fsldma.c revision f79abb627f033c85a6088231f20c85bc4a9bd757
1/*
2 * Freescale MPC85xx, MPC83xx DMA Engine support
3 *
4 * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
5 *
6 * Author:
7 *   Zhang Wei <wei.zhang@freescale.com>, Jul 2007
8 *   Ebony Zhu <ebony.zhu@freescale.com>, May 2007
9 *
10 * Description:
11 *   DMA engine driver for Freescale MPC8540 DMA controller, which is
12 *   also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc.
13 *   The support for MPC8349 DMA contorller is also added.
14 *
15 * This is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
19 *
20 */
21
22#include <linux/init.h>
23#include <linux/module.h>
24#include <linux/pci.h>
25#include <linux/interrupt.h>
26#include <linux/dmaengine.h>
27#include <linux/delay.h>
28#include <linux/dma-mapping.h>
29#include <linux/dmapool.h>
30#include <linux/of_platform.h>
31
32#include "fsldma.h"
33
34static void dma_init(struct fsl_dma_chan *fsl_chan)
35{
36	/* Reset the channel */
37	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, 0, 32);
38
39	switch (fsl_chan->feature & FSL_DMA_IP_MASK) {
40	case FSL_DMA_IP_85XX:
41		/* Set the channel to below modes:
42		 * EIE - Error interrupt enable
43		 * EOSIE - End of segments interrupt enable (basic mode)
44		 * EOLNIE - End of links interrupt enable
45		 */
46		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EIE
47				| FSL_DMA_MR_EOLNIE | FSL_DMA_MR_EOSIE, 32);
48		break;
49	case FSL_DMA_IP_83XX:
50		/* Set the channel to below modes:
51		 * EOTIE - End-of-transfer interrupt enable
52		 */
53		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE,
54				32);
55		break;
56	}
57
58}
59
60static void set_sr(struct fsl_dma_chan *fsl_chan, u32 val)
61{
62	DMA_OUT(fsl_chan, &fsl_chan->reg_base->sr, val, 32);
63}
64
65static u32 get_sr(struct fsl_dma_chan *fsl_chan)
66{
67	return DMA_IN(fsl_chan, &fsl_chan->reg_base->sr, 32);
68}
69
70static void set_desc_cnt(struct fsl_dma_chan *fsl_chan,
71				struct fsl_dma_ld_hw *hw, u32 count)
72{
73	hw->count = CPU_TO_DMA(fsl_chan, count, 32);
74}
75
76static void set_desc_src(struct fsl_dma_chan *fsl_chan,
77				struct fsl_dma_ld_hw *hw, dma_addr_t src)
78{
79	u64 snoop_bits;
80
81	snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
82		? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0;
83	hw->src_addr = CPU_TO_DMA(fsl_chan, snoop_bits | src, 64);
84}
85
86static void set_desc_dest(struct fsl_dma_chan *fsl_chan,
87				struct fsl_dma_ld_hw *hw, dma_addr_t dest)
88{
89	u64 snoop_bits;
90
91	snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
92		? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0;
93	hw->dst_addr = CPU_TO_DMA(fsl_chan, snoop_bits | dest, 64);
94}
95
96static void set_desc_next(struct fsl_dma_chan *fsl_chan,
97				struct fsl_dma_ld_hw *hw, dma_addr_t next)
98{
99	u64 snoop_bits;
100
101	snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
102		? FSL_DMA_SNEN : 0;
103	hw->next_ln_addr = CPU_TO_DMA(fsl_chan, snoop_bits | next, 64);
104}
105
106static void set_cdar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
107{
108	DMA_OUT(fsl_chan, &fsl_chan->reg_base->cdar, addr | FSL_DMA_SNEN, 64);
109}
110
111static dma_addr_t get_cdar(struct fsl_dma_chan *fsl_chan)
112{
113	return DMA_IN(fsl_chan, &fsl_chan->reg_base->cdar, 64) & ~FSL_DMA_SNEN;
114}
115
116static void set_ndar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
117{
118	DMA_OUT(fsl_chan, &fsl_chan->reg_base->ndar, addr, 64);
119}
120
121static dma_addr_t get_ndar(struct fsl_dma_chan *fsl_chan)
122{
123	return DMA_IN(fsl_chan, &fsl_chan->reg_base->ndar, 64);
124}
125
126static u32 get_bcr(struct fsl_dma_chan *fsl_chan)
127{
128	return DMA_IN(fsl_chan, &fsl_chan->reg_base->bcr, 32);
129}
130
131static int dma_is_idle(struct fsl_dma_chan *fsl_chan)
132{
133	u32 sr = get_sr(fsl_chan);
134	return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH);
135}
136
137static void dma_start(struct fsl_dma_chan *fsl_chan)
138{
139	u32 mr_set = 0;;
140
141	if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
142		DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
143		mr_set |= FSL_DMA_MR_EMP_EN;
144	} else
145		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
146			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
147				& ~FSL_DMA_MR_EMP_EN, 32);
148
149	if (fsl_chan->feature & FSL_DMA_CHAN_START_EXT)
150		mr_set |= FSL_DMA_MR_EMS_EN;
151	else
152		mr_set |= FSL_DMA_MR_CS;
153
154	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
155			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
156			| mr_set, 32);
157}
158
159static void dma_halt(struct fsl_dma_chan *fsl_chan)
160{
161	int i = 0;
162	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
163		DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) | FSL_DMA_MR_CA,
