xref: /openbmc/linux/drivers/dma/ti/cppi41.c (revision 2c6467d2)
1 #include <linux/delay.h>
2 #include <linux/dmaengine.h>
3 #include <linux/dma-mapping.h>
4 #include <linux/platform_device.h>
5 #include <linux/module.h>
6 #include <linux/of.h>
7 #include <linux/slab.h>
8 #include <linux/of_dma.h>
9 #include <linux/of_irq.h>
10 #include <linux/dmapool.h>
11 #include <linux/interrupt.h>
12 #include <linux/of_address.h>
13 #include <linux/pm_runtime.h>
14 #include "../dmaengine.h"
15 
16 #define DESC_TYPE	27
17 #define DESC_TYPE_HOST	0x10
18 #define DESC_TYPE_TEARD	0x13
19 
20 #define TD_DESC_IS_RX	(1 << 16)
21 #define TD_DESC_DMA_NUM	10
22 
23 #define DESC_LENGTH_BITS_NUM	21
24 
25 #define DESC_TYPE_USB	(5 << 26)
26 #define DESC_PD_COMPLETE	(1 << 31)
27 
28 /* DMA engine */
29 #define DMA_TDFDQ	4
30 #define DMA_TXGCR(x)	(0x800 + (x) * 0x20)
31 #define DMA_RXGCR(x)	(0x808 + (x) * 0x20)
32 #define RXHPCRA0		4
33 
34 #define GCR_CHAN_ENABLE		(1 << 31)
35 #define GCR_TEARDOWN		(1 << 30)
36 #define GCR_STARV_RETRY		(1 << 24)
37 #define GCR_DESC_TYPE_HOST	(1 << 14)
38 
39 /* DMA scheduler */
40 #define DMA_SCHED_CTRL		0
41 #define DMA_SCHED_CTRL_EN	(1 << 31)
42 #define DMA_SCHED_WORD(x)	((x) * 4 + 0x800)
43 
44 #define SCHED_ENTRY0_CHAN(x)	((x) << 0)
45 #define SCHED_ENTRY0_IS_RX	(1 << 7)
46 
47 #define SCHED_ENTRY1_CHAN(x)	((x) << 8)
48 #define SCHED_ENTRY1_IS_RX	(1 << 15)
49 
50 #define SCHED_ENTRY2_CHAN(x)	((x) << 16)
51 #define SCHED_ENTRY2_IS_RX	(1 << 23)
52 
53 #define SCHED_ENTRY3_CHAN(x)	((x) << 24)
54 #define SCHED_ENTRY3_IS_RX	(1 << 31)
55 
56 /* Queue manager */
57 /* 4 KiB of memory for descriptors, 2 for each endpoint */
58 #define ALLOC_DECS_NUM		128
59 #define DESCS_AREAS		1
60 #define TOTAL_DESCS_NUM		(ALLOC_DECS_NUM * DESCS_AREAS)
61 #define QMGR_SCRATCH_SIZE	(TOTAL_DESCS_NUM * 4)
62 
63 #define QMGR_LRAM0_BASE		0x80
64 #define QMGR_LRAM_SIZE		0x84
65 #define QMGR_LRAM1_BASE		0x88
66 #define QMGR_MEMBASE(x)		(0x1000 + (x) * 0x10)
67 #define QMGR_MEMCTRL(x)		(0x1004 + (x) * 0x10)
68 #define QMGR_MEMCTRL_IDX_SH	16
69 #define QMGR_MEMCTRL_DESC_SH	8
70 
71 #define QMGR_PEND(x)	(0x90 + (x) * 4)
72 
73 #define QMGR_PENDING_SLOT_Q(x)	(x / 32)
74 #define QMGR_PENDING_BIT_Q(x)	(x % 32)
75 
76 #define QMGR_QUEUE_A(n)	(0x2000 + (n) * 0x10)
77 #define QMGR_QUEUE_B(n)	(0x2004 + (n) * 0x10)
78 #define QMGR_QUEUE_C(n)	(0x2008 + (n) * 0x10)
79 #define QMGR_QUEUE_D(n)	(0x200c + (n) * 0x10)
80 
81 /* Packet Descriptor */
82 #define PD2_ZERO_LENGTH		(1 << 19)
83 
84 struct cppi41_channel {
85 	struct dma_chan chan;
86 	struct dma_async_tx_descriptor txd;
87 	struct cppi41_dd *cdd;
88 	struct cppi41_desc *desc;
89 	dma_addr_t desc_phys;
90 	void __iomem *gcr_reg;
91 	int is_tx;
92 	u32 residue;
93 
94 	unsigned int q_num;
95 	unsigned int q_comp_num;
96 	unsigned int port_num;
97 
98 	unsigned td_retry;
99 	unsigned td_queued:1;
100 	unsigned td_seen:1;
101 	unsigned td_desc_seen:1;
102 
103 	struct list_head node;		/* Node for pending list */
104 };
105 
106 struct cppi41_desc {
107 	u32 pd0;
108 	u32 pd1;
109 	u32 pd2;
110 	u32 pd3;
111 	u32 pd4;
112 	u32 pd5;
113 	u32 pd6;
114 	u32 pd7;
115 } __aligned(32);
116 
117 struct chan_queues {
118 	u16 submit;
119 	u16 complete;
120 };
121 
122 struct cppi41_dd {
123 	struct dma_device ddev;
124 
125 	void *qmgr_scratch;
126 	dma_addr_t scratch_phys;
127 
128 	struct cppi41_desc *cd;
129 	dma_addr_t descs_phys;
130 	u32 first_td_desc;
131 	struct cppi41_channel *chan_busy[ALLOC_DECS_NUM];
132 
133 	void __iomem *ctrl_mem;
134 	void __iomem *sched_mem;
135 	void __iomem *qmgr_mem;
136 	unsigned int irq;
137 	const struct chan_queues *queues_rx;
138 	const struct chan_queues *queues_tx;
139 	struct chan_queues td_queue;
140 	u16 first_completion_queue;
141 	u16 qmgr_num_pend;
142 	u32 n_chans;
143 	u8 platform;
144 
145 	struct list_head pending;	/* Pending queued transfers */
146 	spinlock_t lock;		/* Lock for pending list */
147 
148 	/* context for suspend/resume */
149 	unsigned int dma_tdfdq;
150 
151 	bool is_suspended;
152 };
153 
154 static struct chan_queues am335x_usb_queues_tx[] = {
155 	/* USB0 ENDP 1 */
156 	[ 0] = { .submit = 32, .complete =  93},
157 	[ 1] = { .submit = 34, .complete =  94},
158 	[ 2] = { .submit = 36, .complete =  95},
159 	[ 3] = { .submit = 38, .complete =  96},
160 	[ 4] = { .submit = 40, .complete =  97},
