1/*
2 * Copyright (C) 2014 Texas Instruments Incorporated
3 * Authors:	Santosh Shilimkar <santosh.shilimkar@ti.com>
4 *		Sandeep Nair <sandeep_n@ti.com>
5 *		Cyril Chemparathy <cyril@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation version 2.
10 *
11 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12 * kind, whether express or implied; without even the implied warranty
13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 */
16
17#include <linux/io.h>
18#include <linux/sched.h>
19#include <linux/module.h>
20#include <linux/dma-direction.h>
21#include <linux/interrupt.h>
22#include <linux/pm_runtime.h>
23#include <linux/of_dma.h>
24#include <linux/of_address.h>
25#include <linux/platform_device.h>
26#include <linux/soc/ti/knav_dma.h>
27#include <linux/debugfs.h>
28#include <linux/seq_file.h>
29
30#define REG_MASK		0xffffffff
31
32#define DMA_LOOPBACK		BIT(31)
33#define DMA_ENABLE		BIT(31)
34#define DMA_TEARDOWN		BIT(30)
35
36#define DMA_TX_FILT_PSWORDS	BIT(29)
37#define DMA_TX_FILT_EINFO	BIT(30)
38#define DMA_TX_PRIO_SHIFT	0
39#define DMA_RX_PRIO_SHIFT	16
40#define DMA_PRIO_MASK		GENMASK(3, 0)
41#define DMA_PRIO_DEFAULT	0
42#define DMA_RX_TIMEOUT_DEFAULT	17500 /* cycles */
43#define DMA_RX_TIMEOUT_MASK	GENMASK(16, 0)
44#define DMA_RX_TIMEOUT_SHIFT	0
45
46#define CHAN_HAS_EPIB		BIT(30)
47#define CHAN_HAS_PSINFO		BIT(29)
48#define CHAN_ERR_RETRY		BIT(28)
49#define CHAN_PSINFO_AT_SOP	BIT(25)
50#define CHAN_SOP_OFF_SHIFT	16
51#define CHAN_SOP_OFF_MASK	GENMASK(9, 0)
52#define DESC_TYPE_SHIFT		26
53#define DESC_TYPE_MASK		GENMASK(2, 0)
54
55/*
56 * QMGR & QNUM together make up 14 bits with QMGR as the 2 MSb's in the logical
57 * navigator cloud mapping scheme.
58 * using the 14bit physical queue numbers directly maps into this scheme.
59 */
60#define CHAN_QNUM_MASK		GENMASK(14, 0)
61#define DMA_MAX_QMS		4
62#define DMA_TIMEOUT		1	/* msecs */
63#define DMA_INVALID_ID		0xffff
64
65struct reg_global {
66	u32	revision;
67	u32	perf_control;
68	u32	emulation_control;
69	u32	priority_control;
70	u32	qm_base_address[DMA_MAX_QMS];
71};
72
73struct reg_chan {
74	u32	control;
75	u32	mode;
76	u32	__rsvd[6];
77};
78
79struct reg_tx_sched {
80	u32	prio;
81};
82
83struct reg_rx_flow {
84	u32	control;
85	u32	tags;
86	u32	tag_sel;
87	u32	fdq_sel[2];
88	u32	thresh[3];
89};
90
91struct knav_dma_pool_device {
92	struct device			*dev;
93	struct list_head		list;
94};
95
96struct knav_dma_device {
97	bool				loopback, enable_all;
98	unsigned			tx_priority, rx_priority, rx_timeout;
99	unsigned			logical_queue_managers;
100	unsigned			qm_base_address[DMA_MAX_QMS];
101	struct reg_global __iomem	*reg_global;
102	struct reg_chan __iomem		*reg_tx_chan;
103	struct reg_rx_flow __iomem	*reg_rx_flow;
104	struct reg_chan __iomem		*reg_rx_chan;
105	struct reg_tx_sched __iomem	*reg_tx_sched;
106	unsigned			max_rx_chan, max_tx_chan;
107	unsigned			max_rx_flow;
108	char				name[32];
109	atomic_t			ref_count;
110	struct list_head		list;
111	struct list_head		chan_list;
112	spinlock_t			lock;
113};
114
115struct knav_dma_chan {
116	enum dma_transfer_direction	direction;
117	struct knav_dma_device		*dma;
118	atomic_t			ref_count;
119
120	/* registers */
121	struct reg_chan __iomem		*reg_chan;
122	struct reg_tx_sched __iomem	*reg_tx_sched;
123	struct reg_rx_flow __iomem	*reg_rx_flow;
124
125	/* configuration stuff */
126	unsigned			channel, flow;
127	struct knav_dma_cfg		cfg;
128	struct list_head		list;
