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  1/*
  2 * DMA controller driver for CSR SiRFprimaII
  3 *
  4 * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
  5 *
  6 * Licensed under GPLv2 or later.
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/dmaengine.h>
 11#include <linux/dma-mapping.h>
 12#include <linux/pm_runtime.h>
 13#include <linux/interrupt.h>
 14#include <linux/io.h>
 15#include <linux/slab.h>
 16#include <linux/of_irq.h>
 17#include <linux/of_address.h>
 18#include <linux/of_device.h>
 19#include <linux/of_platform.h>
 20#include <linux/clk.h>
 21#include <linux/of_dma.h>
 22#include <linux/sirfsoc_dma.h>
 23
 24#include "dmaengine.h"
 25
 26#define SIRFSOC_DMA_DESCRIPTORS                 16
 27#define SIRFSOC_DMA_CHANNELS                    16
 28
 29#define SIRFSOC_DMA_CH_ADDR                     0x00
 30#define SIRFSOC_DMA_CH_XLEN                     0x04
 31#define SIRFSOC_DMA_CH_YLEN                     0x08
 32#define SIRFSOC_DMA_CH_CTRL                     0x0C
 33
 34#define SIRFSOC_DMA_WIDTH_0                     0x100
 35#define SIRFSOC_DMA_CH_VALID                    0x140
 36#define SIRFSOC_DMA_CH_INT                      0x144
 37#define SIRFSOC_DMA_INT_EN                      0x148
 38#define SIRFSOC_DMA_INT_EN_CLR			0x14C
 39#define SIRFSOC_DMA_CH_LOOP_CTRL                0x150
 40#define SIRFSOC_DMA_CH_LOOP_CTRL_CLR            0x15C
 41
 42#define SIRFSOC_DMA_MODE_CTRL_BIT               4
 43#define SIRFSOC_DMA_DIR_CTRL_BIT                5
 44
 45/* xlen and dma_width register is in 4 bytes boundary */
 46#define SIRFSOC_DMA_WORD_LEN			4
 47
 48struct sirfsoc_dma_desc {
 49	struct dma_async_tx_descriptor	desc;
 50	struct list_head		node;
 51
 52	/* SiRFprimaII 2D-DMA parameters */
 53
 54	int             xlen;           /* DMA xlen */
 55	int             ylen;           /* DMA ylen */
 56	int             width;          /* DMA width */
 57	int             dir;
 58	bool            cyclic;         /* is loop DMA? */
 59	u32             addr;		/* DMA buffer address */
 60};
 61
 62struct sirfsoc_dma_chan {
 63	struct dma_chan			chan;
 64	struct list_head		free;
 65	struct list_head		prepared;
 66	struct list_head		queued;
 67	struct list_head		active;
 68	struct list_head		completed;
 69	unsigned long			happened_cyclic;
 70	unsigned long			completed_cyclic;
 71
 72	/* Lock for this structure */
 73	spinlock_t			lock;
 74
 75	int				mode;
 76};
 77
 78struct sirfsoc_dma_regs {
 79	u32				ctrl[SIRFSOC_DMA_CHANNELS];
 80	u32				interrupt_en;
 81};
 82
 83struct sirfsoc_dma {
 84	struct dma_device		dma;
 85	struct tasklet_struct		tasklet;
 86	struct sirfsoc_dma_chan		channels[SIRFSOC_DMA_CHANNELS];
 87	void __iomem			*base;
 88	int				irq;
 89	struct clk			*clk;
 90	bool				is_marco;
 91	struct sirfsoc_dma_regs		regs_save;
 92};
 93
 94#define DRV_NAME	"sirfsoc_dma"
 95
 96static int sirfsoc_dma_runtime_suspend(struct device *dev);
 97
 98/* Convert struct dma_chan to struct sirfsoc_dma_chan */
 99static inline
100struct sirfsoc_dma_chan *dma_chan_to_sirfsoc_dma_chan(struct dma_chan *c)
101{
102	return container_of(c, struct sirfsoc_dma_chan, chan);
103}
104
105/* Convert struct dma_chan to struct sirfsoc_dma */
106static inline struct sirfsoc_dma *dma_chan_to_sirfsoc_dma(struct dma_chan *c)
107{
108	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(c);
109	return container_of(schan, struct sirfsoc_dma, channels[c->chan_id]);
110}
111
112/* Execute all queued DMA descriptors */
113static void sirfsoc_dma_execute(struct sirfsoc_dma_chan *schan)
114{
115	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
116	int cid = schan->chan.chan_id;
