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1/*
2 * driver/dma/coh901318.c
3 *
4 * Copyright (C) 2007-2009 ST-Ericsson
5 * License terms: GNU General Public License (GPL) version 2
6 * DMA driver for COH 901 318
7 * Author: Per Friden <per.friden@stericsson.com>
8 */
9
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/kernel.h> /* printk() */
13#include <linux/fs.h> /* everything... */
14#include <linux/slab.h> /* kmalloc() */
15#include <linux/dmaengine.h>
16#include <linux/platform_device.h>
17#include <linux/device.h>
18#include <linux/irqreturn.h>
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/uaccess.h>
22#include <linux/debugfs.h>
23#include <mach/coh901318.h>
24
25#include "coh901318_lli.h"
26
27#define COHC_2_DEV(cohc) (&cohc->chan.dev->device)
28
29#ifdef VERBOSE_DEBUG
30#define COH_DBG(x) ({ if (1) x; 0; })
31#else
32#define COH_DBG(x) ({ if (0) x; 0; })
33#endif
34
35struct coh901318_desc {
36	struct dma_async_tx_descriptor desc;
37	struct list_head node;
38	struct scatterlist *sg;
39	unsigned int sg_len;
40	struct coh901318_lli *lli;
41	enum dma_data_direction dir;
42	unsigned long flags;
43};
44
45struct coh901318_base {
46	struct device *dev;
47	void __iomem *virtbase;
48	struct coh901318_pool pool;
49	struct powersave pm;
50	struct dma_device dma_slave;
51	struct dma_device dma_memcpy;
52	struct coh901318_chan *chans;
53	struct coh901318_platform *platform;
54};
55
56struct coh901318_chan {
57	spinlock_t lock;
58	int allocated;
59	int completed;
60	int id;
61	int stopped;
62
63	struct work_struct free_work;
64	struct dma_chan chan;
65
66	struct tasklet_struct tasklet;
67
68	struct list_head active;
69	struct list_head queue;
70	struct list_head free;
71
72	unsigned long nbr_active_done;
73	unsigned long busy;
74
75	u32 runtime_addr;
76	u32 runtime_ctrl;
77
78	struct coh901318_base *base;
79};
80
81static void coh901318_list_print(struct coh901318_chan *cohc,
82				 struct coh901318_lli *lli)
83{
84	struct coh901318_lli *l = lli;
85	int i = 0;
86
87	while (l) {
88		dev_vdbg(COHC_2_DEV(cohc), "i %d, lli %p, ctrl 0x%x, src 0x%x"
89			 ", dst 0x%x, link 0x%x virt_link_addr 0x%p\n",
90			 i, l, l->control, l->src_addr, l->dst_addr,
91			 l->link_addr, l->virt_link_addr);
92		i++;
93		l = l->virt_link_addr;
94	}
95}
96
97#ifdef CONFIG_DEBUG_FS
98
99#define COH901318_DEBUGFS_ASSIGN(x, y) (x = y)
100
101static struct coh901318_base *debugfs_dma_base;
102static struct dentry *dma_dentry;
103
104static int coh901318_debugfs_open(struct inode *inode, struct file *file)
105{
106
107	file->private_data = inode->i_private;
108	return 0;
109}
110
111static int coh901318_debugfs_read(struct file *file, char __user *buf,
112				  size_t count, loff_t *f_pos)
113{
114	u64 started_channels = debugfs_dma_base->pm.started_channels;
115	int pool_count = debugfs_dma_base->pool.debugfs_pool_counter;
116	int i;
117	int ret = 0;
118	char *dev_buf;
119	char *tmp;
120	int dev_size;
121
122	dev_buf = kmalloc(4*1024, GFP_KERNEL);
123	if (dev_buf == NULL)
124		goto err_kmalloc;
125	tmp = dev_buf;
126
127	tmp += sprintf(tmp, "DMA -- enabled dma channels\n");
128
129	for (i = 0; i < debugfs_dma_base->platform->max_channels; i++)
130		if (started_channels & (1 << i))
131			tmp += sprintf(tmp, "channel %d\n", i);
132
133	tmp += sprintf(tmp, "Pool alloc nbr %d\n", pool_count);
134	dev_size = tmp  - dev_buf;
135
136	/* No more to read if offset != 0 */
137	if (*f_pos > dev_size)
138		goto out;
139
140	if (count > dev_size - *f_pos)
141		count = dev_size - *f_pos;
142
143	if (copy_to_user(buf, dev_buf + *f_pos, count))
144		ret = -EINVAL;
145	ret = count;
146	*f_pos += count;
147
148 out:
149	kfree(dev_buf);
150	return ret;
151
152 err_kmalloc:
153	return 0;
154}
155
156static const struct file_operations coh901318_debugfs_status_operations = {
157	.owner		= THIS_MODULE,
158	.open		= coh901318_debugfs_open,
159	.read		= coh901318_debugfs_read,
160};
161
162
163static int __init init_coh901318_debugfs(void)
164{
165
166	dma_dentry = debugfs_create_dir("dma", NULL);
167
168	(void) debugfs_create_file("status",
169				   S_IFREG | S_IRUGO,
170				   dma_dentry, NULL,
171				   &coh901318_debugfs_status_operations);
172	return 0;
173}
174
175static void __exit exit_coh901318_debugfs(void)
176{
177	debugfs_remove_recursive(dma_dentry);
178}
179
180module_init(init_coh901318_debugfs);
181module_exit(exit_coh901318_debugfs);
182#else
183
184#define COH901318_DEBUGFS_ASSIGN(x, y)
185
186#endif /* CONFIG_DEBUG_FS */
187
188static inline struct coh901318_chan *to_coh901318_chan(struct dma_chan *chan)
189{
190	return container_of(chan, struct coh901318_chan, chan);
191}
192
193static inline dma_addr_t
194cohc_dev_addr(struct coh901318_chan *cohc)
195{
196	/* Runtime supplied address will take precedence */
197	if (cohc->runtime_addr)
198		return cohc->runtime_addr;
199	return cohc->base->platform->chan_conf[cohc->id].dev_addr;
200}
201
202static inline const struct coh901318_params *
203cohc_chan_param(struct coh901318_chan *cohc)
204{
205	return &cohc->base->platform->chan_conf[cohc->id].param;
206}
207
208static inline const struct coh_dma_channel *
209cohc_chan_conf(struct coh901318_chan *cohc)
210{
211	return &cohc->base->platform->chan_conf[cohc->id];
212}
213
214static void enable_powersave(struct coh901318_chan *cohc)
215{
216	unsigned long flags;
217	struct powersave *pm = &cohc->base->pm;
218
219	spin_lock_irqsave(&pm->lock, flags);
220
221	pm->started_channels &= ~(1ULL << cohc->id);
222
223	if (!pm->started_channels) {
224		/* DMA no longer intends to access memory */
225		cohc->base->platform->access_memory_state(cohc->base->dev,
226							  false);
227	}
228
229	spin_unlock_irqrestore(&pm->lock, flags);
230}