129	spinlock_t			lock;
130};
131
132#define chan_number(ch)	((ch->direction == DMA_MEM_TO_DEV) ? \
133			ch->channel : ch->flow)
134
135static struct knav_dma_pool_device *kdev;
136
137static bool check_config(struct knav_dma_chan *chan, struct knav_dma_cfg *cfg)
138{
139	if (!memcmp(&chan->cfg, cfg, sizeof(*cfg)))
140		return true;
141	else
142		return false;
143}
144
145static int chan_start(struct knav_dma_chan *chan,
146			struct knav_dma_cfg *cfg)
147{
148	u32 v = 0;
149
150	spin_lock(&chan->lock);
151	if ((chan->direction == DMA_MEM_TO_DEV) && chan->reg_chan) {
152		if (cfg->u.tx.filt_pswords)
153			v |= DMA_TX_FILT_PSWORDS;
154		if (cfg->u.tx.filt_einfo)
155			v |= DMA_TX_FILT_EINFO;
156		writel_relaxed(v, &chan->reg_chan->mode);
157		writel_relaxed(DMA_ENABLE, &chan->reg_chan->control);
158	}
159
160	if (chan->reg_tx_sched)
161		writel_relaxed(cfg->u.tx.priority, &chan->reg_tx_sched->prio);
162
163	if (chan->reg_rx_flow) {
164		v = 0;
165
166		if (cfg->u.rx.einfo_present)
167			v |= CHAN_HAS_EPIB;
168		if (cfg->u.rx.psinfo_present)
169			v |= CHAN_HAS_PSINFO;
170		if (cfg->u.rx.err_mode == DMA_RETRY)
171			v |= CHAN_ERR_RETRY;
172		v |= (cfg->u.rx.desc_type & DESC_TYPE_MASK) << DESC_TYPE_SHIFT;
173		if (cfg->u.rx.psinfo_at_sop)
174			v |= CHAN_PSINFO_AT_SOP;
175		v |= (cfg->u.rx.sop_offset & CHAN_SOP_OFF_MASK)
176			<< CHAN_SOP_OFF_SHIFT;
177		v |= cfg->u.rx.dst_q & CHAN_QNUM_MASK;
178
179		writel_relaxed(v, &chan->reg_rx_flow->control);
180		writel_relaxed(0, &chan->reg_rx_flow->tags);
181		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
182
183		v =  cfg->u.rx.fdq[0] << 16;
184		v |=  cfg->u.rx.fdq[1] & CHAN_QNUM_MASK;
185		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[0]);
186
187		v =  cfg->u.rx.fdq[2] << 16;
188		v |=  cfg->u.rx.fdq[3] & CHAN_QNUM_MASK;
189		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[1]);
190
191		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
192		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
193		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
194	}
195
196	/* Keep a copy of the cfg */
197	memcpy(&chan->cfg, cfg, sizeof(*cfg));
198	spin_unlock(&chan->lock);
199
200	return 0;
201}
202
203static int chan_teardown(struct knav_dma_chan *chan)
204{
205	unsigned long end, value;
206
207	if (!chan->reg_chan)
208		return 0;
209
210	/* indicate teardown */
211	writel_relaxed(DMA_TEARDOWN, &chan->reg_chan->control);
212
213	/* wait for the dma to shut itself down */
214	end = jiffies + msecs_to_jiffies(DMA_TIMEOUT);
215	do {
216		value = readl_relaxed(&chan->reg_chan->control);
217		if ((value & DMA_ENABLE) == 0)
218			break;
219	} while (time_after(end, jiffies));
220
221	if (readl_relaxed(&chan->reg_chan->control) & DMA_ENABLE) {
222		dev_err(kdev->dev, "timeout waiting for teardown\n");
223		return -ETIMEDOUT;
224	}
225
226	return 0;
227}
228
229static void chan_stop(struct knav_dma_chan *chan)
230{
231	spin_lock(&chan->lock);
232	if (chan->reg_rx_flow) {
233		/* first detach fdqs, starve out the flow */
234		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[0]);
235		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[1]);
236		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
237		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
238		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
239	}
240
241	/* teardown the dma channel */
242	chan_teardown(chan);
243