164		32);
165	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
166		DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) & ~(FSL_DMA_MR_CS
167		| FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA), 32);
168
169	while (!dma_is_idle(fsl_chan) && (i++ < 100))
170		udelay(10);
171	if (i >= 100 && !dma_is_idle(fsl_chan))
172		dev_err(fsl_chan->dev, "DMA halt timeout!\n");
173}
174
175static void set_ld_eol(struct fsl_dma_chan *fsl_chan,
176			struct fsl_desc_sw *desc)
177{
178	desc->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
179		DMA_TO_CPU(fsl_chan, desc->hw.next_ln_addr, 64)	| FSL_DMA_EOL,
180		64);
181}
182
183static void append_ld_queue(struct fsl_dma_chan *fsl_chan,
184		struct fsl_desc_sw *new_desc)
185{
186	struct fsl_desc_sw *queue_tail = to_fsl_desc(fsl_chan->ld_queue.prev);
187
188	if (list_empty(&fsl_chan->ld_queue))
189		return;
190
191	/* Link to the new descriptor physical address and
192	 * Enable End-of-segment interrupt for
193	 * the last link descriptor.
194	 * (the previous node's next link descriptor)
195	 *
196	 * For FSL_DMA_IP_83xx, the snoop enable bit need be set.
197	 */
198	queue_tail->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
199			new_desc->async_tx.phys | FSL_DMA_EOSIE |
200			(((fsl_chan->feature & FSL_DMA_IP_MASK)
201				== FSL_DMA_IP_83XX) ? FSL_DMA_SNEN : 0), 64);
202}
203
204/**
205 * fsl_chan_set_src_loop_size - Set source address hold transfer size
206 * @fsl_chan : Freescale DMA channel
207 * @size     : Address loop size, 0 for disable loop
208 *
209 * The set source address hold transfer size. The source
210 * address hold or loop transfer size is when the DMA transfer
211 * data from source address (SA), if the loop size is 4, the DMA will
212 * read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA,
213 * SA + 1 ... and so on.
214 */
215static void fsl_chan_set_src_loop_size(struct fsl_dma_chan *fsl_chan, int size)
216{
217	switch (size) {
218	case 0:
219		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
220			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
221			(~FSL_DMA_MR_SAHE), 32);
222		break;
223	case 1:
224	case 2:
225	case 4:
226	case 8:
227		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
228			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
229			FSL_DMA_MR_SAHE | (__ilog2(size) << 14),
230			32);
231		break;
232	}
233}
234
235/**
236 * fsl_chan_set_dest_loop_size - Set destination address hold transfer size
237 * @fsl_chan : Freescale DMA channel
238 * @size     : Address loop size, 0 for disable loop
239 *
240 * The set destination address hold transfer size. The destination
241 * address hold or loop transfer size is when the DMA transfer
242 * data to destination address (TA), if the loop size is 4, the DMA will
243 * write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA,
244 * TA + 1 ... and so on.
245 */
246static void fsl_chan_set_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
247{
248	switch (size) {
249	case 0:
250		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
251			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
252			(~FSL_DMA_MR_DAHE), 32);
253		break;
254	case 1:
255	case 2:
256	case 4:
257	case 8:
258		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
259			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
260			FSL_DMA_MR_DAHE | (__ilog2(size) << 16),
261			32);
262		break;
263	}
264}
265
266/**
267 * fsl_chan_toggle_ext_pause - Toggle channel external pause status
268 * @fsl_chan : Freescale DMA channel
269 * @size     : Pause control size, 0 for disable external pause control.
270 *             The maximum is 1024.
271 *
272 * The Freescale DMA channel can be controlled by the external
273 * signal DREQ#. The pause control size is how many bytes are allowed
274 * to transfer before pausing the channel, after which a new assertion
275 * of DREQ# resumes channel operation.
276 */
277static void fsl_chan_toggle_ext_pause(struct fsl_dma_chan *fsl_chan, int size)
278{
279	if (size > 1024)
280		return;
281
282	if (size) {
283		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
284			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
285				| ((__ilog2(size) << 24) & 0x0f000000),
286			32);
287		fsl_chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
288	} else
289		fsl_chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
290}
291
292/**
293 * fsl_chan_toggle_ext_start - Toggle channel external start status
294 * @fsl_chan : Freescale DMA channel
295 * @enable   : 0 is disabled, 1 is enabled.
296 *
297 * If enable the external start, the channel can be started by an
298 * external DMA start pin. So the dma_start() does not start the
299 * transfer immediately. The DMA channel will wait for the
300 * control pin asserted.
