1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/delay.h>
3#include <linux/dmaengine.h>
4#include <linux/dma-mapping.h>
5#include <linux/platform_device.h>
6#include <linux/module.h>
7#include <linux/of.h>
8#include <linux/slab.h>
9#include <linux/of_dma.h>
10#include <linux/of_irq.h>
11#include <linux/dmapool.h>
12#include <linux/interrupt.h>
13#include <linux/of_address.h>
14#include <linux/pm_runtime.h>
15#include "../dmaengine.h"
16
17#define DESC_TYPE	27
18#define DESC_TYPE_HOST	0x10
19#define DESC_TYPE_TEARD	0x13
20
21#define TD_DESC_IS_RX	(1 << 16)
22#define TD_DESC_DMA_NUM	10
23
24#define DESC_LENGTH_BITS_NUM	21
25
26#define DESC_TYPE_USB	(5 << 26)
27#define DESC_PD_COMPLETE	(1 << 31)
28
29/* DMA engine */
30#define DMA_TDFDQ	4
31#define DMA_TXGCR(x)	(0x800 + (x) * 0x20)
32#define DMA_RXGCR(x)	(0x808 + (x) * 0x20)
33#define RXHPCRA0		4
34
35#define GCR_CHAN_ENABLE		(1 << 31)
36#define GCR_TEARDOWN		(1 << 30)
37#define GCR_STARV_RETRY		(1 << 24)
38#define GCR_DESC_TYPE_HOST	(1 << 14)
39
40/* DMA scheduler */
41#define DMA_SCHED_CTRL		0
42#define DMA_SCHED_CTRL_EN	(1 << 31)
43#define DMA_SCHED_WORD(x)	((x) * 4 + 0x800)
44
45#define SCHED_ENTRY0_CHAN(x)	((x) << 0)
46#define SCHED_ENTRY0_IS_RX	(1 << 7)
47
48#define SCHED_ENTRY1_CHAN(x)	((x) << 8)
49#define SCHED_ENTRY1_IS_RX	(1 << 15)
50
51#define SCHED_ENTRY2_CHAN(x)	((x) << 16)
52#define SCHED_ENTRY2_IS_RX	(1 << 23)
53
54#define SCHED_ENTRY3_CHAN(x)	((x) << 24)
55#define SCHED_ENTRY3_IS_RX	(1 << 31)
56
57/* Queue manager */
58/* 4 KiB of memory for descriptors, 2 for each endpoint */
59#define ALLOC_DECS_NUM		128
60#define DESCS_AREAS		1
61#define TOTAL_DESCS_NUM		(ALLOC_DECS_NUM * DESCS_AREAS)
62#define QMGR_SCRATCH_SIZE	(TOTAL_DESCS_NUM * 4)
63
64#define QMGR_LRAM0_BASE		0x80
65#define QMGR_LRAM_SIZE		0x84
66#define QMGR_LRAM1_BASE		0x88
67#define QMGR_MEMBASE(x)		(0x1000 + (x) * 0x10)
68#define QMGR_MEMCTRL(x)		(0x1004 + (x) * 0x10)
69#define QMGR_MEMCTRL_IDX_SH	16
70#define QMGR_MEMCTRL_DESC_SH	8
71
72#define QMGR_PEND(x)	(0x90 + (x) * 4)
73
74#define QMGR_PENDING_SLOT_Q(x)	(x / 32)
75#define QMGR_PENDING_BIT_Q(x)	(x % 32)
76
77#define QMGR_QUEUE_A(n)	(0x2000 + (n) * 0x10)
78#define QMGR_QUEUE_B(n)	(0x2004 + (n) * 0x10)
79#define QMGR_QUEUE_C(n)	(0x2008 + (n) * 0x10)
80#define QMGR_QUEUE_D(n)	(0x200c + (n) * 0x10)
81
82/* Packet Descriptor */
83#define PD2_ZERO_LENGTH		(1 << 19)
84
85struct cppi41_channel {
86	struct dma_chan chan;
87	struct dma_async_tx_descriptor txd;
88	struct cppi41_dd *cdd;
89	struct cppi41_desc *desc;
90	dma_addr_t desc_phys;
91	void __iomem *gcr_reg;
92	int is_tx;
93	u32 residue;
94
95	unsigned int q_num;
96	unsigned int q_comp_num;
97	unsigned int port_num;
98
99	unsigned td_retry;
100	unsigned td_queued:1;
101	unsigned td_seen:1;
102	unsigned td_desc_seen:1;
103
104	struct list_head node;		/* Node for pending list */
105};
106
107struct cppi41_desc {
108	u32 pd0;
109	u32 pd1;
110	u32 pd2;
111	u32 pd3;
112	u32 pd4;
113	u32 pd5;
114	u32 pd6;
115	u32 pd7;
116} __aligned(32);
117
118struct chan_queues {
119	u16 submit;
120	u16 complete;
121};
122
123struct cppi41_dd {
124	struct dma_device ddev;
125
126	void *qmgr_scratch;
127	dma_addr_t scratch_phys;
128
129	struct cppi41_desc *cd;
130	dma_addr_t descs_phys;
131	u32 first_td_desc;
132	struct cppi41_channel *chan_busy[ALLOC_DECS_NUM];
133
134	void __iomem *ctrl_mem;
135	void __iomem *sched_mem;
136	void __iomem *qmgr_mem;
137	unsigned int irq;
138	const struct chan_queues *queues_rx;
139	const struct chan_queues *queues_tx;
140	struct chan_queues td_queue;
141	u16 first_completion_queue;
142	u16 qmgr_num_pend;
143	u32 n_chans;
144	u8 platform;
145
146	struct list_head pending;	/* Pending queued transfers */
147	spinlock_t lock;		/* Lock for pending list */
148
149	/* context for suspend/resume */
150	unsigned int dma_tdfdq;
151
152	bool is_suspended;
153};
154
155static struct chan_queues am335x_usb_queues_tx[] = {
156	/* USB0 ENDP 1 */
157	[ 0] = { .submit = 32, .complete =  93},
158	[ 1] = { .submit = 34, .complete =  94},
159	[ 2] = { .submit = 36, .complete =  95},
160	[ 3] = { .submit = 38, .complete =  96},
161	[ 4] = { .submit = 40, .complete =  97},
162	[ 5] = { .submit = 42, .complete =  98},
