xref: /openbmc/linux/drivers/soc/ti/knav_dma.c (revision 2fa5ebe3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 Texas Instruments Incorporated
4  * Authors:	Santosh Shilimkar <santosh.shilimkar@ti.com>
5  *		Sandeep Nair <sandeep_n@ti.com>
6  *		Cyril Chemparathy <cyril@ti.com>
7  */
8 
9 #include <linux/io.h>
10 #include <linux/sched.h>
11 #include <linux/module.h>
12 #include <linux/dma-direction.h>
13 #include <linux/interrupt.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/of_dma.h>
16 #include <linux/of_address.h>
17 #include <linux/platform_device.h>
18 #include <linux/soc/ti/knav_dma.h>
19 #include <linux/debugfs.h>
20 #include <linux/seq_file.h>
21 
22 #define REG_MASK		0xffffffff
23 
24 #define DMA_LOOPBACK		BIT(31)
25 #define DMA_ENABLE		BIT(31)
26 #define DMA_TEARDOWN		BIT(30)
27 
28 #define DMA_TX_FILT_PSWORDS	BIT(29)
29 #define DMA_TX_FILT_EINFO	BIT(30)
30 #define DMA_TX_PRIO_SHIFT	0
31 #define DMA_RX_PRIO_SHIFT	16
32 #define DMA_PRIO_MASK		GENMASK(3, 0)
33 #define DMA_PRIO_DEFAULT	0
34 #define DMA_RX_TIMEOUT_DEFAULT	17500 /* cycles */
35 #define DMA_RX_TIMEOUT_MASK	GENMASK(16, 0)
36 #define DMA_RX_TIMEOUT_SHIFT	0
37 
38 #define CHAN_HAS_EPIB		BIT(30)
39 #define CHAN_HAS_PSINFO		BIT(29)
40 #define CHAN_ERR_RETRY		BIT(28)
41 #define CHAN_PSINFO_AT_SOP	BIT(25)
42 #define CHAN_SOP_OFF_SHIFT	16
43 #define CHAN_SOP_OFF_MASK	GENMASK(9, 0)
44 #define DESC_TYPE_SHIFT		26
45 #define DESC_TYPE_MASK		GENMASK(2, 0)
46 
47 /*
48  * QMGR & QNUM together make up 14 bits with QMGR as the 2 MSb's in the logical
49  * navigator cloud mapping scheme.
50  * using the 14bit physical queue numbers directly maps into this scheme.
51  */
52 #define CHAN_QNUM_MASK		GENMASK(14, 0)
53 #define DMA_MAX_QMS		4
54 #define DMA_TIMEOUT		1	/* msecs */
55 #define DMA_INVALID_ID		0xffff
56 
57 struct reg_global {
58 	u32	revision;
59 	u32	perf_control;
60 	u32	emulation_control;
61 	u32	priority_control;
62 	u32	qm_base_address[DMA_MAX_QMS];
63 };
64 
65 struct reg_chan {
66 	u32	control;
67 	u32	mode;
68 	u32	__rsvd[6];
69 };
70 
71 struct reg_tx_sched {
72 	u32	prio;
73 };
74 
75 struct reg_rx_flow {
76 	u32	control;
77 	u32	tags;
78 	u32	tag_sel;
79 	u32	fdq_sel[2];
80 	u32	thresh[3];
81 };
82 
83 struct knav_dma_pool_device {
84 	struct device			*dev;
85 	struct list_head		list;
86 };
87 
88 struct knav_dma_device {
89 	bool				loopback, enable_all;
90 	unsigned			tx_priority, rx_priority, rx_timeout;
91 	unsigned			logical_queue_managers;
92 	unsigned			qm_base_address[DMA_MAX_QMS];
93 	struct reg_global __iomem	*reg_global;
94 	struct reg_chan __iomem		*reg_tx_chan;
95 	struct reg_rx_flow __iomem	*reg_rx_flow;
96 	struct reg_chan __iomem		*reg_rx_chan;
97 	struct reg_tx_sched __iomem	*reg_tx_sched;
98 	unsigned			max_rx_chan, max_tx_chan;
99 	unsigned			max_rx_flow;
100 	char				name[32];
101 	atomic_t			ref_count;
102 	struct list_head		list;
103 	struct list_head		chan_list;
104 	spinlock_t			lock;
105 };
106 
107 struct knav_dma_chan {
