xref: /linux/drivers/soc/ti/knav_dma.c (revision 8eecf1c9929aef24e9e75280a39ed1ba3c64fb71)
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 device_ready;
138 bool knav_dma_device_ready(void)
139 {
140 	return device_ready;
141 }
142 EXPORT_SYMBOL_GPL(knav_dma_device_ready);
143 
144 static bool check_config(struct knav_dma_chan *chan, struct knav_dma_cfg *cfg)
145 {
146 	if (!memcmp(&chan->cfg, cfg, sizeof(*cfg)))
147 		return true;
148 	else
149 		return false;
150 }
151 
152 static int chan_start(struct knav_dma_chan *chan,
153 			struct knav_dma_cfg *cfg)
154 {
155 	u32 v = 0;
156 
157 	spin_lock(&chan->lock);
158 	if ((chan->direction == DMA_MEM_TO_DEV) && chan->reg_chan) {
159 		if (cfg->u.tx.filt_pswords)
160 			v |= DMA_TX_FILT_PSWORDS;
161 		if (cfg->u.tx.filt_einfo)
162 			v |= DMA_TX_FILT_EINFO;
163 		writel_relaxed(v, &chan->reg_chan->mode);
164 		writel_relaxed(DMA_ENABLE, &chan->reg_chan->control);
165 	}
166 
167 	if (chan->reg_tx_sched)
168 		writel_relaxed(cfg->u.tx.priority, &chan->reg_tx_sched->prio);
169 
170 	if (chan->reg_rx_flow) {
171 		v = 0;
172 
173 		if (cfg->u.rx.einfo_present)
174 			v |= CHAN_HAS_EPIB;
175 		if (cfg->u.rx.psinfo_present)
176 			v |= CHAN_HAS_PSINFO;
177 		if (cfg->u.rx.err_mode == DMA_RETRY)
178 			v |= CHAN_ERR_RETRY;
179 		v |= (cfg->u.rx.desc_type & DESC_TYPE_MASK) << DESC_TYPE_SHIFT;
180 		if (cfg->u.rx.psinfo_at_sop)
181 			v |= CHAN_PSINFO_AT_SOP;
182 		v |= (cfg->u.rx.sop_offset & CHAN_SOP_OFF_MASK)
183 			<< CHAN_SOP_OFF_SHIFT;
184 		v |= cfg->u.rx.dst_q & CHAN_QNUM_MASK;
185 
186 		writel_relaxed(v, &chan->reg_rx_flow->control);
187 		writel_relaxed(0, &chan->reg_rx_flow->tags);
188 		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
189 
190 		v =  cfg->u.rx.fdq[0] << 16;
191 		v |=  cfg->u.rx.fdq[1] & CHAN_QNUM_MASK;
192 		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[0]);
193 
194 		v =  cfg->u.rx.fdq[2] << 16;
195 		v |=  cfg->u.rx.fdq[3] & CHAN_QNUM_MASK;
196 		writel_relaxed(v, &chan->reg_rx_flow->fdq_sel[1]);
197 
198 		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
199 		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
200 		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
201 	}
202 
203 	/* Keep a copy of the cfg */
204 	memcpy(&chan->cfg, cfg, sizeof(*cfg));
205 	spin_unlock(&chan->lock);
206 
207 	return 0;
208 }
209 
210 static int chan_teardown(struct knav_dma_chan *chan)
211 {
212 	unsigned long end, value;
213 
214 	if (!chan->reg_chan)
215 		return 0;
216 
217 	/* indicate teardown */
218 	writel_relaxed(DMA_TEARDOWN, &chan->reg_chan->control);
219 
220 	/* wait for the dma to shut itself down */
221 	end = jiffies + msecs_to_jiffies(DMA_TIMEOUT);
222 	do {
223 		value = readl_relaxed(&chan->reg_chan->control);
224 		if ((value & DMA_ENABLE) == 0)
225 			break;
226 	} while (time_after(end, jiffies));