244	/* then disconnect the completion side */
245	if (chan->reg_rx_flow) {
246		writel_relaxed(0, &chan->reg_rx_flow->control);
247		writel_relaxed(0, &chan->reg_rx_flow->tags);
248		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
249	}
250
251	memset(&chan->cfg, 0, sizeof(struct knav_dma_cfg));
252	spin_unlock(&chan->lock);
253
254	dev_dbg(kdev->dev, "channel stopped\n");
255}
256
257static void dma_hw_enable_all(struct knav_dma_device *dma)
258{
259	int i;
260
261	for (i = 0; i < dma->max_tx_chan; i++) {
262		writel_relaxed(0, &dma->reg_tx_chan[i].mode);
263		writel_relaxed(DMA_ENABLE, &dma->reg_tx_chan[i].control);
264	}
265}
266
267
268static void knav_dma_hw_init(struct knav_dma_device *dma)
269{
270	unsigned v;
271	int i;
272
273	spin_lock(&dma->lock);
274	v  = dma->loopback ? DMA_LOOPBACK : 0;
275	writel_relaxed(v, &dma->reg_global->emulation_control);
276
277	v = readl_relaxed(&dma->reg_global->perf_control);
278	v |= ((dma->rx_timeout & DMA_RX_TIMEOUT_MASK) << DMA_RX_TIMEOUT_SHIFT);
279	writel_relaxed(v, &dma->reg_global->perf_control);
280
281	v = ((dma->tx_priority << DMA_TX_PRIO_SHIFT) |
282	     (dma->rx_priority << DMA_RX_PRIO_SHIFT));
283
284	writel_relaxed(v, &dma->reg_global->priority_control);
285
286	/* Always enable all Rx channels. Rx paths are managed using flows */
287	for (i = 0; i < dma->max_rx_chan; i++)
288		writel_relaxed(DMA_ENABLE, &dma->reg_rx_chan[i].control);
289
290	for (i = 0; i < dma->logical_queue_managers; i++)
291		writel_relaxed(dma->qm_base_address[i],
292			       &dma->reg_global->qm_base_address[i]);
293	spin_unlock(&dma->lock);
294}
295
296static void knav_dma_hw_destroy(struct knav_dma_device *dma)
297{
298	int i;
299	unsigned v;
300
301	spin_lock(&dma->lock);
302	v = ~DMA_ENABLE & REG_MASK;
303
304	for (i = 0; i < dma->max_rx_chan; i++)
305		writel_relaxed(v, &dma->reg_rx_chan[i].control);
306
307	for (i = 0; i < dma->max_tx_chan; i++)
308		writel_relaxed(v, &dma->reg_tx_chan[i].control);
309	spin_unlock(&dma->lock);
310}
311
312static void dma_debug_show_channels(struct seq_file *s,
313					struct knav_dma_chan *chan)
314{
315	int i;
316
317	seq_printf(s, "\t%s %d:\t",
318		((chan->direction == DMA_MEM_TO_DEV) ? "tx chan" : "rx flow"),
319		chan_number(chan));
320
321	if (chan->direction == DMA_MEM_TO_DEV) {
322		seq_printf(s, "einfo - %d, pswords - %d, priority - %d\n",
323			chan->cfg.u.tx.filt_einfo,
324			chan->cfg.u.tx.filt_pswords,
325			chan->cfg.u.tx.priority);
326	} else {
327		seq_printf(s, "einfo - %d, psinfo - %d, desc_type - %d\n",
328			chan->cfg.u.rx.einfo_present,
329			chan->cfg.u.rx.psinfo_present,
330			chan->cfg.u.rx.desc_type);
331		seq_printf(s, "\t\t\tdst_q: [%d], thresh: %d fdq: ",
332			chan->cfg.u.rx.dst_q,
333			chan->cfg.u.rx.thresh);
334		for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN; i++)
335			seq_printf(s, "[%d]", chan->cfg.u.rx.fdq[i]);
336		seq_printf(s, "\n");
337	}
338}
339
340static void dma_debug_show_devices(struct seq_file *s,
341					struct knav_dma_device *dma)
342{
343	struct knav_dma_chan *chan;
344
345	list_for_each_entry(chan, &dma->chan_list, list) {
346		if (atomic_read(&chan->ref_count))
347			dma_debug_show_channels(s, chan);
348	}
349}
350
351static int dma_debug_show(struct seq_file *s, void *v)
352{
353	struct knav_dma_device *dma;
354
355	list_for_each_entry(dma, &kdev->list, list) {
356		if (atomic_read(&dma->ref_count)) {
357			seq_printf(s, "%s : max_tx_chan: (%d), max_rx_flows: (%d)\n",