163	[ 6] = { .submit = 44, .complete =  99},
164	[ 7] = { .submit = 46, .complete = 100},
165	[ 8] = { .submit = 48, .complete = 101},
166	[ 9] = { .submit = 50, .complete = 102},
167	[10] = { .submit = 52, .complete = 103},
168	[11] = { .submit = 54, .complete = 104},
169	[12] = { .submit = 56, .complete = 105},
170	[13] = { .submit = 58, .complete = 106},
171	[14] = { .submit = 60, .complete = 107},
172
173	/* USB1 ENDP1 */
174	[15] = { .submit = 62, .complete = 125},
175	[16] = { .submit = 64, .complete = 126},
176	[17] = { .submit = 66, .complete = 127},
177	[18] = { .submit = 68, .complete = 128},
178	[19] = { .submit = 70, .complete = 129},
179	[20] = { .submit = 72, .complete = 130},
180	[21] = { .submit = 74, .complete = 131},
181	[22] = { .submit = 76, .complete = 132},
182	[23] = { .submit = 78, .complete = 133},
183	[24] = { .submit = 80, .complete = 134},
184	[25] = { .submit = 82, .complete = 135},
185	[26] = { .submit = 84, .complete = 136},
186	[27] = { .submit = 86, .complete = 137},
187	[28] = { .submit = 88, .complete = 138},
188	[29] = { .submit = 90, .complete = 139},
189};
190
191static const struct chan_queues am335x_usb_queues_rx[] = {
192	/* USB0 ENDP 1 */
193	[ 0] = { .submit =  1, .complete = 109},
194	[ 1] = { .submit =  2, .complete = 110},
195	[ 2] = { .submit =  3, .complete = 111},
196	[ 3] = { .submit =  4, .complete = 112},
197	[ 4] = { .submit =  5, .complete = 113},
198	[ 5] = { .submit =  6, .complete = 114},
199	[ 6] = { .submit =  7, .complete = 115},
200	[ 7] = { .submit =  8, .complete = 116},
201	[ 8] = { .submit =  9, .complete = 117},
202	[ 9] = { .submit = 10, .complete = 118},
203	[10] = { .submit = 11, .complete = 119},
204	[11] = { .submit = 12, .complete = 120},
205	[12] = { .submit = 13, .complete = 121},
206	[13] = { .submit = 14, .complete = 122},
207	[14] = { .submit = 15, .complete = 123},
208
209	/* USB1 ENDP 1 */
210	[15] = { .submit = 16, .complete = 141},
211	[16] = { .submit = 17, .complete = 142},
212	[17] = { .submit = 18, .complete = 143},
213	[18] = { .submit = 19, .complete = 144},
214	[19] = { .submit = 20, .complete = 145},
215	[20] = { .submit = 21, .complete = 146},
216	[21] = { .submit = 22, .complete = 147},
217	[22] = { .submit = 23, .complete = 148},
218	[23] = { .submit = 24, .complete = 149},
219	[24] = { .submit = 25, .complete = 150},
220	[25] = { .submit = 26, .complete = 151},
221	[26] = { .submit = 27, .complete = 152},
222	[27] = { .submit = 28, .complete = 153},
223	[28] = { .submit = 29, .complete = 154},
224	[29] = { .submit = 30, .complete = 155},
225};
226
227static const struct chan_queues da8xx_usb_queues_tx[] = {
228	[0] = { .submit =  16, .complete = 24},
229	[1] = { .submit =  18, .complete = 24},
230	[2] = { .submit =  20, .complete = 24},
231	[3] = { .submit =  22, .complete = 24},
232};
233
234static const struct chan_queues da8xx_usb_queues_rx[] = {
235	[0] = { .submit =  1, .complete = 26},
236	[1] = { .submit =  3, .complete = 26},
237	[2] = { .submit =  5, .complete = 26},
238	[3] = { .submit =  7, .complete = 26},
239};
240
241struct cppi_glue_infos {
242	const struct chan_queues *queues_rx;
243	const struct chan_queues *queues_tx;
244	struct chan_queues td_queue;
245	u16 first_completion_queue;
246	u16 qmgr_num_pend;
247};
248
249static struct cppi41_channel *to_cpp41_chan(struct dma_chan *c)
250{
251	return container_of(c, struct cppi41_channel, chan);
252}
253
254static struct cppi41_channel *desc_to_chan(struct cppi41_dd *cdd, u32 desc)
255{
256	struct cppi41_channel *c;
257	u32 descs_size;
258	u32 desc_num;
259
260	descs_size = sizeof(struct cppi41_desc) * ALLOC_DECS_NUM;
261
262	if (!((desc >= cdd->descs_phys) &&
263			(desc < (cdd->descs_phys + descs_size)))) {
264		return NULL;
265	}
266
267	desc_num = (desc - cdd->descs_phys) / sizeof(struct cppi41_desc);
268	BUG_ON(desc_num >= ALLOC_DECS_NUM);
269	c = cdd->chan_busy[desc_num];
270	cdd->chan_busy[desc_num] = NULL;
271
272	/* Usecount for chan_busy[], paired with push_desc_queue() */
273	pm_runtime_put(cdd->ddev.dev);
274
275	return c;
276}
277
278static void cppi_writel(u32 val, void *__iomem *mem)
279{
280	__raw_writel(val, mem);
281}
282
283static u32 cppi_readl(void *__iomem *mem)