108 	enum dma_transfer_direction	direction;
109 	struct knav_dma_device		*dma;
110 	atomic_t			ref_count;
111 
112 	/* registers */
113 	struct reg_chan __iomem		*reg_chan;
114 	struct reg_tx_sched __iomem	*reg_tx_sched;
115 	struct reg_rx_flow __iomem	*reg_rx_flow;
116 
117 	/* configuration stuff */
118 	unsigned			channel, flow;
119 	struct knav_dma_cfg		cfg;
120 	struct list_head		list;
121 	spinlock_t			lock;
122 };
123 
124 #define chan_number(ch)	((ch->direction == DMA_MEM_TO_DEV) ? \
125 			ch->channel : ch->flow)
126 
127 static struct knav_dma_pool_device *kdev;
128 
129 static bool device_ready;
130 bool knav_dma_device_ready(void)
131 {
132 	return device_ready;
133 }
134 EXPORT_SYMBOL_GPL(knav_dma_device_ready);
135 
136 static bool check_config(struct knav_dma_chan *chan, struct knav_dma_cfg *cfg)
137 {
138 	if (!memcmp(&chan->cfg, cfg, sizeof(*cfg)))
139 		return true;
140 	else
141 		return false;
142 }
143 
144 static int chan_start(struct knav_dma_chan *chan,
145 			struct knav_dma_cfg *cfg)
146 {
147 	u32 v = 0;
148 
149 	spin_lock(&chan->lock);
150 	if ((chan->direction == DMA_MEM_TO_DEV) && chan->reg_chan) {
151 		if (cfg->u.tx.filt_pswords)
152 			v |= DMA_TX_FILT_PSWORDS;
153 		if (cfg->u.tx.filt_einfo)
154 			v |= DMA_TX_FILT_EINFO;
155 		writel_relaxed(v, &chan->reg_chan->mode);
156 		writel_relaxed(DMA_ENABLE, &chan->reg_chan->control);
157 	}
158 
159 	if (chan->reg_tx_sched)
160 		writel_relaxed(cfg->u.tx.priority, &chan->reg_tx_sched->prio);
161 
162 	if (chan->reg_rx_flow) {
163 		v = 0;
164 
165 		if (cfg->u.rx.einfo_present)
166 			v |= CHAN_HAS_EPIB;
167 		if (cfg->u.rx.psinfo_present)
168 			v |= CHAN_HAS_PSINFO;
169 		if (cfg->u.rx.err_mode == DMA_RETRY)
170 			v |= CHAN_ERR_RETRY;
171 		v |= (cfg->u.rx.desc_type & DESC_TYPE_MASK) << DESC_TYPE_SHIFT;
172 		if (cfg->u.rx.psinfo_at_sop)
173 			v |= CHAN_PSINFO_AT_SOP;
174 		v |= (cfg->u.rx.sop_offset & CHAN_SOP_OFF_MASK)
175 			<< CHAN_SOP_OFF_SHIFT;
176 		v |= cfg->u.rx.dst_q & CHAN_QNUM_MASK;
177 
178 		writel_relaxed(v, &chan->reg_rx_flow->control);
179 		writel_relaxed(0, &chan->reg_rx_flow->tags);
180 		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
181 
182 		v =  cfg->u.rx.fdq[0] << 16;
183 		v |=  cfg->u.rx.fdq[1] & CHAN_QNUM_MASK;
184 		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[0]);
185 
186 		v =  cfg->u.rx.fdq[2] << 16;
187 		v |=  cfg->u.rx.fdq[3] & CHAN_QNUM_MASK;
188 		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[1]);
189 
190 		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
191 		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
192 		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
193 	}
194 
195 	/* Keep a copy of the cfg */
196 	memcpy(&chan->cfg, cfg, sizeof(*cfg));
197 	spin_unlock(&chan->lock);
198 
199 	return 0;
200 }
201 
202 static int chan_teardown(struct knav_dma_chan *chan)
203 {
204 	unsigned long end, value;
205 
206 	if (!chan->reg_chan)
207 		return 0;
208 
209 	/* indicate teardown */
210 	writel_relaxed(DMA_TEARDOWN, &chan->reg_chan->control);