227 
228 	if (readl_relaxed(&chan->reg_chan->control) & DMA_ENABLE) {
229 		dev_err(kdev->dev, "timeout waiting for teardown\n");
230 		return -ETIMEDOUT;
231 	}
232 
233 	return 0;
234 }
235 
236 static void chan_stop(struct knav_dma_chan *chan)
237 {
238 	spin_lock(&chan->lock);
239 	if (chan->reg_rx_flow) {
240 		/* first detach fdqs, starve out the flow */
241 		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[0]);
242 		writel_relaxed(0, &chan->reg_rx_flow->fdq_sel[1]);
243 		writel_relaxed(0, &chan->reg_rx_flow->thresh[0]);
244 		writel_relaxed(0, &chan->reg_rx_flow->thresh[1]);
245 		writel_relaxed(0, &chan->reg_rx_flow->thresh[2]);
246 	}
247 
248 	/* teardown the dma channel */
249 	chan_teardown(chan);
250 
251 	/* then disconnect the completion side */
252 	if (chan->reg_rx_flow) {
253 		writel_relaxed(0, &chan->reg_rx_flow->control);
254 		writel_relaxed(0, &chan->reg_rx_flow->tags);
255 		writel_relaxed(0, &chan->reg_rx_flow->tag_sel);
256 	}
257 
258 	memset(&chan->cfg, 0, sizeof(struct knav_dma_cfg));
259 	spin_unlock(&chan->lock);
260 
261 	dev_dbg(kdev->dev, "channel stopped\n");
262 }
263 
264 static void dma_hw_enable_all(struct knav_dma_device *dma)
265 {
266 	int i;
267 
268 	for (i = 0; i < dma->max_tx_chan; i++) {
269 		writel_relaxed(0, &dma->reg_tx_chan[i].mode);
270 		writel_relaxed(DMA_ENABLE, &dma->reg_tx_chan[i].control);
271 	}
272 }
273 
274 
275 static void knav_dma_hw_init(struct knav_dma_device *dma)
276 {
277 	unsigned v;
278 	int i;
279 
280 	spin_lock(&dma->lock);
281 	v  = dma->loopback ? DMA_LOOPBACK : 0;
282 	writel_relaxed(v, &dma->reg_global->emulation_control);
283 
284 	v = readl_relaxed(&dma->reg_global->perf_control);
285 	v |= ((dma->rx_timeout & DMA_RX_TIMEOUT_MASK) << DMA_RX_TIMEOUT_SHIFT);
286 	writel_relaxed(v, &dma->reg_global->perf_control);
287 
288 	v = ((dma->tx_priority << DMA_TX_PRIO_SHIFT) |
289 	     (dma->rx_priority << DMA_RX_PRIO_SHIFT));
290 
291 	writel_relaxed(v, &dma->reg_global->priority_control);
292 
293 	/* Always enable all Rx channels. Rx paths are managed using flows */
294 	for (i = 0; i < dma->max_rx_chan; i++)
295 		writel_relaxed(DMA_ENABLE, &dma->reg_rx_chan[i].control);
296 
297 	for (i = 0; i < dma->logical_queue_managers; i++)
298 		writel_relaxed(dma->qm_base_address[i],
299 			       &dma->reg_global->qm_base_address[i]);
300 	spin_unlock(&dma->lock);
301 }
302 
303 static void knav_dma_hw_destroy(struct knav_dma_device *dma)
304 {
305 	int i;
306 	unsigned v;
307 
308 	spin_lock(&dma->lock);
309 	v = ~DMA_ENABLE & REG_MASK;
310 
311 	for (i = 0; i < dma->max_rx_chan; i++)
312 		writel_relaxed(v, &dma->reg_rx_chan[i].control);
313 
314 	for (i = 0; i < dma->max_tx_chan; i++)
315 		writel_relaxed(v, &dma->reg_tx_chan[i].control);
316 	spin_unlock(&dma->lock);
317 }
318 
319 static void dma_debug_show_channels(struct seq_file *s,