284{
285	return __raw_readl(mem);
286}
287
288static u32 pd_trans_len(u32 val)
289{
290	return val & ((1 << (DESC_LENGTH_BITS_NUM + 1)) - 1);
291}
292
293static u32 cppi41_pop_desc(struct cppi41_dd *cdd, unsigned queue_num)
294{
295	u32 desc;
296
297	desc = cppi_readl(cdd->qmgr_mem + QMGR_QUEUE_D(queue_num));
298	desc &= ~0x1f;
299	return desc;
300}
301
302static irqreturn_t cppi41_irq(int irq, void *data)
303{
304	struct cppi41_dd *cdd = data;
305	u16 first_completion_queue = cdd->first_completion_queue;
306	u16 qmgr_num_pend = cdd->qmgr_num_pend;
307	struct cppi41_channel *c;
308	int i;
309
310	for (i = QMGR_PENDING_SLOT_Q(first_completion_queue); i < qmgr_num_pend;
311			i++) {
312		u32 val;
313		u32 q_num;
314
315		val = cppi_readl(cdd->qmgr_mem + QMGR_PEND(i));
316		if (i == QMGR_PENDING_SLOT_Q(first_completion_queue) && val) {
317			u32 mask;
318			/* set corresponding bit for completion Q 93 */
319			mask = 1 << QMGR_PENDING_BIT_Q(first_completion_queue);
320			/* not set all bits for queues less than Q 93 */
321			mask--;
322			/* now invert and keep only Q 93+ set */
323			val &= ~mask;
324		}
325
326		if (val)
327			__iormb();
328
329		while (val) {
330			u32 desc, len;
331
332			/*
333			 * This should never trigger, see the comments in
334			 * push_desc_queue()
335			 */
336			WARN_ON(cdd->is_suspended);
337
338			q_num = __fls(val);
339			val &= ~(1 << q_num);
340			q_num += 32 * i;
341			desc = cppi41_pop_desc(cdd, q_num);
342			c = desc_to_chan(cdd, desc);
343			if (WARN_ON(!c)) {
344				pr_err("%s() q %d desc %08x\n", __func__,
345						q_num, desc);
346				continue;
347			}
348
349			if (c->desc->pd2 & PD2_ZERO_LENGTH)
350				len = 0;
351			else
352				len = pd_trans_len(c->desc->pd0);
353
354			c->residue = pd_trans_len(c->desc->pd6) - len;
355			dma_cookie_complete(&c->txd);
356			dmaengine_desc_get_callback_invoke(&c->txd, NULL);
357		}
358	}
359	return IRQ_HANDLED;
360}
361
362static dma_cookie_t cppi41_tx_submit(struct dma_async_tx_descriptor *tx)
363{
364	dma_cookie_t cookie;
365
366	cookie = dma_cookie_assign(tx);
367
368	return cookie;
369}
370
371static int cppi41_dma_alloc_chan_resources(struct dma_chan *chan)
372{
373	struct cppi41_channel *c = to_cpp41_chan(chan);
374	struct cppi41_dd *cdd = c->cdd;
375	int error;
376
377	error = pm_runtime_get_sync(cdd->ddev.dev);
378	if (error < 0) {
379		dev_err(cdd->ddev.dev, "%s pm runtime get: %i\n",
380			__func__, error);
381		pm_runtime_put_noidle(cdd->ddev.dev);
382
383		return error;
384	}
385
386	dma_cookie_init(chan);
387	dma_async_tx_descriptor_init(&c->txd, chan);
388	c->txd.tx_submit = cppi41_tx_submit;
389
390	if (!c->is_tx)
391		cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
392
393	pm_runtime_mark_last_busy(cdd->ddev.dev);
394	pm_runtime_put_autosuspend(cdd->ddev.dev);
395
396	return 0;
397}
398
399static void cppi41_dma_free_chan_resources(struct dma_chan *chan)
400{
401	struct cppi41_channel *c = to_cpp41_chan(chan);
402	struct cppi41_dd *cdd = c->cdd;
403	int error;
404
405	error = pm_runtime_get_sync(cdd->ddev.dev);
406	if (error < 0) {
407		pm_runtime_put_noidle(cdd->ddev.dev);
408
409		return;
410	}
411
412	WARN_ON(!list_empty(&cdd->pending));
413
414	pm_runtime_mark_last_busy(cdd->ddev.dev);
415	pm_runtime_put_autosuspend(cdd->ddev.dev);
416}
417
418static enum dma_status cppi41_dma_tx_status(struct dma_chan *chan,
419	dma_cookie_t cookie, struct dma_tx_state *txstate)
420{
421	struct cppi41_channel *c = to_cpp41_chan(chan);
422	enum dma_status ret;
423
424	ret = dma_cookie_status(chan, cookie, txstate);
425
426	dma_set_residue(txstate, c->residue);
427
428	return ret;
429}
430
431static void push_desc_queue(struct cppi41_channel *c)
432{
433	struct cppi41_dd *cdd = c->cdd;
434	u32 desc_num;
435	u32 desc_phys;
436	u32 reg;
437
438	c->residue = 0;
439
440	reg = GCR_CHAN_ENABLE;
441	if (!c->is_tx) {
442		reg |= GCR_STARV_RETRY;
443		reg |= GCR_DESC_TYPE_HOST;
444		reg |= c->q_comp_num;
445	}
446
447	cppi_writel(reg, c->gcr_reg);
448
449	/*
450	 * We don't use writel() but __raw_writel() so we have to make sure
451	 * that the DMA descriptor in coherent memory made to the main memory
452	 * before starting the dma engine.