211 
212 	/* wait for the dma to shut itself down */
213 	end = jiffies + msecs_to_jiffies(DMA_TIMEOUT);
214 	do {
215 		value = readl_relaxed(&chan->reg_chan->control);
216 		if ((value & DMA_ENABLE) == 0)
217 			break;
218 	} while (time_after(end, jiffies));
219 
220 	if (readl_relaxed(&chan->reg_chan->control) & DMA_ENABLE) {
221 		dev_err(kdev->dev, "timeout waiting for teardown\n");
222 		return -ETIMEDOUT;
223 	}
224 
225 	return 0;
226 }
227 
228 static void chan_stop(struct knav_dma_chan *chan)
229 {
230 	spin_lock(&chan->lock);
231 	if (chan->reg_rx_flow) {
232 		/* first detach fdqs, starve out the flow */
233 		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[0]);
234 		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[1]);
235 		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
236 		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
237 		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
238 	}
239 
240 	/* teardown the dma channel */
241 	chan_teardown(chan);
242 
243 	/* then disconnect the completion side */
244 	if (chan->reg_rx_flow) {
245 		writel_relaxed(0, &chan->reg_rx_flow->control);
246 		writel_relaxed(0, &chan->reg_rx_flow->tags);
247 		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
248 	}
249 
250 	memset(&chan->cfg, 0, sizeof(struct knav_dma_cfg));
251 	spin_unlock(&chan->lock);
252 
253 	dev_dbg(kdev->dev, "channel stopped\n");
254 }
255 
256 static void dma_hw_enable_all(struct knav_dma_device *dma)
257 {
258 	int i;
259 
260 	for (i = 0; i < dma->max_tx_chan; i++) {
261 		writel_relaxed(0, &dma->reg_tx_chan[i].mode);
262 		writel_relaxed(DMA_ENABLE, &dma->reg_tx_chan[i].control);
263 	}
264 }
265 
266 
267 static void knav_dma_hw_init(struct knav_dma_device *dma)
268 {
269 	unsigned v;
270 	int i;
271 
272 	spin_lock(&dma->lock);
273 	v  = dma->loopback ? DMA_LOOPBACK : 0;
274 	writel_relaxed(v, &dma->reg_global->emulation_control);
275 
276 	v = readl_relaxed(&dma->reg_global->perf_control);
277 	v |= ((dma->rx_timeout & DMA_RX_TIMEOUT_MASK) << DMA_RX_TIMEOUT_SHIFT);
278 	writel_relaxed(v, &dma->reg_global->perf_control);
279 
280 	v = ((dma->tx_priority << DMA_TX_PRIO_SHIFT) |
281 	     (dma->rx_priority << DMA_RX_PRIO_SHIFT));
282 
283 	writel_relaxed(v, &dma->reg_global->priority_control);
284 
285 	/* Always enable all Rx channels. Rx paths are managed using flows */
286 	for (i = 0; i < dma->max_rx_chan; i++)
287 		writel_relaxed(DMA_ENABLE, &dma->reg_rx_chan[i].control);
288 
289 	for (i = 0; i < dma->logical_queue_managers; i++)
290 		writel_relaxed(dma->qm_base_address[i],
291 			       &dma->reg_global->qm_base_address[i]);
292 	spin_unlock(&dma->lock);
293 }
294 
295 static void knav_dma_hw_destroy(struct knav_dma_device *dma)
296 {
297 	int i;
298 	unsigned v;
299 
300 	spin_lock(&dma->lock);
301 	v = ~DMA_ENABLE & REG_MASK;
302 
303 	for (i = 0; i < dma->max_rx_chan; i++)
304 		writel_relaxed(v, &dma->reg_rx_chan[i].control);
305 
306 	for (i = 0; i < dma->max_tx_chan; i++)
