1/*
2 * Texas Instruments CPDMA Driver
3 *
4 * Copyright (C) 2010 Texas Instruments
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation version 2.
9 *
10 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11 * kind, whether express or implied; without even the implied warranty
12 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 */
15#include <linux/kernel.h>
16#include <linux/spinlock.h>
17#include <linux/device.h>
18#include <linux/module.h>
19#include <linux/slab.h>
20#include <linux/err.h>
21#include <linux/dma-mapping.h>
22#include <linux/io.h>
23#include <linux/delay.h>
24
25#include "davinci_cpdma.h"
26
27/* DMA Registers */
28#define CPDMA_TXIDVER		0x00
29#define CPDMA_TXCONTROL		0x04
30#define CPDMA_TXTEARDOWN	0x08
31#define CPDMA_RXIDVER		0x10
32#define CPDMA_RXCONTROL		0x14
33#define CPDMA_SOFTRESET		0x1c
34#define CPDMA_RXTEARDOWN	0x18
35#define CPDMA_TXINTSTATRAW	0x80
36#define CPDMA_TXINTSTATMASKED	0x84
37#define CPDMA_TXINTMASKSET	0x88
38#define CPDMA_TXINTMASKCLEAR	0x8c
39#define CPDMA_MACINVECTOR	0x90
40#define CPDMA_MACEOIVECTOR	0x94
41#define CPDMA_RXINTSTATRAW	0xa0
42#define CPDMA_RXINTSTATMASKED	0xa4
43#define CPDMA_RXINTMASKSET	0xa8
44#define CPDMA_RXINTMASKCLEAR	0xac
45#define CPDMA_DMAINTSTATRAW	0xb0
46#define CPDMA_DMAINTSTATMASKED	0xb4
47#define CPDMA_DMAINTMASKSET	0xb8
48#define CPDMA_DMAINTMASKCLEAR	0xbc
49#define CPDMA_DMAINT_HOSTERR	BIT(1)
50
51/* the following exist only if has_ext_regs is set */
52#define CPDMA_DMACONTROL	0x20
53#define CPDMA_DMASTATUS		0x24
54#define CPDMA_RXBUFFOFS		0x28
55#define CPDMA_EM_CONTROL	0x2c
56
57/* Descriptor mode bits */
58#define CPDMA_DESC_SOP		BIT(31)
59#define CPDMA_DESC_EOP		BIT(30)
60#define CPDMA_DESC_OWNER	BIT(29)
61#define CPDMA_DESC_EOQ		BIT(28)
62#define CPDMA_DESC_TD_COMPLETE	BIT(27)
63#define CPDMA_DESC_PASS_CRC	BIT(26)
64#define CPDMA_DESC_TO_PORT_EN	BIT(20)
65#define CPDMA_TO_PORT_SHIFT	16
66#define CPDMA_DESC_PORT_MASK	(BIT(18) | BIT(17) | BIT(16))
67#define CPDMA_DESC_CRC_LEN	4
68
69#define CPDMA_TEARDOWN_VALUE	0xfffffffc
70
71struct cpdma_desc {
72	/* hardware fields */
73	u32			hw_next;
74	u32			hw_buffer;
75	u32			hw_len;
76	u32			hw_mode;
77	/* software fields */
78	void			*sw_token;
79	u32			sw_buffer;
80	u32			sw_len;
81};
82
83struct cpdma_desc_pool {
84	phys_addr_t		phys;
85	u32			hw_addr;
86	void __iomem		*iomap;		/* ioremap map */
87	void			*cpumap;	/* dma_alloc map */
88	int			desc_size, mem_size;
89	int			num_desc, used_desc;
90	unsigned long		*bitmap;
91	struct device		*dev;
92	spinlock_t		lock;
93};
94
95enum cpdma_state {
96	CPDMA_STATE_IDLE,
97	CPDMA_STATE_ACTIVE,
98	CPDMA_STATE_TEARDOWN,
99};
100
101static const char *cpdma_state_str[] = { "idle", "active", "teardown" };
102
103struct cpdma_ctlr {
104	enum cpdma_state	state;
105	struct cpdma_params	params;
106	struct device		*dev;
107	struct cpdma_desc_pool	*pool;
108	spinlock_t		lock;
109	struct cpdma_chan	*channels[2 * CPDMA_MAX_CHANNELS];
110};
111
112struct cpdma_chan {
113	struct cpdma_desc __iomem	*head, *tail;
114	void __iomem			*hdp, *cp, *rxfree;
115	enum cpdma_state		state;
116	struct cpdma_ctlr		*ctlr;
117	int				chan_num;
118	spinlock_t			lock;
119	int				count;
120	u32				mask;
121	cpdma_handler_fn		handler;
122	enum dma_data_direction		dir;
123	struct cpdma_chan_stats		stats;
124	/* offsets into dmaregs */
125	int	int_set, int_clear, td;
126};
127
128/* The following make access to common cpdma_ctlr params more readable */
129#define dmaregs		params.dmaregs
130#define num_chan	params.num_chan
131
132/* various accessors */
133#define dma_reg_read(ctlr, ofs)		__raw_readl((ctlr)->dmaregs + (ofs))
134#define chan_read(chan, fld)		__raw_readl((chan)->fld)
135#define desc_read(desc, fld)		__raw_readl(&(desc)->fld)