358			dma->name, dma->max_tx_chan, dma->max_rx_flow);
359			dma_debug_show_devices(s, dma);
360		}
361	}
362
363	return 0;
364}
365
366static int knav_dma_debug_open(struct inode *inode, struct file *file)
367{
368	return single_open(file, dma_debug_show, NULL);
369}
370
371static const struct file_operations knav_dma_debug_ops = {
372	.open		= knav_dma_debug_open,
373	.read		= seq_read,
374	.llseek		= seq_lseek,
375	.release	= single_release,
376};
377
378static int of_channel_match_helper(struct device_node *np, const char *name,
379					const char **dma_instance)
380{
381	struct of_phandle_args args;
382	struct device_node *dma_node;
383	int index;
384
385	dma_node = of_parse_phandle(np, "ti,navigator-dmas", 0);
386	if (!dma_node)
387		return -ENODEV;
388
389	*dma_instance = dma_node->name;
390	index = of_property_match_string(np, "ti,navigator-dma-names", name);
391	if (index < 0) {
392		dev_err(kdev->dev, "No 'ti,navigator-dma-names' propery\n");
393		return -ENODEV;
394	}
395
396	if (of_parse_phandle_with_fixed_args(np, "ti,navigator-dmas",
397					1, index, &args)) {
398		dev_err(kdev->dev, "Missing the pahndle args name %s\n", name);
399		return -ENODEV;
400	}
401
402	if (args.args[0] < 0) {
403		dev_err(kdev->dev, "Missing args for %s\n", name);
404		return -ENODEV;
405	}
406
407	return args.args[0];
408}
409
410/**
411 * knav_dma_open_channel() - try to setup an exclusive slave channel
412 * @dev:	pointer to client device structure
413 * @name:	slave channel name
414 * @config:	dma configuration parameters
415 *
416 * Returns pointer to appropriate DMA channel on success or NULL.
417 */
418void *knav_dma_open_channel(struct device *dev, const char *name,
419					struct knav_dma_cfg *config)
420{
421	struct knav_dma_chan *chan;
422	struct knav_dma_device *dma;
423	bool found = false;
424	int chan_num = -1;
425	const char *instance;
426
427	if (!kdev) {
428		pr_err("keystone-navigator-dma driver not registered\n");
429		return (void *)-EINVAL;
430	}
431
432	chan_num = of_channel_match_helper(dev->of_node, name, &instance);
433	if (chan_num < 0) {
434		dev_err(kdev->dev, "No DMA instace with name %s\n", name);
435		return (void *)-EINVAL;
436	}
437
438	dev_dbg(kdev->dev, "initializing %s channel %d from DMA %s\n",
439		  config->direction == DMA_MEM_TO_DEV   ? "transmit" :
440		  config->direction == DMA_DEV_TO_MEM ? "receive"  :
441		  "unknown", chan_num, instance);
442
443	if (config->direction != DMA_MEM_TO_DEV &&
444	    config->direction != DMA_DEV_TO_MEM) {
445		dev_err(kdev->dev, "bad direction\n");
446		return (void *)-EINVAL;
447	}
448
449	/* Look for correct dma instance */
450	list_for_each_entry(dma, &kdev->list, list) {
451		if (!strcmp(dma->name, instance)) {
452			found = true;
453			break;
454		}
455	}
456	if (!found) {
457		dev_err(kdev->dev, "No DMA instace with name %s\n", instance);
458		return (void *)-EINVAL;
459	}
460
461	/* Look for correct dma channel from dma instance */
462	found = false;
463	list_for_each_entry(chan, &dma->chan_list, list) {
464		if (config->direction == DMA_MEM_TO_DEV) {
465			if (chan->channel == chan_num) {
466				found = true;
467				break;
468			}
469		} else {
470			if (chan->flow == chan_num) {
471				found = true;
472				break;
473			}
474		}
475	}
476	if (!found) {
477		dev_err(kdev->dev, "channel %d is not in DMA %s\n",
478				chan_num, instance);
479		return (void *)-EINVAL;
480	}
