xref: /linux/drivers/soc/ti/knav_dma.c (revision be58f7103700a68d5c7ca60a2bc0b309907599ab)
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_chan *chan;
419 	struct knav_dma_device *dma;
420 	bool found = false;
421 	int chan_num = -1;
422 	const char *instance;
423 
424 	if (!kdev) {
425 		pr_err("keystone-navigator-dma driver not registered\n");
426 		return (void *)-EINVAL;
427 	}
428 
429 	chan_num = of_channel_match_helper(dev->of_node, name, &instance);
430 	if (chan_num < 0) {
431 		dev_err(kdev->dev, "No DMA instance with name %s\n", name);
432 		return (void *)-EINVAL;
433 	}
434 
435 	dev_dbg(kdev->dev, "initializing %s channel %d from DMA %s\n",
436 		  config->direction == DMA_MEM_TO_DEV ? "transmit" :
437 		  config->direction == DMA_DEV_TO_MEM ? "receive"  :
438 		  "unknown", chan_num, instance);
439 
440 	if (config->direction != DMA_MEM_TO_DEV &&
441 	    config->direction != DMA_DEV_TO_MEM) {
442 		dev_err(kdev->dev, "bad direction\n");
443 		return (void *)-EINVAL;
444 	}
445 
446 	/* Look for correct dma instance */
447 	list_for_each_entry(dma, &kdev->list, list) {
448 		if (!strcmp(dma->name, instance)) {
449 			found = true;
450 			break;
451 		}
452 	}
453 	if (!found) {
454 		dev_err(kdev->dev, "No DMA instance with name %s\n", instance);
455 		return (void *)-EINVAL;
456 	}
457 
458 	/* Look for correct dma channel from dma instance */
459 	found = false;
460 	list_for_each_entry(chan, &dma->chan_list, list) {
461 		if (config->direction == DMA_MEM_TO_DEV) {
462 			if (chan->channel == chan_num) {
463 				found = true;
464 				break;
465 			}
466 		} else {
467 			if (chan->flow == chan_num) {
468 				found = true;
469 				break;
470 			}
471 		}
472 	}
473 	if (!found) {
474 		dev_err(kdev->dev, "channel %d is not in DMA %s\n",
475 				chan_num, instance);
476 		return (void *)-EINVAL;
477 	}
478 
479 	if (atomic_read(&chan->ref_count) >= 1) {
480 		if (!check_config(chan, config)) {
481 			dev_err(kdev->dev, "channel %d config miss-match\n",
482 				chan_num);
483 			return (void *)-EINVAL;
484 		}
485 	}
486 
487 	if (atomic_inc_return(&chan->dma->ref_count) <= 1)
488 		knav_dma_hw_init(chan->dma);
489 
490 	if (atomic_inc_return(&chan->ref_count) <= 1)
491 		chan_start(chan, config);
492 
493 	dev_dbg(kdev->dev, "channel %d opened from DMA %s\n",
494 				chan_num, instance);
495 
496 	return chan;
497 }
498 EXPORT_SYMBOL_GPL(knav_dma_open_channel);
499 
500 /**
501  * knav_dma_close_channel()	- Destroy a dma channel
502  *
503  * @channel:	dma channel handle
504  *
505  */
506 void knav_dma_close_channel(void *channel)
507 {
508 	struct knav_dma_chan *chan = channel;
509 
510 	if (!kdev) {
511 		pr_err("keystone-navigator-dma driver not registered\n");
512 		return;
513 	}
514 
515 	if (atomic_dec_return(&chan->ref_count) <= 0)
516 		chan_stop(chan);
517 
518 	if (atomic_dec_return(&chan->dma->ref_count) <= 0)
519 		knav_dma_hw_destroy(chan->dma);
520 
521 	dev_dbg(kdev->dev, "channel %d or flow %d closed from DMA %s\n",