161 	[ 5] = { .submit = 42, .complete =  98},
162 	[ 6] = { .submit = 44, .complete =  99},
163 	[ 7] = { .submit = 46, .complete = 100},
164 	[ 8] = { .submit = 48, .complete = 101},
165 	[ 9] = { .submit = 50, .complete = 102},
166 	[10] = { .submit = 52, .complete = 103},
167 	[11] = { .submit = 54, .complete = 104},
168 	[12] = { .submit = 56, .complete = 105},
169 	[13] = { .submit = 58, .complete = 106},
170 	[14] = { .submit = 60, .complete = 107},
171 
172 	/* USB1 ENDP1 */
173 	[15] = { .submit = 62, .complete = 125},
174 	[16] = { .submit = 64, .complete = 126},
175 	[17] = { .submit = 66, .complete = 127},
176 	[18] = { .submit = 68, .complete = 128},
177 	[19] = { .submit = 70, .complete = 129},
178 	[20] = { .submit = 72, .complete = 130},
179 	[21] = { .submit = 74, .complete = 131},
180 	[22] = { .submit = 76, .complete = 132},
181 	[23] = { .submit = 78, .complete = 133},
182 	[24] = { .submit = 80, .complete = 134},
183 	[25] = { .submit = 82, .complete = 135},
184 	[26] = { .submit = 84, .complete = 136},
185 	[27] = { .submit = 86, .complete = 137},
186 	[28] = { .submit = 88, .complete = 138},
187 	[29] = { .submit = 90, .complete = 139},
188 };
189 
190 static const struct chan_queues am335x_usb_queues_rx[] = {
191 	/* USB0 ENDP 1 */
192 	[ 0] = { .submit =  1, .complete = 109},
193 	[ 1] = { .submit =  2, .complete = 110},
194 	[ 2] = { .submit =  3, .complete = 111},
195 	[ 3] = { .submit =  4, .complete = 112},
196 	[ 4] = { .submit =  5, .complete = 113},
197 	[ 5] = { .submit =  6, .complete = 114},
198 	[ 6] = { .submit =  7, .complete = 115},
199 	[ 7] = { .submit =  8, .complete = 116},
200 	[ 8] = { .submit =  9, .complete = 117},
201 	[ 9] = { .submit = 10, .complete = 118},
202 	[10] = { .submit = 11, .complete = 119},
203 	[11] = { .submit = 12, .complete = 120},
204 	[12] = { .submit = 13, .complete = 121},
205 	[13] = { .submit = 14, .complete = 122},
206 	[14] = { .submit = 15, .complete = 123},
207 
208 	/* USB1 ENDP 1 */
209 	[15] = { .submit = 16, .complete = 141},
210 	[16] = { .submit = 17, .complete = 142},
211 	[17] = { .submit = 18, .complete = 143},
212 	[18] = { .submit = 19, .complete = 144},
213 	[19] = { .submit = 20, .complete = 145},
214 	[20] = { .submit = 21, .complete = 146},
215 	[21] = { .submit = 22, .complete = 147},
216 	[22] = { .submit = 23, .complete = 148},
217 	[23] = { .submit = 24, .complete = 149},
218 	[24] = { .submit = 25, .complete = 150},
219 	[25] = { .submit = 26, .complete = 151},
220 	[26] = { .submit = 27, .complete = 152},
221 	[27] = { .submit = 28, .complete = 153},
222 	[28] = { .submit = 29, .complete = 154},
223 	[29] = { .submit = 30, .complete = 155},
224 };
225 
226 static const struct chan_queues da8xx_usb_queues_tx[] = {
227 	[0] = { .submit =  16, .complete = 24},
228 	[1] = { .submit =  18, .complete = 24},
229 	[2] = { .submit =  20, .complete = 24},
230 	[3] = { .submit =  22, .complete = 24},
231 };
232 
233 static const struct chan_queues da8xx_usb_queues_rx[] = {
234 	[0] = { .submit =  1, .complete = 26},
235 	[1] = { .submit =  3, .complete = 26},
236 	[2] = { .submit =  5, .complete = 26},
237 	[3] = { .submit =  7, .complete = 26},
238 };
239 
240 struct cppi_glue_infos {
241 	const struct chan_queues *queues_rx;
242 	const struct chan_queues *queues_tx;
243 	struct chan_queues td_queue;
244 	u16 first_completion_queue;
245 	u16 qmgr_num_pend;
246 };
247 
248 static struct cppi41_channel *to_cpp41_chan(struct dma_chan *c)
249 {
250 	return container_of(c, struct cppi41_channel, chan);
251 }
252 
253 static struct cppi41_channel *desc_to_chan(struct cppi41_dd *cdd, u32 desc)
254 {
255 	struct cppi41_channel *c;
256 	u32 descs_size;
257 	u32 desc_num;
258 
259 	descs_size = sizeof(struct cppi41_desc) * ALLOC_DECS_NUM;
260 
261 	if (!((desc >= cdd->descs_phys) &&
262 			(desc < (cdd->descs_phys + descs_size)))) {
263 		return NULL;
264 	}
265 
266 	desc_num = (desc - cdd->descs_phys) / sizeof(struct cppi41_desc);
267 	BUG_ON(desc_num >= ALLOC_DECS_NUM);
268 	c = cdd->chan_busy[desc_num];
269 	cdd->chan_busy[desc_num] = NULL;
270 
271 	/* Usecount for chan_busy[], paired with push_desc_queue() */
272 	pm_runtime_put(cdd->ddev.dev);
273 
274 	return c;
275 }
276 
277 static void cppi_writel(u32 val, void *__iomem *mem)
278 {
279 	__raw_writel(val, mem);
280 }
281 
282 static u32 cppi_readl(void *__iomem *mem)
