xref: /openbmc/linux/drivers/soc/ti/knav_dma.c (revision 4f6cce39)
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 
65 struct 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 
73 struct reg_chan {
74 	u32	control;
75 	u32	mode;
76 	u32	__rsvd[6];
77 };
78 
79 struct reg_tx_sched {
80 	u32	prio;
81 };
82 
83 struct reg_rx_flow {
84 	u32	control;
85 	u32	tags;
86 	u32	tag_sel;
87 	u32	fdq_sel[2];
88 	u32	thresh[3];
89 };
90 
91 struct knav_dma_pool_device {
92 	struct device			*dev;
93 	struct list_head		list;
94 };
95 
96 struct 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 
115 struct 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 
135 static struct knav_dma_pool_device *kdev;
136 
137 static 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 
145 static 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 
203 static 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 
229 static 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 
257 static 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 
268 static 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 
296 static 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 
312 static 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 
340 static 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 
351 static 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 
366 static int knav_dma_debug_open(struct inode *inode, struct file *file)
367 {
368 	return single_open(file, dma_debug_show, NULL);
369 }
370 
371 static 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 
378 static 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' property\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 phandle 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  */
418 void *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 }
501 EXPORT_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  */
509 void 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 }
527 EXPORT_SYMBOL_GPL(knav_dma_close_channel);
528 
529 static 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 
555 static 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 
567 static 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 
580 static 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 
613 static 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 
730 static 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 
779 static 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 
794 static struct of_device_id of_match[] = {
795 	{ .compatible = "ti,keystone-navigator-dma", },
796 	{},
797 };
798 
799 MODULE_DEVICE_TABLE(of, of_match);
800 
801 static 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 };
809 module_platform_driver(knav_dma_driver);
810 
811 MODULE_LICENSE("GPL v2");
812 MODULE_DESCRIPTION("TI Keystone Navigator Packet DMA driver");
813 MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com>");
814 MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");
815