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dm writecache: add cond_resched to loop in persistent_memory_claim()
[linux/fpc-iii.git] / drivers / dma / ti / omap-dma.c
blob918301e1755252e22253f9e5714b3a6e6e06ee87
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * OMAP DMAengine support
4 */
5 #include <linux/cpu_pm.h>
6 #include <linux/delay.h>
7 #include <linux/dmaengine.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/dmapool.h>
10 #include <linux/err.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/list.h>
14 #include <linux/module.h>
15 #include <linux/omap-dma.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
18 #include <linux/spinlock.h>
19 #include <linux/of_dma.h>
20 #include <linux/of_device.h>
21
22 #include "../virt-dma.h"
23
24 #define OMAP_SDMA_REQUESTS 127
25 #define OMAP_SDMA_CHANNELS 32
26
27 struct omap_dma_config {
28 int lch_end;
29 unsigned int rw_priority:1;
30 unsigned int needs_busy_check:1;
31 unsigned int may_lose_context:1;
32 unsigned int needs_lch_clear:1;
33 };
34
35 struct omap_dma_context {
36 u32 irqenable_l0;
37 u32 irqenable_l1;
38 u32 ocp_sysconfig;
39 u32 gcr;
40 };
41
42 struct omap_dmadev {
43 struct dma_device ddev;
44 spinlock_t lock;
45 void __iomem *base;
46 const struct omap_dma_reg *reg_map;
47 struct omap_system_dma_plat_info *plat;
48 const struct omap_dma_config *cfg;
49 struct notifier_block nb;
50 struct omap_dma_context context;
51 int lch_count;
52 DECLARE_BITMAP(lch_bitmap, OMAP_SDMA_CHANNELS);
53 struct mutex lch_lock; /* for assigning logical channels */
54 bool legacy;
55 bool ll123_supported;
56 struct dma_pool *desc_pool;
57 unsigned dma_requests;
58 spinlock_t irq_lock;
59 uint32_t irq_enable_mask;
60 struct omap_chan **lch_map;
61 };
62
63 struct omap_chan {
64 struct virt_dma_chan vc;
65 void __iomem *channel_base;
66 const struct omap_dma_reg *reg_map;
67 uint32_t ccr;
68
69 struct dma_slave_config cfg;
70 unsigned dma_sig;
71 bool cyclic;
72 bool paused;
73 bool running;
74
75 int dma_ch;
76 struct omap_desc *desc;
77 unsigned sgidx;
78 };
79
80 #define DESC_NXT_SV_REFRESH (0x1 << 24)
81 #define DESC_NXT_SV_REUSE (0x2 << 24)
82 #define DESC_NXT_DV_REFRESH (0x1 << 26)
83 #define DESC_NXT_DV_REUSE (0x2 << 26)
84 #define DESC_NTYPE_TYPE2 (0x2 << 29)
85
86 /* Type 2 descriptor with Source or Destination address update */
87 struct omap_type2_desc {
88 uint32_t next_desc;
89 uint32_t en;
90 uint32_t addr; /* src or dst */
91 uint16_t fn;
92 uint16_t cicr;
93 int16_t cdei;
94 int16_t csei;
95 int32_t cdfi;