320 					struct knav_dma_chan *chan)
321 {
322 	int i;
323 
324 	seq_printf(s, "\t%s %d:\t",
325 		((chan->direction == DMA_MEM_TO_DEV) ? "tx chan" : "rx flow"),
326 		chan_number(chan));
327 
328 	if (chan->direction == DMA_MEM_TO_DEV) {
329 		seq_printf(s, "einfo - %d, pswords - %d, priority - %d\n",
330 			chan->cfg.u.tx.filt_einfo,
331 			chan->cfg.u.tx.filt_pswords,
332 			chan->cfg.u.tx.priority);
333 	} else {
334 		seq_printf(s, "einfo - %d, psinfo - %d, desc_type - %d\n",
335 			chan->cfg.u.rx.einfo_present,
336 			chan->cfg.u.rx.psinfo_present,
337 			chan->cfg.u.rx.desc_type);
338 		seq_printf(s, "\t\t\tdst_q: [%d], thresh: %d fdq: ",
339 			chan->cfg.u.rx.dst_q,
340 			chan->cfg.u.rx.thresh);
341 		for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN; i++)
342 			seq_printf(s, "[%d]", chan->cfg.u.rx.fdq[i]);
343 		seq_printf(s, "\n");
344 	}
345 }
346 
347 static void dma_debug_show_devices(struct seq_file *s,
348 					struct knav_dma_device *dma)
349 {
350 	struct knav_dma_chan *chan;
351 
352 	list_for_each_entry(chan, &dma->chan_list, list) {
353 		if (atomic_read(&chan->ref_count))
354 			dma_debug_show_channels(s, chan);
355 	}
356 }
357 
358 static int knav_dma_debug_show(struct seq_file *s, void *v)
359 {
360 	struct knav_dma_device *dma;
361 
362 	list_for_each_entry(dma, &kdev->list, list) {
363 		if (atomic_read(&dma->ref_count)) {
364 			seq_printf(s, "%s : max_tx_chan: (%d), max_rx_flows: (%d)\n",
365 			dma->name, dma->max_tx_chan, dma->max_rx_flow);
366 			dma_debug_show_devices(s, dma);
367 		}
368 	}
369 
370 	return 0;
371 }
372 
373 DEFINE_SHOW_ATTRIBUTE(knav_dma_debug);
374 
375 static int of_channel_match_helper(struct device_node *np, const char *name,
376 					const char **dma_instance)
377 {
378 	struct of_phandle_args args;
379 	struct device_node *dma_node;
380 	int index;
381 
382 	dma_node = of_parse_phandle(np, "ti,navigator-dmas", 0);
383 	if (!dma_node)
384 		return -ENODEV;
385 
386 	*dma_instance = dma_node->name;
387 	index = of_property_match_string(np, "ti,navigator-dma-names", name);
388 	if (index < 0) {
389 		dev_err(kdev->dev, "No 'ti,navigator-dma-names' property\n");
390 		return -ENODEV;
391 	}
392 
393 	if (of_parse_phandle_with_fixed_args(np, "ti,navigator-dmas",
394 					1, index, &args)) {
395 		dev_err(kdev->dev, "Missing the phandle args name %s\n", name);
396 		return -ENODEV;
397 	}
398 
399 	if (args.args[0] < 0) {
400 		dev_err(kdev->dev, "Missing args for %s\n", name);
401 		return -ENODEV;
402 	}
403 
404 	return args.args[0];
405 }
406 
407 /**
408  * knav_dma_open_channel() - try to setup an exclusive slave channel
409  * @dev:	pointer to client device structure
410  * @name:	slave channel name
411  * @config:	dma configuration parameters
412  *
413  * Returns pointer to appropriate DMA channel on success or error.