481
482	if (atomic_read(&chan->ref_count) >= 1) {
483		if (!check_config(chan, config)) {
484			dev_err(kdev->dev, "channel %d config miss-match\n",
485				chan_num);
486			return (void *)-EINVAL;
487		}
488	}
489
490	if (atomic_inc_return(&chan->dma->ref_count) <= 1)
491		knav_dma_hw_init(chan->dma);
492
493	if (atomic_inc_return(&chan->ref_count) <= 1)
494		chan_start(chan, config);
495
496	dev_dbg(kdev->dev, "channel %d opened from DMA %s\n",
497				chan_num, instance);
498
499	return chan;
500}
501EXPORT_SYMBOL_GPL(knav_dma_open_channel);
502
503/**
504 * knav_dma_close_channel()	- Destroy a dma channel
505 *
506 * channel:	dma channel handle
507 *
508 */
509void knav_dma_close_channel(void *channel)
510{
511	struct knav_dma_chan *chan = channel;
512
513	if (!kdev) {
514		pr_err("keystone-navigator-dma driver not registered\n");
515		return;
516	}
517
518	if (atomic_dec_return(&chan->ref_count) <= 0)
519		chan_stop(chan);
520
521	if (atomic_dec_return(&chan->dma->ref_count) <= 0)
522		knav_dma_hw_destroy(chan->dma);
523
524	dev_dbg(kdev->dev, "channel %d or flow %d closed from DMA %s\n",
525			chan->channel, chan->flow, chan->dma->name);
526}
527EXPORT_SYMBOL_GPL(knav_dma_close_channel);
528
529static void __iomem *pktdma_get_regs(struct knav_dma_device *dma,
530				struct device_node *node,
531				unsigned index, resource_size_t *_size)
532{
533	struct device *dev = kdev->dev;
534	struct resource res;
535	void __iomem *regs;
536	int ret;
537
538	ret = of_address_to_resource(node, index, &res);
539	if (ret) {
540		dev_err(dev, "Can't translate of node(%s) address for index(%d)\n",
541			node->name, index);
542		return ERR_PTR(ret);
543	}
544
545	regs = devm_ioremap_resource(kdev->dev, &res);
546	if (IS_ERR(regs))
547		dev_err(dev, "Failed to map register base for index(%d) node(%s)\n",
548			index, node->name);
549	if (_size)
550		*_size = resource_size(&res);
551
552	return regs;
553}
554
555static int pktdma_init_rx_chan(struct knav_dma_chan *chan, u32 flow)
556{
557	struct knav_dma_device *dma = chan->dma;
558
559	chan->flow = flow;
560	chan->reg_rx_flow = dma->reg_rx_flow + flow;
561	chan->channel = DMA_INVALID_ID;
562	dev_dbg(kdev->dev, "rx flow(%d) (%p)\n", chan->flow, chan->reg_rx_flow);
563
564	return 0;
565}
566
567static int pktdma_init_tx_chan(struct knav_dma_chan *chan, u32 channel)
568{
569	struct knav_dma_device *dma = chan->dma;
570
571	chan->channel = channel;
572	chan->reg_chan = dma->reg_tx_chan + channel;
573	chan->reg_tx_sched = dma->reg_tx_sched + channel;
574	chan->flow = DMA_INVALID_ID;
575	dev_dbg(kdev->dev, "tx channel(%d) (%p)\n", chan->channel, chan->reg_chan);
576
577	return 0;
578}
579
580static int pktdma_init_chan(struct knav_dma_device *dma,
581				enum dma_transfer_direction dir,
582				unsigned chan_num)
583{
584	struct device *dev = kdev->dev;
585	struct knav_dma_chan *chan;
586	int ret = -EINVAL;
587
588	chan = devm_kzalloc(dev, sizeof(*chan), GFP_KERNEL);
589	if (!chan)
590		return -ENOMEM;
591
592	INIT_LIST_HEAD(&chan->list);
593	chan->dma	= dma;
594	chan->direction	= DMA_NONE;
595	atomic_set(&chan->ref_count, 0);
596	spin_lock_init(&chan->lock);
597
598	if (dir == DMA_MEM_TO_DEV) {
599		chan->direction = dir;
600		ret = pktdma_init_tx_chan(chan, chan_num);
601	} else if (dir == DMA_DEV_TO_MEM) {
602		chan->direction = dir;
603		ret = pktdma_init_rx_chan(chan, chan_num);
604	} else {
605		dev_err(dev, "channel(%d) direction unknown\n", chan_num);