136#define dma_reg_write(ctlr, ofs, v)	__raw_writel(v, (ctlr)->dmaregs + (ofs))
137#define chan_write(chan, fld, v)	__raw_writel(v, (chan)->fld)
138#define desc_write(desc, fld, v)	__raw_writel((u32)(v), &(desc)->fld)
139
140#define cpdma_desc_to_port(chan, mode, directed)			\
141	do {								\
142		if (!is_rx_chan(chan) && ((directed == 1) ||		\
143					  (directed == 2)))		\
144			mode |= (CPDMA_DESC_TO_PORT_EN |		\
145				 (directed << CPDMA_TO_PORT_SHIFT));	\
146	} while (0)
147
148/*
149 * Utility constructs for a cpdma descriptor pool.  Some devices (e.g. davinci
150 * emac) have dedicated on-chip memory for these descriptors.  Some other
151 * devices (e.g. cpsw switches) use plain old memory.  Descriptor pools
152 * abstract out these details
153 */
154static struct cpdma_desc_pool *
155cpdma_desc_pool_create(struct device *dev, u32 phys, u32 hw_addr,
156				int size, int align)
157{
158	int bitmap_size;
159	struct cpdma_desc_pool *pool;
160
161	pool = devm_kzalloc(dev, sizeof(*pool), GFP_KERNEL);
162	if (!pool)
163		goto fail;
164
165	spin_lock_init(&pool->lock);
166
167	pool->dev	= dev;
168	pool->mem_size	= size;
169	pool->desc_size	= ALIGN(sizeof(struct cpdma_desc), align);
170	pool->num_desc	= size / pool->desc_size;
171
172	bitmap_size  = (pool->num_desc / BITS_PER_LONG) * sizeof(long);
173	pool->bitmap = devm_kzalloc(dev, bitmap_size, GFP_KERNEL);
174	if (!pool->bitmap)
175		goto fail;
176
177	if (phys) {
178		pool->phys  = phys;
179		pool->iomap = ioremap(phys, size);
180		pool->hw_addr = hw_addr;
181	} else {
182		pool->cpumap = dma_alloc_coherent(dev, size, &pool->phys,
183						  GFP_KERNEL);
184		pool->iomap = pool->cpumap;
185		pool->hw_addr = pool->phys;
186	}
187
188	if (pool->iomap)
189		return pool;
190fail:
191	return NULL;
192}
193
194static void cpdma_desc_pool_destroy(struct cpdma_desc_pool *pool)
195{
196	if (!pool)
197		return;
198
199	WARN_ON(pool->used_desc);
200	if (pool->cpumap) {
201		dma_free_coherent(pool->dev, pool->mem_size, pool->cpumap,
202				  pool->phys);
203	} else {
204		iounmap(pool->iomap);
205	}
206}
207
208static inline dma_addr_t desc_phys(struct cpdma_desc_pool *pool,
209		  struct cpdma_desc __iomem *desc)
210{
211	if (!desc)
212		return 0;
213	return pool->hw_addr + (__force long)desc - (__force long)pool->iomap;
214}
215
216static inline struct cpdma_desc __iomem *
217desc_from_phys(struct cpdma_desc_pool *pool, dma_addr_t dma)
218{
219	return dma ? pool->iomap + dma - pool->hw_addr : NULL;
220}
221
222static struct cpdma_desc __iomem *
223cpdma_desc_alloc(struct cpdma_desc_pool *pool, int num_desc, bool is_rx)
224{
225	unsigned long flags;
226	int index;
227	int desc_start;
228	int desc_end;
229	struct cpdma_desc __iomem *desc = NULL;
230
231	spin_lock_irqsave(&pool->lock, flags);
232
233	if (is_rx) {
234		desc_start = 0;
235		desc_end = pool->num_desc/2;
236	 } else {
237		desc_start = pool->num_desc/2;
238		desc_end = pool->num_desc;
239	}
240
241	index = bitmap_find_next_zero_area(pool->bitmap,
242				desc_end, desc_start, num_desc, 0);
243	if (index < desc_end) {
244		bitmap_set(pool->bitmap, index, num_desc);
245		desc = pool->iomap + pool->desc_size * index;
246		pool->used_desc++;
247	}
248
249	spin_unlock_irqrestore(&pool->lock, flags);
250	return desc;
251}
252
253static void cpdma_desc_free(struct cpdma_desc_pool *pool,
254			    struct cpdma_desc __iomem *desc, int num_desc)
255{
256	unsigned long flags, index;
257
258	index = ((unsigned long)desc - (unsigned long)pool->iomap) /
259		pool->desc_size;
260	spin_lock_irqsave(&pool->lock, flags);
261	bitmap_clear(pool->bitmap, index, num_desc);
262	pool->used_desc--;
263	spin_unlock_irqrestore(&pool->lock, flags);
264}
265
266struct cpdma_ctlr *cpdma_ctlr_create(struct cpdma_params *params)
267{