414  */
415 void *knav_dma_open_channel(struct device *dev, const char *name,
416 					struct knav_dma_cfg *config)
417 {
418 	struct knav_dma_device *dma = NULL, *iter1;
419 	struct knav_dma_chan *chan = NULL, *iter2;
420 	int chan_num = -1;
421 	const char *instance;
422 
423 	if (!kdev) {
424 		pr_err("keystone-navigator-dma driver not registered\n");
425 		return (void *)-EINVAL;
426 	}
427 
428 	chan_num = of_channel_match_helper(dev->of_node, name, &instance);
429 	if (chan_num < 0) {
430 		dev_err(kdev->dev, "No DMA instance with name %s\n", name);
431 		return (void *)-EINVAL;
432 	}
433 
434 	dev_dbg(kdev->dev, "initializing %s channel %d from DMA %s\n",
435 		  config->direction == DMA_MEM_TO_DEV ? "transmit" :
436 		  config->direction == DMA_DEV_TO_MEM ? "receive"  :
437 		  "unknown", chan_num, instance);
438 
439 	if (config->direction != DMA_MEM_TO_DEV &&
440 	    config->direction != DMA_DEV_TO_MEM) {
441 		dev_err(kdev->dev, "bad direction\n");
442 		return (void *)-EINVAL;
443 	}
444 
445 	/* Look for correct dma instance */
446 	list_for_each_entry(iter1, &kdev->list, list) {
447 		if (!strcmp(iter1->name, instance)) {
448 			dma = iter1;
449 			break;
450 		}
451 	}
452 	if (!dma) {
453 		dev_err(kdev->dev, "No DMA instance with name %s\n", instance);
454 		return (void *)-EINVAL;
455 	}
456 
457 	/* Look for correct dma channel from dma instance */
458 	list_for_each_entry(iter2, &dma->chan_list, list) {
459 		if (config->direction == DMA_MEM_TO_DEV) {
460 			if (iter2->channel == chan_num) {
461 				chan = iter2;
462 				break;
463 			}
464 		} else {
465 			if (iter2->flow == chan_num) {
466 				chan = iter2;
467 				break;
468 			}
469 		}
470 	}
471 	if (!chan) {
472 		dev_err(kdev->dev, "channel %d is not in DMA %s\n",
473 				chan_num, instance);
474 		return (void *)-EINVAL;
475 	}
476 
477 	if (atomic_read(&chan->ref_count) >= 1) {
478 		if (!check_config(chan, config)) {
479 			dev_err(kdev->dev, "channel %d config miss-match\n",
480 				chan_num);
481 			return (void *)-EINVAL;
482 		}
483 	}
484 
485 	if (atomic_inc_return(&chan->dma->ref_count) <= 1)
486 		knav_dma_hw_init(chan->dma);
487 
488 	if (atomic_inc_return(&chan->ref_count) <= 1)
489 		chan_start(chan, config);
490 
491 	dev_dbg(kdev->dev, "channel %d opened from DMA %s\n",
492 				chan_num, instance);
493 
494 	return chan;
495 }
496 EXPORT_SYMBOL_GPL(knav_dma_open_channel);
497 
498 /**
499  * knav_dma_close_channel()	- Destroy a dma channel
500  *
501  * @channel:	dma channel handle
502  *
503  */
504 void knav_dma_close_channel(void *channel)
505 {
506 	struct knav_dma_chan *chan = channel;
507 
508 	if (!kdev) {
509 		pr_err("keystone-navigator-dma driver not registered\n");
510 		return;
511 	}
512 
513 	if (atomic_dec_return(&chan->ref_count) <= 0)
514 		chan_stop(chan);
515 
516 	if (atomic_dec_return(&chan->dma->ref_count) <= 0)
517 		knav_dma_hw_destroy(chan->dma);
518 
519 	dev_dbg(kdev->dev, "channel %d or flow %d closed from DMA %s\n",
520 			chan->channel, chan->flow, chan->dma->name);