231static void disable_powersave(struct coh901318_chan *cohc)
232{
233	unsigned long flags;
234	struct powersave *pm = &cohc->base->pm;
235
236	spin_lock_irqsave(&pm->lock, flags);
237
238	if (!pm->started_channels) {
239		/* DMA intends to access memory */
240		cohc->base->platform->access_memory_state(cohc->base->dev,
241							  true);
242	}
243
244	pm->started_channels |= (1ULL << cohc->id);
245
246	spin_unlock_irqrestore(&pm->lock, flags);
247}
248
249static inline int coh901318_set_ctrl(struct coh901318_chan *cohc, u32 control)
250{
251	int channel = cohc->id;
252	void __iomem *virtbase = cohc->base->virtbase;
253
254	writel(control,
255	       virtbase + COH901318_CX_CTRL +
256	       COH901318_CX_CTRL_SPACING * channel);
257	return 0;
258}
259
260static inline int coh901318_set_conf(struct coh901318_chan *cohc, u32 conf)
261{
262	int channel = cohc->id;
263	void __iomem *virtbase = cohc->base->virtbase;
264
265	writel(conf,
266	       virtbase + COH901318_CX_CFG +
267	       COH901318_CX_CFG_SPACING*channel);
268	return 0;
269}
270
271
272static int coh901318_start(struct coh901318_chan *cohc)
273{
274	u32 val;
275	int channel = cohc->id;
276	void __iomem *virtbase = cohc->base->virtbase;
277
278	disable_powersave(cohc);
279
280	val = readl(virtbase + COH901318_CX_CFG +
281		    COH901318_CX_CFG_SPACING * channel);
282
283	/* Enable channel */
284	val |= COH901318_CX_CFG_CH_ENABLE;
285	writel(val, virtbase + COH901318_CX_CFG +
286	       COH901318_CX_CFG_SPACING * channel);
287
288	return 0;
289}
290
291static int coh901318_prep_linked_list(struct coh901318_chan *cohc,
292				      struct coh901318_lli *lli)
293{
294	int channel = cohc->id;
295	void __iomem *virtbase = cohc->base->virtbase;
296
297	BUG_ON(readl(virtbase + COH901318_CX_STAT +
298		     COH901318_CX_STAT_SPACING*channel) &
299	       COH901318_CX_STAT_ACTIVE);
300
301	writel(lli->src_addr,
302	       virtbase + COH901318_CX_SRC_ADDR +
303	       COH901318_CX_SRC_ADDR_SPACING * channel);
304
305	writel(lli->dst_addr, virtbase +
306	       COH901318_CX_DST_ADDR +
307	       COH901318_CX_DST_ADDR_SPACING * channel);
308
309	writel(lli->link_addr, virtbase + COH901318_CX_LNK_ADDR +
310	       COH901318_CX_LNK_ADDR_SPACING * channel);
311
312	writel(lli->control, virtbase + COH901318_CX_CTRL +
313	       COH901318_CX_CTRL_SPACING * channel);
314
315	return 0;
316}
317static dma_cookie_t
318coh901318_assign_cookie(struct coh901318_chan *cohc,
319			struct coh901318_desc *cohd)
320{
321	dma_cookie_t cookie = cohc->chan.cookie;
322
323	if (++cookie < 0)
324		cookie = 1;
325
326	cohc->chan.cookie = cookie;
327	cohd->desc.cookie = cookie;
328
329	return cookie;
330}
331
332static struct coh901318_desc *
333coh901318_desc_get(struct coh901318_chan *cohc)
334{
335	struct coh901318_desc *desc;
336
337	if (list_empty(&cohc->free)) {
338		/* alloc new desc because we're out of used ones
339		 * TODO: alloc a pile of descs instead of just one,
340		 * avoid many small allocations.
341		 */
342		desc = kzalloc(sizeof(struct coh901318_desc), GFP_NOWAIT);
343		if (desc == NULL)
344			goto out;
345		INIT_LIST_HEAD(&desc->node);
346		dma_async_tx_descriptor_init(&desc->desc, &cohc->chan);
347	} else {
348		/* Reuse an old desc. */
349		desc = list_first_entry(&cohc->free,
350					struct coh901318_desc,
351					node);
352		list_del(&desc->node);
353		/* Initialize it a bit so it's not insane */
354		desc->sg = NULL;
355		desc->sg_len = 0;
356		desc->desc.callback = NULL;
357		desc->desc.callback_param = NULL;
358	}
359
360 out:
361	return desc;
362}
363
364static void
365coh901318_desc_free(struct coh901318_chan *cohc, struct coh901318_desc *cohd)
366{
367	list_add_tail(&cohd->node, &cohc->free);
368}
369
370/* call with irq lock held */
371static void
372coh901318_desc_submit(struct coh901318_chan *cohc, struct coh901318_desc *desc)
373{
374	list_add_tail(&desc->node, &cohc->active);
375}
376
377static struct coh901318_desc *
378coh901318_first_active_get(struct coh901318_chan *cohc)
379{
380	struct coh901318_desc *d;
381
382	if (list_empty(&cohc->active))
383		return NULL;
384
385	d = list_first_entry(&cohc->active,
386			     struct coh901318_desc,
387			     node);
388	return d;
389}
390
391static void
392coh901318_desc_remove(struct coh901318_desc *cohd)
393{
394	list_del(&cohd->node);
395}
396
397static void
398coh901318_desc_queue(struct coh901318_chan *cohc, struct coh901318_desc *desc)
399{
400	list_add_tail(&desc->node, &cohc->queue);
401}
402
403static struct coh901318_desc *
404coh901318_first_queued(struct coh901318_chan *cohc)
405{
406	struct coh901318_desc *d;
407
408	if (list_empty(&cohc->queue))
409		return NULL;
410
411	d = list_first_entry(&cohc->queue,
412			     struct coh901318_desc,
413			     node);
414	return d;
415}
416
417static inline u32 coh901318_get_bytes_in_lli(struct coh901318_lli *in_lli)
418{
419	struct coh901318_lli *lli = in_lli;
420	u32 bytes = 0;
421
422	while (lli) {
423		bytes += lli->control & COH901318_CX_CTRL_TC_VALUE_MASK;
424		lli = lli->virt_link_addr;
425	}
426	return bytes;
427}
428
429/*
430 * Get the number of bytes left to transfer on this channel,
431 * it is unwise to call this before stopping the channel for
432 * absolute measures, but for a rough guess you can still call
433 * it.
434 */
435static u32 coh901318_get_bytes_left(struct dma_chan *chan)
436{
437	struct coh901318_chan *cohc = to_coh901318_chan(chan);
438	struct coh901318_desc *cohd;
439	struct list_head *pos;
440	unsigned long flags;
441	u32 left = 0;
442	int i = 0;
443
444	spin_lock_irqsave(&cohc->lock, flags);
445
446	/*
447	 * If there are many queued jobs, we iterate and add the
448	 * size of them all. We take a special look on the first
449	 * job though, since it is probably active.