522 			chan->channel, chan->flow, chan->dma->name);
523 }
524 EXPORT_SYMBOL_GPL(knav_dma_close_channel);
525 
526 static void __iomem *pktdma_get_regs(struct knav_dma_device *dma,
527 				struct device_node *node,
528 				unsigned index, resource_size_t *_size)
529 {
530 	struct device *dev = kdev->dev;
531 	struct resource res;
532 	void __iomem *regs;
533 	int ret;
534 
535 	ret = of_address_to_resource(node, index, &res);
536 	if (ret) {
537 		dev_err(dev, "Can't translate of node(%pOFn) address for index(%d)\n",
538 			node, index);
539 		return ERR_PTR(ret);
540 	}
541 
542 	regs = devm_ioremap_resource(kdev->dev, &res);
543 	if (IS_ERR(regs))
544 		dev_err(dev, "Failed to map register base for index(%d) node(%pOFn)\n",
545 			index, node);
546 	if (_size)
547 		*_size = resource_size(&res);
548 
549 	return regs;
550 }
551 
552 static int pktdma_init_rx_chan(struct knav_dma_chan *chan, u32 flow)
553 {
554 	struct knav_dma_device *dma = chan->dma;
555 
556 	chan->flow = flow;
557 	chan->reg_rx_flow = dma->reg_rx_flow + flow;
558 	chan->channel = DMA_INVALID_ID;
559 	dev_dbg(kdev->dev, "rx flow(%d) (%p)\n", chan->flow, chan->reg_rx_flow);
560 
561 	return 0;
562 }
563 
564 static int pktdma_init_tx_chan(struct knav_dma_chan *chan, u32 channel)
565 {
566 	struct knav_dma_device *dma = chan->dma;
567 
568 	chan->channel = channel;
569 	chan->reg_chan = dma->reg_tx_chan + channel;
570 	chan->reg_tx_sched = dma->reg_tx_sched + channel;
571 	chan->flow = DMA_INVALID_ID;
572 	dev_dbg(kdev->dev, "tx channel(%d) (%p)\n", chan->channel, chan->reg_chan);
573 
574 	return 0;
575 }
576 
577 static int pktdma_init_chan(struct knav_dma_device *dma,
578 				enum dma_transfer_direction dir,
579 				unsigned chan_num)
580 {
581 	struct device *dev = kdev->dev;
582 	struct knav_dma_chan *chan;
583 	int ret = -EINVAL;
584 
585 	chan = devm_kzalloc(dev, sizeof(*chan), GFP_KERNEL);
586 	if (!chan)
587 		return -ENOMEM;
588 
589 	INIT_LIST_HEAD(&chan->list);
590 	chan->dma	= dma;
591 	chan->direction	= DMA_TRANS_NONE;
592 	atomic_set(&chan->ref_count, 0);
593 	spin_lock_init(&chan->lock);
594 
595 	if (dir == DMA_MEM_TO_DEV) {
596 		chan->direction = dir;
597 		ret = pktdma_init_tx_chan(chan, chan_num);
598 	} else if (dir == DMA_DEV_TO_MEM) {
599 		chan->direction = dir;
600 		ret = pktdma_init_rx_chan(chan, chan_num);
601 	} else {
602 		dev_err(dev, "channel(%d) direction unknown\n", chan_num);
603 	}
604 
605 	list_add_tail(&chan->list, &dma->chan_list);
606 
607 	return ret;
608 }
609 
610 static int dma_init(struct device_node *cloud, struct device_node *dma_node)
611 {
612 	unsigned max_tx_chan, max_rx_chan, max_rx_flow, max_tx_sched;
613 	struct device_node *node = dma_node;
614 	struct knav_dma_device *dma;
615 	int ret, len, num_chan = 0;
616 	resource_size_t size;
617 	u32 timeout;
618 	u32 i;
619 
620 	dma = devm_kzalloc(kdev->dev, sizeof(*dma), GFP_KERNEL);
621 	if (!dma) {
622 		dev_err(kdev->dev, "could not allocate driver mem\n");