453	 */
454	__iowmb();
455
456	/*
457	 * DMA transfers can take at least 200ms to complete with USB mass
458	 * storage connected. To prevent autosuspend timeouts, we must use
459	 * pm_runtime_get/put() when chan_busy[] is modified. This will get
460	 * cleared in desc_to_chan() or cppi41_stop_chan() depending on the
461	 * outcome of the transfer.
462	 */
463	pm_runtime_get(cdd->ddev.dev);
464
465	desc_phys = lower_32_bits(c->desc_phys);
466	desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
467	WARN_ON(cdd->chan_busy[desc_num]);
468	cdd->chan_busy[desc_num] = c;
469
470	reg = (sizeof(struct cppi41_desc) - 24) / 4;
471	reg |= desc_phys;
472	cppi_writel(reg, cdd->qmgr_mem + QMGR_QUEUE_D(c->q_num));
473}
474
475/*
476 * Caller must hold cdd->lock to prevent push_desc_queue()
477 * getting called out of order. We have both cppi41_dma_issue_pending()
478 * and cppi41_runtime_resume() call this function.
479 */
480static void cppi41_run_queue(struct cppi41_dd *cdd)
481{
482	struct cppi41_channel *c, *_c;
483
484	list_for_each_entry_safe(c, _c, &cdd->pending, node) {
485		push_desc_queue(c);
486		list_del(&c->node);
487	}
488}
489
490static void cppi41_dma_issue_pending(struct dma_chan *chan)
491{
492	struct cppi41_channel *c = to_cpp41_chan(chan);
493	struct cppi41_dd *cdd = c->cdd;
494	unsigned long flags;
495	int error;
496
497	error = pm_runtime_get(cdd->ddev.dev);
498	if ((error != -EINPROGRESS) && error < 0) {
499		pm_runtime_put_noidle(cdd->ddev.dev);
500		dev_err(cdd->ddev.dev, "Failed to pm_runtime_get: %i\n",
501			error);
502
503		return;
504	}
505
506	spin_lock_irqsave(&cdd->lock, flags);
507	list_add_tail(&c->node, &cdd->pending);
508	if (!cdd->is_suspended)
509		cppi41_run_queue(cdd);
510	spin_unlock_irqrestore(&cdd->lock, flags);
511
512	pm_runtime_mark_last_busy(cdd->ddev.dev);
513	pm_runtime_put_autosuspend(cdd->ddev.dev);
514}
515
516static u32 get_host_pd0(u32 length)
517{
518	u32 reg;
519
520	reg = DESC_TYPE_HOST << DESC_TYPE;
521	reg |= length;
522
523	return reg;
524}
525
526static u32 get_host_pd1(struct cppi41_channel *c)
527{
528	u32 reg;
529
530	reg = 0;
531
532	return reg;
533}
534
535static u32 get_host_pd2(struct cppi41_channel *c)
536{
537	u32 reg;
538
539	reg = DESC_TYPE_USB;
540	reg |= c->q_comp_num;
541
542	return reg;
543}
544
545static u32 get_host_pd3(u32 length)
546{
547	u32 reg;
548
549	/* PD3 = packet size */
550	reg = length;
551
552	return reg;
553}
554
555static u32 get_host_pd6(u32 length)
556{
557	u32 reg;
558
559	/* PD6 buffer size */
560	reg = DESC_PD_COMPLETE;
561	reg |= length;
562
563	return reg;
564}
565
566static u32 get_host_pd4_or_7(u32 addr)
567{
568	u32 reg;
569
570	reg = addr;
571
572	return reg;
573}
574
575static u32 get_host_pd5(void)
576{
577	u32 reg;
578
579	reg = 0;
580
581	return reg;
582}
583
584static struct dma_async_tx_descriptor *cppi41_dma_prep_slave_sg(
585	struct dma_chan *chan, struct scatterlist *sgl, unsigned sg_len,
586	enum dma_transfer_direction dir, unsigned long tx_flags, void *context)
587{
588	struct cppi41_channel *c = to_cpp41_chan(chan);
589	struct dma_async_tx_descriptor *txd = NULL;
590	struct cppi41_dd *cdd = c->cdd;
591	struct cppi41_desc *d;
592	struct scatterlist *sg;
593	unsigned int i;
594	int error;
595
596	error = pm_runtime_get(cdd->ddev.dev);
597	if (error < 0) {
598		pm_runtime_put_noidle(cdd->ddev.dev);
599
600		return NULL;
601	}
602
603	if (cdd->is_suspended)
604		goto err_out_not_ready;
605
606	d = c->desc;
607	for_each_sg(sgl, sg, sg_len, i) {
608		u32 addr;
609		u32 len;
610
611		/* We need to use more than one desc once musb supports sg */
612		addr = lower_32_bits(sg_dma_address(sg));
613		len = sg_dma_len(sg);
614
615		d->pd0 = get_host_pd0(len);
616		d->pd1 = get_host_pd1(c);
617		d->pd2 = get_host_pd2(c);
618		d->pd3 = get_host_pd3(len);
619		d->pd4 = get_host_pd4_or_7(addr);
620		d->pd5 = get_host_pd5();
621		d->pd6 = get_host_pd6(len);
622		d->pd7 = get_host_pd4_or_7(addr);
623
624		d++;
625	}
626
627	txd = &c->txd;
628
629err_out_not_ready:
630	pm_runtime_mark_last_busy(cdd->ddev.dev);
631	pm_runtime_put_autosuspend(cdd->ddev.dev);
632
633	return txd;