450	 */
451	list_for_each(pos, &cohc->active) {
452		/*
453		 * The first job in the list will be working on the
454		 * hardware. The job can be stopped but still active,
455		 * so that the transfer counter is somewhere inside
456		 * the buffer.
457		 */
458		cohd = list_entry(pos, struct coh901318_desc, node);
459
460		if (i == 0) {
461			struct coh901318_lli *lli;
462			dma_addr_t ladd;
463
464			/* Read current transfer count value */
465			left = readl(cohc->base->virtbase +
466				     COH901318_CX_CTRL +
467				     COH901318_CX_CTRL_SPACING * cohc->id) &
468				COH901318_CX_CTRL_TC_VALUE_MASK;
469
470			/* See if the transfer is linked... */
471			ladd = readl(cohc->base->virtbase +
472				     COH901318_CX_LNK_ADDR +
473				     COH901318_CX_LNK_ADDR_SPACING *
474				     cohc->id) &
475				~COH901318_CX_LNK_LINK_IMMEDIATE;
476			/* Single transaction */
477			if (!ladd)
478				continue;
479
480			/*
481			 * Linked transaction, follow the lli, find the
482			 * currently processing lli, and proceed to the next
483			 */
484			lli = cohd->lli;
485			while (lli && lli->link_addr != ladd)
486				lli = lli->virt_link_addr;
487
488			if (lli)
489				lli = lli->virt_link_addr;
490
491			/*
492			 * Follow remaining lli links around to count the total
493			 * number of bytes left
494			 */
495			left += coh901318_get_bytes_in_lli(lli);
496		} else {
497			left += coh901318_get_bytes_in_lli(cohd->lli);
498		}
499		i++;
500	}
501
502	/* Also count bytes in the queued jobs */
503	list_for_each(pos, &cohc->queue) {
504		cohd = list_entry(pos, struct coh901318_desc, node);
505		left += coh901318_get_bytes_in_lli(cohd->lli);
506	}
507
508	spin_unlock_irqrestore(&cohc->lock, flags);
509
510	return left;
511}
512
513/*
514 * Pauses a transfer without losing data. Enables power save.
515 * Use this function in conjunction with coh901318_resume.
516 */
517static void coh901318_pause(struct dma_chan *chan)
518{
519	u32 val;
520	unsigned long flags;
521	struct coh901318_chan *cohc = to_coh901318_chan(chan);
522	int channel = cohc->id;
523	void __iomem *virtbase = cohc->base->virtbase;
524
525	spin_lock_irqsave(&cohc->lock, flags);
526
527	/* Disable channel in HW */
528	val = readl(virtbase + COH901318_CX_CFG +
529		    COH901318_CX_CFG_SPACING * channel);
530
531	/* Stopping infinit transfer */
532	if ((val & COH901318_CX_CTRL_TC_ENABLE) == 0 &&
533	    (val & COH901318_CX_CFG_CH_ENABLE))
534		cohc->stopped = 1;
535
536
537	val &= ~COH901318_CX_CFG_CH_ENABLE;
538	writel(val, virtbase + COH901318_CX_CFG +
539	       COH901318_CX_CFG_SPACING * channel);
540	writel(val, virtbase + COH901318_CX_CFG +
541	       COH901318_CX_CFG_SPACING * channel);
542
543	/* Spin-wait for it to actually go inactive */
544	while (readl(virtbase + COH901318_CX_STAT+COH901318_CX_STAT_SPACING *
545		     channel) & COH901318_CX_STAT_ACTIVE)
546		cpu_relax();
547
548	/* Check if we stopped an active job */
549	if ((readl(virtbase + COH901318_CX_CTRL+COH901318_CX_CTRL_SPACING *
550		   channel) & COH901318_CX_CTRL_TC_VALUE_MASK) > 0)
551		cohc->stopped = 1;
552
553	enable_powersave(cohc);
554
555	spin_unlock_irqrestore(&cohc->lock, flags);
556}
557
558/* Resumes a transfer that has been stopped via 300_dma_stop(..).
559   Power save is handled.
560*/
561static void coh901318_resume(struct dma_chan *chan)
562{
563	u32 val;
564	unsigned long flags;
565	struct coh901318_chan *cohc = to_coh901318_chan(chan);
566	int channel = cohc->id;
567
568	spin_lock_irqsave(&cohc->lock, flags);
569
570	disable_powersave(cohc);
571
572	if (cohc->stopped) {
573		/* Enable channel in HW */
574		val = readl(cohc->base->virtbase + COH901318_CX_CFG +
575			    COH901318_CX_CFG_SPACING * channel);
576
577		val |= COH901318_CX_CFG_CH_ENABLE;
578
579		writel(val, cohc->base->virtbase + COH901318_CX_CFG +
580		       COH901318_CX_CFG_SPACING*channel);
581
582		cohc->stopped = 0;
583	}
584
585	spin_unlock_irqrestore(&cohc->lock, flags);
586}
587
588bool coh901318_filter_id(struct dma_chan *chan, void *chan_id)
589{
590	unsigned int ch_nr = (unsigned int) chan_id;
591
592	if (ch_nr == to_coh901318_chan(chan)->id)
593		return true;
594
595	return false;
596}
597EXPORT_SYMBOL(coh901318_filter_id);
598
599/*
600 * DMA channel allocation
601 */
602static int coh901318_config(struct coh901318_chan *cohc,
603			    struct coh901318_params *param)
604{
605	unsigned long flags;
606	const struct coh901318_params *p;
607	int channel = cohc->id;
608	void __iomem *virtbase = cohc->base->virtbase;
609
610	spin_lock_irqsave(&cohc->lock, flags);
611
612	if (param)
613		p = param;
614	else
615		p = &cohc->base->platform->chan_conf[channel].param;
616
617	/* Clear any pending BE or TC interrupt */
618	if (channel < 32) {
619		writel(1 << channel, virtbase + COH901318_BE_INT_CLEAR1);
620		writel(1 << channel, virtbase + COH901318_TC_INT_CLEAR1);
621	} else {
622		writel(1 << (channel - 32), virtbase +
623		       COH901318_BE_INT_CLEAR2);
624		writel(1 << (channel - 32), virtbase +
625		       COH901318_TC_INT_CLEAR2);
626	}
627
628	coh901318_set_conf(cohc, p->config);
629	coh901318_set_ctrl(cohc, p->ctrl_lli_last);
630
631	spin_unlock_irqrestore(&cohc->lock, flags);
632
633	return 0;
634}
635
636/* must lock when calling this function
637 * start queued jobs, if any
638 * TODO: start all queued jobs in one go
639 *
640 * Returns descriptor if queued job is started otherwise NULL.
641 * If the queue is empty NULL is returned.