268	struct cpdma_ctlr *ctlr;
269
270	ctlr = devm_kzalloc(params->dev, sizeof(*ctlr), GFP_KERNEL);
271	if (!ctlr)
272		return NULL;
273
274	ctlr->state = CPDMA_STATE_IDLE;
275	ctlr->params = *params;
276	ctlr->dev = params->dev;
277	spin_lock_init(&ctlr->lock);
278
279	ctlr->pool = cpdma_desc_pool_create(ctlr->dev,
280					    ctlr->params.desc_mem_phys,
281					    ctlr->params.desc_hw_addr,
282					    ctlr->params.desc_mem_size,
283					    ctlr->params.desc_align);
284	if (!ctlr->pool)
285		return NULL;
286
287	if (WARN_ON(ctlr->num_chan > CPDMA_MAX_CHANNELS))
288		ctlr->num_chan = CPDMA_MAX_CHANNELS;
289	return ctlr;
290}
291EXPORT_SYMBOL_GPL(cpdma_ctlr_create);
292
293int cpdma_ctlr_start(struct cpdma_ctlr *ctlr)
294{
295	unsigned long flags;
296	int i;
297
298	spin_lock_irqsave(&ctlr->lock, flags);
299	if (ctlr->state != CPDMA_STATE_IDLE) {
300		spin_unlock_irqrestore(&ctlr->lock, flags);
301		return -EBUSY;
302	}
303
304	if (ctlr->params.has_soft_reset) {
305		unsigned timeout = 10 * 100;
306
307		dma_reg_write(ctlr, CPDMA_SOFTRESET, 1);
308		while (timeout) {
309			if (dma_reg_read(ctlr, CPDMA_SOFTRESET) == 0)
310				break;
311			udelay(10);
312			timeout--;
313		}
314		WARN_ON(!timeout);
315	}
316
317	for (i = 0; i < ctlr->num_chan; i++) {
318		__raw_writel(0, ctlr->params.txhdp + 4 * i);
319		__raw_writel(0, ctlr->params.rxhdp + 4 * i);
320		__raw_writel(0, ctlr->params.txcp + 4 * i);
321		__raw_writel(0, ctlr->params.rxcp + 4 * i);
322	}
323
324	dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
325	dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
326
327	dma_reg_write(ctlr, CPDMA_TXCONTROL, 1);
328	dma_reg_write(ctlr, CPDMA_RXCONTROL, 1);
329
330	ctlr->state = CPDMA_STATE_ACTIVE;
331
332	for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
333		if (ctlr->channels[i])
334			cpdma_chan_start(ctlr->channels[i]);
335	}
336	spin_unlock_irqrestore(&ctlr->lock, flags);
337	return 0;
338}
339EXPORT_SYMBOL_GPL(cpdma_ctlr_start);
340
341int cpdma_ctlr_stop(struct cpdma_ctlr *ctlr)
342{
343	unsigned long flags;
344	int i;
345
346	spin_lock_irqsave(&ctlr->lock, flags);
347	if (ctlr->state == CPDMA_STATE_TEARDOWN) {
348		spin_unlock_irqrestore(&ctlr->lock, flags);
349		return -EINVAL;
350	}
351
352	ctlr->state = CPDMA_STATE_TEARDOWN;
353
354	for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
355		if (ctlr->channels[i])
356			cpdma_chan_stop(ctlr->channels[i]);
357	}
358
359	dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
360	dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
361
362	dma_reg_write(ctlr, CPDMA_TXCONTROL, 0);
363	dma_reg_write(ctlr, CPDMA_RXCONTROL, 0);
364
365	ctlr->state = CPDMA_STATE_IDLE;
366
367	spin_unlock_irqrestore(&ctlr->lock, flags);
368	return 0;
369}
370EXPORT_SYMBOL_GPL(cpdma_ctlr_stop);
371
372int cpdma_ctlr_dump(struct cpdma_ctlr *ctlr)
373{
374	struct device *dev = ctlr->dev;
375	unsigned long flags;
376	int i;
377
378	spin_lock_irqsave(&ctlr->lock, flags);
379
380	dev_info(dev, "CPDMA: state: %s", cpdma_state_str[ctlr->state]);
381
382	dev_info(dev, "CPDMA: txidver: %x",
383		 dma_reg_read(ctlr, CPDMA_TXIDVER));
384	dev_info(dev, "CPDMA: txcontrol: %x",
385		 dma_reg_read(ctlr, CPDMA_TXCONTROL));
386	dev_info(dev, "CPDMA: txteardown: %x",
387		 dma_reg_read(ctlr, CPDMA_TXTEARDOWN));
388	dev_info(dev, "CPDMA: rxidver: %x",
389		 dma_reg_read(ctlr, CPDMA_RXIDVER));
390	dev_info(dev, "CPDMA: rxcontrol: %x",
391		 dma_reg_read(ctlr, CPDMA_RXCONTROL));
392	dev_info(dev, "CPDMA: softreset: %x",
393		 dma_reg_read(ctlr, CPDMA_SOFTRESET));
394	dev_info(dev, "CPDMA: rxteardown: %x",
395		 dma_reg_read(ctlr, CPDMA_RXTEARDOWN));
396	dev_info(dev, "CPDMA: txintstatraw: %x",
397		 dma_reg_read(ctlr, CPDMA_TXINTSTATRAW));