634}
635
636static void cppi41_compute_td_desc(struct cppi41_desc *d)
637{
638	d->pd0 = DESC_TYPE_TEARD << DESC_TYPE;
639}
640
641static int cppi41_tear_down_chan(struct cppi41_channel *c)
642{
643	struct dmaengine_result abort_result;
644	struct cppi41_dd *cdd = c->cdd;
645	struct cppi41_desc *td;
646	u32 reg;
647	u32 desc_phys;
648	u32 td_desc_phys;
649
650	td = cdd->cd;
651	td += cdd->first_td_desc;
652
653	td_desc_phys = cdd->descs_phys;
654	td_desc_phys += cdd->first_td_desc * sizeof(struct cppi41_desc);
655
656	if (!c->td_queued) {
657		cppi41_compute_td_desc(td);
658		__iowmb();
659
660		reg = (sizeof(struct cppi41_desc) - 24) / 4;
661		reg |= td_desc_phys;
662		cppi_writel(reg, cdd->qmgr_mem +
663				QMGR_QUEUE_D(cdd->td_queue.submit));
664
665		reg = GCR_CHAN_ENABLE;
666		if (!c->is_tx) {
667			reg |= GCR_STARV_RETRY;
668			reg |= GCR_DESC_TYPE_HOST;
669			reg |= cdd->td_queue.complete;
670		}
671		reg |= GCR_TEARDOWN;
672		cppi_writel(reg, c->gcr_reg);
673		c->td_queued = 1;
674		c->td_retry = 500;
675	}
676
677	if (!c->td_seen || !c->td_desc_seen) {
678
679		desc_phys = cppi41_pop_desc(cdd, cdd->td_queue.complete);
680		if (!desc_phys && c->is_tx)
681			desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
682
683		if (desc_phys == c->desc_phys) {
684			c->td_desc_seen = 1;
685
686		} else if (desc_phys == td_desc_phys) {
687			u32 pd0;
688
689			__iormb();
690			pd0 = td->pd0;
691			WARN_ON((pd0 >> DESC_TYPE) != DESC_TYPE_TEARD);
692			WARN_ON(!c->is_tx && !(pd0 & TD_DESC_IS_RX));
693			WARN_ON((pd0 & 0x1f) != c->port_num);
694			c->td_seen = 1;
695		} else if (desc_phys) {
696			WARN_ON_ONCE(1);
697		}
698	}
699	c->td_retry--;
700	/*
701	 * If the TX descriptor / channel is in use, the caller needs to poke
702	 * his TD bit multiple times. After that he hardware releases the
703	 * transfer descriptor followed by TD descriptor. Waiting seems not to
704	 * cause any difference.
705	 * RX seems to be thrown out right away. However once the TearDown
706	 * descriptor gets through we are done. If we have seen the transfer
707	 * descriptor before the TD we fetch it from enqueue, it has to be
708	 * there waiting for us.
709	 */
710	if (!c->td_seen && c->td_retry) {
711		udelay(1);
712		return -EAGAIN;
713	}
714	WARN_ON(!c->td_retry);
715
716	if (!c->td_desc_seen) {
717		desc_phys = cppi41_pop_desc(cdd, c->q_num);
718		if (!desc_phys)
719			desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
720		WARN_ON(!desc_phys);
721	}
722
723	c->td_queued = 0;
724	c->td_seen = 0;
725	c->td_desc_seen = 0;
726	cppi_writel(0, c->gcr_reg);
727
728	/* Invoke the callback to do the necessary clean-up */
729	abort_result.result = DMA_TRANS_ABORTED;
730	dma_cookie_complete(&c->txd);
731	dmaengine_desc_get_callback_invoke(&c->txd, &abort_result);
732
733	return 0;
734}
735
736static int cppi41_stop_chan(struct dma_chan *chan)
737{
738	struct cppi41_channel *c = to_cpp41_chan(chan);
739	struct cppi41_dd *cdd = c->cdd;
740	u32 desc_num;
741	u32 desc_phys;
742	int ret;
743
744	desc_phys = lower_32_bits(c->desc_phys);
745	desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
746	if (!cdd->chan_busy[desc_num]) {
747		struct cppi41_channel *cc, *_ct;
748
749		/*
750		 * channels might still be in the pending list if
751		 * cppi41_dma_issue_pending() is called after
752		 * cppi41_runtime_suspend() is called
753		 */
754		list_for_each_entry_safe(cc, _ct, &cdd->pending, node) {
755			if (cc != c)
756				continue;
757			list_del(&cc->node);
758			break;
759		}
760		return 0;
761	}
762
763	ret = cppi41_tear_down_chan(c);
764	if (ret)
765		return ret;
766
767	WARN_ON(!cdd->chan_busy[desc_num]);
768	cdd->chan_busy[desc_num] = NULL;
769
770	/* Usecount for chan_busy[], paired with push_desc_queue() */
771	pm_runtime_put(cdd->ddev.dev);
772
773	return 0;
774}
775
776static int cppi41_add_chans(struct device *dev, struct cppi41_dd *cdd)
777{
778	struct cppi41_channel *cchan, *chans;
779	int i;
780	u32 n_chans = cdd->n_chans;
781
782	/*
783	 * The channels can only be used as TX or as RX. So we add twice
784	 * that much dma channels because USB can only do RX or TX.