623 		return -ENOMEM;
624 	}
625 	INIT_LIST_HEAD(&dma->list);
626 	INIT_LIST_HEAD(&dma->chan_list);
627 
628 	if (!of_find_property(cloud, "ti,navigator-cloud-address", &len)) {
629 		dev_err(kdev->dev, "unspecified navigator cloud addresses\n");
630 		return -ENODEV;
631 	}
632 
633 	dma->logical_queue_managers = len / sizeof(u32);
634 	if (dma->logical_queue_managers > DMA_MAX_QMS) {
635 		dev_warn(kdev->dev, "too many queue mgrs(>%d) rest ignored\n",
636 			 dma->logical_queue_managers);
637 		dma->logical_queue_managers = DMA_MAX_QMS;
638 	}
639 
640 	ret = of_property_read_u32_array(cloud, "ti,navigator-cloud-address",
641 					dma->qm_base_address,
642 					dma->logical_queue_managers);
643 	if (ret) {
644 		dev_err(kdev->dev, "invalid navigator cloud addresses\n");
645 		return -ENODEV;
646 	}
647 
648 	dma->reg_global	 = pktdma_get_regs(dma, node, 0, &size);
649 	if (!dma->reg_global)
650 		return -ENODEV;
651 	if (size < sizeof(struct reg_global)) {
652 		dev_err(kdev->dev, "bad size %pa for global regs\n", &size);
653 		return -ENODEV;
654 	}
655 
656 	dma->reg_tx_chan = pktdma_get_regs(dma, node, 1, &size);
657 	if (!dma->reg_tx_chan)
658 		return -ENODEV;
659 
660 	max_tx_chan = size / sizeof(struct reg_chan);
661 	dma->reg_rx_chan = pktdma_get_regs(dma, node, 2, &size);
662 	if (!dma->reg_rx_chan)
663 		return -ENODEV;
664 
665 	max_rx_chan = size / sizeof(struct reg_chan);
666 	dma->reg_tx_sched = pktdma_get_regs(dma, node, 3, &size);
667 	if (!dma->reg_tx_sched)
668 		return -ENODEV;
669 
670 	max_tx_sched = size / sizeof(struct reg_tx_sched);
671 	dma->reg_rx_flow = pktdma_get_regs(dma, node, 4, &size);
672 	if (!dma->reg_rx_flow)
673 		return -ENODEV;
674 
675 	max_rx_flow = size / sizeof(struct reg_rx_flow);
676 	dma->rx_priority = DMA_PRIO_DEFAULT;
677 	dma->tx_priority = DMA_PRIO_DEFAULT;
678 
679 	dma->enable_all	= (of_get_property(node, "ti,enable-all", NULL) != NULL);
680 	dma->loopback	= (of_get_property(node, "ti,loop-back",  NULL) != NULL);
681 
682 	ret = of_property_read_u32(node, "ti,rx-retry-timeout", &timeout);
683 	if (ret < 0) {
684 		dev_dbg(kdev->dev, "unspecified rx timeout using value %d\n",
685 			DMA_RX_TIMEOUT_DEFAULT);
686 		timeout = DMA_RX_TIMEOUT_DEFAULT;
687 	}
688 
689 	dma->rx_timeout = timeout;
690 	dma->max_rx_chan = max_rx_chan;
691 	dma->max_rx_flow = max_rx_flow;
692 	dma->max_tx_chan = min(max_tx_chan, max_tx_sched);
693 	atomic_set(&dma->ref_count, 0);
694 	strcpy(dma->name, node->name);
695 	spin_lock_init(&dma->lock);
696 
697 	for (i = 0; i < dma->max_tx_chan; i++) {
698 		if (pktdma_init_chan(dma, DMA_MEM_TO_DEV, i) >= 0)
699 			num_chan++;
700 	}
701 
702 	for (i = 0; i < dma->max_rx_flow; i++) {
703 		if (pktdma_init_chan(dma, DMA_DEV_TO_MEM, i) >= 0)
704 			num_chan++;
705 	}
706 
707 	list_add_tail(&dma->list, &kdev->list);
708 
709 	/*
710 	 * For DSP software usecases or userpace transport software, setup all
711 	 * the DMA hardware resources.