301 */
302static void fsl_chan_toggle_ext_start(struct fsl_dma_chan *fsl_chan, int enable)
303{
304	if (enable)
305		fsl_chan->feature |= FSL_DMA_CHAN_START_EXT;
306	else
307		fsl_chan->feature &= ~FSL_DMA_CHAN_START_EXT;
308}
309
310static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
311{
312	struct fsl_desc_sw *desc = tx_to_fsl_desc(tx);
313	struct fsl_dma_chan *fsl_chan = to_fsl_chan(tx->chan);
314	unsigned long flags;
315	dma_cookie_t cookie;
316
317	/* cookie increment and adding to ld_queue must be atomic */
318	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
319
320	cookie = fsl_chan->common.cookie;
321	cookie++;
322	if (cookie < 0)
323		cookie = 1;
324	desc->async_tx.cookie = cookie;
325	fsl_chan->common.cookie = desc->async_tx.cookie;
326
327	append_ld_queue(fsl_chan, desc);
328	list_splice_init(&desc->async_tx.tx_list, fsl_chan->ld_queue.prev);
329
330	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
331
332	return cookie;
333}
334
335/**
336 * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool.
337 * @fsl_chan : Freescale DMA channel
338 *
339 * Return - The descriptor allocated. NULL for failed.
340 */
341static struct fsl_desc_sw *fsl_dma_alloc_descriptor(
342					struct fsl_dma_chan *fsl_chan)
343{
344	dma_addr_t pdesc;
345	struct fsl_desc_sw *desc_sw;
346
347	desc_sw = dma_pool_alloc(fsl_chan->desc_pool, GFP_ATOMIC, &pdesc);
348	if (desc_sw) {
349		memset(desc_sw, 0, sizeof(struct fsl_desc_sw));
350		dma_async_tx_descriptor_init(&desc_sw->async_tx,
351						&fsl_chan->common);
352		desc_sw->async_tx.tx_submit = fsl_dma_tx_submit;
353		INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
354		desc_sw->async_tx.phys = pdesc;
355	}
356
357	return desc_sw;
358}
359
360
361/**
362 * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel.
363 * @fsl_chan : Freescale DMA channel
364 *
365 * This function will create a dma pool for descriptor allocation.
366 *
367 * Return - The number of descriptors allocated.
368 */
369static int fsl_dma_alloc_chan_resources(struct dma_chan *chan)
370{
371	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
372	LIST_HEAD(tmp_list);
373
374	/* We need the descriptor to be aligned to 32bytes
375	 * for meeting FSL DMA specification requirement.
376	 */
377	fsl_chan->desc_pool = dma_pool_create("fsl_dma_engine_desc_pool",
378			fsl_chan->dev, sizeof(struct fsl_desc_sw),
379			32, 0);
380	if (!fsl_chan->desc_pool) {
381		dev_err(fsl_chan->dev, "No memory for channel %d "
382			"descriptor dma pool.\n", fsl_chan->id);
383		return 0;
384	}
385
386	return 1;
387}
388
389/**
390 * fsl_dma_free_chan_resources - Free all resources of the channel.
391 * @fsl_chan : Freescale DMA channel
392 */
393static void fsl_dma_free_chan_resources(struct dma_chan *chan)
394{
395	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
396	struct fsl_desc_sw *desc, *_desc;
397	unsigned long flags;
398
399	dev_dbg(fsl_chan->dev, "Free all channel resources.\n");
400	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
401	list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
402#ifdef FSL_DMA_LD_DEBUG
403		dev_dbg(fsl_chan->dev,
404				"LD %p will be released.\n", desc);
405#endif
406		list_del(&desc->node);
407		/* free link descriptor */
408		dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
409	}
410	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
411	dma_pool_destroy(fsl_chan->desc_pool);
412}
413
414static struct dma_async_tx_descriptor *
415fsl_dma_prep_interrupt(struct dma_chan *chan)
416{
417	struct fsl_dma_chan *fsl_chan;
418	struct fsl_desc_sw *new;
419
420	if (!chan)
421		return NULL;
422
423	fsl_chan = to_fsl_chan(chan);
424
425	new = fsl_dma_alloc_descriptor(fsl_chan);
426	if (!new) {
427		dev_err(fsl_chan->dev, "No free memory for link descriptor\n");
428		return NULL;
429	}
430
431	new->async_tx.cookie = -EBUSY;
432	new->async_tx.ack = 0;
433
434	/* Insert the link descriptor to the LD ring */
435	list_add_tail(&new->node, &new->async_tx.tx_list);
436
437	/* Set End-of-link to the last link descriptor of new list*/
438	set_ld_eol(fsl_chan, new);
439
440	return &new->async_tx;
441}
442
443static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
444	struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
445	size_t len, unsigned long flags)
