dmae_setup_xfer(struct shdma_chan *schan,
309 			       int slave_id)
310 {
311 	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
312 						    shdma_chan);
313 
314 	if (slave_id >= 0) {
315 		const struct sh_dmae_slave_config *cfg =
316 			sh_chan->config;
317 
318 		dmae_set_dmars(sh_chan, cfg->mid_rid);
319 		dmae_set_chcr(sh_chan, cfg->chcr);
320 	} else {
321 		dmae_init(sh_chan);
322 	}
323 }
324 
325 /*
326  * Find a slave channel configuration from the contoller list by either a slave
327  * ID in the non-DT case, or by a MID/RID value in the DT case
328  */
329 static const struct sh_dmae_slave_config *dmae_find_slave(
330 	struct sh_dmae_chan *sh_chan, int match)
331 {
332 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
333 	const struct sh_dmae_pdata *pdata = shdev->pdata;
334 	const struct sh_dmae_slave_config *cfg;
335 	int i;
336 
337 	if (!sh_chan->shdma_chan.dev->of_node) {
338 		if (match >= SH_DMA_SLAVE_NUMBER)
339 			return NULL;
340 
341 		for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
342 			if (cfg->slave_id == match)
343 				return cfg;
344 	} else {
345 		for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
346 			if (cfg->mid_rid == match) {
347 				sh_chan->shdma_chan.slave_id = i;
348 				return cfg;
349 			}
350 	}
351 
352 	return NULL;
353 }
354 
355 static int sh_dmae_set_slave(struct shdma_chan *schan,
356 			     int slave_id, dma_addr_t slave_addr, bool try)
357 {
358 	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
359 						    shdma_chan);
360 	const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, slave_id);
361 	if (!cfg)
362 		return -ENXIO;
363 
364 	if (!try) {
365 		sh_chan->config = cfg;
366 		sh_chan->slave_addr = slave_addr ? : cfg->addr;
367 	}
368 
369 	return 0;
370 }
371 
372 static void dmae_halt(struct sh_dmae_chan *sh_chan)
373 {
374 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
375 	u32 chcr = chcr_read(sh_chan);
376 
377 	chcr &= ~(CHCR_DE | CHCR_TE | shdev->chcr_ie_bit);
378 	chcr_write(sh_chan, chcr);
379 }
380 
381 static int sh_dmae_desc_setup(struct shdma_chan *schan,
382 			      struct shdma_desc *sdesc,
383 			      dma_addr_t src, dma_addr_t dst, size_t *len)
384 {
385 	struct sh_dmae_desc *sh_desc = container_of(sdesc,
386 					struct sh_dmae_desc, shdma_desc);
387 
388 	if (*len > schan->max_xfer_len)
389 		*len = schan->max_xfer_len;
390 
391 	sh_desc->hw.sar = src;
392 	sh_desc->hw.dar = dst;
393 	sh_desc->hw.tcr = *len;
394 
395 	return 0;
396 }
397 
398 static void sh_dmae_halt(struct shdma_chan *schan)
399 {
400 	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
401 						    shdma_chan);
402 	dmae_halt(sh_chan);
403 }
404 
405 static bool sh_dmae_chan_irq(struct shdma_chan *schan, int irq)
406 {
407 	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
408 						    shdma_chan);
409 