283 {
284 	return __raw_readl(mem);
285 }
286 
287 static u32 pd_trans_len(u32 val)
288 {
289 	return val & ((1 << (DESC_LENGTH_BITS_NUM + 1)) - 1);
290 }
291 
292 static u32 cppi41_pop_desc(struct cppi41_dd *cdd, unsigned queue_num)
293 {
294 	u32 desc;
295 
296 	desc = cppi_readl(cdd->qmgr_mem + QMGR_QUEUE_D(queue_num));
297 	desc &= ~0x1f;
298 	return desc;
299 }
300 
301 static irqreturn_t cppi41_irq(int irq, void *data)
302 {
303 	struct cppi41_dd *cdd = data;
304 	u16 first_completion_queue = cdd->first_completion_queue;
305 	u16 qmgr_num_pend = cdd->qmgr_num_pend;
306 	struct cppi41_channel *c;
307 	int i;
308 
309 	for (i = QMGR_PENDING_SLOT_Q(first_completion_queue); i < qmgr_num_pend;
310 			i++) {
311 		u32 val;
312 		u32 q_num;
313 
314 		val = cppi_readl(cdd->qmgr_mem + QMGR_PEND(i));
315 		if (i == QMGR_PENDING_SLOT_Q(first_completion_queue) && val) {
316 			u32 mask;
317 			/* set corresponding bit for completetion Q 93 */
318 			mask = 1 << QMGR_PENDING_BIT_Q(first_completion_queue);
319 			/* not set all bits for queues less than Q 93 */
320 			mask--;
321 			/* now invert and keep only Q 93+ set */
322 			val &= ~mask;
323 		}
324 
325 		if (val)
326 			__iormb();
327 
328 		while (val) {
329 			u32 desc, len;
330 
331 			/*
332 			 * This should never trigger, see the comments in
333 			 * push_desc_queue()
334 			 */
335 			WARN_ON(cdd->is_suspended);
336 
337 			q_num = __fls(val);
338 			val &= ~(1 << q_num);
339 			q_num += 32 * i;
340 			desc = cppi41_pop_desc(cdd, q_num);
341 			c = desc_to_chan(cdd, desc);
342 			if (WARN_ON(!c)) {
343 				pr_err("%s() q %d desc %08x\n", __func__,
344 						q_num, desc);
345 				continue;
346 			}
347 
348 			if (c->desc->pd2 & PD2_ZERO_LENGTH)
349 				len = 0;
350 			else
351 				len = pd_trans_len(c->desc->pd0);
352 
353 			c->residue = pd_trans_len(c->desc->pd6) - len;
354 			dma_cookie_complete(&c->txd);
355 			dmaengine_desc_get_callback_invoke(&c->txd, NULL);
356 		}
357 	}
358 	return IRQ_HANDLED;
359 }
360 
361 static dma_cookie_t cppi41_tx_submit(struct dma_async_tx_descriptor *tx)
362 {
363 	dma_cookie_t cookie;
364 
365 	cookie = dma_cookie_assign(tx);
366 
367 	return cookie;
368 }
369 
370 static int cppi41_dma_alloc_chan_resources(struct dma_chan *chan)
371 {
372 	struct cppi41_channel *c = to_cpp41_chan(chan);
373 	struct cppi41_dd *cdd = c->cdd;
374 	int error;
375 
376 	error = pm_runtime_get_sync(cdd->ddev.dev);
377 	if (error < 0) {
378 		dev_err(cdd->ddev.dev, "%s pm runtime get: %i\n",
379 			__func__, error);
380 		pm_runtime_put_noidle(cdd->ddev.dev);
381 
382 		return error;
383 	}
384 
385 	dma_cookie_init(chan);
386 	dma_async_tx_descriptor_init(&c->txd, chan);
387 	c->txd.tx_submit = cppi41_tx_submit;
388 
389 	if (!c->is_tx)
390 		cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
391 
392 	pm_runtime_mark_last_busy(cdd->ddev.dev);
393 	pm_runtime_put_autosuspend(cdd->ddev.dev);
394 
395 	return 0;
396 }
397 
398 static void cppi41_dma_free_chan_resources(struct dma_chan *chan)
399 {
400 	struct cppi41_channel *c = to_cpp41_chan(chan);
401 	struct cppi41_dd *cdd = c->cdd;
402 	int error;
403 
404 	error = pm_runtime_get_sync(cdd->ddev.dev);
405 	if (error < 0) {
406 		pm_runtime_put_noidle(cdd->ddev.dev);
407 
408 		return;
409 	}
410 
411 	WARN_ON(!list_empty(&cdd->pending));
412 
413 	pm_runtime_mark_last_busy(cdd->ddev.dev);
414 	pm_runtime_put_autosuspend(cdd->ddev.dev);
415 }
416 
417 static enum dma_status cppi41_dma_tx_status(struct dma_chan *chan,
418 	dma_cookie_t cookie, struct dma_tx_state *txstate)
419 {
420 	struct cppi41_channel *c = to_cpp41_chan(chan);
421 	enum dma_status ret;
422 
423 	ret = dma_cookie_status(chan, cookie, txstate);
424 
425 	dma_set_residue(txstate, c->residue);
426 
427 	return ret;
428 }
429 
430 static void push_desc_queue(struct cppi41_channel *c)
431 {
432 	struct cppi41_dd *cdd = c->cdd;
433 	u32 desc_num;
434 	u32 desc_phys;
435 	u32 reg;
436 
437 	c->residue = 0;
438 
439 	reg = GCR_CHAN_ENABLE;
440 	if (!c->is_tx) {
441 		reg |= GCR_STARV_RETRY;
442 		reg |= GCR_DESC_TYPE_HOST;
443 		reg |= c->q_comp_num;
444 	}
445 
446 	cppi_writel(reg, c->gcr_reg);
447 
448 	/*
449 	 * We don't use writel() but __raw_writel() so we have to make sure
450 	 * that the DMA descriptor in coherent memory made to the main memory
451 	 * before starting the dma engine.