606	}
607
608	list_add_tail(&chan->list, &dma->chan_list);
609
610	return ret;
611}
612
613static int dma_init(struct device_node *cloud, struct device_node *dma_node)
614{
615	unsigned max_tx_chan, max_rx_chan, max_rx_flow, max_tx_sched;
616	struct device_node *node = dma_node;
617	struct knav_dma_device *dma;
618	int ret, len, num_chan = 0;
619	resource_size_t size;
620	u32 timeout;
621	u32 i;
622
623	dma = devm_kzalloc(kdev->dev, sizeof(*dma), GFP_KERNEL);
624	if (!dma) {
625		dev_err(kdev->dev, "could not allocate driver mem\n");
626		return -ENOMEM;
627	}
628	INIT_LIST_HEAD(&dma->list);
629	INIT_LIST_HEAD(&dma->chan_list);
630
631	if (!of_find_property(cloud, "ti,navigator-cloud-address", &len)) {
632		dev_err(kdev->dev, "unspecified navigator cloud addresses\n");
633		return -ENODEV;
634	}
635
636	dma->logical_queue_managers = len / sizeof(u32);
637	if (dma->logical_queue_managers > DMA_MAX_QMS) {
638		dev_warn(kdev->dev, "too many queue mgrs(>%d) rest ignored\n",
639			 dma->logical_queue_managers);
640		dma->logical_queue_managers = DMA_MAX_QMS;
641	}
642
643	ret = of_property_read_u32_array(cloud, "ti,navigator-cloud-address",
644					dma->qm_base_address,
645					dma->logical_queue_managers);
646	if (ret) {
647		dev_err(kdev->dev, "invalid navigator cloud addresses\n");
648		return -ENODEV;
649	}
650
651	dma->reg_global	 = pktdma_get_regs(dma, node, 0, &size);
652	if (!dma->reg_global)
653		return -ENODEV;
654	if (size < sizeof(struct reg_global)) {
655		dev_err(kdev->dev, "bad size %pa for global regs\n", &size);
656		return -ENODEV;
657	}
658
659	dma->reg_tx_chan = pktdma_get_regs(dma, node, 1, &size);
660	if (!dma->reg_tx_chan)
661		return -ENODEV;
662
663	max_tx_chan = size / sizeof(struct reg_chan);
664	dma->reg_rx_chan = pktdma_get_regs(dma, node, 2, &size);
665	if (!dma->reg_rx_chan)
666		return -ENODEV;
667
668	max_rx_chan = size / sizeof(struct reg_chan);
669	dma->reg_tx_sched = pktdma_get_regs(dma, node, 3, &size);
670	if (!dma->reg_tx_sched)
671		return -ENODEV;
672
673	max_tx_sched = size / sizeof(struct reg_tx_sched);
674	dma->reg_rx_flow = pktdma_get_regs(dma, node, 4, &size);
675	if (!dma->reg_rx_flow)
676		return -ENODEV;
677
678	max_rx_flow = size / sizeof(struct reg_rx_flow);
679	dma->rx_priority = DMA_PRIO_DEFAULT;
680	dma->tx_priority = DMA_PRIO_DEFAULT;
681
682	dma->enable_all	= (of_get_property(node, "ti,enable-all", NULL) != NULL);
683	dma->loopback	= (of_get_property(node, "ti,loop-back",  NULL) != NULL);
684
685	ret = of_property_read_u32(node, "ti,rx-retry-timeout", &timeout);
686	if (ret < 0) {
687		dev_dbg(kdev->dev, "unspecified rx timeout using value %d\n",
688			DMA_RX_TIMEOUT_DEFAULT);
689		timeout = DMA_RX_TIMEOUT_DEFAULT;
690	}
691
692	dma->rx_timeout = timeout;
693	dma->max_rx_chan = max_rx_chan;
694	dma->max_rx_flow = max_rx_flow;
695	dma->max_tx_chan = min(max_tx_chan, max_tx_sched);
696	atomic_set(&dma->ref_count, 0);
697	strcpy(dma->name, node->name);
698	spin_lock_init(&dma->lock);
699
700	for (i = 0; i < dma->max_tx_chan; i++) {
701		if (pktdma_init_chan(dma, DMA_MEM_TO_DEV, i) >= 0)
702			num_chan++;
703	}
704
705	for (i = 0; i < dma->max_rx_flow; i++) {
706		if (pktdma_init_chan(dma, DMA_DEV_TO_MEM, i) >= 0)
707			num_chan++;
708	}
709
710	list_add_tail(&dma->list, &kdev->list);
711
712	/*
713	 * For DSP software usecases or userpace transport software, setup all
714	 * the DMA hardware resources.