307 		writel_relaxed(v, &dma->reg_tx_chan[i].control);
308 	spin_unlock(&dma->lock);
309 }
310 
311 static void dma_debug_show_channels(struct seq_file *s,
312 					struct knav_dma_chan *chan)
313 {
314 	int i;
315 
316 	seq_printf(s, "\t%s %d:\t",
317 		((chan->direction == DMA_MEM_TO_DEV) ? "tx chan" : "rx flow"),
318 		chan_number(chan));
319 
320 	if (chan->direction == DMA_MEM_TO_DEV) {
321 		seq_printf(s, "einfo - %d, pswords - %d, priority - %d\n",
322 			chan->cfg.u.tx.filt_einfo,
323 			chan->cfg.u.tx.filt_pswords,
324 			chan->cfg.u.tx.priority);
325 	} else {
326 		seq_printf(s, "einfo - %d, psinfo - %d, desc_type - %d\n",
327 			chan->cfg.u.rx.einfo_present,
328 			chan->cfg.u.rx.psinfo_present,
329 			chan->cfg.u.rx.desc_type);
330 		seq_printf(s, "\t\t\tdst_q: [%d], thresh: %d fdq: ",
331 			chan->cfg.u.rx.dst_q,
332 			chan->cfg.u.rx.thresh);
333 		for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN; i++)
334 			seq_printf(s, "[%d]", chan->cfg.u.rx.fdq[i]);
335 		seq_printf(s, "\n");
336 	}
337 }
338 
339 static void dma_debug_show_devices(struct seq_file *s,
340 					struct knav_dma_device *dma)
341 {
342 	struct knav_dma_chan *chan;
343 
344 	list_for_each_entry(chan, &dma->chan_list, list) {
345 		if (atomic_read(&chan->ref_count))
346 			dma_debug_show_channels(s, chan);
347 	}
348 }
349 
350 static int knav_dma_debug_show(struct seq_file *s, void *v)
351 {
352 	struct knav_dma_device *dma;
353 
354 	list_for_each_entry(dma, &kdev->list, list) {
355 		if (atomic_read(&dma->ref_count)) {
356 			seq_printf(s, "%s : max_tx_chan: (%d), max_rx_flows: (%d)\n",
357 			dma->name, dma->max_tx_chan, dma->max_rx_flow);
358 			dma_debug_show_devices(s, dma);
359 		}
360 	}
361 
362 	return 0;
363 }
364 
365 DEFINE_SHOW_ATTRIBUTE(knav_dma_debug);
366 
367 static int of_channel_match_helper(struct device_node *np, const char *name,
368 					const char **dma_instance)
369 {
370 	struct of_phandle_args args;
371 	struct device_node *dma_node;
372 	int index;
373 
374 	dma_node = of_parse_phandle(np, "ti,navigator-dmas", 0);
375 	if (!dma_node)
376 		return -ENODEV;
377 
378 	*dma_instance = dma_node->name;
379 	index = of_property_match_string(np, "ti,navigator-dma-names", name);
380 	if (index < 0) {
381 		dev_err(kdev->dev, "No 'ti,navigator-dma-names' property\n");
382 		return -ENODEV;
383 	}
384 
385 	if (of_parse_phandle_with_fixed_args(np, "ti,navigator-dmas",
386 					1, index, &args)) {
387 		dev_err(kdev->dev, "Missing the phandle args name %s\n", name);
388 		return -ENODEV;
389 	}
390 
391 	if (args.args[0] < 0) {
392 		dev_err(kdev->dev, "Missing args for %s\n", name);
393 		return -ENODEV;
394 	}
395 
396 	return args.args[0];
397 }
398 
399 /**
400  * knav_dma_open_channel() - try to setup an exclusive slave channel
401  * @dev:	pointer to client device structure
402  * @name:	slave channel name
403  * @config:	dma configuration parameters
404  *
405  * Returns pointer to appropriate DMA channel on success or error.