452 	 */
453 	__iowmb();
454 
455 	/*
456 	 * DMA transfers can take at least 200ms to complete with USB mass
457 	 * storage connected. To prevent autosuspend timeouts, we must use
458 	 * pm_runtime_get/put() when chan_busy[] is modified. This will get
459 	 * cleared in desc_to_chan() or cppi41_stop_chan() depending on the
460 	 * outcome of the transfer.
461 	 */
462 	pm_runtime_get(cdd->ddev.dev);
463 
464 	desc_phys = lower_32_bits(c->desc_phys);
465 	desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
466 	WARN_ON(cdd->chan_busy[desc_num]);
467 	cdd->chan_busy[desc_num] = c;
468 
469 	reg = (sizeof(struct cppi41_desc) - 24) / 4;
470 	reg |= desc_phys;
471 	cppi_writel(reg, cdd->qmgr_mem + QMGR_QUEUE_D(c->q_num));
472 }
473 
474 /*
475  * Caller must hold cdd->lock to prevent push_desc_queue()
476  * getting called out of order. We have both cppi41_dma_issue_pending()
477  * and cppi41_runtime_resume() call this function.
478  */
479 static void cppi41_run_queue(struct cppi41_dd *cdd)
480 {
481 	struct cppi41_channel *c, *_c;
482 
483 	list_for_each_entry_safe(c, _c, &cdd->pending, node) {
484 		push_desc_queue(c);
485 		list_del(&c->node);
486 	}
487 }
488 
489 static void cppi41_dma_issue_pending(struct dma_chan *chan)
490 {
491 	struct cppi41_channel *c = to_cpp41_chan(chan);
492 	struct cppi41_dd *cdd = c->cdd;
493 	unsigned long flags;
494 	int error;
495 
496 	error = pm_runtime_get(cdd->ddev.dev);
497 	if ((error != -EINPROGRESS) && error < 0) {
498 		pm_runtime_put_noidle(cdd->ddev.dev);
499 		dev_err(cdd->ddev.dev, "Failed to pm_runtime_get: %i\n",
500 			error);
501 
502 		return;
503 	}
504 
505 	spin_lock_irqsave(&cdd->lock, flags);
506 	list_add_tail(&c->node, &cdd->pending);
507 	if (!cdd->is_suspended)
508 		cppi41_run_queue(cdd);
509 	spin_unlock_irqrestore(&cdd->lock, flags);
510 
511 	pm_runtime_mark_last_busy(cdd->ddev.dev);
512 	pm_runtime_put_autosuspend(cdd->ddev.dev);
513 }
514 
515 static u32 get_host_pd0(u32 length)
516 {
517 	u32 reg;
518 
519 	reg = DESC_TYPE_HOST << DESC_TYPE;
520 	reg |= length;
521 
522 	return reg;
523 }
524 
525 static u32 get_host_pd1(struct cppi41_channel *c)
526 {
527 	u32 reg;
528 
529 	reg = 0;
530 
531 	return reg;
532 }
533 
534 static u32 get_host_pd2(struct cppi41_channel *c)
535 {
536 	u32 reg;
537 
538 	reg = DESC_TYPE_USB;
539 	reg |= c->q_comp_num;
540 
541 	return reg;
542 }
543 
544 static u32 get_host_pd3(u32 length)
545 {
546 	u32 reg;
547 
548 	/* PD3 = packet size */
549 	reg = length;
550 
551 	return reg;
552 }
553 
554 static u32 get_host_pd6(u32 length)
555 {
556 	u32 reg;
557 
558 	/* PD6 buffer size */
559 	reg = DESC_PD_COMPLETE;
560 	reg |= length;
561 
562 	return reg;
563 }
564 
565 static u32 get_host_pd4_or_7(u32 addr)
566 {
567 	u32 reg;
568 
569 	reg = addr;
570 
571 	return reg;
572 }
573 
574 static u32 get_host_pd5(void)
575 {
576 	u32 reg;
577 
578 	reg = 0;
579 
580 	return reg;
581 }
582 
583 static struct dma_async_tx_descriptor *cppi41_dma_prep_slave_sg(
584 	struct dma_chan *chan, struct scatterlist *sgl, unsigned sg_len,
585 	enum dma_transfer_direction dir, unsigned long tx_flags, void *context)
586 {
587 	struct cppi41_channel *c = to_cpp41_chan(chan);
588 	struct cppi41_desc *d;
589 	struct scatterlist *sg;
590 	unsigned int i;
591 
592 	d = c->desc;
593 	for_each_sg(sgl, sg, sg_len, i) {
594 		u32 addr;
595 		u32 len;
596 
597 		/* We need to use more than one desc once musb supports sg */
598 		addr = lower_32_bits(sg_dma_address(sg));
599 		len = sg_dma_len(sg);
600 
601 		d->pd0 = get_host_pd0(len);
602 		d->pd1 = get_host_pd1(c);
603 		d->pd2 = get_host_pd2(c);
604 		d->pd3 = get_host_pd3(len);
605 		d->pd4 = get_host_pd4_or_7(addr);
606 		d->pd5 = get_host_pd5();
607 		d->pd6 = get_host_pd6(len);
608 		d->pd7 = get_host_pd4_or_7(addr);
609 
610 		d++;
611 	}
612 
613 	return &c->txd;
614 }
615 
616 static void cppi41_compute_td_desc(struct cppi41_desc *d)
617 {
618 	d->pd0 = DESC_TYPE_TEARD << DESC_TYPE;
619 }
620 
621 static int cppi41_tear_down_chan(struct cppi41_channel *c)
622 {