521 }
522 EXPORT_SYMBOL_GPL(knav_dma_close_channel);
523 
524 static void __iomem *pktdma_get_regs(struct knav_dma_device *dma,
525 				struct device_node *node,
526 				unsigned index, resource_size_t *_size)
527 {
528 	struct device *dev = kdev->dev;
529 	struct resource res;
530 	void __iomem *regs;
531 	int ret;
532 
533 	ret = of_address_to_resource(node, index, &res);
534 	if (ret) {
535 		dev_err(dev, "Can't translate of node(%pOFn) address for index(%d)\n",
536 			node, index);
537 		return ERR_PTR(ret);
538 	}
539 
540 	regs = devm_ioremap_resource(kdev->dev, &res);
541 	if (IS_ERR(regs))
542 		dev_err(dev, "Failed to map register base for index(%d) node(%pOFn)\n",
543 			index, node);
544 	if (_size)
545 		*_size = resource_size(&res);
546 
547 	return regs;
548 }
549 
550 static int pktdma_init_rx_chan(struct knav_dma_chan *chan, u32 flow)
551 {
552 	struct knav_dma_device *dma = chan->dma;
553 
554 	chan->flow = flow;
555 	chan->reg_rx_flow = dma->reg_rx_flow + flow;
556 	chan->channel = DMA_INVALID_ID;
557 	dev_dbg(kdev->dev, "rx flow(%d) (%p)\n", chan->flow, chan->reg_rx_flow);
558 
559 	return 0;
560 }
561 
562 static int pktdma_init_tx_chan(struct knav_dma_chan *chan, u32 channel)
563 {
564 	struct knav_dma_device *dma = chan->dma;
565 
566 	chan->channel = channel;
567 	chan->reg_chan = dma->reg_tx_chan + channel;
568 	chan->reg_tx_sched = dma->reg_tx_sched + channel;
569 	chan->flow = DMA_INVALID_ID;
570 	dev_dbg(kdev->dev, "tx channel(%d) (%p)\n", chan->channel, chan->reg_chan);
571 
572 	return 0;
573 }
574 
575 static int pktdma_init_chan(struct knav_dma_device *dma,
576 				enum dma_transfer_direction dir,
577 				unsigned chan_num)
578 {
579 	struct device *dev = kdev->dev;
580 	struct knav_dma_chan *chan;
581 	int ret = -EINVAL;
582 
583 	chan = devm_kzalloc(dev, sizeof(*chan), GFP_KERNEL);
584 	if (!chan)
585 		return -ENOMEM;
586 
587 	INIT_LIST_HEAD(&chan->list);
588 	chan->dma	= dma;
589 	chan->direction	= DMA_TRANS_NONE;
590 	atomic_set(&chan->ref_count, 0);
591 	spin_lock_init(&chan->lock);
592 
593 	if (dir == DMA_MEM_TO_DEV) {
594 		chan->direction = dir;
595 		ret = pktdma_init_tx_chan(chan, chan_num);
596 	} else if (dir == DMA_DEV_TO_MEM) {
597 		chan->direction = dir;
598 		ret = pktdma_init_rx_chan(chan, chan_num);
599 	} else {
600 		dev_err(dev, "channel(%d) direction unknown\n", chan_num);
601 	}
602 
603 	list_add_tail(&chan->list, &dma->chan_list);
604 
605 	return ret;
606 }
607 
608 static int dma_init(struct device_node *cloud, struct device_node *dma_node)
609 {
610 	unsigned max_tx_chan, max_rx_chan, max_rx_flow, max_tx_sched;
611 	struct device_node *node = dma_node;
612 	struct knav_dma_device *dma;
613 	int ret, len, num_chan = 0;
614 	resource_size_t size;
615 	u32 timeout;
616 	u32 i;
617 
618 	dma = devm_kzalloc(kdev->dev, sizeof(*dma), GFP_KERNEL);
619 	if (!dma) {
620 		dev_err(kdev->dev, "could not allocate driver mem\n");
621 		return -ENOMEM;
622 	}
623 	INIT_LIST_HEAD(&dma->list);