410 	if (!(chcr_read(sh_chan) & CHCR_TE))
411 		return false;
412 
413 	/* DMA stop */
414 	dmae_halt(sh_chan);
415 
416 	return true;
417 }
418 
419 static size_t sh_dmae_get_partial(struct shdma_chan *schan,
420 				  struct shdma_desc *sdesc)
421 {
422 	struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
423 						    shdma_chan);
424 	struct sh_dmae_desc *sh_desc = container_of(sdesc,
425 					struct sh_dmae_desc, shdma_desc);
426 	return sh_desc->hw.tcr -
427 		(sh_dmae_readl(sh_chan, TCR) << sh_chan->xmit_shift);
428 }
429 
430 /* Called from error IRQ or NMI */
431 static bool sh_dmae_reset(struct sh_dmae_device *shdev)
432 {
433 	bool ret;
434 
435 	/* halt the dma controller */
436 	sh_dmae_ctl_stop(shdev);
437 
438 	/* We cannot detect, which channel caused the error, have to reset all */
439 	ret = shdma_reset(&shdev->shdma_dev);
440 
441 	sh_dmae_rst(shdev);
442 
443 	return ret;
444 }
445 
446 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
447 static irqreturn_t sh_dmae_err(int irq, void *data)
448 {
449 	struct sh_dmae_device *shdev = data;
450 
451 	if (!(dmaor_read(shdev) & DMAOR_AE))
452 		return IRQ_NONE;
453 
454 	sh_dmae_reset(shdev);
455 	return IRQ_HANDLED;
456 }
457 #endif
458 
459 static bool sh_dmae_desc_completed(struct shdma_chan *schan,
460 				   struct shdma_desc *sdesc)
461 {
462 	struct sh_dmae_chan *sh_chan = container_of(schan,
463 					struct sh_dmae_chan, shdma_chan);
464 	struct sh_dmae_desc *sh_desc = container_of(sdesc,
465 					struct sh_dmae_desc, shdma_desc);
466 	u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
467 	u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
468 
469 	return	(sdesc->direction == DMA_DEV_TO_MEM &&
470 		 (sh_desc->hw.dar + sh_desc->hw.tcr) == dar_buf) ||
471 		(sdesc->direction != DMA_DEV_TO_MEM &&
472 		 (sh_desc->hw.sar + sh_desc->hw.tcr) == sar_buf);
473 }
474 
475 static bool sh_dmae_nmi_notify(struct sh_dmae_device *shdev)
476 {
477 	/* Fast path out if NMIF is not asserted for this controller */
478 	if ((dmaor_read(shdev) & DMAOR_NMIF) == 0)
479 		return false;
480 
481 	return sh_dmae_reset(shdev);
482 }
483 
484 static int sh_dmae_nmi_handler(struct notifier_block *self,
485 			       unsigned long cmd, void *data)
486 {
487 	struct sh_dmae_device *shdev;
488 	int ret = NOTIFY_DONE;
489 	bool triggered;
490 
491 	/*
492 	 * Only concern ourselves with NMI events.
493 	 *
494 	 * Normally we would check the die chain value, but as this needs
495 	 * to be architecture independent, check for NMI context instead.
496 	 */
497 	if (!in_nmi())
498 		return NOTIFY_DONE;
499 
500 	rcu_read_lock();
501 	list_for_each_entry_rcu(shdev, &sh_dmae_devices, node) {
502 		/*
503 		 * Only stop if one of the controllers has NMIF asserted,
504 		 * we do not want to interfere with regular address error
505 		 * handling or NMI events that don't concern the DMACs.