398	dev_info(dev, "CPDMA: txintstatmasked: %x",
399		 dma_reg_read(ctlr, CPDMA_TXINTSTATMASKED));
400	dev_info(dev, "CPDMA: txintmaskset: %x",
401		 dma_reg_read(ctlr, CPDMA_TXINTMASKSET));
402	dev_info(dev, "CPDMA: txintmaskclear: %x",
403		 dma_reg_read(ctlr, CPDMA_TXINTMASKCLEAR));
404	dev_info(dev, "CPDMA: macinvector: %x",
405		 dma_reg_read(ctlr, CPDMA_MACINVECTOR));
406	dev_info(dev, "CPDMA: maceoivector: %x",
407		 dma_reg_read(ctlr, CPDMA_MACEOIVECTOR));
408	dev_info(dev, "CPDMA: rxintstatraw: %x",
409		 dma_reg_read(ctlr, CPDMA_RXINTSTATRAW));
410	dev_info(dev, "CPDMA: rxintstatmasked: %x",
411		 dma_reg_read(ctlr, CPDMA_RXINTSTATMASKED));
412	dev_info(dev, "CPDMA: rxintmaskset: %x",
413		 dma_reg_read(ctlr, CPDMA_RXINTMASKSET));
414	dev_info(dev, "CPDMA: rxintmaskclear: %x",
415		 dma_reg_read(ctlr, CPDMA_RXINTMASKCLEAR));
416	dev_info(dev, "CPDMA: dmaintstatraw: %x",
417		 dma_reg_read(ctlr, CPDMA_DMAINTSTATRAW));
418	dev_info(dev, "CPDMA: dmaintstatmasked: %x",
419		 dma_reg_read(ctlr, CPDMA_DMAINTSTATMASKED));
420	dev_info(dev, "CPDMA: dmaintmaskset: %x",
421		 dma_reg_read(ctlr, CPDMA_DMAINTMASKSET));
422	dev_info(dev, "CPDMA: dmaintmaskclear: %x",
423		 dma_reg_read(ctlr, CPDMA_DMAINTMASKCLEAR));
424
425	if (!ctlr->params.has_ext_regs) {
426		dev_info(dev, "CPDMA: dmacontrol: %x",
427			 dma_reg_read(ctlr, CPDMA_DMACONTROL));
428		dev_info(dev, "CPDMA: dmastatus: %x",
429			 dma_reg_read(ctlr, CPDMA_DMASTATUS));
430		dev_info(dev, "CPDMA: rxbuffofs: %x",
431			 dma_reg_read(ctlr, CPDMA_RXBUFFOFS));
432	}
433
434	for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
435		if (ctlr->channels[i])
436			cpdma_chan_dump(ctlr->channels[i]);
437
438	spin_unlock_irqrestore(&ctlr->lock, flags);
439	return 0;
440}
441EXPORT_SYMBOL_GPL(cpdma_ctlr_dump);
442
443int cpdma_ctlr_destroy(struct cpdma_ctlr *ctlr)
444{
445	unsigned long flags;
446	int ret = 0, i;
447
448	if (!ctlr)
449		return -EINVAL;
450
451	spin_lock_irqsave(&ctlr->lock, flags);
452	if (ctlr->state != CPDMA_STATE_IDLE)
453		cpdma_ctlr_stop(ctlr);
454
455	for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
456		cpdma_chan_destroy(ctlr->channels[i]);
457
458	cpdma_desc_pool_destroy(ctlr->pool);
459	spin_unlock_irqrestore(&ctlr->lock, flags);
460	return ret;
461}
462EXPORT_SYMBOL_GPL(cpdma_ctlr_destroy);
463
464int cpdma_ctlr_int_ctrl(struct cpdma_ctlr *ctlr, bool enable)
465{
466	unsigned long flags;
467	int i, reg;
468
469	spin_lock_irqsave(&ctlr->lock, flags);
470	if (ctlr->state != CPDMA_STATE_ACTIVE) {
471		spin_unlock_irqrestore(&ctlr->lock, flags);
472		return -EINVAL;
473	}
474
475	reg = enable ? CPDMA_DMAINTMASKSET : CPDMA_DMAINTMASKCLEAR;
476	dma_reg_write(ctlr, reg, CPDMA_DMAINT_HOSTERR);
477
478	for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
479		if (ctlr->channels[i])
480			cpdma_chan_int_ctrl(ctlr->channels[i], enable);
481	}
482
483	spin_unlock_irqrestore(&ctlr->lock, flags);
484	return 0;
485}
486EXPORT_SYMBOL_GPL(cpdma_ctlr_int_ctrl);
487
488void cpdma_ctlr_eoi(struct cpdma_ctlr *ctlr, u32 value)
489{
490	dma_reg_write(ctlr, CPDMA_MACEOIVECTOR, value);
491}
492EXPORT_SYMBOL_GPL(cpdma_ctlr_eoi);
493
494struct cpdma_chan *cpdma_chan_create(struct cpdma_ctlr *ctlr, int chan_num,
495				     cpdma_handler_fn handler)
496{
497	struct cpdma_chan *chan;
498	int offset = (chan_num % CPDMA_MAX_CHANNELS) * 4;
499	unsigned long flags;
500
501	if (__chan_linear(chan_num) >= ctlr->num_chan)
502		return NULL;
503
504	chan = devm_kzalloc(ctlr->dev, sizeof(*chan), GFP_KERNEL);
505	if (!chan)
506		return ERR_PTR(-ENOMEM);
507
508	spin_lock_irqsave(&ctlr->lock, flags);
509	if (ctlr->channels[chan_num]) {
510		spin_unlock_irqrestore(&ctlr->lock, flags);
511		devm_kfree(ctlr->dev, chan);
512		return ERR_PTR(-EBUSY);
513	}
514
515	chan->ctlr	= ctlr;