642 */
643static struct coh901318_desc *coh901318_queue_start(struct coh901318_chan *cohc)
644{
645	struct coh901318_desc *cohd;
646
647	/*
648	 * start queued jobs, if any
649	 * TODO: transmit all queued jobs in one go
650	 */
651	cohd = coh901318_first_queued(cohc);
652
653	if (cohd != NULL) {
654		/* Remove from queue */
655		coh901318_desc_remove(cohd);
656		/* initiate DMA job */
657		cohc->busy = 1;
658
659		coh901318_desc_submit(cohc, cohd);
660
661		coh901318_prep_linked_list(cohc, cohd->lli);
662
663		/* start dma job on this channel */
664		coh901318_start(cohc);
665
666	}
667
668	return cohd;
669}
670
671/*
672 * This tasklet is called from the interrupt handler to
673 * handle each descriptor (DMA job) that is sent to a channel.
674 */
675static void dma_tasklet(unsigned long data)
676{
677	struct coh901318_chan *cohc = (struct coh901318_chan *) data;
678	struct coh901318_desc *cohd_fin;
679	unsigned long flags;
680	dma_async_tx_callback callback;
681	void *callback_param;
682
683	dev_vdbg(COHC_2_DEV(cohc), "[%s] chan_id %d"
684		 " nbr_active_done %ld\n", __func__,
685		 cohc->id, cohc->nbr_active_done);
686
687	spin_lock_irqsave(&cohc->lock, flags);
688
689	/* get first active descriptor entry from list */
690	cohd_fin = coh901318_first_active_get(cohc);
691
692	if (cohd_fin == NULL)
693		goto err;
694
695	/* locate callback to client */
696	callback = cohd_fin->desc.callback;
697	callback_param = cohd_fin->desc.callback_param;
698
699	/* sign this job as completed on the channel */
700	cohc->completed = cohd_fin->desc.cookie;
701
702	/* release the lli allocation and remove the descriptor */
703	coh901318_lli_free(&cohc->base->pool, &cohd_fin->lli);
704
705	/* return desc to free-list */
706	coh901318_desc_remove(cohd_fin);
707	coh901318_desc_free(cohc, cohd_fin);
708
709	spin_unlock_irqrestore(&cohc->lock, flags);
710
711	/* Call the callback when we're done */
712	if (callback)
713		callback(callback_param);
714
715	spin_lock_irqsave(&cohc->lock, flags);
716
717	/*
718	 * If another interrupt fired while the tasklet was scheduling,
719	 * we don't get called twice, so we have this number of active
720	 * counter that keep track of the number of IRQs expected to
721	 * be handled for this channel. If there happen to be more than
722	 * one IRQ to be ack:ed, we simply schedule this tasklet again.
723	 */
724	cohc->nbr_active_done--;
725	if (cohc->nbr_active_done) {
726		dev_dbg(COHC_2_DEV(cohc), "scheduling tasklet again, new IRQs "
727			"came in while we were scheduling this tasklet\n");
728		if (cohc_chan_conf(cohc)->priority_high)
729			tasklet_hi_schedule(&cohc->tasklet);
730		else
731			tasklet_schedule(&cohc->tasklet);
732	}
733
734	spin_unlock_irqrestore(&cohc->lock, flags);
735
736	return;
737
738 err:
739	spin_unlock_irqrestore(&cohc->lock, flags);
740	dev_err(COHC_2_DEV(cohc), "[%s] No active dma desc\n", __func__);
741}
742
743
744/* called from interrupt context */
745static void dma_tc_handle(struct coh901318_chan *cohc)
746{
747	/*
748	 * If the channel is not allocated, then we shouldn't have
749	 * any TC interrupts on it.
750	 */
751	if (!cohc->allocated) {
752		dev_err(COHC_2_DEV(cohc), "spurious interrupt from "
753			"unallocated channel\n");
754		return;
755	}
756
757	spin_lock(&cohc->lock);
758
759	/*
760	 * When we reach this point, at least one queue item
761	 * should have been moved over from cohc->queue to
762	 * cohc->active and run to completion, that is why we're
763	 * getting a terminal count interrupt is it not?
764	 * If you get this BUG() the most probable cause is that
765	 * the individual nodes in the lli chain have IRQ enabled,
766	 * so check your platform config for lli chain ctrl.
767	 */
768	BUG_ON(list_empty(&cohc->active));
769
770	cohc->nbr_active_done++;
771
772	/*
773	 * This attempt to take a job from cohc->queue, put it
774	 * into cohc->active and start it.
775	 */
776	if (coh901318_queue_start(cohc) == NULL)
777		cohc->busy = 0;
778
779	spin_unlock(&cohc->lock);
780
781	/*
782	 * This tasklet will remove items from cohc->active
783	 * and thus terminates them.
784	 */
785	if (cohc_chan_conf(cohc)->priority_high)
786		tasklet_hi_schedule(&cohc->tasklet);
787	else
788		tasklet_schedule(&cohc->tasklet);
789}
790
791
792static irqreturn_t dma_irq_handler(int irq, void *dev_id)
793{
794	u32 status1;
795	u32 status2;
796	int i;
797	int ch;
798	struct coh901318_base *base  = dev_id;
799	struct coh901318_chan *cohc;
800	void __iomem *virtbase = base->virtbase;
801
802	status1 = readl(virtbase + COH901318_INT_STATUS1);
803	status2 = readl(virtbase + COH901318_INT_STATUS2);
804
805	if (unlikely(status1 == 0 && status2 == 0)) {
806		dev_warn(base->dev, "spurious DMA IRQ from no channel!\n");
807		return IRQ_HANDLED;
808	}
809
810	/* TODO: consider handle IRQ in tasklet here to
811	 *       minimize interrupt latency */
812
813	/* Check the first 32 DMA channels for IRQ */
814	while (status1) {
815		/* Find first bit set, return as a number. */
816		i = ffs(status1) - 1;
817		ch = i;
818
819		cohc = &base->chans[ch];
820		spin_lock(&cohc->lock);
821
822		/* Mask off this bit */
823		status1 &= ~(1 << i);
824		/* Check the individual channel bits */
825		if (test_bit(i, virtbase + COH901318_BE_INT_STATUS1)) {
826			dev_crit(COHC_2_DEV(cohc),
827				 "DMA bus error on channel %d!\n", ch);
828			BUG_ON(1);
829			/* Clear BE interrupt */
830			__set_bit(i, virtbase + COH901318_BE_INT_CLEAR1);
831		} else {
832			/* Caused by TC, really? */
833			if (unlikely(!test_bit(i, virtbase +
834					       COH901318_TC_INT_STATUS1))) {
835				dev_warn(COHC_2_DEV(cohc),
836					 "ignoring interrupt not caused by terminal count on channel %d\n", ch);
837				/* Clear TC interrupt */
838				BUG_ON(1);
839				__set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
840			} else {
841				/* Enable powersave if transfer has finished */
842				if (!(readl(virtbase + COH901318_CX_STAT +
843					    COH901318_CX_STAT_SPACING*ch) &
844				      COH901318_CX_STAT_ENABLED)) {
845					enable_powersave(cohc);
846				}
847
848				/* Must clear TC interrupt before calling
849				 * dma_tc_handle
850				 * in case tc_handle initate a new dma job