506 		 */
507 		triggered = sh_dmae_nmi_notify(shdev);
508 		if (triggered == true)
509 			ret = NOTIFY_OK;
510 	}
511 	rcu_read_unlock();
512 
513 	return ret;
514 }
515 
516 static struct notifier_block sh_dmae_nmi_notifier __read_mostly = {
517 	.notifier_call	= sh_dmae_nmi_handler,
518 
519 	/* Run before NMI debug handler and KGDB */
520 	.priority	= 1,
521 };
522 
523 static int sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
524 					int irq, unsigned long flags)
525 {
526 	const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
527 	struct shdma_dev *sdev = &shdev->shdma_dev;
528 	struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev);
529 	struct sh_dmae_chan *sh_chan;
530 	struct shdma_chan *schan;
531 	int err;
532 
533 	sh_chan = devm_kzalloc(sdev->dma_dev.dev, sizeof(struct sh_dmae_chan),
534 			       GFP_KERNEL);
535 	if (!sh_chan) {
536 		dev_err(sdev->dma_dev.dev,
537 			"No free memory for allocating dma channels!\n");
538 		return -ENOMEM;
539 	}
540 
541 	schan = &sh_chan->shdma_chan;
542 	schan->max_xfer_len = SH_DMA_TCR_MAX + 1;
543 
544 	shdma_chan_probe(sdev, schan, id);
545 
546 	sh_chan->base = shdev->chan_reg + chan_pdata->offset;
547 
548 	/* set up channel irq */
549 	if (pdev->id >= 0)
550 		snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
551 			 "sh-dmae%d.%d", pdev->id, id);
552 	else
553 		snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
554 			 "sh-dma%d", id);
555 
556 	err = shdma_request_irq(schan, irq, flags, sh_chan->dev_id);
557 	if (err) {
558 		dev_err(sdev->dma_dev.dev,
559 			"DMA channel %d request_irq error %d\n",
560 			id, err);
561 		goto err_no_irq;
562 	}
563 
564 	shdev->chan[id] = sh_chan;
565 	return 0;
566 
567 err_no_irq:
568 	/* remove from dmaengine device node */
569 	shdma_chan_remove(schan);
570 	return err;
571 }
572 
573 static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
574 {
575 	struct shdma_chan *schan;
576 	int i;
577 
578 	shdma_for_each_chan(schan, &shdev->shdma_dev, i) {
579 		BUG_ON(!schan);
580 
581 		shdma_chan_remove(schan);
582 	}
583 }
584 
585 #ifdef CONFIG_PM
586 static int sh_dmae_runtime_suspend(struct device *dev)
587 {
588 	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
589 
590 	sh_dmae_ctl_stop(shdev);
591 	return 0;
592 }
593 
594 static int sh_dmae_runtime_resume(struct device *dev)
595 {
596 	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
597 
598 	return sh_dmae_rst(shdev);
599 }
600 #endif
601 
602 #ifdef CONFIG_PM_SLEEP
603 static int sh_dmae_suspend(struct device *dev)
604 {
605 	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
606 
607 	sh_dmae_ctl_stop(shdev);
608 	return 0;
609 }
610 
611 static int sh_dmae_resume(struct device *dev)
612 {
613 	struct sh_dmae_device *shdev = dev_get_drvdata(dev);
614 	int i, ret;
615 
616 	ret = sh_dmae_rst(shdev);
617 	if (ret < 0)
618 		dev_err(dev, "Failed to reset!\n");
619 
620 	for (i = 0; i < shdev->pdata->channel_num; i++) {
621 		struct sh_dmae_chan *sh_chan = shdev->chan[i];
622 
623 		if (!sh_chan->shdma_chan.desc_num)
624 			continue;
625 
626 		if (sh_chan->shdma_chan.slave_id >= 0) {
627 			const struct sh_dmae_slave_config *cfg = sh_chan->config;
628 			dmae_set_dmars(sh_chan, cfg->mid_rid);
629 			dmae_set_chcr(sh_chan, cfg->chcr);
630 		} else {
631 			dmae_init(sh_chan);
632 		}
633 	}
634 
635 	return 0;
636 }
637 #endif
638 
639 static const struct dev_pm_ops sh_dmae_pm = {
640 	SET_SYSTEM_SLEEP_PM_OPS(sh_dmae_suspend, sh_dmae_resume)
641 	SET_RUNTIME_PM_OPS(sh_dmae_runtime_suspend, sh_dmae_runtime_resume,
642 			   NULL)
643 };
644 
645 static dma_addr_t sh_dmae_slave_addr(struct shdma_chan *schan)
646 {
647 	struct sh_dmae_chan *sh_chan = container_of(schan,
648 					struct sh_dmae_chan, shdma_chan);
649 
650 	/*
651 	 * Implicit BUG_ON(!sh_chan->config)
652 	 * This is an exclusive slave DMA operation, may only be called after a
653 	 * successful slave configuration.