446{
447	struct fsl_dma_chan *fsl_chan;
448	struct fsl_desc_sw *first = NULL, *prev = NULL, *new;
449	size_t copy;
450	LIST_HEAD(link_chain);
451
452	if (!chan)
453		return NULL;
454
455	if (!len)
456		return NULL;
457
458	fsl_chan = to_fsl_chan(chan);
459
460	do {
461
462		/* Allocate the link descriptor from DMA pool */
463		new = fsl_dma_alloc_descriptor(fsl_chan);
464		if (!new) {
465			dev_err(fsl_chan->dev,
466					"No free memory for link descriptor\n");
467			return NULL;
468		}
469#ifdef FSL_DMA_LD_DEBUG
470		dev_dbg(fsl_chan->dev, "new link desc alloc %p\n", new);
471#endif
472
473		copy = min(len, (size_t)FSL_DMA_BCR_MAX_CNT);
474
475		set_desc_cnt(fsl_chan, &new->hw, copy);
476		set_desc_src(fsl_chan, &new->hw, dma_src);
477		set_desc_dest(fsl_chan, &new->hw, dma_dest);
478
479		if (!first)
480			first = new;
481		else
482			set_desc_next(fsl_chan, &prev->hw, new->async_tx.phys);
483
484		new->async_tx.cookie = 0;
485		new->async_tx.ack = 1;
486
487		prev = new;
488		len -= copy;
489		dma_src += copy;
490		dma_dest += copy;
491
492		/* Insert the link descriptor to the LD ring */
493		list_add_tail(&new->node, &first->async_tx.tx_list);
494	} while (len);
495
496	new->async_tx.ack = 0; /* client is in control of this ack */
497	new->async_tx.cookie = -EBUSY;
498
499	/* Set End-of-link to the last link descriptor of new list*/
500	set_ld_eol(fsl_chan, new);
501
502	return first ? &first->async_tx : NULL;
503}
504
505/**
506 * fsl_dma_update_completed_cookie - Update the completed cookie.
507 * @fsl_chan : Freescale DMA channel
508 */
509static void fsl_dma_update_completed_cookie(struct fsl_dma_chan *fsl_chan)
510{
511	struct fsl_desc_sw *cur_desc, *desc;
512	dma_addr_t ld_phy;
513
514	ld_phy = get_cdar(fsl_chan) & FSL_DMA_NLDA_MASK;
515
516	if (ld_phy) {
517		cur_desc = NULL;
518		list_for_each_entry(desc, &fsl_chan->ld_queue, node)
519			if (desc->async_tx.phys == ld_phy) {
520				cur_desc = desc;
521				break;
522			}
523
524		if (cur_desc && cur_desc->async_tx.cookie) {
525			if (dma_is_idle(fsl_chan))
526				fsl_chan->completed_cookie =
527					cur_desc->async_tx.cookie;
528			else
529				fsl_chan->completed_cookie =
530					cur_desc->async_tx.cookie - 1;
531		}
532	}
533}
534
535/**
536 * fsl_chan_ld_cleanup - Clean up link descriptors
537 * @fsl_chan : Freescale DMA channel
538 *
539 * This function clean up the ld_queue of DMA channel.
540 * If 'in_intr' is set, the function will move the link descriptor to
541 * the recycle list. Otherwise, free it directly.
542 */
543static void fsl_chan_ld_cleanup(struct fsl_dma_chan *fsl_chan)
544{
545	struct fsl_desc_sw *desc, *_desc;
546	unsigned long flags;
547
548	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
549
550	dev_dbg(fsl_chan->dev, "chan completed_cookie = %d\n",
551			fsl_chan->completed_cookie);
552	list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
553		dma_async_tx_callback callback;
554		void *callback_param;
555
556		if (dma_async_is_complete(desc->async_tx.cookie,
557			    fsl_chan->completed_cookie, fsl_chan->common.cookie)
558				== DMA_IN_PROGRESS)
559			break;
560
561		callback = desc->async_tx.callback;
562		callback_param = desc->async_tx.callback_param;
563
564		/* Remove from ld_queue list */
565		list_del(&desc->node);
566
567		dev_dbg(fsl_chan->dev, "link descriptor %p will be recycle.\n",
568				desc);
569		dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
570
571		/* Run the link descriptor callback function */
572		if (callback) {
573			spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
574			dev_dbg(fsl_chan->dev, "link descriptor %p callback\n",
575					desc);
576			callback(callback_param);
577			spin_lock_irqsave(&fsl_chan->desc_lock, flags);
578		}
579	}
580	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
581}
582
583/**
584 * fsl_chan_xfer_ld_queue - Transfer link descriptors in channel ld_queue.
585 * @fsl_chan : Freescale DMA channel
586 */
587static void fsl_chan_xfer_ld_queue(struct fsl_dma_chan *fsl_chan)
588{
589	struct list_head *ld_node;
590	dma_addr_t next_dest_addr;
591	unsigned long flags;
592
593	if (!dma_is_idle(fsl_chan))
594		return;
595
596	dma_halt(fsl_chan);
597
598	/* If there are some link descriptors
599	 * not transfered in queue. We need to start it.