851				 */
852				__set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
853
854				dma_tc_handle(cohc);
855			}
856		}
857		spin_unlock(&cohc->lock);
858	}
859
860	/* Check the remaining 32 DMA channels for IRQ */
861	while (status2) {
862		/* Find first bit set, return as a number. */
863		i = ffs(status2) - 1;
864		ch = i + 32;
865		cohc = &base->chans[ch];
866		spin_lock(&cohc->lock);
867
868		/* Mask off this bit */
869		status2 &= ~(1 << i);
870		/* Check the individual channel bits */
871		if (test_bit(i, virtbase + COH901318_BE_INT_STATUS2)) {
872			dev_crit(COHC_2_DEV(cohc),
873				 "DMA bus error on channel %d!\n", ch);
874			/* Clear BE interrupt */
875			BUG_ON(1);
876			__set_bit(i, virtbase + COH901318_BE_INT_CLEAR2);
877		} else {
878			/* Caused by TC, really? */
879			if (unlikely(!test_bit(i, virtbase +
880					       COH901318_TC_INT_STATUS2))) {
881				dev_warn(COHC_2_DEV(cohc),
882					 "ignoring interrupt not caused by terminal count on channel %d\n", ch);
883				/* Clear TC interrupt */
884				__set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
885				BUG_ON(1);
886			} else {
887				/* Enable powersave if transfer has finished */
888				if (!(readl(virtbase + COH901318_CX_STAT +
889					    COH901318_CX_STAT_SPACING*ch) &
890				      COH901318_CX_STAT_ENABLED)) {
891					enable_powersave(cohc);
892				}
893				/* Must clear TC interrupt before calling
894				 * dma_tc_handle
895				 * in case tc_handle initate a new dma job
896				 */
897				__set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
898
899				dma_tc_handle(cohc);
900			}
901		}
902		spin_unlock(&cohc->lock);
903	}
904
905	return IRQ_HANDLED;
906}
907
908static int coh901318_alloc_chan_resources(struct dma_chan *chan)
909{
910	struct coh901318_chan	*cohc = to_coh901318_chan(chan);
911	unsigned long flags;
912
913	dev_vdbg(COHC_2_DEV(cohc), "[%s] DMA channel %d\n",
914		 __func__, cohc->id);
915
916	if (chan->client_count > 1)
917		return -EBUSY;
918
919	spin_lock_irqsave(&cohc->lock, flags);
920
921	coh901318_config(cohc, NULL);
922
923	cohc->allocated = 1;
924	cohc->completed = chan->cookie = 1;
925
926	spin_unlock_irqrestore(&cohc->lock, flags);
927
928	return 1;
929}
930
931static void
932coh901318_free_chan_resources(struct dma_chan *chan)
933{
934	struct coh901318_chan	*cohc = to_coh901318_chan(chan);
935	int channel = cohc->id;
936	unsigned long flags;
937
938	spin_lock_irqsave(&cohc->lock, flags);
939
940	/* Disable HW */
941	writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CFG +
942	       COH901318_CX_CFG_SPACING*channel);
943	writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CTRL +
944	       COH901318_CX_CTRL_SPACING*channel);
945
946	cohc->allocated = 0;
947
948	spin_unlock_irqrestore(&cohc->lock, flags);
949
950	chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
951}
952
953
954static dma_cookie_t
955coh901318_tx_submit(struct dma_async_tx_descriptor *tx)
956{
957	struct coh901318_desc *cohd = container_of(tx, struct coh901318_desc,
958						   desc);
959	struct coh901318_chan *cohc = to_coh901318_chan(tx->chan);
960	unsigned long flags;
961
962	spin_lock_irqsave(&cohc->lock, flags);
963
964	tx->cookie = coh901318_assign_cookie(cohc, cohd);
965
966	coh901318_desc_queue(cohc, cohd);
967
968	spin_unlock_irqrestore(&cohc->lock, flags);
969
970	return tx->cookie;
971}
972
973static struct dma_async_tx_descriptor *
974coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
975		      size_t size, unsigned long flags)
976{
977	struct coh901318_lli *lli;
978	struct coh901318_desc *cohd;
979	unsigned long flg;
980	struct coh901318_chan *cohc = to_coh901318_chan(chan);
981	int lli_len;
982	u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
983	int ret;
984
985	spin_lock_irqsave(&cohc->lock, flg);
986
987	dev_vdbg(COHC_2_DEV(cohc),
988		 "[%s] channel %d src 0x%x dest 0x%x size %d\n",
989		 __func__, cohc->id, src, dest, size);
990
991	if (flags & DMA_PREP_INTERRUPT)
992		/* Trigger interrupt after last lli */
993		ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
994
995	lli_len = size >> MAX_DMA_PACKET_SIZE_SHIFT;
996	if ((lli_len << MAX_DMA_PACKET_SIZE_SHIFT) < size)
997		lli_len++;
998
999	lli = coh901318_lli_alloc(&cohc->base->pool, lli_len);
1000
1001	if (lli == NULL)
1002		goto err;
1003
1004	ret = coh901318_lli_fill_memcpy(
1005		&cohc->base->pool, lli, src, size, dest,
1006		cohc_chan_param(cohc)->ctrl_lli_chained,
1007		ctrl_last);
1008	if (ret)
1009		goto err;
1010
1011	COH_DBG(coh901318_list_print(cohc, lli));
1012
1013	/* Pick a descriptor to handle this transfer */
1014	cohd = coh901318_desc_get(cohc);
1015	cohd->lli = lli;
1016	cohd->flags = flags;
1017	cohd->desc.tx_submit = coh901318_tx_submit;
1018
1019	spin_unlock_irqrestore(&cohc->lock, flg);
1020
1021	return &cohd->desc;
1022 err:
1023	spin_unlock_irqrestore(&cohc->lock, flg);
1024	return NULL;
1025}
1026
1027static struct dma_async_tx_descriptor *
1028coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
1029			unsigned int sg_len, enum dma_data_direction direction,
1030			unsigned long flags)
1031{
1032	struct coh901318_chan *cohc = to_coh901318_chan(chan);
1033	struct coh901318_lli *lli;
1034	struct coh901318_desc *cohd;
1035	const struct coh901318_params *params;
1036	struct scatterlist *sg;
1037	int len = 0;
1038	int size;
1039	int i;
1040	u32 ctrl_chained = cohc_chan_param(cohc)->ctrl_lli_chained;
1041	u32 ctrl = cohc_chan_param(cohc)->ctrl_lli;
1042	u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
1043	u32 config;
1044	unsigned long flg;
1045	int ret;
1046
1047	if (!sgl)
1048		goto out;
1049	if (sgl->length == 0)
1050		goto out;
1051
1052	spin_lock_irqsave(&cohc->lock, flg);
1053
1054	dev_vdbg(COHC_2_DEV(cohc), "[%s] sg_len %d dir %d\n",
1055		 __func__, sg_len, direction);
1056
1057	if (flags & DMA_PREP_INTERRUPT)
1058		/* Trigger interrupt after last lli */
1059		ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
1060
1061	params = cohc_chan_param(cohc);
1062	config = params->config;
1063	/*
1064	 * Add runtime-specific control on top, make
1065	 * sure the bits you set per peripheral channel are
1066	 * cleared in the default config from the platform.
