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
85 struct 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
107 struct 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
118 struct chan_queues {
119 u16 submit;
120 u16 complete;
121 };
122
123 struct 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
155 static 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
191 static 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
227 static 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
234 static 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
241 struct 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
to_cpp41_chan(struct dma_chan * c)249 static struct cppi41_channel *to_cpp41_chan(struct dma_chan *c)
250 {
251 return container_of(c, struct cppi41_channel, chan);
252 }
253
desc_to_chan(struct cppi41_dd * cdd,u32 desc)254 static 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
cppi_writel(u32 val,void * __iomem * mem)278 static void cppi_writel(u32 val, void *__iomem *mem)
279 {
280 __raw_writel(val, mem);
281 }
282
cppi_readl(void * __iomem * mem)283 static u32 cppi_readl(void *__iomem *mem)
284 {
285 return __raw_readl(mem);
286 }
287
pd_trans_len(u32 val)288 static u32 pd_trans_len(u32 val)
289 {
290 return val & ((1 << (DESC_LENGTH_BITS_NUM + 1)) - 1);
291 }
292
cppi41_pop_desc(struct cppi41_dd * cdd,unsigned queue_num)293 static 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
cppi41_irq(int irq,void * data)302 static 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
cppi41_tx_submit(struct dma_async_tx_descriptor * tx)362 static 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
cppi41_dma_alloc_chan_resources(struct dma_chan * chan)371 static 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
cppi41_dma_free_chan_resources(struct dma_chan * chan)399 static 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
cppi41_dma_tx_status(struct dma_chan * chan,dma_cookie_t cookie,struct dma_tx_state * txstate)418 static 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
push_desc_queue(struct cppi41_channel * c)431 static 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 */
cppi41_run_queue(struct cppi41_dd * cdd)480 static 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
cppi41_dma_issue_pending(struct dma_chan * chan)490 static 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
get_host_pd0(u32 length)516 static 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
get_host_pd1(struct cppi41_channel * c)526 static u32 get_host_pd1(struct cppi41_channel *c)
527 {
528 u32 reg;
529
530 reg = 0;
531
532 return reg;
533 }
534
get_host_pd2(struct cppi41_channel * c)535 static 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
get_host_pd3(u32 length)545 static u32 get_host_pd3(u32 length)
546 {
547 u32 reg;
548
549 /* PD3 = packet size */
550 reg = length;
551
552 return reg;
553 }
554
get_host_pd6(u32 length)555 static 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
get_host_pd4_or_7(u32 addr)566 static u32 get_host_pd4_or_7(u32 addr)
567 {
568 u32 reg;
569
570 reg = addr;
571
572 return reg;
573 }
574
get_host_pd5(void)575 static u32 get_host_pd5(void)
576 {
577 u32 reg;
578
579 reg = 0;
580
581 return reg;
582 }
583
cppi41_dma_prep_slave_sg(struct dma_chan * chan,struct scatterlist * sgl,unsigned sg_len,enum dma_transfer_direction dir,unsigned long tx_flags,void * context)584 static 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
629 err_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
cppi41_compute_td_desc(struct cppi41_desc * d)636 static void cppi41_compute_td_desc(struct cppi41_desc *d)
637 {
638 d->pd0 = DESC_TYPE_TEARD << DESC_TYPE;
639 }
640
cppi41_tear_down_chan(struct cppi41_channel * c)641 static 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
cppi41_stop_chan(struct dma_chan * chan)736 static 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
cppi41_add_chans(struct device * dev,struct cppi41_dd * cdd)776 static 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
purge_descs(struct device * dev,struct cppi41_dd * cdd)815 static 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
disable_sched(struct cppi41_dd * cdd)832 static void disable_sched(struct cppi41_dd *cdd)
833 {
834 cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
835 }
836
deinit_cppi41(struct device * dev,struct cppi41_dd * cdd)837 static 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
init_descs(struct device * dev,struct cppi41_dd * cdd)849 static 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
init_sched(struct cppi41_dd * cdd)886 static 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
init_cppi41(struct device * dev,struct cppi41_dd * cdd)909 static 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;
931 err_td:
932 deinit_cppi41(dev, cdd);
933 return ret;
934 }
935
936 static 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
cpp41_dma_filter_fn(struct dma_chan * chan,void * param)946 static 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
979 static struct of_dma_filter_info cpp41_dma_info = {
980 .filter_fn = cpp41_dma_filter_fn,
981 };
982
cppi41_dma_xlate(struct of_phandle_args * dma_spec,struct of_dma * ofdma)983 static 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
999 static 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
1007 static 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
1015 static 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 };
1020 MODULE_DEVICE_TABLE(of, cppi41_dma_ids);
1021
get_glue_info(struct device * dev)1022 static 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
cppi41_dma_probe(struct platform_device * pdev)1037 static 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;
1146 err_of:
1147 dma_async_device_unregister(&cdd->ddev);
1148 err_chans:
1149 deinit_cppi41(dev, cdd);
1150 err_init_cppi:
1151 pm_runtime_dont_use_autosuspend(dev);
1152 err_get_n_chans:
1153 err_get_sync:
1154 pm_runtime_put_sync(dev);
1155 pm_runtime_disable(dev);
1156 return ret;
1157 }
1158
cppi41_dma_remove(struct platform_device * pdev)1159 static 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
cppi41_suspend(struct device * dev)1178 static 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
cppi41_resume(struct device * dev)1188 static 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
cppi41_runtime_suspend(struct device * dev)1211 static 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
cppi41_runtime_resume(struct device * dev)1224 static 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
1237 static 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
1244 static 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
1254 module_platform_driver(cpp41_dma_driver);
1255 MODULE_DESCRIPTION("Texas Instruments CPPI 4.1 DMA support");
1256 MODULE_LICENSE("GPL");
1257 MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
1258