96 int32_t csfi;
97 } __packed;
98
99 struct omap_sg {
100 dma_addr_t addr;
101 uint32_t en; /* number of elements (24-bit) */
102 uint32_t fn; /* number of frames (16-bit) */
103 int32_t fi; /* for double indexing */
104 int16_t ei; /* for double indexing */
105
106 /* Linked list */
107 struct omap_type2_desc *t2_desc;
108 dma_addr_t t2_desc_paddr;
109 };
110
111 struct omap_desc {
112 struct virt_dma_desc vd;
113 bool using_ll;
114 enum dma_transfer_direction dir;
115 dma_addr_t dev_addr;
116 bool polled;
117
118 int32_t fi; /* for OMAP_DMA_SYNC_PACKET / double indexing */
119 int16_t ei; /* for double indexing */
120 uint8_t es; /* CSDP_DATA_TYPE_xxx */
121 uint32_t ccr; /* CCR value */
122 uint16_t clnk_ctrl; /* CLNK_CTRL value */
123 uint16_t cicr; /* CICR value */
124 uint32_t csdp; /* CSDP value */
125
126 unsigned sglen;
127 struct omap_sg sg[];
128 };
129
130 enum {
131 CAPS_0_SUPPORT_LL123 = BIT(20), /* Linked List type1/2/3 */
132 CAPS_0_SUPPORT_LL4 = BIT(21), /* Linked List type4 */
133
134 CCR_FS = BIT(5),
135 CCR_READ_PRIORITY = BIT(6),
136 CCR_ENABLE = BIT(7),
137 CCR_AUTO_INIT = BIT(8), /* OMAP1 only */
138 CCR_REPEAT = BIT(9), /* OMAP1 only */
139 CCR_OMAP31_DISABLE = BIT(10), /* OMAP1 only */
140 CCR_SUSPEND_SENSITIVE = BIT(8), /* OMAP2+ only */
141 CCR_RD_ACTIVE = BIT(9), /* OMAP2+ only */
142 CCR_WR_ACTIVE = BIT(10), /* OMAP2+ only */
143 CCR_SRC_AMODE_CONSTANT = 0 << 12,
144 CCR_SRC_AMODE_POSTINC = 1 << 12,
145 CCR_SRC_AMODE_SGLIDX = 2 << 12,
146 CCR_SRC_AMODE_DBLIDX = 3 << 12,
147 CCR_DST_AMODE_CONSTANT = 0 << 14,
148 CCR_DST_AMODE_POSTINC = 1 << 14,
149 CCR_DST_AMODE_SGLIDX = 2 << 14,
150 CCR_DST_AMODE_DBLIDX = 3 << 14,
151 CCR_CONSTANT_FILL = BIT(16),
152 CCR_TRANSPARENT_COPY = BIT(17),
153 CCR_BS = BIT(18),
154 CCR_SUPERVISOR = BIT(22),
155 CCR_PREFETCH = BIT(23),
156 CCR_TRIGGER_SRC = BIT(24),
157 CCR_BUFFERING_DISABLE = BIT(25),
158 CCR_WRITE_PRIORITY = BIT(26),
159 CCR_SYNC_ELEMENT = 0,
160 CCR_SYNC_FRAME = CCR_FS,
161 CCR_SYNC_BLOCK = CCR_BS,
162 CCR_SYNC_PACKET = CCR_BS | CCR_FS,
163
164 CSDP_DATA_TYPE_8 = 0,
165 CSDP_DATA_TYPE_16 = 1,
166 CSDP_DATA_TYPE_32 = 2,
167 CSDP_SRC_PORT_EMIFF = 0 << 2, /* OMAP1 only */
168 CSDP_SRC_PORT_EMIFS = 1 << 2, /* OMAP1 only */
169 CSDP_SRC_PORT_OCP_T1 = 2 << 2, /* OMAP1 only */
170 CSDP_SRC_PORT_TIPB = 3 << 2, /* OMAP1 only */
171 CSDP_SRC_PORT_OCP_T2 = 4 << 2, /* OMAP1 only */
172 CSDP_SRC_PORT_MPUI = 5 << 2, /* OMAP1 only */
173 CSDP_SRC_PACKED = BIT(6),
174 CSDP_SRC_BURST_1 = 0 << 7,
175 CSDP_SRC_BURST_16 = 1 << 7,
176 CSDP_SRC_BURST_32 = 2 << 7,