117	struct sirfsoc_dma_desc *sdesc = NULL;
118
119	/*
120	 * lock has been held by functions calling this, so we don't hold
121	 * lock again
122	 */
123
124	sdesc = list_first_entry(&schan->queued, struct sirfsoc_dma_desc,
125		node);
126	/* Move the first queued descriptor to active list */
127	list_move_tail(&sdesc->node, &schan->active);
128
129	/* Start the DMA transfer */
130	writel_relaxed(sdesc->width, sdma->base + SIRFSOC_DMA_WIDTH_0 +
131		cid * 4);
132	writel_relaxed(cid | (schan->mode << SIRFSOC_DMA_MODE_CTRL_BIT) |
133		(sdesc->dir << SIRFSOC_DMA_DIR_CTRL_BIT),
134		sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_CTRL);
135	writel_relaxed(sdesc->xlen, sdma->base + cid * 0x10 +
136		SIRFSOC_DMA_CH_XLEN);
137	writel_relaxed(sdesc->ylen, sdma->base + cid * 0x10 +
138		SIRFSOC_DMA_CH_YLEN);
139	writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN) |
140		(1 << cid), sdma->base + SIRFSOC_DMA_INT_EN);
141
142	/*
143	 * writel has an implict memory write barrier to make sure data is
144	 * flushed into memory before starting DMA
145	 */
146	writel(sdesc->addr >> 2, sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_ADDR);
147
148	if (sdesc->cyclic) {
149		writel((1 << cid) | 1 << (cid + 16) |
150			readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL),
151			sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
152		schan->happened_cyclic = schan->completed_cyclic = 0;
153	}
154}
155
156/* Interrupt handler */
157static irqreturn_t sirfsoc_dma_irq(int irq, void *data)
158{
159	struct sirfsoc_dma *sdma = data;
160	struct sirfsoc_dma_chan *schan;
161	struct sirfsoc_dma_desc *sdesc = NULL;
162	u32 is;
163	int ch;
164
165	is = readl(sdma->base + SIRFSOC_DMA_CH_INT);
166	while ((ch = fls(is) - 1) >= 0) {
167		is &= ~(1 << ch);
168		writel_relaxed(1 << ch, sdma->base + SIRFSOC_DMA_CH_INT);
169		schan = &sdma->channels[ch];
170
171		spin_lock(&schan->lock);
172
173		sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc,
174			node);
175		if (!sdesc->cyclic) {
176			/* Execute queued descriptors */
177			list_splice_tail_init(&schan->active, &schan->completed);
178			if (!list_empty(&schan->queued))
179				sirfsoc_dma_execute(schan);
180		} else
181			schan->happened_cyclic++;
182
183		spin_unlock(&schan->lock);
184	}
185
186	/* Schedule tasklet */
187	tasklet_schedule(&sdma->tasklet);
188
189	return IRQ_HANDLED;
190}
191
192/* process completed descriptors */
193static void sirfsoc_dma_process_completed(struct sirfsoc_dma *sdma)
194{
195	dma_cookie_t last_cookie = 0;
196	struct sirfsoc_dma_chan *schan;
197	struct sirfsoc_dma_desc *sdesc;
198	struct dma_async_tx_descriptor *desc;
199	unsigned long flags;
200	unsigned long happened_cyclic;
201	LIST_HEAD(list);
202	int i;
203
204	for (i = 0; i < sdma->dma.chancnt; i++) {
205		schan = &sdma->channels[i];
206
207		/* Get all completed descriptors */
208		spin_lock_irqsave(&schan->lock, flags);
209		if (!list_empty(&schan->completed)) {
210			list_splice_tail_init(&schan->completed, &list);
211			spin_unlock_irqrestore(&schan->lock, flags);
212
213			/* Execute callbacks and run dependencies */
214			list_for_each_entry(sdesc, &list, node) {
215				desc = &sdesc->desc;
216
217				if (desc->callback)
218					desc->callback(desc->callback_param);
219
220				last_cookie = desc->cookie;
221				dma_run_dependencies(desc);
222			}
223
224			/* Free descriptors */
225			spin_lock_irqsave(&schan->lock, flags);
226			list_splice_tail_init(&list, &schan->free);
227			schan->chan.completed_cookie = last_cookie;
228			spin_unlock_irqrestore(&schan->lock, flags);
229		} else {
230			/* for cyclic channel, desc is always in active list */