600	 */
601	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
602
603	/* Find the first un-transfer desciptor */
604	for (ld_node = fsl_chan->ld_queue.next;
605		(ld_node != &fsl_chan->ld_queue)
606			&& (dma_async_is_complete(
607				to_fsl_desc(ld_node)->async_tx.cookie,
608				fsl_chan->completed_cookie,
609				fsl_chan->common.cookie) == DMA_SUCCESS);
610		ld_node = ld_node->next);
611
612	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
613
614	if (ld_node != &fsl_chan->ld_queue) {
615		/* Get the ld start address from ld_queue */
616		next_dest_addr = to_fsl_desc(ld_node)->async_tx.phys;
617		dev_dbg(fsl_chan->dev, "xfer LDs staring from %p\n",
618				(void *)next_dest_addr);
619		set_cdar(fsl_chan, next_dest_addr);
620		dma_start(fsl_chan);
621	} else {
622		set_cdar(fsl_chan, 0);
623		set_ndar(fsl_chan, 0);
624	}
625}
626
627/**
628 * fsl_dma_memcpy_issue_pending - Issue the DMA start command
629 * @fsl_chan : Freescale DMA channel
630 */
631static void fsl_dma_memcpy_issue_pending(struct dma_chan *chan)
632{
633	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
634
635#ifdef FSL_DMA_LD_DEBUG
636	struct fsl_desc_sw *ld;
637	unsigned long flags;
638
639	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
640	if (list_empty(&fsl_chan->ld_queue)) {
641		spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
642		return;
643	}
644
645	dev_dbg(fsl_chan->dev, "--memcpy issue--\n");
646	list_for_each_entry(ld, &fsl_chan->ld_queue, node) {
647		int i;
648		dev_dbg(fsl_chan->dev, "Ch %d, LD %08x\n",
649				fsl_chan->id, ld->async_tx.phys);
650		for (i = 0; i < 8; i++)
651			dev_dbg(fsl_chan->dev, "LD offset %d: %08x\n",
652					i, *(((u32 *)&ld->hw) + i));
653	}
654	dev_dbg(fsl_chan->dev, "----------------\n");
655	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
656#endif
657
658	fsl_chan_xfer_ld_queue(fsl_chan);
659}
660
661static void fsl_dma_dependency_added(struct dma_chan *chan)
662{
663	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
664
665	fsl_chan_ld_cleanup(fsl_chan);
666}
667
668/**
669 * fsl_dma_is_complete - Determine the DMA status
670 * @fsl_chan : Freescale DMA channel
671 */
672static enum dma_status fsl_dma_is_complete(struct dma_chan *chan,
673					dma_cookie_t cookie,
674					dma_cookie_t *done,
675					dma_cookie_t *used)
676{
677	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
678	dma_cookie_t last_used;
679	dma_cookie_t last_complete;
680
681	fsl_chan_ld_cleanup(fsl_chan);
682
683	last_used = chan->cookie;
684	last_complete = fsl_chan->completed_cookie;
685
686	if (done)
687		*done = last_complete;
688
689	if (used)
690		*used = last_used;
691
692	return dma_async_is_complete(cookie, last_complete, last_used);
693}
694
695static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
696{
697	struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
698	u32 stat;
699
700	stat = get_sr(fsl_chan);
701	dev_dbg(fsl_chan->dev, "event: channel %d, stat = 0x%x\n",
702						fsl_chan->id, stat);
703	set_sr(fsl_chan, stat);		/* Clear the event register */
704
705	stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH);
706	if (!stat)
707		return IRQ_NONE;
708
709	if (stat & FSL_DMA_SR_TE)
710		dev_err(fsl_chan->dev, "Transfer Error!\n");
711
712	/* Programming Error
713	 * The DMA_INTERRUPT async_tx is a NULL transfer, which will
714	 * triger a PE interrupt.
715	 */
716	if (stat & FSL_DMA_SR_PE) {
717		dev_dbg(fsl_chan->dev, "event: Programming Error INT\n");
718		if (get_bcr(fsl_chan) == 0) {
719			/* BCR register is 0, this is a DMA_INTERRUPT async_tx.
720			 * Now, update the completed cookie, and continue the
721			 * next uncompleted transfer.
722			 */
723			fsl_dma_update_completed_cookie(fsl_chan);
724			fsl_chan_xfer_ld_queue(fsl_chan);
725		}
726		stat &= ~FSL_DMA_SR_PE;
727	}
728
729	/* If the link descriptor segment transfer finishes,
730	 * we will recycle the used descriptor.
731	 */
732	if (stat & FSL_DMA_SR_EOSI) {
733		dev_dbg(fsl_chan->dev, "event: End-of-segments INT\n");
734		dev_dbg(fsl_chan->dev, "event: clndar %p, nlndar %p\n",
735			(void *)get_cdar(fsl_chan), (void *)get_ndar(fsl_chan));
736		stat &= ~FSL_DMA_SR_EOSI;
737		fsl_dma_update_completed_cookie(fsl_chan);
738	}
739
740	/* If it current transfer is the end-of-transfer,
741	 * we should clear the Channel Start bit for
742	 * prepare next transfer.