654 	 */
655 	return sh_chan->slave_addr;
656 }
657 
658 static struct shdma_desc *sh_dmae_embedded_desc(void *buf, int i)
659 {
660 	return &((struct sh_dmae_desc *)buf)[i].shdma_desc;
661 }
662 
663 static const struct shdma_ops sh_dmae_shdma_ops = {
664 	.desc_completed = sh_dmae_desc_completed,
665 	.halt_channel = sh_dmae_halt,
666 	.channel_busy = sh_dmae_channel_busy,
667 	.slave_addr = sh_dmae_slave_addr,
668 	.desc_setup = sh_dmae_desc_setup,
669 	.set_slave = sh_dmae_set_slave,
670 	.setup_xfer = sh_dmae_setup_xfer,
671 	.start_xfer = sh_dmae_start_xfer,
672 	.embedded_desc = sh_dmae_embedded_desc,
673 	.chan_irq = sh_dmae_chan_irq,
674 	.get_partial = sh_dmae_get_partial,
675 };
676 
677 static const struct of_device_id sh_dmae_of_match[] = {
678 	{.compatible = "renesas,shdma-r8a73a4", .data = r8a73a4_shdma_devid,},
679 	{}
680 };
681 MODULE_DEVICE_TABLE(of, sh_dmae_of_match);
682 
683 static int sh_dmae_probe(struct platform_device *pdev)
684 {
685 	const enum dma_slave_buswidth widths =
686 		DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
687 		DMA_SLAVE_BUSWIDTH_4_BYTES  | DMA_SLAVE_BUSWIDTH_8_BYTES |
688 		DMA_SLAVE_BUSWIDTH_16_BYTES | DMA_SLAVE_BUSWIDTH_32_BYTES;
689 	const struct sh_dmae_pdata *pdata;
690 	unsigned long chan_flag[SH_DMAE_MAX_CHANNELS] = {};
691 	int chan_irq[SH_DMAE_MAX_CHANNELS];
692 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
693 	unsigned long irqflags = 0;
694 	int errirq;
695 #endif
696 	int err, i, irq_cnt = 0, irqres = 0, irq_cap = 0;
697 	struct sh_dmae_device *shdev;
698 	struct dma_device *dma_dev;
699 	struct resource *chan, *dmars, *errirq_res, *chanirq_res;
700 
701 	if (pdev->dev.of_node)
702 		pdata = of_match_device(sh_dmae_of_match, &pdev->dev)->data;
703 	else
704 		pdata = dev_get_platdata(&pdev->dev);
705 
706 	/* get platform data */
707 	if (!pdata || !pdata->channel_num)
708 		return -ENODEV;
709 
710 	chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
711 	/* DMARS area is optional */
712 	dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
713 	/*
714 	 * IRQ resources:
715 	 * 1. there always must be at least one IRQ IO-resource. On SH4 it is
716 	 *    the error IRQ, in which case it is the only IRQ in this resource:
717 	 *    start == end. If it is the only IRQ resource, all channels also
718 	 *    use the same IRQ.