785	 */
786	n_chans *= 2;
787
788	chans = devm_kcalloc(dev, n_chans, sizeof(*chans), GFP_KERNEL);
789	if (!chans)
790		return -ENOMEM;
791
792	for (i = 0; i < n_chans; i++) {
793		cchan = &chans[i];
794
795		cchan->cdd = cdd;
796		if (i & 1) {
797			cchan->gcr_reg = cdd->ctrl_mem + DMA_TXGCR(i >> 1);
798			cchan->is_tx = 1;
799		} else {
800			cchan->gcr_reg = cdd->ctrl_mem + DMA_RXGCR(i >> 1);
801			cchan->is_tx = 0;
802		}
803		cchan->port_num = i >> 1;
804		cchan->desc = &cdd->cd[i];
805		cchan->desc_phys = cdd->descs_phys;
806		cchan->desc_phys += i * sizeof(struct cppi41_desc);
807		cchan->chan.device = &cdd->ddev;
808		list_add_tail(&cchan->chan.device_node, &cdd->ddev.channels);
809	}
810	cdd->first_td_desc = n_chans;
811
812	return 0;
813}
814
815static void purge_descs(struct device *dev, struct cppi41_dd *cdd)
816{
817	unsigned int mem_decs;
818	int i;
819
820	mem_decs = ALLOC_DECS_NUM * sizeof(struct cppi41_desc);
821
822	for (i = 0; i < DESCS_AREAS; i++) {
823
824		cppi_writel(0, cdd->qmgr_mem + QMGR_MEMBASE(i));
825		cppi_writel(0, cdd->qmgr_mem + QMGR_MEMCTRL(i));
826
827		dma_free_coherent(dev, mem_decs, cdd->cd,
828				cdd->descs_phys);
829	}
830}
831
832static void disable_sched(struct cppi41_dd *cdd)
833{
834	cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
835}
836
837static void deinit_cppi41(struct device *dev, struct cppi41_dd *cdd)
838{
839	disable_sched(cdd);
840
841	purge_descs(dev, cdd);
842
843	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
844	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
845	dma_free_coherent(dev, QMGR_SCRATCH_SIZE, cdd->qmgr_scratch,
846			cdd->scratch_phys);
847}
848
849static int init_descs(struct device *dev, struct cppi41_dd *cdd)
850{
851	unsigned int desc_size;
852	unsigned int mem_decs;
853	int i;
854	u32 reg;
855	u32 idx;
856
857	BUILD_BUG_ON(sizeof(struct cppi41_desc) &
858			(sizeof(struct cppi41_desc) - 1));
859	BUILD_BUG_ON(sizeof(struct cppi41_desc) < 32);
860	BUILD_BUG_ON(ALLOC_DECS_NUM < 32);
861
862	desc_size = sizeof(struct cppi41_desc);
863	mem_decs = ALLOC_DECS_NUM * desc_size;
864
865	idx = 0;
866	for (i = 0; i < DESCS_AREAS; i++) {
867
868		reg = idx << QMGR_MEMCTRL_IDX_SH;
869		reg |= (ilog2(desc_size) - 5) << QMGR_MEMCTRL_DESC_SH;
870		reg |= ilog2(ALLOC_DECS_NUM) - 5;
871
872		BUILD_BUG_ON(DESCS_AREAS != 1);
873		cdd->cd = dma_alloc_coherent(dev, mem_decs,
874				&cdd->descs_phys, GFP_KERNEL);
875		if (!cdd->cd)
876			return -ENOMEM;
877
878		cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
879		cppi_writel(reg, cdd->qmgr_mem + QMGR_MEMCTRL(i));
880
881		idx += ALLOC_DECS_NUM;
882	}
883	return 0;
884}
885
886static void init_sched(struct cppi41_dd *cdd)
887{
888	unsigned ch;
889	unsigned word;
890	u32 reg;
891
892	word = 0;
893	cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
894	for (ch = 0; ch < cdd->n_chans; ch += 2) {
895
896		reg = SCHED_ENTRY0_CHAN(ch);
897		reg |= SCHED_ENTRY1_CHAN(ch) | SCHED_ENTRY1_IS_RX;
898
899		reg |= SCHED_ENTRY2_CHAN(ch + 1);
900		reg |= SCHED_ENTRY3_CHAN(ch + 1) | SCHED_ENTRY3_IS_RX;
901		cppi_writel(reg, cdd->sched_mem + DMA_SCHED_WORD(word));
902		word++;
903	}
904	reg = cdd->n_chans * 2 - 1;
905	reg |= DMA_SCHED_CTRL_EN;
906	cppi_writel(reg, cdd->sched_mem + DMA_SCHED_CTRL);
907}
908
909static int init_cppi41(struct device *dev, struct cppi41_dd *cdd)
910{
911	int ret;
912
913	BUILD_BUG_ON(QMGR_SCRATCH_SIZE > ((1 << 14) - 1));
914	cdd->qmgr_scratch = dma_alloc_coherent(dev, QMGR_SCRATCH_SIZE,
915			&cdd->scratch_phys, GFP_KERNEL);
916	if (!cdd->qmgr_scratch)
917		return -ENOMEM;
918
919	cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
920	cppi_writel(TOTAL_DESCS_NUM, cdd->qmgr_mem + QMGR_LRAM_SIZE);
921	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
922
923	ret = init_descs(dev, cdd);
924	if (ret)
925		goto err_td;
926
927	cppi_writel(cdd->td_queue.submit, cdd->ctrl_mem + DMA_TDFDQ);
928	init_sched(cdd);
929
930	return 0;
931err_td:
932	deinit_cppi41(dev, cdd);
933	return ret;
934}
935
936static struct platform_driver cpp41_dma_driver;
937/*
938 * The param format is:
939 * X Y
940 * X: Port
941 * Y: 0 = RX else TX
942 */
943#define INFO_PORT	0
944#define INFO_IS_TX	1
945
946static bool cpp41_dma_filter_fn(struct dma_chan *chan, void *param)
947{
948	struct cppi41_channel *cchan;
949	struct cppi41_dd *cdd;
950	const struct chan_queues *queues;
951	u32 *num = param;
952
953	if (chan->device->dev->driver != &cpp41_dma_driver.driver)
954		return false;
955
956	cchan = to_cpp41_chan(chan);
957