743	 */
744	if (stat & (FSL_DMA_SR_EOLNI | FSL_DMA_SR_EOCDI)) {
745		dev_dbg(fsl_chan->dev, "event: End-of-link INT\n");
746		stat &= ~FSL_DMA_SR_EOLNI;
747		fsl_chan_xfer_ld_queue(fsl_chan);
748	}
749
750	if (stat)
751		dev_dbg(fsl_chan->dev, "event: unhandled sr 0x%02x\n",
752					stat);
753
754	dev_dbg(fsl_chan->dev, "event: Exit\n");
755	tasklet_schedule(&fsl_chan->tasklet);
756	return IRQ_HANDLED;
757}
758
759static irqreturn_t fsl_dma_do_interrupt(int irq, void *data)
760{
761	struct fsl_dma_device *fdev = (struct fsl_dma_device *)data;
762	u32 gsr;
763	int ch_nr;
764
765	gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->reg_base)
766			: in_le32(fdev->reg_base);
767	ch_nr = (32 - ffs(gsr)) / 8;
768
769	return fdev->chan[ch_nr] ? fsl_dma_chan_do_interrupt(irq,
770			fdev->chan[ch_nr]) : IRQ_NONE;
771}
772
773static void dma_do_tasklet(unsigned long data)
774{
775	struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
776	fsl_chan_ld_cleanup(fsl_chan);
777}
778
779#ifdef FSL_DMA_CALLBACKTEST
780static void fsl_dma_callback_test(struct fsl_dma_chan *fsl_chan)
781{
782	if (fsl_chan)
783		dev_info(fsl_chan->dev, "selftest: callback is ok!\n");
784}
785#endif
786
787#ifdef CONFIG_FSL_DMA_SELFTEST
788static int fsl_dma_self_test(struct fsl_dma_chan *fsl_chan)
789{
790	struct dma_chan *chan;
791	int err = 0;
792	dma_addr_t dma_dest, dma_src;
793	dma_cookie_t cookie;
794	u8 *src, *dest;
795	int i;
796	size_t test_size;
797	struct dma_async_tx_descriptor *tx1, *tx2, *tx3;
798
799	test_size = 4096;
800
801	src = kmalloc(test_size * 2, GFP_KERNEL);
802	if (!src) {
803		dev_err(fsl_chan->dev,
804				"selftest: Cannot alloc memory for test!\n");
805		err = -ENOMEM;
806		goto out;
807	}
808
809	dest = src + test_size;
810
811	for (i = 0; i < test_size; i++)
812		src[i] = (u8) i;
813
814	chan = &fsl_chan->common;
815
816	if (fsl_dma_alloc_chan_resources(chan) < 1) {
817		dev_err(fsl_chan->dev,
818				"selftest: Cannot alloc resources for DMA\n");
819		err = -ENODEV;
820		goto out;
821	}
822
823	/* TX 1 */
824	dma_src = dma_map_single(fsl_chan->dev, src, test_size / 2,
825				 DMA_TO_DEVICE);
826	dma_dest = dma_map_single(fsl_chan->dev, dest, test_size / 2,
827				  DMA_FROM_DEVICE);
828	tx1 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 2, 0);
829	async_tx_ack(tx1);
830
831	cookie = fsl_dma_tx_submit(tx1);
832	fsl_dma_memcpy_issue_pending(chan);
833	msleep(2);
834
835	if (fsl_dma_is_complete(chan, cookie, NULL, NULL) != DMA_SUCCESS) {
836		dev_err(fsl_chan->dev, "selftest: Time out!\n");
837		err = -ENODEV;
838		goto out;
839	}
840
841	/* Test free and re-alloc channel resources */
842	fsl_dma_free_chan_resources(chan);
843
844	if (fsl_dma_alloc_chan_resources(chan) < 1) {
845		dev_err(fsl_chan->dev,
846				"selftest: Cannot alloc resources for DMA\n");
847		err = -ENODEV;
848		goto free_resources;
849	}
850
851	/* Continue to test
852	 * TX 2
853	 */
854	dma_src = dma_map_single(fsl_chan->dev, src + test_size / 2,
855					test_size / 4, DMA_TO_DEVICE);
856	dma_dest = dma_map_single(fsl_chan->dev, dest + test_size / 2,
857					test_size / 4, DMA_FROM_DEVICE);
858	tx2 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 4, 0);
859	async_tx_ack(tx2);
860
861	/* TX 3 */
862	dma_src = dma_map_single(fsl_chan->dev, src + test_size * 3 / 4,
863					test_size / 4, DMA_TO_DEVICE);
864	dma_dest = dma_map_single(fsl_chan->dev, dest + test_size * 3 / 4,
865					test_size / 4, DMA_FROM_DEVICE);
866	tx3 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 4, 0);
867	async_tx_ack(tx3);
868
869	/* Interrupt tx test */
870	tx1 = fsl_dma_prep_interrupt(chan);
871	async_tx_ack(tx1);
872	cookie = fsl_dma_tx_submit(tx1);
873
874	/* Test exchanging the prepared tx sort */
875	cookie = fsl_dma_tx_submit(tx3);
876	cookie = fsl_dma_tx_submit(tx2);
877
878#ifdef FSL_DMA_CALLBACKTEST