516	chan->state	= CPDMA_STATE_IDLE;
517	chan->chan_num	= chan_num;
518	chan->handler	= handler;
519
520	if (is_rx_chan(chan)) {
521		chan->hdp	= ctlr->params.rxhdp + offset;
522		chan->cp	= ctlr->params.rxcp + offset;
523		chan->rxfree	= ctlr->params.rxfree + offset;
524		chan->int_set	= CPDMA_RXINTMASKSET;
525		chan->int_clear	= CPDMA_RXINTMASKCLEAR;
526		chan->td	= CPDMA_RXTEARDOWN;
527		chan->dir	= DMA_FROM_DEVICE;
528	} else {
529		chan->hdp	= ctlr->params.txhdp + offset;
530		chan->cp	= ctlr->params.txcp + offset;
531		chan->int_set	= CPDMA_TXINTMASKSET;
532		chan->int_clear	= CPDMA_TXINTMASKCLEAR;
533		chan->td	= CPDMA_TXTEARDOWN;
534		chan->dir	= DMA_TO_DEVICE;
535	}
536	chan->mask = BIT(chan_linear(chan));
537
538	spin_lock_init(&chan->lock);
539
540	ctlr->channels[chan_num] = chan;
541	spin_unlock_irqrestore(&ctlr->lock, flags);
542	return chan;
543}
544EXPORT_SYMBOL_GPL(cpdma_chan_create);
545
546int cpdma_chan_destroy(struct cpdma_chan *chan)
547{
548	struct cpdma_ctlr *ctlr;
549	unsigned long flags;
550
551	if (!chan)
552		return -EINVAL;
553	ctlr = chan->ctlr;
554
555	spin_lock_irqsave(&ctlr->lock, flags);
556	if (chan->state != CPDMA_STATE_IDLE)
557		cpdma_chan_stop(chan);
558	ctlr->channels[chan->chan_num] = NULL;
559	spin_unlock_irqrestore(&ctlr->lock, flags);
560	return 0;
561}
562EXPORT_SYMBOL_GPL(cpdma_chan_destroy);
563
564int cpdma_chan_get_stats(struct cpdma_chan *chan,
565			 struct cpdma_chan_stats *stats)
566{
567	unsigned long flags;
568	if (!chan)
569		return -EINVAL;
570	spin_lock_irqsave(&chan->lock, flags);
571	memcpy(stats, &chan->stats, sizeof(*stats));
572	spin_unlock_irqrestore(&chan->lock, flags);
573	return 0;
574}
575EXPORT_SYMBOL_GPL(cpdma_chan_get_stats);
576
577int cpdma_chan_dump(struct cpdma_chan *chan)
578{
579	unsigned long flags;
580	struct device *dev = chan->ctlr->dev;
581
582	spin_lock_irqsave(&chan->lock, flags);
583
584	dev_info(dev, "channel %d (%s %d) state %s",
585		 chan->chan_num, is_rx_chan(chan) ? "rx" : "tx",
586		 chan_linear(chan), cpdma_state_str[chan->state]);
587	dev_info(dev, "\thdp: %x\n", chan_read(chan, hdp));
588	dev_info(dev, "\tcp: %x\n", chan_read(chan, cp));
589	if (chan->rxfree) {
590		dev_info(dev, "\trxfree: %x\n",
591			 chan_read(chan, rxfree));
592	}
593
594	dev_info(dev, "\tstats head_enqueue: %d\n",
595		 chan->stats.head_enqueue);
596	dev_info(dev, "\tstats tail_enqueue: %d\n",
597		 chan->stats.tail_enqueue);
598	dev_info(dev, "\tstats pad_enqueue: %d\n",
599		 chan->stats.pad_enqueue);
600	dev_info(dev, "\tstats misqueued: %d\n",
601		 chan->stats.misqueued);
602	dev_info(dev, "\tstats desc_alloc_fail: %d\n",
603		 chan->stats.desc_alloc_fail);
604	dev_info(dev, "\tstats pad_alloc_fail: %d\n",
605		 chan->stats.pad_alloc_fail);
606	dev_info(dev, "\tstats runt_receive_buff: %d\n",
607		 chan->stats.runt_receive_buff);
608	dev_info(dev, "\tstats runt_transmit_buff: %d\n",
609		 chan->stats.runt_transmit_buff);
610	dev_info(dev, "\tstats empty_dequeue: %d\n",
611		 chan->stats.empty_dequeue);
612	dev_info(dev, "\tstats busy_dequeue: %d\n",
613		 chan->stats.busy_dequeue);
614	dev_info(dev, "\tstats good_dequeue: %d\n",
615		 chan->stats.good_dequeue);
616	dev_info(dev, "\tstats requeue: %d\n",
617		 chan->stats.requeue);
618	dev_info(dev, "\tstats teardown_dequeue: %d\n",
619		 chan->stats.teardown_dequeue);
620
621	spin_unlock_irqrestore(&chan->lock, flags);
622	return 0;
623}
624
625static void __cpdma_chan_submit(struct cpdma_chan *chan,
626				struct cpdma_desc __iomem *desc)
627{
628	struct cpdma_ctlr		*ctlr = chan->ctlr;
629	struct cpdma_desc __iomem	*prev = chan->tail;
630	struct cpdma_desc_pool		*pool = ctlr->pool;
631	dma_addr_t			desc_dma;
632	u32				mode;
633
634	desc_dma = desc_phys(pool, desc);