406  */
407 void *knav_dma_open_channel(struct device *dev, const char *name,
408 					struct knav_dma_cfg *config)
409 {
410 	struct knav_dma_device *dma = NULL, *iter1;
411 	struct knav_dma_chan *chan = NULL, *iter2;
412 	int chan_num = -1;
413 	const char *instance;
414 
415 	if (!kdev) {
416 		pr_err("keystone-navigator-dma driver not registered\n");
417 		return (void *)-EINVAL;
418 	}
419 
420 	chan_num = of_channel_match_helper(dev->of_node, name, &instance);
421 	if (chan_num < 0) {
422 		dev_err(kdev->dev, "No DMA instance with name %s\n", name);
423 		return (void *)-EINVAL;
424 	}
425 
426 	dev_dbg(kdev->dev, "initializing %s channel %d from DMA %s\n",
427 		  config->direction == DMA_MEM_TO_DEV ? "transmit" :
428 		  config->direction == DMA_DEV_TO_MEM ? "receive"  :
429 		  "unknown", chan_num, instance);
430 
431 	if (config->direction != DMA_MEM_TO_DEV &&
432 	    config->direction != DMA_DEV_TO_MEM) {
433 		dev_err(kdev->dev, "bad direction\n");
434 		return (void *)-EINVAL;
435 	}
436 
437 	/* Look for correct dma instance */
438 	list_for_each_entry(iter1, &kdev->list, list) {
439 		if (!strcmp(iter1->name, instance)) {
440 			dma = iter1;
441 			break;
442 		}
443 	}
444 	if (!dma) {
445 		dev_err(kdev->dev, "No DMA instance with name %s\n", instance);
446 		return (void *)-EINVAL;
447 	}
448 
449 	/* Look for correct dma channel from dma instance */
450 	list_for_each_entry(iter2, &dma->chan_list, list) {
451 		if (config->direction == DMA_MEM_TO_DEV) {
452 			if (iter2->channel == chan_num) {
453 				chan = iter2;
454 				break;
455 			}
456 		} else {
457 			if (iter2->flow == chan_num) {
458 				chan = iter2;
459 				break;
460 			}
461 		}
462 	}
463 	if (!chan) {
464 		dev_err(kdev->dev, "channel %d is not in DMA %s\n",
465 				chan_num, instance);
466 		return (void *)-EINVAL;
467 	}
468 
469 	if (atomic_read(&chan->ref_count) >= 1) {
470 		if (!check_config(chan, config)) {
471 			dev_err(kdev->dev, "channel %d config miss-match\n",
472 				chan_num);
473 			return (void *)-EINVAL;
474 		}
475 	}
476 
477 	if (atomic_inc_return(&chan->dma->ref_count) <= 1)
478 		knav_dma_hw_init(chan->dma);
479 
480 	if (atomic_inc_return(&chan->ref_count) <= 1)
481 		chan_start(chan, config);
482 
483 	dev_dbg(kdev->dev, "channel %d opened from DMA %s\n",
484 				chan_num, instance);
485 
486 	return chan;
487 }
488 EXPORT_SYMBOL_GPL(knav_dma_open_channel);
489 
490 /**
491  * knav_dma_close_channel()	- Destroy a dma channel
492  *
493  * @channel:	dma channel handle
494  *
495  */
496 void knav_dma_close_channel(void *channel)
497 {
498 	struct knav_dma_chan *chan = channel;
499 
500 	if (!kdev) {
501 		pr_err("keystone-navigator-dma driver not registered\n");
502 		return;
503 	}
504 
505 	if (atomic_dec_return(&chan->ref_count) <= 0)
506 		chan_stop(chan);
507 
508 	if (atomic_dec_return(&chan->dma->ref_count) <= 0)
509 		knav_dma_hw_destroy(chan->dma);
510 
511 	dev_dbg(kdev->dev, "channel %d or flow %d closed from DMA %s\n",
512 			chan->channel, chan->flow, chan->dma->name);