231			sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc,
232				node);
233
234			if (!sdesc || (sdesc && !sdesc->cyclic)) {
235				/* without active cyclic DMA */
236				spin_unlock_irqrestore(&schan->lock, flags);
237				continue;
238			}
239
240			/* cyclic DMA */
241			happened_cyclic = schan->happened_cyclic;
242			spin_unlock_irqrestore(&schan->lock, flags);
243
244			desc = &sdesc->desc;
245			while (happened_cyclic != schan->completed_cyclic) {
246				if (desc->callback)
247					desc->callback(desc->callback_param);
248				schan->completed_cyclic++;
249			}
250		}
251	}
252}
253
254/* DMA Tasklet */
255static void sirfsoc_dma_tasklet(unsigned long data)
256{
257	struct sirfsoc_dma *sdma = (void *)data;
258
259	sirfsoc_dma_process_completed(sdma);
260}
261
262/* Submit descriptor to hardware */
263static dma_cookie_t sirfsoc_dma_tx_submit(struct dma_async_tx_descriptor *txd)
264{
265	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(txd->chan);
266	struct sirfsoc_dma_desc *sdesc;
267	unsigned long flags;
268	dma_cookie_t cookie;
269
270	sdesc = container_of(txd, struct sirfsoc_dma_desc, desc);
271
272	spin_lock_irqsave(&schan->lock, flags);
273
274	/* Move descriptor to queue */
275	list_move_tail(&sdesc->node, &schan->queued);
276
277	cookie = dma_cookie_assign(txd);
278
279	spin_unlock_irqrestore(&schan->lock, flags);
280
281	return cookie;
282}
283
284static int sirfsoc_dma_slave_config(struct sirfsoc_dma_chan *schan,
285	struct dma_slave_config *config)
286{
287	unsigned long flags;
288
289	if ((config->src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) ||
290		(config->dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES))
291		return -EINVAL;
292
293	spin_lock_irqsave(&schan->lock, flags);
294	schan->mode = (config->src_maxburst == 4 ? 1 : 0);
295	spin_unlock_irqrestore(&schan->lock, flags);
296
297	return 0;
298}
299
300static int sirfsoc_dma_terminate_all(struct sirfsoc_dma_chan *schan)
301{
302	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
303	int cid = schan->chan.chan_id;
304	unsigned long flags;
305
306	spin_lock_irqsave(&schan->lock, flags);
307
308	if (!sdma->is_marco) {
309		writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN) &
310			~(1 << cid), sdma->base + SIRFSOC_DMA_INT_EN);
311		writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL)
312			& ~((1 << cid) | 1 << (cid + 16)),
313			sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
314	} else {
315		writel_relaxed(1 << cid, sdma->base + SIRFSOC_DMA_INT_EN_CLR);
316		writel_relaxed((1 << cid) | 1 << (cid + 16),
317			sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL_CLR);
318	}
319
320	writel_relaxed(1 << cid, sdma->base + SIRFSOC_DMA_CH_VALID);
321
322	list_splice_tail_init(&schan->active, &schan->free);
323	list_splice_tail_init(&schan->queued, &schan->free);
324
325	spin_unlock_irqrestore(&schan->lock, flags);
326
327	return 0;
328}
329
330static int sirfsoc_dma_pause_chan(struct sirfsoc_dma_chan *schan)
331{
332	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
333	int cid = schan->chan.chan_id;
334	unsigned long flags;
335
336	spin_lock_irqsave(&schan->lock, flags);
337
338	if (!sdma->is_marco)
339		writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL)
340			& ~((1 << cid) | 1 << (cid + 16)),
341			sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
342	else
343		writel_relaxed((1 << cid) | 1 << (cid + 16),
344			sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL_CLR);
345
346	spin_unlock_irqrestore(&schan->lock, flags);
347
348	return 0;
349}
350
351static int sirfsoc_dma_resume_chan(struct sirfsoc_dma_chan *schan)