879	if (dma_has_cap(DMA_INTERRUPT, ((struct fsl_dma_device *)
880	    dev_get_drvdata(fsl_chan->dev->parent))->common.cap_mask)) {
881		tx3->callback = fsl_dma_callback_test;
882		tx3->callback_param = fsl_chan;
883	}
884#endif
885	fsl_dma_memcpy_issue_pending(chan);
886	msleep(2);
887
888	if (fsl_dma_is_complete(chan, cookie, NULL, NULL) != DMA_SUCCESS) {
889		dev_err(fsl_chan->dev, "selftest: Time out!\n");
890		err = -ENODEV;
891		goto free_resources;
892	}
893
894	err = memcmp(src, dest, test_size);
895	if (err) {
896		for (i = 0; (*(src + i) == *(dest + i)) && (i < test_size);
897				i++);
898		dev_err(fsl_chan->dev, "selftest: Test failed, data %d/%ld is "
899				"error! src 0x%x, dest 0x%x\n",
900				i, (long)test_size, *(src + i), *(dest + i));
901	}
902
903free_resources:
904	fsl_dma_free_chan_resources(chan);
905out:
906	kfree(src);
907	return err;
908}
909#endif
910
911static int __devinit of_fsl_dma_chan_probe(struct of_device *dev,
912			const struct of_device_id *match)
913{
914	struct fsl_dma_device *fdev;
915	struct fsl_dma_chan *new_fsl_chan;
916	int err;
917
918	fdev = dev_get_drvdata(dev->dev.parent);
919	BUG_ON(!fdev);
920
921	/* alloc channel */
922	new_fsl_chan = kzalloc(sizeof(struct fsl_dma_chan), GFP_KERNEL);
923	if (!new_fsl_chan) {
924		dev_err(&dev->dev, "No free memory for allocating "
925				"dma channels!\n");
926		err = -ENOMEM;
927		goto err;
928	}
929
930	/* get dma channel register base */
931	err = of_address_to_resource(dev->node, 0, &new_fsl_chan->reg);
932	if (err) {
933		dev_err(&dev->dev, "Can't get %s property 'reg'\n",
934				dev->node->full_name);
935		goto err;
936	}
937
938	new_fsl_chan->feature = *(u32 *)match->data;
939
940	if (!fdev->feature)
941		fdev->feature = new_fsl_chan->feature;
942
943	/* If the DMA device's feature is different than its channels',
944	 * report the bug.
945	 */
946	WARN_ON(fdev->feature != new_fsl_chan->feature);
947
948	new_fsl_chan->dev = &dev->dev;
949	new_fsl_chan->reg_base = ioremap(new_fsl_chan->reg.start,
950			new_fsl_chan->reg.end - new_fsl_chan->reg.start + 1);
951
952	new_fsl_chan->id = ((new_fsl_chan->reg.start - 0x100) & 0xfff) >> 7;
953	if (new_fsl_chan->id > FSL_DMA_MAX_CHANS_PER_DEVICE) {
954		dev_err(&dev->dev, "There is no %d channel!\n",
955				new_fsl_chan->id);
956		err = -EINVAL;
957		goto err;
958	}
959	fdev->chan[new_fsl_chan->id] = new_fsl_chan;
960	tasklet_init(&new_fsl_chan->tasklet, dma_do_tasklet,
961			(unsigned long)new_fsl_chan);
962
963	/* Init the channel */
964	dma_init(new_fsl_chan);
965
966	/* Clear cdar registers */
967	set_cdar(new_fsl_chan, 0);
968
969	switch (new_fsl_chan->feature & FSL_DMA_IP_MASK) {
970	case FSL_DMA_IP_85XX:
971		new_fsl_chan->toggle_ext_start = fsl_chan_toggle_ext_start;
972		new_fsl_chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
973	case FSL_DMA_IP_83XX:
974		new_fsl_chan->set_src_loop_size = fsl_chan_set_src_loop_size;
975		new_fsl_chan->set_dest_loop_size = fsl_chan_set_dest_loop_size;
976	}
977
978	spin_lock_init(&new_fsl_chan->desc_lock);
979	INIT_LIST_HEAD(&new_fsl_chan->ld_queue);
980
981	new_fsl_chan->common.device = &fdev->common;
982
983	/* Add the channel to DMA device channel list */
984	list_add_tail(&new_fsl_chan->common.device_node,
985			&fdev->common.channels);
986	fdev->common.chancnt++;
987
988	new_fsl_chan->irq = irq_of_parse_and_map(dev->node, 0);
989	if (new_fsl_chan->irq != NO_IRQ) {
990		err = request_irq(new_fsl_chan->irq,
991					&fsl_dma_chan_do_interrupt, IRQF_SHARED,
992					"fsldma-channel", new_fsl_chan);
993		if (err) {
994			dev_err(&dev->dev, "DMA channel %s request_irq error "
995				"with return %d\n", dev->node->full_name, err);
996			goto err;
997		}
998	}
999
1000#ifdef CONFIG_FSL_DMA_SELFTEST
1001	err = fsl_dma_self_test(new_fsl_chan);
1002	if (err)
1003		goto err;
1004#endif
1005