623 	struct dmaengine_result abort_result;
624 	struct cppi41_dd *cdd = c->cdd;
625 	struct cppi41_desc *td;
626 	u32 reg;
627 	u32 desc_phys;
628 	u32 td_desc_phys;
629 
630 	td = cdd->cd;
631 	td += cdd->first_td_desc;
632 
633 	td_desc_phys = cdd->descs_phys;
634 	td_desc_phys += cdd->first_td_desc * sizeof(struct cppi41_desc);
635 
636 	if (!c->td_queued) {
637 		cppi41_compute_td_desc(td);
638 		__iowmb();
639 
640 		reg = (sizeof(struct cppi41_desc) - 24) / 4;
641 		reg |= td_desc_phys;
642 		cppi_writel(reg, cdd->qmgr_mem +
643 				QMGR_QUEUE_D(cdd->td_queue.submit));
644 
645 		reg = GCR_CHAN_ENABLE;
646 		if (!c->is_tx) {
647 			reg |= GCR_STARV_RETRY;
648 			reg |= GCR_DESC_TYPE_HOST;
649 			reg |= cdd->td_queue.complete;
650 		}
651 		reg |= GCR_TEARDOWN;
652 		cppi_writel(reg, c->gcr_reg);
653 		c->td_queued = 1;
654 		c->td_retry = 500;
655 	}
656 
657 	if (!c->td_seen || !c->td_desc_seen) {
658 
659 		desc_phys = cppi41_pop_desc(cdd, cdd->td_queue.complete);
660 		if (!desc_phys && c->is_tx)
661 			desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
662 
663 		if (desc_phys == c->desc_phys) {
664 			c->td_desc_seen = 1;
665 
666 		} else if (desc_phys == td_desc_phys) {
667 			u32 pd0;
668 
669 			__iormb();
670 			pd0 = td->pd0;
671 			WARN_ON((pd0 >> DESC_TYPE) != DESC_TYPE_TEARD);
672 			WARN_ON(!c->is_tx && !(pd0 & TD_DESC_IS_RX));
673 			WARN_ON((pd0 & 0x1f) != c->port_num);
674 			c->td_seen = 1;
675 		} else if (desc_phys) {
676 			WARN_ON_ONCE(1);
677 		}
678 	}
679 	c->td_retry--;
680 	/*
681 	 * If the TX descriptor / channel is in use, the caller needs to poke
682 	 * his TD bit multiple times. After that he hardware releases the
683 	 * transfer descriptor followed by TD descriptor. Waiting seems not to
684 	 * cause any difference.
685 	 * RX seems to be thrown out right away. However once the TearDown
686 	 * descriptor gets through we are done. If we have seens the transfer
687 	 * descriptor before the TD we fetch it from enqueue, it has to be
688 	 * there waiting for us.
689 	 */
690 	if (!c->td_seen && c->td_retry) {
691 		udelay(1);
692 		return -EAGAIN;
693 	}
694 	WARN_ON(!c->td_retry);
695 
696 	if (!c->td_desc_seen) {
697 		desc_phys = cppi41_pop_desc(cdd, c->q_num);
698 		if (!desc_phys)
699 			desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
700 		WARN_ON(!desc_phys);
701 	}
702 
703 	c->td_queued = 0;
704 	c->td_seen = 0;
705 	c->td_desc_seen = 0;
706 	cppi_writel(0, c->gcr_reg);
707 
708 	/* Invoke the callback to do the necessary clean-up */
709 	abort_result.result = DMA_TRANS_ABORTED;
710 	dma_cookie_complete(&c->txd);
711 	dmaengine_desc_get_callback_invoke(&c->txd, &abort_result);
712 
713 	return 0;
714 }
715 
716 static int cppi41_stop_chan(struct dma_chan *chan)
717 {
718 	struct cppi41_channel *c = to_cpp41_chan(chan);
719 	struct cppi41_dd *cdd = c->cdd;
720 	u32 desc_num;
721 	u32 desc_phys;
722 	int ret;
723 
724 	desc_phys = lower_32_bits(c->desc_phys);
725 	desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
726 	if (!cdd->chan_busy[desc_num]) {
727 		struct cppi41_channel *cc, *_ct;
728 
729 		/*
730 		 * channels might still be in the pendling list if
731 		 * cppi41_dma_issue_pending() is called after
732 		 * cppi41_runtime_suspend() is called
733 		 */
734 		list_for_each_entry_safe(cc, _ct, &cdd->pending, node) {
735 			if (cc != c)
736 				continue;
737 			list_del(&cc->node);
738 			break;
739 		}
740 		return 0;
741 	}
742 
743 	ret = cppi41_tear_down_chan(c);
744 	if (ret)
745 		return ret;
746 
747 	WARN_ON(!cdd->chan_busy[desc_num]);
748 	cdd->chan_busy[desc_num] = NULL;
749 
750 	/* Usecount for chan_busy[], paired with push_desc_queue() */
751 	pm_runtime_put(cdd->ddev.dev);
752 
753 	return 0;
754 }
755 
756 static int cppi41_add_chans(struct device *dev, struct cppi41_dd *cdd)
757 {
758 	struct cppi41_channel *cchan, *chans;
759 	int i;
760 	u32 n_chans = cdd->n_chans;
761 
762 	/*
763 	 * The channels can only be used as TX or as RX. So we add twice
764 	 * that much dma channels because USB can only do RX or TX.