624 	INIT_LIST_HEAD(&dma->chan_list);
625 
626 	if (!of_find_property(cloud, "ti,navigator-cloud-address", &len)) {
627 		dev_err(kdev->dev, "unspecified navigator cloud addresses\n");
628 		return -ENODEV;
629 	}
630 
631 	dma->logical_queue_managers = len / sizeof(u32);
632 	if (dma->logical_queue_managers > DMA_MAX_QMS) {
633 		dev_warn(kdev->dev, "too many queue mgrs(>%d) rest ignored\n",
634 			 dma->logical_queue_managers);
635 		dma->logical_queue_managers = DMA_MAX_QMS;
636 	}
637 
638 	ret = of_property_read_u32_array(cloud, "ti,navigator-cloud-address",
639 					dma->qm_base_address,
640 					dma->logical_queue_managers);
641 	if (ret) {
642 		dev_err(kdev->dev, "invalid navigator cloud addresses\n");
643 		return -ENODEV;
644 	}
645 
646 	dma->reg_global	 = pktdma_get_regs(dma, node, 0, &size);
647 	if (IS_ERR(dma->reg_global))
648 		return PTR_ERR(dma->reg_global);
649 	if (size < sizeof(struct reg_global)) {
650 		dev_err(kdev->dev, "bad size %pa for global regs\n", &size);
651 		return -ENODEV;
652 	}
653 
654 	dma->reg_tx_chan = pktdma_get_regs(dma, node, 1, &size);
655 	if (IS_ERR(dma->reg_tx_chan))
656 		return PTR_ERR(dma->reg_tx_chan);
657 
658 	max_tx_chan = size / sizeof(struct reg_chan);
659 	dma->reg_rx_chan = pktdma_get_regs(dma, node, 2, &size);
660 	if (IS_ERR(dma->reg_rx_chan))
661 		return PTR_ERR(dma->reg_rx_chan);
662 
663 	max_rx_chan = size / sizeof(struct reg_chan);
664 	dma->reg_tx_sched = pktdma_get_regs(dma, node, 3, &size);
665 	if (IS_ERR(dma->reg_tx_sched))
666 		return PTR_ERR(dma->reg_tx_sched);
667 
668 	max_tx_sched = size / sizeof(struct reg_tx_sched);
669 	dma->reg_rx_flow = pktdma_get_regs(dma, node, 4, &size);
670 	if (IS_ERR(dma->reg_rx_flow))
671 		return PTR_ERR(dma->reg_rx_flow);
672 
673 	max_rx_flow = size / sizeof(struct reg_rx_flow);
674 	dma->rx_priority = DMA_PRIO_DEFAULT;
675 	dma->tx_priority = DMA_PRIO_DEFAULT;
676 
677 	dma->enable_all	= (of_get_property(node, "ti,enable-all", NULL) != NULL);
678 	dma->loopback	= (of_get_property(node, "ti,loop-back",  NULL) != NULL);
679 
680 	ret = of_property_read_u32(node, "ti,rx-retry-timeout", &timeout);
681 	if (ret < 0) {
682 		dev_dbg(kdev->dev, "unspecified rx timeout using value %d\n",
683 			DMA_RX_TIMEOUT_DEFAULT);
684 		timeout = DMA_RX_TIMEOUT_DEFAULT;
685 	}
686 
687 	dma->rx_timeout = timeout;
688 	dma->max_rx_chan = max_rx_chan;
689 	dma->max_rx_flow = max_rx_flow;
690 	dma->max_tx_chan = min(max_tx_chan, max_tx_sched);
691 	atomic_set(&dma->ref_count, 0);
692 	strcpy(dma->name, node->name);
693 	spin_lock_init(&dma->lock);
694 
695 	for (i = 0; i < dma->max_tx_chan; i++) {
696 		if (pktdma_init_chan(dma, DMA_MEM_TO_DEV, i) >= 0)
697 			num_chan++;
698 	}
699 
700 	for (i = 0; i < dma->max_rx_flow; i++) {
701 		if (pktdma_init_chan(dma, DMA_DEV_TO_MEM, i) >= 0)
702 			num_chan++;
703 	}
704 
705 	list_add_tail(&dma->list, &kdev->list);
706 
707 	/*
708 	 * For DSP software usecases or userpace transport software, setup all
709 	 * the DMA hardware resources.