719 	 * 2. DMA channel IRQ resources can be specified one per resource or in
720 	 *    ranges (start != end)
721 	 * 3. iff all events (channels and, optionally, error) on this
722 	 *    controller use the same IRQ, only one IRQ resource can be
723 	 *    specified, otherwise there must be one IRQ per channel, even if
724 	 *    some of them are equal
725 	 * 4. if all IRQs on this controller are equal or if some specific IRQs
726 	 *    specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
727 	 *    requested with the IRQF_SHARED flag
728 	 */
729 	errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
730 	if (!chan || !errirq_res)
731 		return -ENODEV;
732 
733 	shdev = devm_kzalloc(&pdev->dev, sizeof(struct sh_dmae_device),
734 			     GFP_KERNEL);
735 	if (!shdev) {
736 		dev_err(&pdev->dev, "Not enough memory\n");
737 		return -ENOMEM;
738 	}
739 
740 	dma_dev = &shdev->shdma_dev.dma_dev;
741 
742 	shdev->chan_reg = devm_ioremap_resource(&pdev->dev, chan);
743 	if (IS_ERR(shdev->chan_reg))
744 		return PTR_ERR(shdev->chan_reg);
745 	if (dmars) {
746 		shdev->dmars = devm_ioremap_resource(&pdev->dev, dmars);
747 		if (IS_ERR(shdev->dmars))
748 			return PTR_ERR(shdev->dmars);
749 	}
750 
751 	dma_dev->src_addr_widths = widths;
752 	dma_dev->dst_addr_widths = widths;
753 	dma_dev->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
754 	dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
755 
756 	if (!pdata->slave_only)
757 		dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
758 	if (pdata->slave && pdata->slave_num)
759 		dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
760 
761 	/* Default transfer size of 32 bytes requires 32-byte alignment */
762 	dma_dev->copy_align = LOG2_DEFAULT_XFER_SIZE;
763 
764 	shdev->shdma_dev.ops = &sh_dmae_shdma_ops;
765 	shdev->shdma_dev.desc_size = sizeof(struct sh_dmae_desc);
766 	err = shdma_init(&pdev->dev, &shdev->shdma_dev,
767 			      pdata->channel_num);
768 	if (err < 0)
769 		goto eshdma;
770 
771 	/* platform data */
772 	shdev->pdata = pdata;
773 
774 	if (pdata->chcr_offset)
775 		shdev->chcr_offset = pdata->chcr_offset;
776 	else
777 		shdev->chcr_offset = CHCR;
778 
779 	if (pdata->chcr_ie_bit)
780 		shdev->chcr_ie_bit = pdata->chcr_ie_bit;
781 	else
782 		shdev->chcr_ie_bit = CHCR_IE;
783 
784 	platform_set_drvdata(pdev, shdev);
785 
786 	pm_runtime_enable(&pdev->dev);
787 	err = pm_runtime_get_sync(&pdev->dev);
788 	if (err < 0)
789 		dev_err(&pdev->dev, "%s(): GET = %d\n", __func__, err);
790 
791 	spin_lock_irq(&sh_dmae_lock);
792 	list_add_tail_rcu(&shdev->node, &sh_dmae_devices);
793 	spin_unlock_irq(&sh_dmae_lock);
794 
795 	/* reset dma controller - only needed as a test */
796 	err = sh_dmae_rst(shdev);
797 	if (err)
798 		goto rst_err;
799 
800 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
801 	chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
802 
803 	if (!chanirq_res)
804 		chanirq_res = errirq_res;
805 	else
806 		irqres++;
807 
808 	if (chanirq_res == errirq_res ||
809 	    (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
810 		irqflags = IRQF_SHARED;
811 
812 	errirq = errirq_res->start;
813 
814 	err = devm_request_irq(&pdev->dev, errirq, sh_dmae_err, irqflags,
815 			       "DMAC Address Error", shdev);
816 	if (err) {
817 		dev_err(&pdev->dev,
818 			"DMA failed requesting irq #%d, error %d\n",
819 			errirq, err);
820 		goto eirq_err;
821 	}
822 
823 #else
824 	chanirq_res = errirq_res;
825 #endif /* CONFIG_CPU_SH4 || CONFIG_ARCH_SHMOBILE */
826 
827 	if (chanirq_res->start == chanirq_res->end &&