765 	 */
766 	n_chans *= 2;
767 
768 	chans = devm_kcalloc(dev, n_chans, sizeof(*chans), GFP_KERNEL);
769 	if (!chans)
770 		return -ENOMEM;
771 
772 	for (i = 0; i < n_chans; i++) {
773 		cchan = &chans[i];
774 
775 		cchan->cdd = cdd;
776 		if (i & 1) {
777 			cchan->gcr_reg = cdd->ctrl_mem + DMA_TXGCR(i >> 1);
778 			cchan->is_tx = 1;
779 		} else {
780 			cchan->gcr_reg = cdd->ctrl_mem + DMA_RXGCR(i >> 1);
781 			cchan->is_tx = 0;
782 		}
783 		cchan->port_num = i >> 1;
784 		cchan->desc = &cdd->cd[i];
785 		cchan->desc_phys = cdd->descs_phys;
786 		cchan->desc_phys += i * sizeof(struct cppi41_desc);
787 		cchan->chan.device = &cdd->ddev;
788 		list_add_tail(&cchan->chan.device_node, &cdd->ddev.channels);
789 	}
790 	cdd->first_td_desc = n_chans;
791 
792 	return 0;
793 }
794 
795 static void purge_descs(struct device *dev, struct cppi41_dd *cdd)
796 {
797 	unsigned int mem_decs;
798 	int i;
799 
800 	mem_decs = ALLOC_DECS_NUM * sizeof(struct cppi41_desc);
801 
802 	for (i = 0; i < DESCS_AREAS; i++) {
803 
804 		cppi_writel(0, cdd->qmgr_mem + QMGR_MEMBASE(i));
805 		cppi_writel(0, cdd->qmgr_mem + QMGR_MEMCTRL(i));
806 
807 		dma_free_coherent(dev, mem_decs, cdd->cd,
808 				cdd->descs_phys);
809 	}
810 }
811 
812 static void disable_sched(struct cppi41_dd *cdd)
813 {
814 	cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
815 }
816 
817 static void deinit_cppi41(struct device *dev, struct cppi41_dd *cdd)
818 {
819 	disable_sched(cdd);
820 
821 	purge_descs(dev, cdd);
822 
823 	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
824 	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
825 	dma_free_coherent(dev, QMGR_SCRATCH_SIZE, cdd->qmgr_scratch,
826 			cdd->scratch_phys);
827 }
828 
829 static int init_descs(struct device *dev, struct cppi41_dd *cdd)
830 {
831 	unsigned int desc_size;
832 	unsigned int mem_decs;
833 	int i;
834 	u32 reg;
835 	u32 idx;
836 
837 	BUILD_BUG_ON(sizeof(struct cppi41_desc) &
838 			(sizeof(struct cppi41_desc) - 1));
839 	BUILD_BUG_ON(sizeof(struct cppi41_desc) < 32);
840 	BUILD_BUG_ON(ALLOC_DECS_NUM < 32);
841 
842 	desc_size = sizeof(struct cppi41_desc);
843 	mem_decs = ALLOC_DECS_NUM * desc_size;
844 
845 	idx = 0;
846 	for (i = 0; i < DESCS_AREAS; i++) {
847 
848 		reg = idx << QMGR_MEMCTRL_IDX_SH;
849 		reg |= (ilog2(desc_size) - 5) << QMGR_MEMCTRL_DESC_SH;
850 		reg |= ilog2(ALLOC_DECS_NUM) - 5;
851 
852 		BUILD_BUG_ON(DESCS_AREAS != 1);
853 		cdd->cd = dma_alloc_coherent(dev, mem_decs,
854 				&cdd->descs_phys, GFP_KERNEL);
855 		if (!cdd->cd)
856 			return -ENOMEM;
857 
858 		cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
859 		cppi_writel(reg, cdd->qmgr_mem + QMGR_MEMCTRL(i));
860 
861 		idx += ALLOC_DECS_NUM;
862 	}
863 	return 0;
864 }
865 
866 static void init_sched(struct cppi41_dd *cdd)
867 {
868 	unsigned ch;
869 	unsigned word;
870 	u32 reg;
871 
872 	word = 0;
873 	cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
874 	for (ch = 0; ch < cdd->n_chans; ch += 2) {
875 
876 		reg = SCHED_ENTRY0_CHAN(ch);
877 		reg |= SCHED_ENTRY1_CHAN(ch) | SCHED_ENTRY1_IS_RX;
878 
879 		reg |= SCHED_ENTRY2_CHAN(ch + 1);
880 		reg |= SCHED_ENTRY3_CHAN(ch + 1) | SCHED_ENTRY3_IS_RX;
881 		cppi_writel(reg, cdd->sched_mem + DMA_SCHED_WORD(word));
882 		word++;
883 	}
884 	reg = cdd->n_chans * 2 - 1;
885 	reg |= DMA_SCHED_CTRL_EN;
886 	cppi_writel(reg, cdd->sched_mem + DMA_SCHED_CTRL);
887 }
888 
889 static int init_cppi41(struct device *dev, struct cppi41_dd *cdd)
890 {
891 	int ret;
892 
893 	BUILD_BUG_ON(QMGR_SCRATCH_SIZE > ((1 << 14) - 1));
894 	cdd->qmgr_scratch = dma_alloc_coherent(dev, QMGR_SCRATCH_SIZE,
895 			&cdd->scratch_phys, GFP_KERNEL);
896 	if (!cdd->qmgr_scratch)
897 		return -ENOMEM;
898 
899 	cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
900 	cppi_writel(TOTAL_DESCS_NUM, cdd->qmgr_mem + QMGR_LRAM_SIZE);
901 	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
902 
903 	ret = init_descs(dev, cdd);
904 	if (ret)
905 		goto err_td;
906 
907 	cppi_writel(cdd->td_queue.submit, cdd->ctrl_mem + DMA_TDFDQ);
908 	init_sched(cdd);
909 
910 	return 0;
911 err_td:
912 	deinit_cppi41(dev, cdd);
913 	return ret;
914 }
915 
916 static struct platform_driver cpp41_dma_driver;
917 /*
918  * The param format is:
919  * X Y
920  * X: Port
921  * Y: 0 = RX else TX
922  */
923 #define INFO_PORT	0
924 #define INFO_IS_TX	1
925 
926 static bool cpp41_dma_filter_fn(struct dma_chan *chan, void *param)
927 {
928 	struct cppi41_channel *cchan;
929 	struct cppi41_dd *cdd;
930 	const struct chan_queues *queues;
931 	u32 *num = param;
932 
933 	if (chan->device->dev->driver != &cpp41_dma_driver.driver)
934 		return false;
935 
936 	cchan = to_cpp41_chan(chan);
937 