715	 */
716	if (dma->enable_all) {
717		atomic_inc(&dma->ref_count);
718		knav_dma_hw_init(dma);
719		dma_hw_enable_all(dma);
720	}
721
722	dev_info(kdev->dev, "DMA %s registered %d logical channels, flows %d, tx chans: %d, rx chans: %d%s\n",
723		dma->name, num_chan, dma->max_rx_flow,
724		dma->max_tx_chan, dma->max_rx_chan,
725		dma->loopback ? ", loopback" : "");
726
727	return 0;
728}
729
730static int knav_dma_probe(struct platform_device *pdev)
731{
732	struct device *dev = &pdev->dev;
733	struct device_node *node = pdev->dev.of_node;
734	struct device_node *child;
735	int ret = 0;
736
737	if (!node) {
738		dev_err(&pdev->dev, "could not find device info\n");
739		return -EINVAL;
740	}
741
742	kdev = devm_kzalloc(dev,
743			sizeof(struct knav_dma_pool_device), GFP_KERNEL);
744	if (!kdev) {
745		dev_err(dev, "could not allocate driver mem\n");
746		return -ENOMEM;
747	}
748
749	kdev->dev = dev;
750	INIT_LIST_HEAD(&kdev->list);
751
752	pm_runtime_enable(kdev->dev);
753	ret = pm_runtime_get_sync(kdev->dev);
754	if (ret < 0) {
755		dev_err(kdev->dev, "unable to enable pktdma, err %d\n", ret);
756		return ret;
757	}
758
759	/* Initialise all packet dmas */
760	for_each_child_of_node(node, child) {
761		ret = dma_init(node, child);
762		if (ret) {
763			dev_err(&pdev->dev, "init failed with %d\n", ret);
764			break;
765		}
766	}
767
768	if (list_empty(&kdev->list)) {
769		dev_err(dev, "no valid dma instance\n");
770		return -ENODEV;
771	}
772
773	debugfs_create_file("knav_dma", S_IFREG | S_IRUGO, NULL, NULL,
774			    &knav_dma_debug_ops);
775
776	return ret;
777}
778
779static int knav_dma_remove(struct platform_device *pdev)
780{
781	struct knav_dma_device *dma;
782
783	list_for_each_entry(dma, &kdev->list, list) {
784		if (atomic_dec_return(&dma->ref_count) == 0)
785			knav_dma_hw_destroy(dma);
786	}
787
788	pm_runtime_put_sync(&pdev->dev);
789	pm_runtime_disable(&pdev->dev);
790
791	return 0;
792}
793
794static struct of_device_id of_match[] = {
795	{ .compatible = "ti,keystone-navigator-dma", },
796	{},
797};
798
799MODULE_DEVICE_TABLE(of, of_match);
800
801static struct platform_driver knav_dma_driver = {
802	.probe	= knav_dma_probe,
803	.remove	= knav_dma_remove,
804	.driver = {
805		.name		= "keystone-navigator-dma",
806		.of_match_table	= of_match,
807	},
808};
809module_platform_driver(knav_dma_driver);
810
811MODULE_LICENSE("GPL v2");
812MODULE_DESCRIPTION("TI Keystone Navigator Packet DMA driver");
813MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com>");
814MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");
815