710 	 */
711 	if (dma->enable_all) {
712 		atomic_inc(&dma->ref_count);
713 		knav_dma_hw_init(dma);
714 		dma_hw_enable_all(dma);
715 	}
716 
717 	dev_info(kdev->dev, "DMA %s registered %d logical channels, flows %d, tx chans: %d, rx chans: %d%s\n",
718 		dma->name, num_chan, dma->max_rx_flow,
719 		dma->max_tx_chan, dma->max_rx_chan,
720 		dma->loopback ? ", loopback" : "");
721 
722 	return 0;
723 }
724 
725 static int knav_dma_probe(struct platform_device *pdev)
726 {
727 	struct device *dev = &pdev->dev;
728 	struct device_node *node = pdev->dev.of_node;
729 	struct device_node *child;
730 	int ret = 0;
731 
732 	if (!node) {
733 		dev_err(&pdev->dev, "could not find device info\n");
734 		return -EINVAL;
735 	}
736 
737 	kdev = devm_kzalloc(dev,
738 			sizeof(struct knav_dma_pool_device), GFP_KERNEL);
739 	if (!kdev) {
740 		dev_err(dev, "could not allocate driver mem\n");
741 		return -ENOMEM;
742 	}
743 
744 	kdev->dev = dev;
745 	INIT_LIST_HEAD(&kdev->list);
746 
747 	pm_runtime_enable(kdev->dev);
748 	ret = pm_runtime_resume_and_get(kdev->dev);
749 	if (ret < 0) {
750 		dev_err(kdev->dev, "unable to enable pktdma, err %d\n", ret);
751 		goto err_pm_disable;
752 	}
753 
754 	/* Initialise all packet dmas */
755 	for_each_child_of_node(node, child) {
756 		ret = dma_init(node, child);
757 		if (ret) {
758 			of_node_put(child);
759 			dev_err(&pdev->dev, "init failed with %d\n", ret);
760 			break;
761 		}
762 	}
763 
764 	if (list_empty(&kdev->list)) {
765 		dev_err(dev, "no valid dma instance\n");
766 		ret = -ENODEV;
767 		goto err_put_sync;
768 	}
769 
770 	debugfs_create_file("knav_dma", S_IFREG | S_IRUGO, NULL, NULL,
771 			    &knav_dma_debug_fops);
772 
773 	device_ready = true;
774 	return ret;
775 
776 err_put_sync:
777 	pm_runtime_put_sync(kdev->dev);
778 err_pm_disable:
779 	pm_runtime_disable(kdev->dev);
780 
781 	return ret;
782 }
783 
784 static int knav_dma_remove(struct platform_device *pdev)
785 {
786 	struct knav_dma_device *dma;
787 
788 	list_for_each_entry(dma, &kdev->list, list) {
789 		if (atomic_dec_return(&dma->ref_count) == 0)
790 			knav_dma_hw_destroy(dma);
791 	}
792 
793 	pm_runtime_put_sync(&pdev->dev);
794 	pm_runtime_disable(&pdev->dev);
795 
796 	return 0;
797 }
798 
799 static struct of_device_id of_match[] = {
800 	{ .compatible = "ti,keystone-navigator-dma", },
801 	{},
802 };
803 
804 MODULE_DEVICE_TABLE(of, of_match);
805 
806 static struct platform_driver knav_dma_driver = {
807 	.probe	= knav_dma_probe,
808 	.remove	= knav_dma_remove,
809 	.driver = {
810 		.name		= "keystone-navigator-dma",
811 		.of_match_table	= of_match,
812 	},
813 };
814 module_platform_driver(knav_dma_driver);
815 
816 MODULE_LICENSE("GPL v2");
817 MODULE_DESCRIPTION("TI Keystone Navigator Packet DMA driver");
818 MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com>");
819 MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");
820