1067	 */
1068	ctrl_chained |= cohc->runtime_ctrl;
1069	ctrl_last |= cohc->runtime_ctrl;
1070	ctrl |= cohc->runtime_ctrl;
1071
1072	if (direction == DMA_TO_DEVICE) {
1073		u32 tx_flags = COH901318_CX_CTRL_PRDD_SOURCE |
1074			COH901318_CX_CTRL_SRC_ADDR_INC_ENABLE;
1075
1076		config |= COH901318_CX_CFG_RM_MEMORY_TO_PRIMARY;
1077		ctrl_chained |= tx_flags;
1078		ctrl_last |= tx_flags;
1079		ctrl |= tx_flags;
1080	} else if (direction == DMA_FROM_DEVICE) {
1081		u32 rx_flags = COH901318_CX_CTRL_PRDD_DEST |
1082			COH901318_CX_CTRL_DST_ADDR_INC_ENABLE;
1083
1084		config |= COH901318_CX_CFG_RM_PRIMARY_TO_MEMORY;
1085		ctrl_chained |= rx_flags;
1086		ctrl_last |= rx_flags;
1087		ctrl |= rx_flags;
1088	} else
1089		goto err_direction;
1090
1091	coh901318_set_conf(cohc, config);
1092
1093	/* The dma only supports transmitting packages up to
1094	 * MAX_DMA_PACKET_SIZE. Calculate to total number of
1095	 * dma elemts required to send the entire sg list
1096	 */
1097	for_each_sg(sgl, sg, sg_len, i) {
1098		unsigned int factor;
1099		size = sg_dma_len(sg);
1100
1101		if (size <= MAX_DMA_PACKET_SIZE) {
1102			len++;
1103			continue;
1104		}
1105
1106		factor = size >> MAX_DMA_PACKET_SIZE_SHIFT;
1107		if ((factor << MAX_DMA_PACKET_SIZE_SHIFT) < size)
1108			factor++;
1109
1110		len += factor;
1111	}
1112
1113	pr_debug("Allocate %d lli:s for this transfer\n", len);
1114	lli = coh901318_lli_alloc(&cohc->base->pool, len);
1115
1116	if (lli == NULL)
1117		goto err_dma_alloc;
1118
1119	/* initiate allocated lli list */
1120	ret = coh901318_lli_fill_sg(&cohc->base->pool, lli, sgl, sg_len,
1121				    cohc_dev_addr(cohc),
1122				    ctrl_chained,
1123				    ctrl,
1124				    ctrl_last,
1125				    direction, COH901318_CX_CTRL_TC_IRQ_ENABLE);
1126	if (ret)
1127		goto err_lli_fill;
1128
1129	/*
1130	 * Set the default ctrl for the channel to the one from the lli,
1131	 * things may have changed due to odd buffer alignment etc.
1132	 */
1133	coh901318_set_ctrl(cohc, lli->control);
1134
1135	COH_DBG(coh901318_list_print(cohc, lli));
1136
1137	/* Pick a descriptor to handle this transfer */
1138	cohd = coh901318_desc_get(cohc);
1139	cohd->dir = direction;
1140	cohd->flags = flags;
1141	cohd->desc.tx_submit = coh901318_tx_submit;
1142	cohd->lli = lli;
1143
1144	spin_unlock_irqrestore(&cohc->lock, flg);
1145
1146	return &cohd->desc;
1147 err_lli_fill:
1148 err_dma_alloc:
1149 err_direction:
1150	spin_unlock_irqrestore(&cohc->lock, flg);
1151 out:
1152	return NULL;
1153}
1154
1155static enum dma_status
1156coh901318_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1157		 struct dma_tx_state *txstate)
1158{
1159	struct coh901318_chan *cohc = to_coh901318_chan(chan);
1160	dma_cookie_t last_used;
1161	dma_cookie_t last_complete;
1162	int ret;
1163
1164	last_complete = cohc->completed;
1165	last_used = chan->cookie;
1166
1167	ret = dma_async_is_complete(cookie, last_complete, last_used);
1168
1169	dma_set_tx_state(txstate, last_complete, last_used,
1170			 coh901318_get_bytes_left(chan));
1171	if (ret == DMA_IN_PROGRESS && cohc->stopped)
1172		ret = DMA_PAUSED;
1173
1174	return ret;
1175}
1176
1177static void
1178coh901318_issue_pending(struct dma_chan *chan)
1179{
1180	struct coh901318_chan *cohc = to_coh901318_chan(chan);
1181	unsigned long flags;
1182
1183	spin_lock_irqsave(&cohc->lock, flags);
1184
1185	/*
1186	 * Busy means that pending jobs are already being processed,
1187	 * and then there is no point in starting the queue: the
1188	 * terminal count interrupt on the channel will take the next
1189	 * job on the queue and execute it anyway.