352{
353	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
354	int cid = schan->chan.chan_id;
355	unsigned long flags;
356
357	spin_lock_irqsave(&schan->lock, flags);
358
359	if (!sdma->is_marco)
360		writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL)
361			| ((1 << cid) | 1 << (cid + 16)),
362			sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
363	else
364		writel_relaxed((1 << cid) | 1 << (cid + 16),
365			sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
366
367	spin_unlock_irqrestore(&schan->lock, flags);
368
369	return 0;
370}
371
372static int sirfsoc_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
373	unsigned long arg)
374{
375	struct dma_slave_config *config;
376	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
377
378	switch (cmd) {
379	case DMA_PAUSE:
380		return sirfsoc_dma_pause_chan(schan);
381	case DMA_RESUME:
382		return sirfsoc_dma_resume_chan(schan);
383	case DMA_TERMINATE_ALL:
384		return sirfsoc_dma_terminate_all(schan);
385	case DMA_SLAVE_CONFIG:
386		config = (struct dma_slave_config *)arg;
387		return sirfsoc_dma_slave_config(schan, config);
388
389	default:
390		break;
391	}
392
393	return -ENOSYS;
394}
395
396/* Alloc channel resources */
397static int sirfsoc_dma_alloc_chan_resources(struct dma_chan *chan)
398{
399	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
400	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
401	struct sirfsoc_dma_desc *sdesc;
402	unsigned long flags;
403	LIST_HEAD(descs);
404	int i;
405
406	pm_runtime_get_sync(sdma->dma.dev);
407
408	/* Alloc descriptors for this channel */
409	for (i = 0; i < SIRFSOC_DMA_DESCRIPTORS; i++) {
410		sdesc = kzalloc(sizeof(*sdesc), GFP_KERNEL);
411		if (!sdesc) {
412			dev_notice(sdma->dma.dev, "Memory allocation error. "
413				"Allocated only %u descriptors\n", i);
414			break;
415		}
416
417		dma_async_tx_descriptor_init(&sdesc->desc, chan);
418		sdesc->desc.flags = DMA_CTRL_ACK;
419		sdesc->desc.tx_submit = sirfsoc_dma_tx_submit;
420
421		list_add_tail(&sdesc->node, &descs);
422	}
423
424	/* Return error only if no descriptors were allocated */
425	if (i == 0)
426		return -ENOMEM;
427
428	spin_lock_irqsave(&schan->lock, flags);
429
430	list_splice_tail_init(&descs, &schan->free);
431	spin_unlock_irqrestore(&schan->lock, flags);
432
433	return i;
434}
435
436/* Free channel resources */
437static void sirfsoc_dma_free_chan_resources(struct dma_chan *chan)
438{
439	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
440	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
441	struct sirfsoc_dma_desc *sdesc, *tmp;
442	unsigned long flags;
443	LIST_HEAD(descs);
444
445	spin_lock_irqsave(&schan->lock, flags);
446
447	/* Channel must be idle */
448	BUG_ON(!list_empty(&schan->prepared));
449	BUG_ON(!list_empty(&schan->queued));
450	BUG_ON(!list_empty(&schan->active));
451	BUG_ON(!list_empty(&schan->completed));
452
453	/* Move data */
454	list_splice_tail_init(&schan->free, &descs);
455
456	spin_unlock_irqrestore(&schan->lock, flags);
457
458	/* Free descriptors */
459	list_for_each_entry_safe(sdesc, tmp, &descs, node)
460		kfree(sdesc);
461
462	pm_runtime_put(sdma->dma.dev);
463}
464
465/* Send pending descriptor to hardware */
466static void sirfsoc_dma_issue_pending(struct dma_chan *chan)
467{
468	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
469	unsigned long flags;
470
471	spin_lock_irqsave(&schan->lock, flags);
472
473	if (list_empty(&schan->active) && !list_empty(&schan->queued))
474		sirfsoc_dma_execute(schan);
475
476	spin_unlock_irqrestore(&schan->lock, flags);
477}
478
479/* Check request completion status */