635
636	/* simple case - idle channel */
637	if (!chan->head) {
638		chan->stats.head_enqueue++;
639		chan->head = desc;
640		chan->tail = desc;
641		if (chan->state == CPDMA_STATE_ACTIVE)
642			chan_write(chan, hdp, desc_dma);
643		return;
644	}
645
646	/* first chain the descriptor at the tail of the list */
647	desc_write(prev, hw_next, desc_dma);
648	chan->tail = desc;
649	chan->stats.tail_enqueue++;
650
651	/* next check if EOQ has been triggered already */
652	mode = desc_read(prev, hw_mode);
653	if (((mode & (CPDMA_DESC_EOQ | CPDMA_DESC_OWNER)) == CPDMA_DESC_EOQ) &&
654	    (chan->state == CPDMA_STATE_ACTIVE)) {
655		desc_write(prev, hw_mode, mode & ~CPDMA_DESC_EOQ);
656		chan_write(chan, hdp, desc_dma);
657		chan->stats.misqueued++;
658	}
659}
660
661int cpdma_chan_submit(struct cpdma_chan *chan, void *token, void *data,
662		      int len, int directed)
663{
664	struct cpdma_ctlr		*ctlr = chan->ctlr;
665	struct cpdma_desc __iomem	*desc;
666	dma_addr_t			buffer;
667	unsigned long			flags;
668	u32				mode;
669	int				ret = 0;
670
671	spin_lock_irqsave(&chan->lock, flags);
672
673	if (chan->state == CPDMA_STATE_TEARDOWN) {
674		ret = -EINVAL;
675		goto unlock_ret;
676	}
677
678	desc = cpdma_desc_alloc(ctlr->pool, 1, is_rx_chan(chan));
679	if (!desc) {
680		chan->stats.desc_alloc_fail++;
681		ret = -ENOMEM;
682		goto unlock_ret;
683	}
684
685	if (len < ctlr->params.min_packet_size) {
686		len = ctlr->params.min_packet_size;
687		chan->stats.runt_transmit_buff++;
688	}
689
690	buffer = dma_map_single(ctlr->dev, data, len, chan->dir);
691	ret = dma_mapping_error(ctlr->dev, buffer);
692	if (ret) {
693		cpdma_desc_free(ctlr->pool, desc, 1);
694		ret = -EINVAL;
695		goto unlock_ret;
696	}
697
698	mode = CPDMA_DESC_OWNER | CPDMA_DESC_SOP | CPDMA_DESC_EOP;
699	cpdma_desc_to_port(chan, mode, directed);
700
701	desc_write(desc, hw_next,   0);
702	desc_write(desc, hw_buffer, buffer);
703	desc_write(desc, hw_len,    len);
704	desc_write(desc, hw_mode,   mode | len);
705	desc_write(desc, sw_token,  token);
706	desc_write(desc, sw_buffer, buffer);
707	desc_write(desc, sw_len,    len);
708
709	__cpdma_chan_submit(chan, desc);
710
711	if (chan->state == CPDMA_STATE_ACTIVE && chan->rxfree)
712		chan_write(chan, rxfree, 1);
713
714	chan->count++;
715
716unlock_ret:
717	spin_unlock_irqrestore(&chan->lock, flags);
718	return ret;
719}
720EXPORT_SYMBOL_GPL(cpdma_chan_submit);
721
722bool cpdma_check_free_tx_desc(struct cpdma_chan *chan)
723{
724	unsigned long flags;
725	int index;
726	bool ret;
727	struct cpdma_ctlr	*ctlr = chan->ctlr;
728	struct cpdma_desc_pool	*pool = ctlr->pool;
729
730	spin_lock_irqsave(&pool->lock, flags);
731
732	index = bitmap_find_next_zero_area(pool->bitmap,
733				pool->num_desc, pool->num_desc/2, 1, 0);
734
735	if (index < pool->num_desc)
736		ret = true;
737	else
738		ret = false;
739
740	spin_unlock_irqrestore(&pool->lock, flags);
741	return ret;
742}
743EXPORT_SYMBOL_GPL(cpdma_check_free_tx_desc);
744
745static void __cpdma_chan_free(struct cpdma_chan *chan,
746			      struct cpdma_desc __iomem *desc,
747			      int outlen, int status)
748{
749	struct cpdma_ctlr		*ctlr = chan->ctlr;
750	struct cpdma_desc_pool		*pool = ctlr->pool;
751	dma_addr_t			buff_dma;
752	int				origlen;
753	void				*token;
754
755	token      = (void *)desc_read(desc, sw_token);
756	buff_dma   = desc_read(desc, sw_buffer);
757	origlen    = desc_read(desc, sw_len);
758
759	dma_unmap_single(ctlr->dev, buff_dma, origlen, chan->dir);
760	cpdma_desc_free(pool, desc, 1);
761	(*chan->handler)(token, outlen, status);
762}
763
764static int __cpdma_chan_process(struct cpdma_chan *chan)
765{
766	struct cpdma_ctlr		*ctlr = chan->ctlr;
767	struct cpdma_desc __iomem	*desc;
768	int				status, outlen;
769	int				cb_status = 0;