513 }
514 EXPORT_SYMBOL_GPL(knav_dma_close_channel);
515 
516 static void __iomem *pktdma_get_regs(struct knav_dma_device *dma,
517 				struct device_node *node,
518 				unsigned index, resource_size_t *_size)
519 {
520 	struct device *dev = kdev->dev;
521 	struct resource res;
522 	void __iomem *regs;
523 	int ret;
524 
525 	ret = of_address_to_resource(node, index, &res);
526 	if (ret) {
527 		dev_err(dev, "Can't translate of node(%pOFn) address for index(%d)\n",
528 			node, index);
529 		return ERR_PTR(ret);
530 	}
531 
532 	regs = devm_ioremap_resource(kdev->dev, &res);
533 	if (IS_ERR(regs))
534 		dev_err(dev, "Failed to map register base for index(%d) node(%pOFn)\n",
535 			index, node);
536 	if (_size)
537 		*_size = resource_size(&res);
538 
539 	return regs;
540 }
541 
542 static int pktdma_init_rx_chan(struct knav_dma_chan *chan, u32 flow)
543 {
544 	struct knav_dma_device *dma = chan->dma;
545 
546 	chan->flow = flow;
547 	chan->reg_rx_flow = dma->reg_rx_flow + flow;
548 	chan->channel = DMA_INVALID_ID;
549 	dev_dbg(kdev->dev, "rx flow(%d) (%p)\n", chan->flow, chan->reg_rx_flow);
550 
551 	return 0;
552 }
553 
554 static int pktdma_init_tx_chan(struct knav_dma_chan *chan, u32 channel)
555 {
556 	struct knav_dma_device *dma = chan->dma;
557 
558 	chan->channel = channel;
559 	chan->reg_chan = dma->reg_tx_chan + channel;
560 	chan->reg_tx_sched = dma->reg_tx_sched + channel;
561 	chan->flow = DMA_INVALID_ID;
562 	dev_dbg(kdev->dev, "tx channel(%d) (%p)\n", chan->channel, chan->reg_chan);
563 
564 	return 0;
565 }
566 
567 static int pktdma_init_chan(struct knav_dma_device *dma,
568 				enum dma_transfer_direction dir,
569 				unsigned chan_num)
570 {
571 	struct device *dev = kdev->dev;
572 	struct knav_dma_chan *chan;
573 	int ret = -EINVAL;
574 
575 	chan = devm_kzalloc(dev, sizeof(*chan), GFP_KERNEL);
576 	if (!chan)
577 		return -ENOMEM;
578 
579 	INIT_LIST_HEAD(&chan->list);
580 	chan->dma	= dma;
581 	chan->direction	= DMA_TRANS_NONE;
582 	atomic_set(&chan->ref_count, 0);
583 	spin_lock_init(&chan->lock);
584 
585 	if (dir == DMA_MEM_TO_DEV) {
586 		chan->direction = dir;
587 		ret = pktdma_init_tx_chan(chan, chan_num);
588 	} else if (dir == DMA_DEV_TO_MEM) {
589 		chan->direction = dir;
590 		ret = pktdma_init_rx_chan(chan, chan_num);
591 	} else {
592 		dev_err(dev, "channel(%d) direction unknown\n", chan_num);
593 	}
594 
595 	list_add_tail(&chan->list, &dma->chan_list);
596 
597 	return ret;
598 }
599 
600 static int dma_init(struct device_node *cloud, struct device_node *dma_node)
601 {
602 	unsigned max_tx_chan, max_rx_chan, max_rx_flow, max_tx_sched;
603 	struct device_node *node = dma_node;
604 	struct knav_dma_device *dma;
605 	int ret, len, num_chan = 0;
606 	resource_size_t size;
607 	u32 timeout;
608 	u32 i;
609 
610 	dma = devm_kzalloc(kdev->dev, sizeof(*dma), GFP_KERNEL);
611 	if (!dma) {
612 		dev_err(kdev->dev, "could not allocate driver mem\n");
613 		return -ENOMEM;
614 	}
615 	INIT_LIST_HEAD(&dma->list);