938 	if (cchan->port_num != num[INFO_PORT])
939 		return false;
940 
941 	if (cchan->is_tx && !num[INFO_IS_TX])
942 		return false;
943 	cdd = cchan->cdd;
944 	if (cchan->is_tx)
945 		queues = cdd->queues_tx;
946 	else
947 		queues = cdd->queues_rx;
948 
949 	BUILD_BUG_ON(ARRAY_SIZE(am335x_usb_queues_rx) !=
950 		     ARRAY_SIZE(am335x_usb_queues_tx));
951 	if (WARN_ON(cchan->port_num >= ARRAY_SIZE(am335x_usb_queues_rx)))
952 		return false;
953 
954 	cchan->q_num = queues[cchan->port_num].submit;
955 	cchan->q_comp_num = queues[cchan->port_num].complete;
956 	return true;
957 }
958 
959 static struct of_dma_filter_info cpp41_dma_info = {
960 	.filter_fn = cpp41_dma_filter_fn,
961 };
962 
963 static struct dma_chan *cppi41_dma_xlate(struct of_phandle_args *dma_spec,
964 		struct of_dma *ofdma)
965 {
966 	int count = dma_spec->args_count;
967 	struct of_dma_filter_info *info = ofdma->of_dma_data;
968 
969 	if (!info || !info->filter_fn)
970 		return NULL;
971 
972 	if (count != 2)
973 		return NULL;
974 
975 	return dma_request_channel(info->dma_cap, info->filter_fn,
976 			&dma_spec->args[0]);
977 }
978 
979 static const struct cppi_glue_infos am335x_usb_infos = {
980 	.queues_rx = am335x_usb_queues_rx,
981 	.queues_tx = am335x_usb_queues_tx,
982 	.td_queue = { .submit = 31, .complete = 0 },
983 	.first_completion_queue = 93,
984 	.qmgr_num_pend = 5,
985 };
986 
987 static const struct cppi_glue_infos da8xx_usb_infos = {
988 	.queues_rx = da8xx_usb_queues_rx,
989 	.queues_tx = da8xx_usb_queues_tx,
990 	.td_queue = { .submit = 31, .complete = 0 },
991 	.first_completion_queue = 24,
992 	.qmgr_num_pend = 2,
993 };
994 
995 static const struct of_device_id cppi41_dma_ids[] = {
996 	{ .compatible = "ti,am3359-cppi41", .data = &am335x_usb_infos},
997 	{ .compatible = "ti,da830-cppi41", .data = &da8xx_usb_infos},
998 	{},
999 };
1000 MODULE_DEVICE_TABLE(of, cppi41_dma_ids);
1001 
1002 static const struct cppi_glue_infos *get_glue_info(struct device *dev)
1003 {
1004 	const struct of_device_id *of_id;
1005 
1006 	of_id = of_match_node(cppi41_dma_ids, dev->of_node);
1007 	if (!of_id)
1008 		return NULL;
1009 	return of_id->data;
1010 }
1011 
1012 #define CPPI41_DMA_BUSWIDTHS	(BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
1013 				BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
1014 				BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
1015 				BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
1016 
1017 static int cppi41_dma_probe(struct platform_device *pdev)
1018 {
1019 	struct cppi41_dd *cdd;
1020 	struct device *dev = &pdev->dev;
1021 	const struct cppi_glue_infos *glue_info;
1022 	struct resource *mem;
1023 	int index;
1024 	int irq;
1025 	int ret;
1026 
1027 	glue_info = get_glue_info(dev);
1028 	if (!glue_info)
1029 		return -EINVAL;
1030 
1031 	cdd = devm_kzalloc(&pdev->dev, sizeof(*cdd), GFP_KERNEL);
1032 	if (!cdd)
1033 		return -ENOMEM;
1034 
1035 	dma_cap_set(DMA_SLAVE, cdd->ddev.cap_mask);
1036 	cdd->ddev.device_alloc_chan_resources = cppi41_dma_alloc_chan_resources;
1037 	cdd->ddev.device_free_chan_resources = cppi41_dma_free_chan_resources;
1038 	cdd->ddev.device_tx_status = cppi41_dma_tx_status;
1039 	cdd->ddev.device_issue_pending = cppi41_dma_issue_pending;
1040 	cdd->ddev.device_prep_slave_sg = cppi41_dma_prep_slave_sg;
1041 	cdd->ddev.device_terminate_all = cppi41_stop_chan;
1042 	cdd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1043 	cdd->ddev.src_addr_widths = CPPI41_DMA_BUSWIDTHS;
1044 	cdd->ddev.dst_addr_widths = CPPI41_DMA_BUSWIDTHS;
1045 	cdd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1046 	cdd->ddev.dev = dev;
1047 	INIT_LIST_HEAD(&cdd->ddev.channels);
1048 	cpp41_dma_info.dma_cap = cdd->ddev.cap_mask;
1049 
1050 	index = of_property_match_string(dev->of_node,
1051 					 "reg-names", "controller");
1052 	if (index < 0)
1053 		return index;
1054 
1055 	mem = platform_get_resource(pdev, IORESOURCE_MEM, index);
1056 	cdd->ctrl_mem = devm_ioremap_resource(dev, mem);
1057 	if (IS_ERR(cdd->ctrl_mem))
1058 		return PTR_ERR(cdd->ctrl_mem);
1059 
1060 	mem = platform_get_resource(pdev, IORESOURCE_MEM, index + 1);
1061 	cdd->sched_mem = devm_ioremap_resource(dev, mem);
1062 	if (IS_ERR(cdd->sched_mem))
1063 		return PTR_ERR(cdd->sched_mem);
1064 
1065 	mem = platform_get_resource(pdev, IORESOURCE_MEM, index + 2);
1066 	cdd->qmgr_mem = devm_ioremap_resource(dev, mem);
1067 	if (IS_ERR(cdd->qmgr_mem))
1068 		return PTR_ERR(cdd->qmgr_mem);
1069 
1070 	spin_lock_init(&cdd->lock);
1071 	INIT_LIST_HEAD(&cdd->pending);
1072 
1073 	platform_set_drvdata(pdev, cdd);
1074 
1075 	pm_runtime_enable(dev);
1076 	pm_runtime_set_autosuspend_delay(dev, 100);