480static enum dma_status
481sirfsoc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
482	struct dma_tx_state *txstate)
483{
484	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
485	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
486	unsigned long flags;
487	enum dma_status ret;
488	struct sirfsoc_dma_desc *sdesc;
489	int cid = schan->chan.chan_id;
490	unsigned long dma_pos;
491	unsigned long dma_request_bytes;
492	unsigned long residue;
493
494	spin_lock_irqsave(&schan->lock, flags);
495
496	sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc,
497			node);
498	dma_request_bytes = (sdesc->xlen + 1) * (sdesc->ylen + 1) *
499		(sdesc->width * SIRFSOC_DMA_WORD_LEN);
500
501	ret = dma_cookie_status(chan, cookie, txstate);
502	dma_pos = readl_relaxed(sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_ADDR)
503		<< 2;
504	residue = dma_request_bytes - (dma_pos - sdesc->addr);
505	dma_set_residue(txstate, residue);
506
507	spin_unlock_irqrestore(&schan->lock, flags);
508
509	return ret;
510}
511
512static struct dma_async_tx_descriptor *sirfsoc_dma_prep_interleaved(
513	struct dma_chan *chan, struct dma_interleaved_template *xt,
514	unsigned long flags)
515{
516	struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
517	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
518	struct sirfsoc_dma_desc *sdesc = NULL;
519	unsigned long iflags;
520	int ret;
521
522	if ((xt->dir != DMA_MEM_TO_DEV) && (xt->dir != DMA_DEV_TO_MEM)) {
523		ret = -EINVAL;
524		goto err_dir;
525	}
526
527	/* Get free descriptor */
528	spin_lock_irqsave(&schan->lock, iflags);
529	if (!list_empty(&schan->free)) {
530		sdesc = list_first_entry(&schan->free, struct sirfsoc_dma_desc,
531			node);
532		list_del(&sdesc->node);
533	}
534	spin_unlock_irqrestore(&schan->lock, iflags);
535
536	if (!sdesc) {
537		/* try to free completed descriptors */
538		sirfsoc_dma_process_completed(sdma);
539		ret = 0;
540		goto no_desc;
541	}
542
543	/* Place descriptor in prepared list */
544	spin_lock_irqsave(&schan->lock, iflags);
545
546	/*
547	 * Number of chunks in a frame can only be 1 for prima2
548	 * and ylen (number of frame - 1) must be at least 0
549	 */
550	if ((xt->frame_size == 1) && (xt->numf > 0)) {
551		sdesc->cyclic = 0;
552		sdesc->xlen = xt->sgl[0].size / SIRFSOC_DMA_WORD_LEN;
553		sdesc->width = (xt->sgl[0].size + xt->sgl[0].icg) /
554				SIRFSOC_DMA_WORD_LEN;
555		sdesc->ylen = xt->numf - 1;
556		if (xt->dir == DMA_MEM_TO_DEV) {
557			sdesc->addr = xt->src_start;
558			sdesc->dir = 1;
559		} else {
560			sdesc->addr = xt->dst_start;
561			sdesc->dir = 0;
562		}
563
564		list_add_tail(&sdesc->node, &schan->prepared);
565	} else {
566		pr_err("sirfsoc DMA Invalid xfer\n");
567		ret = -EINVAL;
568		goto err_xfer;
569	}
570	spin_unlock_irqrestore(&schan->lock, iflags);
571
572	return &sdesc->desc;
573err_xfer:
574	spin_unlock_irqrestore(&schan->lock, iflags);
575no_desc:
576err_dir:
577	return ERR_PTR(ret);
578}
579
580static struct dma_async_tx_descriptor *
581sirfsoc_dma_prep_cyclic(struct dma_chan *chan, dma_addr_t addr,
582	size_t buf_len, size_t period_len,
583	enum dma_transfer_direction direction, unsigned long flags, void *context)
584{
585	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
586	struct sirfsoc_dma_desc *sdesc = NULL;
587	unsigned long iflags;
588
589	/*
590	 * we only support cycle transfer with 2 period
591	 * If the X-length is set to 0, it would be the loop mode.
592	 * The DMA address keeps increasing until reaching the end of a loop
593	 * area whose size is defined by (DMA_WIDTH x (Y_LENGTH + 1)). Then
594	 * the DMA address goes back to the beginning of this area.