616 	INIT_LIST_HEAD(&dma->chan_list);
617 
618 	if (!of_find_property(cloud, "ti,navigator-cloud-address", &len)) {
619 		dev_err(kdev->dev, "unspecified navigator cloud addresses\n");
620 		return -ENODEV;
621 	}
622 
623 	dma->logical_queue_managers = len / sizeof(u32);
624 	if (dma->logical_queue_managers > DMA_MAX_QMS) {
625 		dev_warn(kdev->dev, "too many queue mgrs(>%d) rest ignored\n",
626 			 dma->logical_queue_managers);
627 		dma->logical_queue_managers = DMA_MAX_QMS;
628 	}
629 
630 	ret = of_property_read_u32_array(cloud, "ti,navigator-cloud-address",
631 					dma->qm_base_address,
632 					dma->logical_queue_managers);
633 	if (ret) {
634 		dev_err(kdev->dev, "invalid navigator cloud addresses\n");
635 		return -ENODEV;
636 	}
637 
638 	dma->reg_global	 = pktdma_get_regs(dma, node, 0, &size);
639 	if (IS_ERR(dma->reg_global))
640 		return PTR_ERR(dma->reg_global);
641 	if (size < sizeof(struct reg_global)) {
642 		dev_err(kdev->dev, "bad size %pa for global regs\n", &size);
643 		return -ENODEV;
644 	}
645 
646 	dma->reg_tx_chan = pktdma_get_regs(dma, node, 1, &size);
647 	if (IS_ERR(dma->reg_tx_chan))
648 		return PTR_ERR(dma->reg_tx_chan);
649 
650 	max_tx_chan = size / sizeof(struct reg_chan);
651 	dma->reg_rx_chan = pktdma_get_regs(dma, node, 2, &size);
652 	if (IS_ERR(dma->reg_rx_chan))
653 		return PTR_ERR(dma->reg_rx_chan);
654 
655 	max_rx_chan = size / sizeof(struct reg_chan);
656 	dma->reg_tx_sched = pktdma_get_regs(dma, node, 3, &size);
657 	if (IS_ERR(dma->reg_tx_sched))
658 		return PTR_ERR(dma->reg_tx_sched);
659 
660 	max_tx_sched = size / sizeof(struct reg_tx_sched);
661 	dma->reg_rx_flow = pktdma_get_regs(dma, node, 4, &size);
662 	if (IS_ERR(dma->reg_rx_flow))
663 		return PTR_ERR(dma->reg_rx_flow);
664 
665 	max_rx_flow = size / sizeof(struct reg_rx_flow);
666 	dma->rx_priority = DMA_PRIO_DEFAULT;
667 	dma->tx_priority = DMA_PRIO_DEFAULT;
668 
669 	dma->enable_all	= (of_get_property(node, "ti,enable-all", NULL) != NULL);
670 	dma->loopback	= (of_get_property(node, "ti,loop-back",  NULL) != NULL);
671 
672 	ret = of_property_read_u32(node, "ti,rx-retry-timeout", &timeout);
673 	if (ret < 0) {
674 		dev_dbg(kdev->dev, "unspecified rx timeout using value %d\n",
675 			DMA_RX_TIMEOUT_DEFAULT);
676 		timeout = DMA_RX_TIMEOUT_DEFAULT;
677 	}
678 
679 	dma->rx_timeout = timeout;
680 	dma->max_rx_chan = max_rx_chan;
681 	dma->max_rx_flow = max_rx_flow;
682 	dma->max_tx_chan = min(max_tx_chan, max_tx_sched);
683 	atomic_set(&dma->ref_count, 0);
684 	strcpy(dma->name, node->name);
685 	spin_lock_init(&dma->lock);
686 
687 	for (i = 0; i < dma->max_tx_chan; i++) {
688 		if (pktdma_init_chan(dma, DMA_MEM_TO_DEV, i) >= 0)
689 			num_chan++;
690 	}
691 
692 	for (i = 0; i < dma->max_rx_flow; i++) {
693 		if (pktdma_init_chan(dma, DMA_DEV_TO_MEM, i) >= 0)
694 			num_chan++;
695 	}
696 
697 	list_add_tail(&dma->list, &kdev->list);
698 
699 	/*
700 	 * For DSP software usecases or userpace transport software, setup all
701 	 * the DMA hardware resources.