1077 	pm_runtime_use_autosuspend(dev);
1078 	ret = pm_runtime_get_sync(dev);
1079 	if (ret < 0)
1080 		goto err_get_sync;
1081 
1082 	cdd->queues_rx = glue_info->queues_rx;
1083 	cdd->queues_tx = glue_info->queues_tx;
1084 	cdd->td_queue = glue_info->td_queue;
1085 	cdd->qmgr_num_pend = glue_info->qmgr_num_pend;
1086 	cdd->first_completion_queue = glue_info->first_completion_queue;
1087 
1088 	ret = of_property_read_u32(dev->of_node,
1089 				   "#dma-channels", &cdd->n_chans);
1090 	if (ret)
1091 		goto err_get_n_chans;
1092 
1093 	ret = init_cppi41(dev, cdd);
1094 	if (ret)
1095 		goto err_init_cppi;
1096 
1097 	ret = cppi41_add_chans(dev, cdd);
1098 	if (ret)
1099 		goto err_chans;
1100 
1101 	irq = irq_of_parse_and_map(dev->of_node, 0);
1102 	if (!irq) {
1103 		ret = -EINVAL;
1104 		goto err_chans;
1105 	}
1106 
1107 	ret = devm_request_irq(&pdev->dev, irq, cppi41_irq, IRQF_SHARED,
1108 			dev_name(dev), cdd);
1109 	if (ret)
1110 		goto err_chans;
1111 	cdd->irq = irq;
1112 
1113 	ret = dma_async_device_register(&cdd->ddev);
1114 	if (ret)
1115 		goto err_chans;
1116 
1117 	ret = of_dma_controller_register(dev->of_node,
1118 			cppi41_dma_xlate, &cpp41_dma_info);
1119 	if (ret)
1120 		goto err_of;
1121 
1122 	pm_runtime_mark_last_busy(dev);
1123 	pm_runtime_put_autosuspend(dev);
1124 
1125 	return 0;
1126 err_of:
1127 	dma_async_device_unregister(&cdd->ddev);
1128 err_chans:
1129 	deinit_cppi41(dev, cdd);
1130 err_init_cppi:
1131 	pm_runtime_dont_use_autosuspend(dev);
1132 err_get_n_chans:
1133 err_get_sync:
1134 	pm_runtime_put_sync(dev);
1135 	pm_runtime_disable(dev);
1136 	return ret;
1137 }
1138 
1139 static int cppi41_dma_remove(struct platform_device *pdev)
1140 {
1141 	struct cppi41_dd *cdd = platform_get_drvdata(pdev);
1142 	int error;
1143 
1144 	error = pm_runtime_get_sync(&pdev->dev);
1145 	if (error < 0)
1146 		dev_err(&pdev->dev, "%s could not pm_runtime_get: %i\n",
1147 			__func__, error);
1148 	of_dma_controller_free(pdev->dev.of_node);
1149 	dma_async_device_unregister(&cdd->ddev);
1150 
1151 	devm_free_irq(&pdev->dev, cdd->irq, cdd);
1152 	deinit_cppi41(&pdev->dev, cdd);
1153 	pm_runtime_dont_use_autosuspend(&pdev->dev);
1154 	pm_runtime_put_sync(&pdev->dev);
1155 	pm_runtime_disable(&pdev->dev);
1156 	return 0;
1157 }
1158 
1159 static int __maybe_unused cppi41_suspend(struct device *dev)
1160 {
1161 	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1162 
1163 	cdd->dma_tdfdq = cppi_readl(cdd->ctrl_mem + DMA_TDFDQ);
1164 	disable_sched(cdd);
1165 
1166 	return 0;
1167 }
1168 
1169 static int __maybe_unused cppi41_resume(struct device *dev)
1170 {
1171 	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1172 	struct cppi41_channel *c;
1173 	int i;
1174 
1175 	for (i = 0; i < DESCS_AREAS; i++)
1176 		cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
1177 
1178 	list_for_each_entry(c, &cdd->ddev.channels, chan.device_node)
1179 		if (!c->is_tx)
1180 			cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
1181 
1182 	init_sched(cdd);
1183 
1184 	cppi_writel(cdd->dma_tdfdq, cdd->ctrl_mem + DMA_TDFDQ);
1185 	cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
1186 	cppi_writel(QMGR_SCRATCH_SIZE, cdd->qmgr_mem + QMGR_LRAM_SIZE);
1187 	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
1188 
1189 	return 0;
1190 }
1191 
1192 static int __maybe_unused cppi41_runtime_suspend(struct device *dev)
1193 {
1194 	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1195 	unsigned long flags;
1196 
1197 	spin_lock_irqsave(&cdd->lock, flags);
1198 	cdd->is_suspended = true;
1199 	WARN_ON(!list_empty(&cdd->pending));
1200 	spin_unlock_irqrestore(&cdd->lock, flags);
1201 
1202 	return 0;
1203 }
1204 
1205 static int __maybe_unused cppi41_runtime_resume(struct device *dev)
1206 {
1207 	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1208 	unsigned long flags;
1209 
1210 	spin_lock_irqsave(&cdd->lock, flags);
1211 	cdd->is_suspended = false;
1212 	cppi41_run_queue(cdd);
1213 	spin_unlock_irqrestore(&cdd->lock, flags);
1214 
1215 	return 0;
1216 }
1217 
1218 static const struct dev_pm_ops cppi41_pm_ops = {
1219 	SET_LATE_SYSTEM_SLEEP_PM_OPS(cppi41_suspend, cppi41_resume)
1220 	SET_RUNTIME_PM_OPS(cppi41_runtime_suspend,
1221 			   cppi41_runtime_resume,
1222 			   NULL)
1223 };
1224 
1225 static struct platform_driver cpp41_dma_driver = {
1226 	.probe  = cppi41_dma_probe,
1227 	.remove = cppi41_dma_remove,
1228 	.driver = {
1229 		.name = "cppi41-dma-engine",
1230 		.pm = &cppi41_pm_ops,
1231 		.of_match_table = of_match_ptr(cppi41_dma_ids),
1232 	},
1233 };
1234 
1235 module_platform_driver(cpp41_dma_driver);
1236 MODULE_LICENSE("GPL");
1237 MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
1238