595	 * In loop mode, the DMA data region is divided into two parts, BUFA
596	 * and BUFB. DMA controller generates interrupts twice in each loop:
597	 * when the DMA address reaches the end of BUFA or the end of the
598	 * BUFB
599	 */
600	if (buf_len !=  2 * period_len)
601		return ERR_PTR(-EINVAL);
602
603	/* Get free descriptor */
604	spin_lock_irqsave(&schan->lock, iflags);
605	if (!list_empty(&schan->free)) {
606		sdesc = list_first_entry(&schan->free, struct sirfsoc_dma_desc,
607			node);
608		list_del(&sdesc->node);
609	}
610	spin_unlock_irqrestore(&schan->lock, iflags);
611
612	if (!sdesc)
613		return NULL;
614
615	/* Place descriptor in prepared list */
616	spin_lock_irqsave(&schan->lock, iflags);
617	sdesc->addr = addr;
618	sdesc->cyclic = 1;
619	sdesc->xlen = 0;
620	sdesc->ylen = buf_len / SIRFSOC_DMA_WORD_LEN - 1;
621	sdesc->width = 1;
622	list_add_tail(&sdesc->node, &schan->prepared);
623	spin_unlock_irqrestore(&schan->lock, iflags);
624
625	return &sdesc->desc;
626}
627
628/*
629 * The DMA controller consists of 16 independent DMA channels.
630 * Each channel is allocated to a different function
631 */
632bool sirfsoc_dma_filter_id(struct dma_chan *chan, void *chan_id)
633{
634	unsigned int ch_nr = (unsigned int) chan_id;
635
636	if (ch_nr == chan->chan_id +
637		chan->device->dev_id * SIRFSOC_DMA_CHANNELS)
638		return true;
639
640	return false;
641}
642EXPORT_SYMBOL(sirfsoc_dma_filter_id);
643
644#define SIRFSOC_DMA_BUSWIDTHS \
645	(BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
646	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
647	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
648	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
649	BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
650
651static int sirfsoc_dma_device_slave_caps(struct dma_chan *dchan,
652	struct dma_slave_caps *caps)
653{
654	caps->src_addr_widths = SIRFSOC_DMA_BUSWIDTHS;
655	caps->dstn_addr_widths = SIRFSOC_DMA_BUSWIDTHS;
656	caps->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
657	caps->cmd_pause = true;
658	caps->cmd_terminate = true;
659
660	return 0;
661}
662
663static struct dma_chan *of_dma_sirfsoc_xlate(struct of_phandle_args *dma_spec,
664	struct of_dma *ofdma)
665{
666	struct sirfsoc_dma *sdma = ofdma->of_dma_data;
667	unsigned int request = dma_spec->args[0];
668
669	if (request >= SIRFSOC_DMA_CHANNELS)
670		return NULL;
671
672	return dma_get_slave_channel(&sdma->channels[request].chan);
673}
674
675static int sirfsoc_dma_probe(struct platform_device *op)
676{
677	struct device_node *dn = op->dev.of_node;
678	struct device *dev = &op->dev;
679	struct dma_device *dma;
680	struct sirfsoc_dma *sdma;
681	struct sirfsoc_dma_chan *schan;
682	struct resource res;
683	ulong regs_start, regs_size;
684	u32 id;
685	int ret, i;
686
687	sdma = devm_kzalloc(dev, sizeof(*sdma), GFP_KERNEL);
688	if (!sdma) {
689		dev_err(dev, "Memory exhausted!\n");
690		return -ENOMEM;
691	}
692
693	if (of_device_is_compatible(dn, "sirf,marco-dmac"))
694		sdma->is_marco = true;
695
696	if (of_property_read_u32(dn, "cell-index", &id)) {
697		dev_err(dev, "Fail to get DMAC index\n");
698		return -ENODEV;
699	}
700
701	sdma->irq = irq_of_parse_and_map(dn, 0);
702	if (sdma->irq == NO_IRQ) {
703		dev_err(dev, "Error mapping IRQ!\n");
704		return -EINVAL;
705	}
706
707	sdma->clk = devm_clk_get(dev, NULL);
708	if (IS_ERR(sdma->clk)) {
709		dev_err(dev, "failed to get a clock.\n");
710		return PTR_ERR(sdma->clk);
711	}
712
713	ret = of_address_to_resource(dn, 0, &res);
714	if (ret) {
715		dev_err(dev, "Error parsing memory region!\n");