770	struct cpdma_desc_pool		*pool = ctlr->pool;
771	dma_addr_t			desc_dma;
772	unsigned long			flags;
773
774	spin_lock_irqsave(&chan->lock, flags);
775
776	desc = chan->head;
777	if (!desc) {
778		chan->stats.empty_dequeue++;
779		status = -ENOENT;
780		goto unlock_ret;
781	}
782	desc_dma = desc_phys(pool, desc);
783
784	status	= __raw_readl(&desc->hw_mode);
785	outlen	= status & 0x7ff;
786	if (status & CPDMA_DESC_OWNER) {
787		chan->stats.busy_dequeue++;
788		status = -EBUSY;
789		goto unlock_ret;
790	}
791
792	if (status & CPDMA_DESC_PASS_CRC)
793		outlen -= CPDMA_DESC_CRC_LEN;
794
795	status	= status & (CPDMA_DESC_EOQ | CPDMA_DESC_TD_COMPLETE |
796			    CPDMA_DESC_PORT_MASK);
797
798	chan->head = desc_from_phys(pool, desc_read(desc, hw_next));
799	chan_write(chan, cp, desc_dma);
800	chan->count--;
801	chan->stats.good_dequeue++;
802
803	if (status & CPDMA_DESC_EOQ) {
804		chan->stats.requeue++;
805		chan_write(chan, hdp, desc_phys(pool, chan->head));
806	}
807
808	spin_unlock_irqrestore(&chan->lock, flags);
809	if (unlikely(status & CPDMA_DESC_TD_COMPLETE))
810		cb_status = -ENOSYS;
811	else
812		cb_status = status;
813
814	__cpdma_chan_free(chan, desc, outlen, cb_status);
815	return status;
816
817unlock_ret:
818	spin_unlock_irqrestore(&chan->lock, flags);
819	return status;
820}
821
822int cpdma_chan_process(struct cpdma_chan *chan, int quota)
823{
824	int used = 0, ret = 0;
825
826	if (chan->state != CPDMA_STATE_ACTIVE)
827		return -EINVAL;
828
829	while (used < quota) {
830		ret = __cpdma_chan_process(chan);
831		if (ret < 0)
832			break;
833		used++;
834	}
835	return used;
836}
837EXPORT_SYMBOL_GPL(cpdma_chan_process);
838
839int cpdma_chan_start(struct cpdma_chan *chan)
840{
841	struct cpdma_ctlr	*ctlr = chan->ctlr;
842	struct cpdma_desc_pool	*pool = ctlr->pool;
843	unsigned long		flags;
844
845	spin_lock_irqsave(&chan->lock, flags);
846	if (chan->state != CPDMA_STATE_IDLE) {
847		spin_unlock_irqrestore(&chan->lock, flags);
848		return -EBUSY;
849	}
850	if (ctlr->state != CPDMA_STATE_ACTIVE) {
851		spin_unlock_irqrestore(&chan->lock, flags);
852		return -EINVAL;
853	}
854	dma_reg_write(ctlr, chan->int_set, chan->mask);
855	chan->state = CPDMA_STATE_ACTIVE;
856	if (chan->head) {
857		chan_write(chan, hdp, desc_phys(pool, chan->head));
858		if (chan->rxfree)
859			chan_write(chan, rxfree, chan->count);
860	}
861
862	spin_unlock_irqrestore(&chan->lock, flags);
863	return 0;
864}
865EXPORT_SYMBOL_GPL(cpdma_chan_start);
866
867int cpdma_chan_stop(struct cpdma_chan *chan)
868{
869	struct cpdma_ctlr	*ctlr = chan->ctlr;
870	struct cpdma_desc_pool	*pool = ctlr->pool;
871	unsigned long		flags;
872	int			ret;
873	unsigned		timeout;
874
875	spin_lock_irqsave(&chan->lock, flags);
876	if (chan->state == CPDMA_STATE_TEARDOWN) {
877		spin_unlock_irqrestore(&chan->lock, flags);
878		return -EINVAL;
879	}
880
881	chan->state = CPDMA_STATE_TEARDOWN;
882	dma_reg_write(ctlr, chan->int_clear, chan->mask);
883
884	/* trigger teardown */
885	dma_reg_write(ctlr, chan->td, chan_linear(chan));
886
887	/* wait for teardown complete */
888	timeout = 100 * 100; /* 100 ms */
889	while (timeout) {
890		u32 cp = chan_read(chan, cp);
891		if ((cp & CPDMA_TEARDOWN_VALUE) == CPDMA_TEARDOWN_VALUE)
892			break;
893		udelay(10);
894		timeout--;
895	}
896	WARN_ON(!timeout);
897	chan_write(chan, cp, CPDMA_TEARDOWN_VALUE);
898
899	/* handle completed packets */
900	spin_unlock_irqrestore(&chan->lock, flags);
901	do {
902		ret = __cpdma_chan_process(chan);
903		if (ret < 0)
904			break;
905	} while ((ret & CPDMA_DESC_TD_COMPLETE) == 0);
906	spin_lock_irqsave(&chan->lock, flags);
907
908	/* remaining packets haven't been tx/rx'ed, clean them up */
909	while (chan->head) {
910		struct cpdma_desc __iomem *desc = chan->head;