958	if (cchan->port_num != num[INFO_PORT])
959		return false;
960
961	if (cchan->is_tx && !num[INFO_IS_TX])
962		return false;
963	cdd = cchan->cdd;
964	if (cchan->is_tx)
965		queues = cdd->queues_tx;
966	else
967		queues = cdd->queues_rx;
968
969	BUILD_BUG_ON(ARRAY_SIZE(am335x_usb_queues_rx) !=
970		     ARRAY_SIZE(am335x_usb_queues_tx));
971	if (WARN_ON(cchan->port_num >= ARRAY_SIZE(am335x_usb_queues_rx)))
972		return false;
973
974	cchan->q_num = queues[cchan->port_num].submit;
975	cchan->q_comp_num = queues[cchan->port_num].complete;
976	return true;
977}
978
979static struct of_dma_filter_info cpp41_dma_info = {
980	.filter_fn = cpp41_dma_filter_fn,
981};
982
983static struct dma_chan *cppi41_dma_xlate(struct of_phandle_args *dma_spec,
984		struct of_dma *ofdma)
985{
986	int count = dma_spec->args_count;
987	struct of_dma_filter_info *info = ofdma->of_dma_data;
988
989	if (!info || !info->filter_fn)
990		return NULL;
991
992	if (count != 2)
993		return NULL;
994
995	return dma_request_channel(info->dma_cap, info->filter_fn,
996			&dma_spec->args[0]);
997}
998
999static const struct cppi_glue_infos am335x_usb_infos = {
1000	.queues_rx = am335x_usb_queues_rx,
1001	.queues_tx = am335x_usb_queues_tx,
1002	.td_queue = { .submit = 31, .complete = 0 },
1003	.first_completion_queue = 93,
1004	.qmgr_num_pend = 5,
1005};
1006
1007static const struct cppi_glue_infos da8xx_usb_infos = {
1008	.queues_rx = da8xx_usb_queues_rx,
1009	.queues_tx = da8xx_usb_queues_tx,
1010	.td_queue = { .submit = 31, .complete = 0 },
1011	.first_completion_queue = 24,
1012	.qmgr_num_pend = 2,
1013};
1014
1015static const struct of_device_id cppi41_dma_ids[] = {
1016	{ .compatible = "ti,am3359-cppi41", .data = &am335x_usb_infos},
1017	{ .compatible = "ti,da830-cppi41", .data = &da8xx_usb_infos},
1018	{},
1019};
1020MODULE_DEVICE_TABLE(of, cppi41_dma_ids);
1021
1022static const struct cppi_glue_infos *get_glue_info(struct device *dev)
1023{
1024	const struct of_device_id *of_id;
1025
1026	of_id = of_match_node(cppi41_dma_ids, dev->of_node);
1027	if (!of_id)
1028		return NULL;
1029	return of_id->data;
1030}
1031
1032#define CPPI41_DMA_BUSWIDTHS	(BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
1033				BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
1034				BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
1035				BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
1036
1037static int cppi41_dma_probe(struct platform_device *pdev)
1038{
1039	struct cppi41_dd *cdd;
1040	struct device *dev = &pdev->dev;
1041	const struct cppi_glue_infos *glue_info;
1042	int index;
1043	int irq;
1044	int ret;
1045
1046	glue_info = get_glue_info(dev);
1047	if (!glue_info)
1048		return -EINVAL;
1049
1050	cdd = devm_kzalloc(&pdev->dev, sizeof(*cdd), GFP_KERNEL);
1051	if (!cdd)
1052		return -ENOMEM;
1053
1054	dma_cap_set(DMA_SLAVE, cdd->ddev.cap_mask);
1055	cdd->ddev.device_alloc_chan_resources = cppi41_dma_alloc_chan_resources;
1056	cdd->ddev.device_free_chan_resources = cppi41_dma_free_chan_resources;
1057	cdd->ddev.device_tx_status = cppi41_dma_tx_status;
1058	cdd->ddev.device_issue_pending = cppi41_dma_issue_pending;
1059	cdd->ddev.device_prep_slave_sg = cppi41_dma_prep_slave_sg;
1060	cdd->ddev.device_terminate_all = cppi41_stop_chan;
1061	cdd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1062	cdd->ddev.src_addr_widths = CPPI41_DMA_BUSWIDTHS;
1063	cdd->ddev.dst_addr_widths = CPPI41_DMA_BUSWIDTHS;
1064	cdd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1065	cdd->ddev.dev = dev;
1066	INIT_LIST_HEAD(&cdd->ddev.channels);
1067	cpp41_dma_info.dma_cap = cdd->ddev.cap_mask;
1068
1069	index = of_property_match_string(dev->of_node,
1070					 "reg-names", "controller");
1071	if (index < 0)
1072		return index;
1073
1074	cdd->ctrl_mem = devm_platform_ioremap_resource(pdev, index);
1075	if (IS_ERR(cdd->ctrl_mem))
1076		return PTR_ERR(cdd->ctrl_mem);
1077
1078	cdd->sched_mem = devm_platform_ioremap_resource(pdev, index + 1);
1079	if (IS_ERR(cdd->sched_mem))
1080		return PTR_ERR(cdd->sched_mem);
1081
1082	cdd->qmgr_mem = devm_platform_ioremap_resource(pdev, index + 2);
1083	if (IS_ERR(cdd->qmgr_mem))
1084		return PTR_ERR(cdd->qmgr_mem);
1085
1086	spin_lock_init(&cdd->lock);
1087	INIT_LIST_HEAD(&cdd->pending);
1088
1089	platform_set_drvdata(pdev, cdd);
1090
1091	pm_runtime_enable(dev);
1092	pm_runtime_set_autosuspend_delay(dev, 100);
1093	pm_runtime_use_autosuspend(dev);
1094	ret = pm_runtime_get_sync(dev);
1095	if (ret < 0)
1096		goto err_get_sync;
1097
1098	cdd->queues_rx = glue_info->queues_rx;