716		goto irq_dispose;
717	}
718
719	regs_start = res.start;
720	regs_size = resource_size(&res);
721
722	sdma->base = devm_ioremap(dev, regs_start, regs_size);
723	if (!sdma->base) {
724		dev_err(dev, "Error mapping memory region!\n");
725		ret = -ENOMEM;
726		goto irq_dispose;
727	}
728
729	ret = request_irq(sdma->irq, &sirfsoc_dma_irq, 0, DRV_NAME, sdma);
730	if (ret) {
731		dev_err(dev, "Error requesting IRQ!\n");
732		ret = -EINVAL;
733		goto irq_dispose;
734	}
735
736	dma = &sdma->dma;
737	dma->dev = dev;
738	dma->chancnt = SIRFSOC_DMA_CHANNELS;
739
740	dma->device_alloc_chan_resources = sirfsoc_dma_alloc_chan_resources;
741	dma->device_free_chan_resources = sirfsoc_dma_free_chan_resources;
742	dma->device_issue_pending = sirfsoc_dma_issue_pending;
743	dma->device_control = sirfsoc_dma_control;
744	dma->device_tx_status = sirfsoc_dma_tx_status;
745	dma->device_prep_interleaved_dma = sirfsoc_dma_prep_interleaved;
746	dma->device_prep_dma_cyclic = sirfsoc_dma_prep_cyclic;
747	dma->device_slave_caps = sirfsoc_dma_device_slave_caps;
748
749	INIT_LIST_HEAD(&dma->channels);
750	dma_cap_set(DMA_SLAVE, dma->cap_mask);
751	dma_cap_set(DMA_CYCLIC, dma->cap_mask);
752	dma_cap_set(DMA_INTERLEAVE, dma->cap_mask);
753	dma_cap_set(DMA_PRIVATE, dma->cap_mask);
754
755	for (i = 0; i < dma->chancnt; i++) {
756		schan = &sdma->channels[i];
757
758		schan->chan.device = dma;
759		dma_cookie_init(&schan->chan);
760
761		INIT_LIST_HEAD(&schan->free);
762		INIT_LIST_HEAD(&schan->prepared);
763		INIT_LIST_HEAD(&schan->queued);
764		INIT_LIST_HEAD(&schan->active);
765		INIT_LIST_HEAD(&schan->completed);
766
767		spin_lock_init(&schan->lock);
768		list_add_tail(&schan->chan.device_node, &dma->channels);
769	}
770
771	tasklet_init(&sdma->tasklet, sirfsoc_dma_tasklet, (unsigned long)sdma);
772
773	/* Register DMA engine */
774	dev_set_drvdata(dev, sdma);
775
776	ret = dma_async_device_register(dma);
777	if (ret)
778		goto free_irq;
779
780	/* Device-tree DMA controller registration */
781	ret = of_dma_controller_register(dn, of_dma_sirfsoc_xlate, sdma);
782	if (ret) {
783		dev_err(dev, "failed to register DMA controller\n");
784		goto unreg_dma_dev;
785	}
786
787	pm_runtime_enable(&op->dev);
788	dev_info(dev, "initialized SIRFSOC DMAC driver\n");
789
790	return 0;
791
792unreg_dma_dev:
793	dma_async_device_unregister(dma);
794free_irq:
795	free_irq(sdma->irq, sdma);
796irq_dispose:
797	irq_dispose_mapping(sdma->irq);
798	return ret;
799}
800
801static int sirfsoc_dma_remove(struct platform_device *op)
802{
803	struct device *dev = &op->dev;
804	struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
805
806	of_dma_controller_free(op->dev.of_node);
807	dma_async_device_unregister(&sdma->dma);
808	free_irq(sdma->irq, sdma);
809	irq_dispose_mapping(sdma->irq);
810	pm_runtime_disable(&op->dev);
811	if (!pm_runtime_status_suspended(&op->dev))
812		sirfsoc_dma_runtime_suspend(&op->dev);
813
814	return 0;
815}
816
817static int sirfsoc_dma_runtime_suspend(struct device *dev)
818{
819	struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
820
821	clk_disable_unprepare(sdma->clk);
822	return 0;
823}
824
825static int sirfsoc_dma_runtime_resume(struct device *dev)
826{
827	struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
828	int ret;
829
830	ret = clk_prepare_enable(sdma->clk);
831	if (ret < 0) {
832		dev_err(dev, "clk_enable failed: %d\n", ret);
833		return ret;
834	}
835	return 0;
836}
837
838static int sirfsoc_dma_pm_suspend(struct device *dev)
839{
840	struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