911		dma_addr_t next_dma;
912
913		next_dma = desc_read(desc, hw_next);
914		chan->head = desc_from_phys(pool, next_dma);
915		chan->count--;
916		chan->stats.teardown_dequeue++;
917
918		/* issue callback without locks held */
919		spin_unlock_irqrestore(&chan->lock, flags);
920		__cpdma_chan_free(chan, desc, 0, -ENOSYS);
921		spin_lock_irqsave(&chan->lock, flags);
922	}
923
924	chan->state = CPDMA_STATE_IDLE;
925	spin_unlock_irqrestore(&chan->lock, flags);
926	return 0;
927}
928EXPORT_SYMBOL_GPL(cpdma_chan_stop);
929
930int cpdma_chan_int_ctrl(struct cpdma_chan *chan, bool enable)
931{
932	unsigned long flags;
933
934	spin_lock_irqsave(&chan->lock, flags);
935	if (chan->state != CPDMA_STATE_ACTIVE) {
936		spin_unlock_irqrestore(&chan->lock, flags);
937		return -EINVAL;
938	}
939
940	dma_reg_write(chan->ctlr, enable ? chan->int_set : chan->int_clear,
941		      chan->mask);
942	spin_unlock_irqrestore(&chan->lock, flags);
943
944	return 0;
945}
946
947struct cpdma_control_info {
948	u32		reg;
949	u32		shift, mask;
950	int		access;
951#define ACCESS_RO	BIT(0)
952#define ACCESS_WO	BIT(1)
953#define ACCESS_RW	(ACCESS_RO | ACCESS_WO)
954};
955
956static struct cpdma_control_info controls[] = {
957	[CPDMA_CMD_IDLE]	  = {CPDMA_DMACONTROL,	3,  1,      ACCESS_WO},
958	[CPDMA_COPY_ERROR_FRAMES] = {CPDMA_DMACONTROL,	4,  1,      ACCESS_RW},
959	[CPDMA_RX_OFF_LEN_UPDATE] = {CPDMA_DMACONTROL,	2,  1,      ACCESS_RW},
960	[CPDMA_RX_OWNERSHIP_FLIP] = {CPDMA_DMACONTROL,	1,  1,      ACCESS_RW},
961	[CPDMA_TX_PRIO_FIXED]	  = {CPDMA_DMACONTROL,	0,  1,      ACCESS_RW},
962	[CPDMA_STAT_IDLE]	  = {CPDMA_DMASTATUS,	31, 1,      ACCESS_RO},
963	[CPDMA_STAT_TX_ERR_CODE]  = {CPDMA_DMASTATUS,	20, 0xf,    ACCESS_RW},
964	[CPDMA_STAT_TX_ERR_CHAN]  = {CPDMA_DMASTATUS,	16, 0x7,    ACCESS_RW},
965	[CPDMA_STAT_RX_ERR_CODE]  = {CPDMA_DMASTATUS,	12, 0xf,    ACCESS_RW},
966	[CPDMA_STAT_RX_ERR_CHAN]  = {CPDMA_DMASTATUS,	8,  0x7,    ACCESS_RW},
967	[CPDMA_RX_BUFFER_OFFSET]  = {CPDMA_RXBUFFOFS,	0,  0xffff, ACCESS_RW},
968};
969
970int cpdma_control_get(struct cpdma_ctlr *ctlr, int control)
971{
972	unsigned long flags;
973	struct cpdma_control_info *info = &controls[control];
974	int ret;
975
976	spin_lock_irqsave(&ctlr->lock, flags);
977
978	ret = -ENOTSUPP;
979	if (!ctlr->params.has_ext_regs)
980		goto unlock_ret;
981
982	ret = -EINVAL;
983	if (ctlr->state != CPDMA_STATE_ACTIVE)
984		goto unlock_ret;
985
986	ret = -ENOENT;
987	if (control < 0 || control >= ARRAY_SIZE(controls))
988		goto unlock_ret;
989
990	ret = -EPERM;
991	if ((info->access & ACCESS_RO) != ACCESS_RO)
992		goto unlock_ret;
993
994	ret = (dma_reg_read(ctlr, info->reg) >> info->shift) & info->mask;
995
996unlock_ret:
997	spin_unlock_irqrestore(&ctlr->lock, flags);
998	return ret;
999}
1000
1001int cpdma_control_set(struct cpdma_ctlr *ctlr, int control, int value)
1002{
1003	unsigned long flags;
1004	struct cpdma_control_info *info = &controls[control];
1005	int ret;
1006	u32 val;
1007
1008	spin_lock_irqsave(&ctlr->lock, flags);
1009
1010	ret = -ENOTSUPP;
1011	if (!ctlr->params.has_ext_regs)
1012		goto unlock_ret;
1013
1014	ret = -EINVAL;
1015	if (ctlr->state != CPDMA_STATE_ACTIVE)
1016		goto unlock_ret;
1017
1018	ret = -ENOENT;
1019	if (control < 0 || control >= ARRAY_SIZE(controls))
1020		goto unlock_ret;
1021
1022	ret = -EPERM;
1023	if ((info->access & ACCESS_WO) != ACCESS_WO)
1024		goto unlock_ret;
1025
1026	val  = dma_reg_read(ctlr, info->reg);
1027	val &= ~(info->mask << info->shift);
1028	val |= (value & info->mask) << info->shift;
1029	dma_reg_write(ctlr, info->reg, val);
1030	ret = 0;
1031
1032unlock_ret:
1033	spin_unlock_irqrestore(&ctlr->lock, flags);
1034	return ret;
1035}
1036EXPORT_SYMBOL_GPL(cpdma_control_set);
1037
1038MODULE_LICENSE("GPL");
1039