1190	 */
1191	if (!cohc->busy)
1192		coh901318_queue_start(cohc);
1193
1194	spin_unlock_irqrestore(&cohc->lock, flags);
1195}
1196
1197/*
1198 * Here we wrap in the runtime dma control interface
1199 */
1200struct burst_table {
1201	int burst_8bit;
1202	int burst_16bit;
1203	int burst_32bit;
1204	u32 reg;
1205};
1206
1207static const struct burst_table burst_sizes[] = {
1208	{
1209		.burst_8bit = 64,
1210		.burst_16bit = 32,
1211		.burst_32bit = 16,
1212		.reg = COH901318_CX_CTRL_BURST_COUNT_64_BYTES,
1213	},
1214	{
1215		.burst_8bit = 48,
1216		.burst_16bit = 24,
1217		.burst_32bit = 12,
1218		.reg = COH901318_CX_CTRL_BURST_COUNT_48_BYTES,
1219	},
1220	{
1221		.burst_8bit = 32,
1222		.burst_16bit = 16,
1223		.burst_32bit = 8,
1224		.reg = COH901318_CX_CTRL_BURST_COUNT_32_BYTES,
1225	},
1226	{
1227		.burst_8bit = 16,
1228		.burst_16bit = 8,
1229		.burst_32bit = 4,
1230		.reg = COH901318_CX_CTRL_BURST_COUNT_16_BYTES,
1231	},
1232	{
1233		.burst_8bit = 8,
1234		.burst_16bit = 4,
1235		.burst_32bit = 2,
1236		.reg = COH901318_CX_CTRL_BURST_COUNT_8_BYTES,
1237	},
1238	{
1239		.burst_8bit = 4,
1240		.burst_16bit = 2,
1241		.burst_32bit = 1,
1242		.reg = COH901318_CX_CTRL_BURST_COUNT_4_BYTES,
1243	},
1244	{
1245		.burst_8bit = 2,
1246		.burst_16bit = 1,
1247		.burst_32bit = 0,
1248		.reg = COH901318_CX_CTRL_BURST_COUNT_2_BYTES,
1249	},
1250	{
1251		.burst_8bit = 1,
1252		.burst_16bit = 0,
1253		.burst_32bit = 0,
1254		.reg = COH901318_CX_CTRL_BURST_COUNT_1_BYTE,
1255	},
1256};
1257
1258static void coh901318_dma_set_runtimeconfig(struct dma_chan *chan,
1259			struct dma_slave_config *config)
1260{
1261	struct coh901318_chan *cohc = to_coh901318_chan(chan);
1262	dma_addr_t addr;
1263	enum dma_slave_buswidth addr_width;
1264	u32 maxburst;
1265	u32 runtime_ctrl = 0;
1266	int i = 0;
1267
1268	/* We only support mem to per or per to mem transfers */
1269	if (config->direction == DMA_FROM_DEVICE) {
1270		addr = config->src_addr;
1271		addr_width = config->src_addr_width;
1272		maxburst = config->src_maxburst;
1273	} else if (config->direction == DMA_TO_DEVICE) {
1274		addr = config->dst_addr;
1275		addr_width = config->dst_addr_width;
1276		maxburst = config->dst_maxburst;
1277	} else {
1278		dev_err(COHC_2_DEV(cohc), "illegal channel mode\n");
1279		return;
1280	}
1281
1282	dev_dbg(COHC_2_DEV(cohc), "configure channel for %d byte transfers\n",
1283		addr_width);
1284	switch (addr_width)  {
1285	case DMA_SLAVE_BUSWIDTH_1_BYTE:
1286		runtime_ctrl |=
1287			COH901318_CX_CTRL_SRC_BUS_SIZE_8_BITS |
1288			COH901318_CX_CTRL_DST_BUS_SIZE_8_BITS;
1289
1290		while (i < ARRAY_SIZE(burst_sizes)) {
1291			if (burst_sizes[i].burst_8bit <= maxburst)
1292				break;
1293			i++;
1294		}
1295
1296		break;
1297	case DMA_SLAVE_BUSWIDTH_2_BYTES:
1298		runtime_ctrl |=
1299			COH901318_CX_CTRL_SRC_BUS_SIZE_16_BITS |
1300			COH901318_CX_CTRL_DST_BUS_SIZE_16_BITS;
1301
1302		while (i < ARRAY_SIZE(burst_sizes)) {
1303			if (burst_sizes[i].burst_16bit <= maxburst)
1304				break;
1305			i++;
1306		}
1307
1308		break;
1309	case DMA_SLAVE_BUSWIDTH_4_BYTES:
1310		/* Direction doesn't matter here, it's 32/32 bits */
1311		runtime_ctrl |=
1312			COH901318_CX_CTRL_SRC_BUS_SIZE_32_BITS |
1313			COH901318_CX_CTRL_DST_BUS_SIZE_32_BITS;
1314
1315		while (i < ARRAY_SIZE(burst_sizes)) {
1316			if (burst_sizes[i].burst_32bit <= maxburst)
1317				break;
1318			i++;
1319		}
1320
1321		break;
1322	default:
1323		dev_err(COHC_2_DEV(cohc),
1324			"bad runtimeconfig: alien address width\n");
1325		return;
1326	}
1327
1328	runtime_ctrl |= burst_sizes[i].reg;
1329	dev_dbg(COHC_2_DEV(cohc),
1330		"selected burst size %d bytes for address width %d bytes, maxburst %d\n",
1331		burst_sizes[i].burst_8bit, addr_width, maxburst);
1332
1333	cohc->runtime_addr = addr;
1334	cohc->runtime_ctrl = runtime_ctrl;
1335}
1336
1337static int
1338coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
1339		  unsigned long arg)
1340{
1341	unsigned long flags;
1342	struct coh901318_chan *cohc = to_coh901318_chan(chan);
1343	struct coh901318_desc *cohd;
1344	void __iomem *virtbase = cohc->base->virtbase;
1345
1346	if (cmd == DMA_SLAVE_CONFIG) {
1347		struct dma_slave_config *config =
1348			(struct dma_slave_config *) arg;
1349
1350		coh901318_dma_set_runtimeconfig(chan, config);
1351		return 0;
1352	  }
1353
1354	if (cmd == DMA_PAUSE) {
1355		coh901318_pause(chan);
1356		return 0;
1357	}
1358
1359	if (cmd == DMA_RESUME) {
1360		coh901318_resume(chan);
1361		return 0;
1362	}
1363
1364	if (cmd != DMA_TERMINATE_ALL)
1365		return -ENXIO;
1366
1367	/* The remainder of this function terminates the transfer */
1368	coh901318_pause(chan);
1369	spin_lock_irqsave(&cohc->lock, flags);
1370
1371	/* Clear any pending BE or TC interrupt */
1372	if (cohc->id < 32) {
1373		writel(1 << cohc->id, virtbase + COH901318_BE_INT_CLEAR1);
1374		writel(1 << cohc->id, virtbase + COH901318_TC_INT_CLEAR1);
1375	} else {
1376		writel(1 << (cohc->id - 32), virtbase +
1377		       COH901318_BE_INT_CLEAR2);
1378		writel(1 << (cohc->id - 32), virtbase +
1379		       COH901318_TC_INT_CLEAR2);
1380	}
1381
1382	enable_powersave(cohc);
1383
1384	while ((cohd = coh901318_first_active_get(cohc))) {
1385		/* release the lli allocation*/
1386		coh901318_lli_free(&cohc->base->pool, &cohd->lli);
1387
1388		/* return desc to free-list */
1389		coh901318_desc_remove(cohd);
1390		coh901318_desc_free(cohc, cohd);
1391	}
1392
1393	while ((cohd = coh901318_first_queued(cohc))) {
1394		/* release the lli allocation*/
1395		coh901318_lli_free(&cohc->base->pool, &cohd->lli);
1396
1397		/* return desc to free-list */
1398		coh901318_desc_remove(cohd);
1399		coh901318_desc_free(cohc, cohd);
1400	}
1401
1402
1403	cohc->nbr_active_done = 0;
1404	cohc->busy = 0;
1405
1406	spin_unlock_irqrestore(&cohc->lock, flags);
1407
1408	return 0;
1409}
1410
1411void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
1412			 struct coh901318_base *base)
1413{
1414	int chans_i;
1415	int i = 0;
1416	struct coh901318_chan *cohc;
1417
1418	INIT_LIST_HEAD(&dma->channels);
1419
1420	for (chans_i = 0; pick_chans[chans_i] != -1; chans_i += 2) {
1421		for (i = pick_chans[chans_i]; i <= pick_chans[chans_i+1]; i++) {
1422			cohc = &base->chans[i];
1423
1424			cohc->base = base;
1425			cohc->chan.device = dma;
1426			cohc->id = i;
1427
1428			/* TODO: do we really need this lock if only one
1429			 * client is connected to each channel?