702 	 */
703 	if (dma->enable_all) {
704 		atomic_inc(&dma->ref_count);
705 		knav_dma_hw_init(dma);
706 		dma_hw_enable_all(dma);
707 	}
708 
709 	dev_info(kdev->dev, "DMA %s registered %d logical channels, flows %d, tx chans: %d, rx chans: %d%s\n",
710 		dma->name, num_chan, dma->max_rx_flow,
711 		dma->max_tx_chan, dma->max_rx_chan,
712 		dma->loopback ? ", loopback" : "");
713 
714 	return 0;
715 }
716 
717 static int knav_dma_probe(struct platform_device *pdev)
718 {
719 	struct device *dev = &pdev->dev;
720 	struct device_node *node = pdev->dev.of_node;
721 	struct device_node *child;
722 	int ret = 0;
723 
724 	if (!node) {
725 		dev_err(&pdev->dev, "could not find device info\n");
726 		return -EINVAL;
727 	}
728 
729 	kdev = devm_kzalloc(dev,
730 			sizeof(struct knav_dma_pool_device), GFP_KERNEL);
731 	if (!kdev) {
732 		dev_err(dev, "could not allocate driver mem\n");
733 		return -ENOMEM;
734 	}
735 
736 	kdev->dev = dev;
737 	INIT_LIST_HEAD(&kdev->list);
738 
739 	pm_runtime_enable(kdev->dev);
740 	ret = pm_runtime_resume_and_get(kdev->dev);
741 	if (ret < 0) {
742 		dev_err(kdev->dev, "unable to enable pktdma, err %d\n", ret);
743 		goto err_pm_disable;
744 	}
745 
746 	/* Initialise all packet dmas */
747 	for_each_child_of_node(node, child) {
748 		ret = dma_init(node, child);
749 		if (ret) {
750 			of_node_put(child);
751 			dev_err(&pdev->dev, "init failed with %d\n", ret);
752 			break;
753 		}
754 	}
755 
756 	if (list_empty(&kdev->list)) {
757 		dev_err(dev, "no valid dma instance\n");
758 		ret = -ENODEV;
759 		goto err_put_sync;
760 	}
761 
762 	debugfs_create_file("knav_dma", S_IFREG | S_IRUGO, NULL, NULL,
763 			    &knav_dma_debug_fops);
764 
765 	device_ready = true;
766 	return ret;
767 
768 err_put_sync:
769 	pm_runtime_put_sync(kdev->dev);
770 err_pm_disable:
771 	pm_runtime_disable(kdev->dev);
772 
773 	return ret;
774 }
775 
776 static int knav_dma_remove(struct platform_device *pdev)
777 {
778 	struct knav_dma_device *dma;
779 
780 	list_for_each_entry(dma, &kdev->list, list) {
781 		if (atomic_dec_return(&dma->ref_count) == 0)
782 			knav_dma_hw_destroy(dma);
783 	}
784 
785 	pm_runtime_put_sync(&pdev->dev);
786 	pm_runtime_disable(&pdev->dev);
787 
788 	return 0;
789 }
790 
791 static struct of_device_id of_match[] = {
792 	{ .compatible = "ti,keystone-navigator-dma", },
793 	{},
794 };
795 
796 MODULE_DEVICE_TABLE(of, of_match);
797 
798 static struct platform_driver knav_dma_driver = {
799 	.probe	= knav_dma_probe,
800 	.remove	= knav_dma_remove,
801 	.driver = {
802 		.name		= "keystone-navigator-dma",
803 		.of_match_table	= of_match,
804 	},
805 };
806 module_platform_driver(knav_dma_driver);
807 
808 MODULE_LICENSE("GPL v2");
809 MODULE_DESCRIPTION("TI Keystone Navigator Packet DMA driver");
810 MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com>");
811 MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");
812