1006	dev_info(&dev->dev, "#%d (%s), irq %d\n", new_fsl_chan->id,
1007				match->compatible, new_fsl_chan->irq);
1008
1009	return 0;
1010err:
1011	dma_halt(new_fsl_chan);
1012	iounmap(new_fsl_chan->reg_base);
1013	free_irq(new_fsl_chan->irq, new_fsl_chan);
1014	list_del(&new_fsl_chan->common.device_node);
1015	kfree(new_fsl_chan);
1016	return err;
1017}
1018
1019const u32 mpc8540_dma_ip_feature = FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN;
1020const u32 mpc8349_dma_ip_feature = FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN;
1021
1022static struct of_device_id of_fsl_dma_chan_ids[] = {
1023	{
1024		.compatible = "fsl,mpc8540-dma-channel",
1025		.data = (void *)&mpc8540_dma_ip_feature,
1026	},
1027	{
1028		.compatible = "fsl,mpc8349-dma-channel",
1029		.data = (void *)&mpc8349_dma_ip_feature,
1030	},
1031	{}
1032};
1033
1034static struct of_platform_driver of_fsl_dma_chan_driver = {
1035	.name = "of-fsl-dma-channel",
1036	.match_table = of_fsl_dma_chan_ids,
1037	.probe = of_fsl_dma_chan_probe,
1038};
1039
1040static __init int of_fsl_dma_chan_init(void)
1041{
1042	return of_register_platform_driver(&of_fsl_dma_chan_driver);
1043}
1044
1045static int __devinit of_fsl_dma_probe(struct of_device *dev,
1046			const struct of_device_id *match)
1047{
1048	int err;
1049	unsigned int irq;
1050	struct fsl_dma_device *fdev;
1051
1052	fdev = kzalloc(sizeof(struct fsl_dma_device), GFP_KERNEL);
1053	if (!fdev) {
1054		dev_err(&dev->dev, "No enough memory for 'priv'\n");
1055		err = -ENOMEM;
1056		goto err;
1057	}
1058	fdev->dev = &dev->dev;
1059	INIT_LIST_HEAD(&fdev->common.channels);
1060
1061	/* get DMA controller register base */
1062	err = of_address_to_resource(dev->node, 0, &fdev->reg);
1063	if (err) {
1064		dev_err(&dev->dev, "Can't get %s property 'reg'\n",
1065				dev->node->full_name);
1066		goto err;
1067	}
1068
1069	dev_info(&dev->dev, "Probe the Freescale DMA driver for %s "
1070			"controller at %p...\n",
1071			match->compatible, (void *)fdev->reg.start);
1072	fdev->reg_base = ioremap(fdev->reg.start, fdev->reg.end
1073						- fdev->reg.start + 1);
1074
1075	dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
1076	dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask);
1077	fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources;
1078	fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources;
1079	fdev->common.device_prep_dma_interrupt = fsl_dma_prep_interrupt;
1080	fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
1081	fdev->common.device_is_tx_complete = fsl_dma_is_complete;
1082	fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
1083	fdev->common.device_dependency_added = fsl_dma_dependency_added;
1084	fdev->common.dev = &dev->dev;
1085
1086	irq = irq_of_parse_and_map(dev->node, 0);
1087	if (irq != NO_IRQ) {
1088		err = request_irq(irq, &fsl_dma_do_interrupt, IRQF_SHARED,
1089					"fsldma-device", fdev);
1090		if (err) {
1091			dev_err(&dev->dev, "DMA device request_irq error "
1092				"with return %d\n", err);
1093			goto err;
1094		}
1095	}
1096
1097	dev_set_drvdata(&(dev->dev), fdev);
1098	of_platform_bus_probe(dev->node, of_fsl_dma_chan_ids, &dev->dev);
1099
1100	dma_async_device_register(&fdev->common);
1101	return 0;
1102
1103err:
1104	iounmap(fdev->reg_base);
1105	kfree(fdev);
1106	return err;
1107}
1108
1109static struct of_device_id of_fsl_dma_ids[] = {
1110	{ .compatible = "fsl,mpc8540-dma", },
1111	{ .compatible = "fsl,mpc8349-dma", },
1112	{}
1113};
1114
1115static struct of_platform_driver of_fsl_dma_driver = {
1116	.name = "of-fsl-dma",
1117	.match_table = of_fsl_dma_ids,
1118	.probe = of_fsl_dma_probe,
1119};
1120
1121static __init int of_fsl_dma_init(void)
1122{
1123	return of_register_platform_driver(&of_fsl_dma_driver);
1124}
1125
1126subsys_initcall(of_fsl_dma_chan_init);
1127subsys_initcall(of_fsl_dma_init);
1128