1430			 */
1431
1432			spin_lock_init(&cohc->lock);
1433
1434			cohc->nbr_active_done = 0;
1435			cohc->busy = 0;
1436			INIT_LIST_HEAD(&cohc->free);
1437			INIT_LIST_HEAD(&cohc->active);
1438			INIT_LIST_HEAD(&cohc->queue);
1439
1440			tasklet_init(&cohc->tasklet, dma_tasklet,
1441				     (unsigned long) cohc);
1442
1443			list_add_tail(&cohc->chan.device_node,
1444				      &dma->channels);
1445		}
1446	}
1447}
1448
1449static int __init coh901318_probe(struct platform_device *pdev)
1450{
1451	int err = 0;
1452	struct coh901318_platform *pdata;
1453	struct coh901318_base *base;
1454	int irq;
1455	struct resource *io;
1456
1457	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1458	if (!io)
1459		goto err_get_resource;
1460
1461	/* Map DMA controller registers to virtual memory */
1462	if (request_mem_region(io->start,
1463			       resource_size(io),
1464			       pdev->dev.driver->name) == NULL) {
1465		err = -EBUSY;
1466		goto err_request_mem;
1467	}
1468
1469	pdata = pdev->dev.platform_data;
1470	if (!pdata)
1471		goto err_no_platformdata;
1472
1473	base = kmalloc(ALIGN(sizeof(struct coh901318_base), 4) +
1474		       pdata->max_channels *
1475		       sizeof(struct coh901318_chan),
1476		       GFP_KERNEL);
1477	if (!base)
1478		goto err_alloc_coh_dma_channels;
1479
1480	base->chans = ((void *)base) + ALIGN(sizeof(struct coh901318_base), 4);
1481
1482	base->virtbase = ioremap(io->start, resource_size(io));
1483	if (!base->virtbase) {
1484		err = -ENOMEM;
1485		goto err_no_ioremap;
1486	}
1487
1488	base->dev = &pdev->dev;
1489	base->platform = pdata;
1490	spin_lock_init(&base->pm.lock);
1491	base->pm.started_channels = 0;
1492
1493	COH901318_DEBUGFS_ASSIGN(debugfs_dma_base, base);
1494
1495	platform_set_drvdata(pdev, base);
1496
1497	irq = platform_get_irq(pdev, 0);
1498	if (irq < 0)
1499		goto err_no_irq;
1500
1501	err = request_irq(irq, dma_irq_handler, IRQF_DISABLED,
1502			  "coh901318", base);
1503	if (err) {
1504		dev_crit(&pdev->dev,
1505			 "Cannot allocate IRQ for DMA controller!\n");
1506		goto err_request_irq;
1507	}
1508
1509	err = coh901318_pool_create(&base->pool, &pdev->dev,
1510				    sizeof(struct coh901318_lli),
1511				    32);
1512	if (err)
1513		goto err_pool_create;
1514
1515	/* init channels for device transfers */
1516	coh901318_base_init(&base->dma_slave,  base->platform->chans_slave,
1517			    base);
1518
1519	dma_cap_zero(base->dma_slave.cap_mask);
1520	dma_cap_set(DMA_SLAVE, base->dma_slave.cap_mask);
1521
1522	base->dma_slave.device_alloc_chan_resources = coh901318_alloc_chan_resources;
1523	base->dma_slave.device_free_chan_resources = coh901318_free_chan_resources;
1524	base->dma_slave.device_prep_slave_sg = coh901318_prep_slave_sg;
1525	base->dma_slave.device_tx_status = coh901318_tx_status;
1526	base->dma_slave.device_issue_pending = coh901318_issue_pending;
1527	base->dma_slave.device_control = coh901318_control;
1528	base->dma_slave.dev = &pdev->dev;
1529
1530	err = dma_async_device_register(&base->dma_slave);
1531
1532	if (err)
1533		goto err_register_slave;
1534
1535	/* init channels for memcpy */
1536	coh901318_base_init(&base->dma_memcpy, base->platform->chans_memcpy,
1537			    base);
1538
1539	dma_cap_zero(base->dma_memcpy.cap_mask);
1540	dma_cap_set(DMA_MEMCPY, base->dma_memcpy.cap_mask);
1541
1542	base->dma_memcpy.device_alloc_chan_resources = coh901318_alloc_chan_resources;
1543	base->dma_memcpy.device_free_chan_resources = coh901318_free_chan_resources;
1544	base->dma_memcpy.device_prep_dma_memcpy = coh901318_prep_memcpy;
1545	base->dma_memcpy.device_tx_status = coh901318_tx_status;
1546	base->dma_memcpy.device_issue_pending = coh901318_issue_pending;
1547	base->dma_memcpy.device_control = coh901318_control;
1548	base->dma_memcpy.dev = &pdev->dev;
1549	/*
1550	 * This controller can only access address at even 32bit boundaries,
1551	 * i.e. 2^2
1552	 */
1553	base->dma_memcpy.copy_align = 2;
1554	err = dma_async_device_register(&base->dma_memcpy);
1555
1556	if (err)
1557		goto err_register_memcpy;
1558
1559	dev_info(&pdev->dev, "Initialized COH901318 DMA on virtual base 0x%08x\n",
1560		(u32) base->virtbase);
1561
1562	return err;
1563
1564 err_register_memcpy:
1565	dma_async_device_unregister(&base->dma_slave);
1566 err_register_slave:
1567	coh901318_pool_destroy(&base->pool);
1568 err_pool_create:
1569	free_irq(platform_get_irq(pdev, 0), base);
1570 err_request_irq:
1571 err_no_irq:
1572	iounmap(base->virtbase);
1573 err_no_ioremap:
1574	kfree(base);
1575 err_alloc_coh_dma_channels:
1576 err_no_platformdata:
1577	release_mem_region(pdev->resource->start,
1578			   resource_size(pdev->resource));
1579 err_request_mem:
1580 err_get_resource:
1581	return err;
1582}
1583
1584static int __exit coh901318_remove(struct platform_device *pdev)
1585{
1586	struct coh901318_base *base = platform_get_drvdata(pdev);
1587
1588	dma_async_device_unregister(&base->dma_memcpy);
1589	dma_async_device_unregister(&base->dma_slave);
1590	coh901318_pool_destroy(&base->pool);
1591	free_irq(platform_get_irq(pdev, 0), base);
1592	iounmap(base->virtbase);
1593	kfree(base);
1594	release_mem_region(pdev->resource->start,
1595			   resource_size(pdev->resource));
1596	return 0;
1597}
1598
1599
1600static struct platform_driver coh901318_driver = {
1601	.remove = __exit_p(coh901318_remove),
1602	.driver = {
1603		.name	= "coh901318",
1604	},
1605};
1606
1607int __init coh901318_init(void)
1608{
1609	return platform_driver_probe(&coh901318_driver, coh901318_probe);
1610}
1611subsys_initcall(coh901318_init);
1612
1613void __exit coh901318_exit(void)
1614{
1615	platform_driver_unregister(&coh901318_driver);
1616}
1617module_exit(coh901318_exit);
1618
1619MODULE_LICENSE("GPL");
1620MODULE_AUTHOR("Per Friden");
1621