1099	cdd->queues_tx = glue_info->queues_tx;
1100	cdd->td_queue = glue_info->td_queue;
1101	cdd->qmgr_num_pend = glue_info->qmgr_num_pend;
1102	cdd->first_completion_queue = glue_info->first_completion_queue;
1103
1104	/* Parse new and deprecated dma-channels properties */
1105	ret = of_property_read_u32(dev->of_node,
1106				   "dma-channels", &cdd->n_chans);
1107	if (ret)
1108		ret = of_property_read_u32(dev->of_node,
1109					   "#dma-channels", &cdd->n_chans);
1110	if (ret)
1111		goto err_get_n_chans;
1112
1113	ret = init_cppi41(dev, cdd);
1114	if (ret)
1115		goto err_init_cppi;
1116
1117	ret = cppi41_add_chans(dev, cdd);
1118	if (ret)
1119		goto err_chans;
1120
1121	irq = irq_of_parse_and_map(dev->of_node, 0);
1122	if (!irq) {
1123		ret = -EINVAL;
1124		goto err_chans;
1125	}
1126
1127	ret = devm_request_irq(&pdev->dev, irq, cppi41_irq, IRQF_SHARED,
1128			dev_name(dev), cdd);
1129	if (ret)
1130		goto err_chans;
1131	cdd->irq = irq;
1132
1133	ret = dma_async_device_register(&cdd->ddev);
1134	if (ret)
1135		goto err_chans;
1136
1137	ret = of_dma_controller_register(dev->of_node,
1138			cppi41_dma_xlate, &cpp41_dma_info);
1139	if (ret)
1140		goto err_of;
1141
1142	pm_runtime_mark_last_busy(dev);
1143	pm_runtime_put_autosuspend(dev);
1144
1145	return 0;
1146err_of:
1147	dma_async_device_unregister(&cdd->ddev);
1148err_chans:
1149	deinit_cppi41(dev, cdd);
1150err_init_cppi:
1151	pm_runtime_dont_use_autosuspend(dev);
1152err_get_n_chans:
1153err_get_sync:
1154	pm_runtime_put_sync(dev);
1155	pm_runtime_disable(dev);
1156	return ret;
1157}
1158
1159static void cppi41_dma_remove(struct platform_device *pdev)
1160{
1161	struct cppi41_dd *cdd = platform_get_drvdata(pdev);
1162	int error;
1163
1164	error = pm_runtime_get_sync(&pdev->dev);
1165	if (error < 0)
1166		dev_err(&pdev->dev, "%s could not pm_runtime_get: %i\n",
1167			__func__, error);
1168	of_dma_controller_free(pdev->dev.of_node);
1169	dma_async_device_unregister(&cdd->ddev);
1170
1171	devm_free_irq(&pdev->dev, cdd->irq, cdd);
1172	deinit_cppi41(&pdev->dev, cdd);
1173	pm_runtime_dont_use_autosuspend(&pdev->dev);
1174	pm_runtime_put_sync(&pdev->dev);
1175	pm_runtime_disable(&pdev->dev);
1176}
1177
1178static int __maybe_unused cppi41_suspend(struct device *dev)
1179{
1180	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1181
1182	cdd->dma_tdfdq = cppi_readl(cdd->ctrl_mem + DMA_TDFDQ);
1183	disable_sched(cdd);
1184
1185	return 0;
1186}
1187
1188static int __maybe_unused cppi41_resume(struct device *dev)
1189{
1190	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1191	struct cppi41_channel *c;
1192	int i;
1193
1194	for (i = 0; i < DESCS_AREAS; i++)
1195		cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
1196
1197	list_for_each_entry(c, &cdd->ddev.channels, chan.device_node)
1198		if (!c->is_tx)
1199			cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
1200
1201	init_sched(cdd);
1202
1203	cppi_writel(cdd->dma_tdfdq, cdd->ctrl_mem + DMA_TDFDQ);
1204	cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
1205	cppi_writel(QMGR_SCRATCH_SIZE, cdd->qmgr_mem + QMGR_LRAM_SIZE);
1206	cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
1207
1208	return 0;
1209}
1210
1211static int __maybe_unused cppi41_runtime_suspend(struct device *dev)
1212{
1213	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1214	unsigned long flags;
1215
1216	spin_lock_irqsave(&cdd->lock, flags);
1217	cdd->is_suspended = true;
1218	WARN_ON(!list_empty(&cdd->pending));
1219	spin_unlock_irqrestore(&cdd->lock, flags);
1220
1221	return 0;
1222}
1223
1224static int __maybe_unused cppi41_runtime_resume(struct device *dev)
1225{
1226	struct cppi41_dd *cdd = dev_get_drvdata(dev);
1227	unsigned long flags;
1228
1229	spin_lock_irqsave(&cdd->lock, flags);
1230	cdd->is_suspended = false;
1231	cppi41_run_queue(cdd);
1232	spin_unlock_irqrestore(&cdd->lock, flags);
1233
1234	return 0;
1235}
1236
1237static const struct dev_pm_ops cppi41_pm_ops = {
1238	SET_LATE_SYSTEM_SLEEP_PM_OPS(cppi41_suspend, cppi41_resume)
1239	SET_RUNTIME_PM_OPS(cppi41_runtime_suspend,
1240			   cppi41_runtime_resume,
1241			   NULL)
1242};
1243
1244static struct platform_driver cpp41_dma_driver = {
1245	.probe  = cppi41_dma_probe,
1246	.remove_new = cppi41_dma_remove,
1247	.driver = {
1248		.name = "cppi41-dma-engine",
1249		.pm = &cppi41_pm_ops,
1250		.of_match_table = of_match_ptr(cppi41_dma_ids),
1251	},
1252};
1253
1254module_platform_driver(cpp41_dma_driver);
1255MODULE_LICENSE("GPL");
1256MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
1257