841	struct sirfsoc_dma_regs *save = &sdma->regs_save;
842	struct sirfsoc_dma_desc *sdesc;
843	struct sirfsoc_dma_chan *schan;
844	int ch;
845	int ret;
846
847	/*
848	 * if we were runtime-suspended before, resume to enable clock
849	 * before accessing register
850	 */
851	if (pm_runtime_status_suspended(dev)) {
852		ret = sirfsoc_dma_runtime_resume(dev);
853		if (ret < 0)
854			return ret;
855	}
856
857	/*
858	 * DMA controller will lose all registers while suspending
859	 * so we need to save registers for active channels
860	 */
861	for (ch = 0; ch < SIRFSOC_DMA_CHANNELS; ch++) {
862		schan = &sdma->channels[ch];
863		if (list_empty(&schan->active))
864			continue;
865		sdesc = list_first_entry(&schan->active,
866			struct sirfsoc_dma_desc,
867			node);
868		save->ctrl[ch] = readl_relaxed(sdma->base +
869			ch * 0x10 + SIRFSOC_DMA_CH_CTRL);
870	}
871	save->interrupt_en = readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN);
872
873	/* Disable clock */
874	sirfsoc_dma_runtime_suspend(dev);
875
876	return 0;
877}
878
879static int sirfsoc_dma_pm_resume(struct device *dev)
880{
881	struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
882	struct sirfsoc_dma_regs *save = &sdma->regs_save;
883	struct sirfsoc_dma_desc *sdesc;
884	struct sirfsoc_dma_chan *schan;
885	int ch;
886	int ret;
887
888	/* Enable clock before accessing register */
889	ret = sirfsoc_dma_runtime_resume(dev);
890	if (ret < 0)
891		return ret;
892
893	writel_relaxed(save->interrupt_en, sdma->base + SIRFSOC_DMA_INT_EN);
894	for (ch = 0; ch < SIRFSOC_DMA_CHANNELS; ch++) {
895		schan = &sdma->channels[ch];
896		if (list_empty(&schan->active))
897			continue;
898		sdesc = list_first_entry(&schan->active,
899			struct sirfsoc_dma_desc,
900			node);
901		writel_relaxed(sdesc->width,
902			sdma->base + SIRFSOC_DMA_WIDTH_0 + ch * 4);
903		writel_relaxed(sdesc->xlen,
904			sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_XLEN);
905		writel_relaxed(sdesc->ylen,
906			sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_YLEN);
907		writel_relaxed(save->ctrl[ch],
908			sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_CTRL);
909		writel_relaxed(sdesc->addr >> 2,
910			sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_ADDR);
911	}
912
913	/* if we were runtime-suspended before, suspend again */
914	if (pm_runtime_status_suspended(dev))
915		sirfsoc_dma_runtime_suspend(dev);
916
917	return 0;
918}
919
920static const struct dev_pm_ops sirfsoc_dma_pm_ops = {
921	SET_RUNTIME_PM_OPS(sirfsoc_dma_runtime_suspend, sirfsoc_dma_runtime_resume, NULL)
922	SET_SYSTEM_SLEEP_PM_OPS(sirfsoc_dma_pm_suspend, sirfsoc_dma_pm_resume)
923};
924
925static struct of_device_id sirfsoc_dma_match[] = {
926	{ .compatible = "sirf,prima2-dmac", },
927	{ .compatible = "sirf,marco-dmac", },
928	{},
929};
930
931static struct platform_driver sirfsoc_dma_driver = {
932	.probe		= sirfsoc_dma_probe,
933	.remove		= sirfsoc_dma_remove,
934	.driver = {
935		.name = DRV_NAME,
936		.owner = THIS_MODULE,
937		.pm = &sirfsoc_dma_pm_ops,
938		.of_match_table	= sirfsoc_dma_match,
939	},
940};
941
942static __init int sirfsoc_dma_init(void)
943{
944	return platform_driver_register(&sirfsoc_dma_driver);
945}
946
947static void __exit sirfsoc_dma_exit(void)
948{
949	platform_driver_unregister(&sirfsoc_dma_driver);
950}
951
952subsys_initcall(sirfsoc_dma_init);
953module_exit(sirfsoc_dma_exit);
954
955MODULE_AUTHOR("Rongjun Ying <rongjun.ying@csr.com>, "
956	"Barry Song <baohua.song@csr.com>");
957MODULE_DESCRIPTION("SIRFSOC DMA control driver");
958MODULE_LICENSE("GPL v2");