828 	    !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
829 		/* Special case - all multiplexed */
830 		for (; irq_cnt < pdata->channel_num; irq_cnt++) {
831 			if (irq_cnt < SH_DMAE_MAX_CHANNELS) {
832 				chan_irq[irq_cnt] = chanirq_res->start;
833 				chan_flag[irq_cnt] = IRQF_SHARED;
834 			} else {
835 				irq_cap = 1;
836 				break;
837 			}
838 		}
839 	} else {
840 		do {
841 			for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
842 				if (irq_cnt >= SH_DMAE_MAX_CHANNELS) {
843 					irq_cap = 1;
844 					break;
845 				}
846 
847 				if ((errirq_res->flags & IORESOURCE_BITS) ==
848 				    IORESOURCE_IRQ_SHAREABLE)
849 					chan_flag[irq_cnt] = IRQF_SHARED;
850 				else
851 					chan_flag[irq_cnt] = 0;
852 				dev_dbg(&pdev->dev,
853 					"Found IRQ %d for channel %d\n",
854 					i, irq_cnt);
855 				chan_irq[irq_cnt++] = i;
856 			}
857 
858 			if (irq_cnt >= SH_DMAE_MAX_CHANNELS)
859 				break;
860 
861 			chanirq_res = platform_get_resource(pdev,
862 						IORESOURCE_IRQ, ++irqres);
863 		} while (irq_cnt < pdata->channel_num && chanirq_res);
864 	}
865 
866 	/* Create DMA Channel */
867 	for (i = 0; i < irq_cnt; i++) {
868 		err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
869 		if (err)
870 			goto chan_probe_err;
871 	}
872 
873 	if (irq_cap)
874 		dev_notice(&pdev->dev, "Attempting to register %d DMA "
875 			   "channels when a maximum of %d are supported.\n",
876 			   pdata->channel_num, SH_DMAE_MAX_CHANNELS);
877 
878 	pm_runtime_put(&pdev->dev);
879 
880 	err = dma_async_device_register(&shdev->shdma_dev.dma_dev);
881 	if (err < 0)
882 		goto edmadevreg;
883 
884 	return err;
885 
886 edmadevreg:
887 	pm_runtime_get(&pdev->dev);
888 
889 chan_probe_err:
890 	sh_dmae_chan_remove(shdev);
891 
892 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
893 eirq_err:
894 #endif
895 rst_err:
896 	spin_lock_irq(&sh_dmae_lock);
897 	list_del_rcu(&shdev->node);
898 	spin_unlock_irq(&sh_dmae_lock);
899 
900 	pm_runtime_put(&pdev->dev);
901 	pm_runtime_disable(&pdev->dev);
902 
903 	shdma_cleanup(&shdev->shdma_dev);
904 eshdma:
905 	synchronize_rcu();
906 
907 	return err;
908 }
909 
910 static int sh_dmae_remove(struct platform_device *pdev)
911 {
912 	struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
913 	struct dma_device *dma_dev = &shdev->shdma_dev.dma_dev;
914 
915 	dma_async_device_unregister(dma_dev);
916 
917 	spin_lock_irq(&sh_dmae_lock);
918 	list_del_rcu(&shdev->node);
919 	spin_unlock_irq(&sh_dmae_lock);
920 
921 	pm_runtime_disable(&pdev->dev);
922 
923 	sh_dmae_chan_remove(shdev);
924 	shdma_cleanup(&shdev->shdma_dev);
925 
926 	synchronize_rcu();
927 
928 	return 0;
929 }
930 
931 static struct platform_driver sh_dmae_driver = {
932 	.driver		= {
933 		.pm	= &sh_dmae_pm,
934 		.name	= SH_DMAE_DRV_NAME,
935 		.of_match_table = sh_dmae_of_match,
936 	},
937 	.remove		= sh_dmae_remove,
938 };
939 
940 static int __init sh_dmae_init(void)
941 {
942 	/* Wire up NMI handling */
943 	int err = register_die_notifier(&sh_dmae_nmi_notifier);
944 	if (err)
945 		return err;
946 
947 	return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
948 }
949 module_init(sh_dmae_init);
950 
951 static void __exit sh_dmae_exit(void)
952 {
953 	platform_driver_unregister(&sh_dmae_driver);
954 
955 	unregister_die_notifier(&sh_dmae_nmi_notifier);
956 }
957 module_exit(sh_dmae_exit);
958 
959 MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
960 MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
961 MODULE_LICENSE("GPL");
962 MODULE_ALIAS("platform:" SH_DMAE_DRV_NAME);
963