712 	 */
713 	if (dma->enable_all) {
714 		atomic_inc(&dma->ref_count);
715 		knav_dma_hw_init(dma);
716 		dma_hw_enable_all(dma);
717 	}
718 
719 	dev_info(kdev->dev, "DMA %s registered %d logical channels, flows %d, tx chans: %d, rx chans: %d%s\n",
720 		dma->name, num_chan, dma->max_rx_flow,
721 		dma->max_tx_chan, dma->max_rx_chan,
722 		dma->loopback ? ", loopback" : "");
723 
724 	return 0;
725 }
726 
727 static int knav_dma_probe(struct platform_device *pdev)
728 {
729 	struct device *dev = &pdev->dev;
730 	struct device_node *node = pdev->dev.of_node;
731 	struct device_node *child;
732 	int ret = 0;
733 
734 	if (!node) {
735 		dev_err(&pdev->dev, "could not find device info\n");
736 		return -EINVAL;
737 	}
738 
739 	kdev = devm_kzalloc(dev,
740 			sizeof(struct knav_dma_pool_device), GFP_KERNEL);
741 	if (!kdev) {
742 		dev_err(dev, "could not allocate driver mem\n");
743 		return -ENOMEM;
744 	}
745 
746 	kdev->dev = dev;
747 	INIT_LIST_HEAD(&kdev->list);
748 
749 	pm_runtime_enable(kdev->dev);
750 	ret = pm_runtime_get_sync(kdev->dev);
751 	if (ret < 0) {
752 		pm_runtime_put_noidle(kdev->dev);
753 		dev_err(kdev->dev, "unable to enable pktdma, err %d\n", ret);
754 		goto err_pm_disable;
755 	}
756 
757 	/* Initialise all packet dmas */
758 	for_each_child_of_node(node, child) {
759 		ret = dma_init(node, child);
760 		if (ret) {
761 			of_node_put(child);
762 			dev_err(&pdev->dev, "init failed with %d\n", ret);
763 			break;
764 		}
765 	}
766 
767 	if (list_empty(&kdev->list)) {
768 		dev_err(dev, "no valid dma instance\n");
769 		ret = -ENODEV;
770 		goto err_put_sync;
771 	}
772 
773 	debugfs_create_file("knav_dma", S_IFREG | S_IRUGO, NULL, NULL,
774 			    &knav_dma_debug_fops);
775 
776 	device_ready = true;
777 	return ret;
778 
779 err_put_sync:
780 	pm_runtime_put_sync(kdev->dev);
781 err_pm_disable:
782 	pm_runtime_disable(kdev->dev);
783 
784 	return ret;
785 }
786 
787 static int knav_dma_remove(struct platform_device *pdev)
788 {
789 	struct knav_dma_device *dma;
790 
791 	list_for_each_entry(dma, &kdev->list, list) {
792 		if (atomic_dec_return(&dma->ref_count) == 0)
793 			knav_dma_hw_destroy(dma);
794 	}
795 
796 	pm_runtime_put_sync(&pdev->dev);
797 	pm_runtime_disable(&pdev->dev);
798 
799 	return 0;
800 }
801 
802 static struct of_device_id of_match[] = {
803 	{ .compatible = "ti,keystone-navigator-dma", },
804 	{},
805 };
806 
807 MODULE_DEVICE_TABLE(of, of_match);
808 
809 static struct platform_driver knav_dma_driver = {
810 	.probe	= knav_dma_probe,
811 	.remove	= knav_dma_remove,
812 	.driver = {
813 		.name		= "keystone-navigator-dma",
814 		.of_match_table	= of_match,
815 	},
816 };
817 module_platform_driver(knav_dma_driver);
818 
819 MODULE_LICENSE("GPL v2");
820 MODULE_DESCRIPTION("TI Keystone Navigator Packet DMA driver");
821 MODULE_AUTHOR("Sandeep Nair <sandeep_n@ti.com>");
822 MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");
823