177 CSDP_SRC_BURST_64 = 3 << 7,
178 CSDP_DST_PORT_EMIFF = 0 << 9, /* OMAP1 only */
179 CSDP_DST_PORT_EMIFS = 1 << 9, /* OMAP1 only */
180 CSDP_DST_PORT_OCP_T1 = 2 << 9, /* OMAP1 only */
181 CSDP_DST_PORT_TIPB = 3 << 9, /* OMAP1 only */
182 CSDP_DST_PORT_OCP_T2 = 4 << 9, /* OMAP1 only */
183 CSDP_DST_PORT_MPUI = 5 << 9, /* OMAP1 only */
184 CSDP_DST_PACKED = BIT(13),
185 CSDP_DST_BURST_1 = 0 << 14,
186 CSDP_DST_BURST_16 = 1 << 14,
187 CSDP_DST_BURST_32 = 2 << 14,
188 CSDP_DST_BURST_64 = 3 << 14,
189 CSDP_WRITE_NON_POSTED = 0 << 16,
190 CSDP_WRITE_POSTED = 1 << 16,
191 CSDP_WRITE_LAST_NON_POSTED = 2 << 16,
192
193 CICR_TOUT_IE = BIT(0), /* OMAP1 only */
194 CICR_DROP_IE = BIT(1),
195 CICR_HALF_IE = BIT(2),
196 CICR_FRAME_IE = BIT(3),
197 CICR_LAST_IE = BIT(4),
198 CICR_BLOCK_IE = BIT(5),
199 CICR_PKT_IE = BIT(7), /* OMAP2+ only */
200 CICR_TRANS_ERR_IE = BIT(8), /* OMAP2+ only */
201 CICR_SUPERVISOR_ERR_IE = BIT(10), /* OMAP2+ only */
202 CICR_MISALIGNED_ERR_IE = BIT(11), /* OMAP2+ only */
203 CICR_DRAIN_IE = BIT(12), /* OMAP2+ only */
204 CICR_SUPER_BLOCK_IE = BIT(14), /* OMAP2+ only */
205
206 CLNK_CTRL_ENABLE_LNK = BIT(15),
207
208 CDP_DST_VALID_INC = 0 << 0,
209 CDP_DST_VALID_RELOAD = 1 << 0,
210 CDP_DST_VALID_REUSE = 2 << 0,
211 CDP_SRC_VALID_INC = 0 << 2,
212 CDP_SRC_VALID_RELOAD = 1 << 2,
213 CDP_SRC_VALID_REUSE = 2 << 2,
214 CDP_NTYPE_TYPE1 = 1 << 4,
215 CDP_NTYPE_TYPE2 = 2 << 4,
216 CDP_NTYPE_TYPE3 = 3 << 4,
217 CDP_TMODE_NORMAL = 0 << 8,
218 CDP_TMODE_LLIST = 1 << 8,
219 CDP_FAST = BIT(10),
220 };
221
222 static const unsigned es_bytes[] = {
223 [CSDP_DATA_TYPE_8] = 1,
224 [CSDP_DATA_TYPE_16] = 2,
225 [CSDP_DATA_TYPE_32] = 4,
226 };
227
228 static bool omap_dma_filter_fn(struct dma_chan *chan, void *param);
229 static struct of_dma_filter_info omap_dma_info = {
230 .filter_fn = omap_dma_filter_fn,
231 };
232
233 static inline struct omap_dmadev *to_omap_dma_dev(struct dma_device *d)
234 {
235 return container_of(d, struct omap_dmadev, ddev);
236 }
237
238 static inline struct omap_chan *to_omap_dma_chan(struct dma_chan *c)
239 {
240 return container_of(c, struct omap_chan, vc.chan);
241 }
242
243 static inline struct omap_desc *to_omap_dma_desc(struct dma_async_tx_descriptor *t)
244 {
245 return container_of(t, struct omap_desc, vd.tx);
246 }
247
248 static void omap_dma_desc_free(struct virt_dma_desc *vd)
249 {
250 struct omap_desc *d = to_omap_dma_desc(&vd->tx);
251
252 if (d->using_ll) {
253 struct omap_dmadev *od = to_omap_dma_dev(vd->tx.chan->device);
254 int i;
255
256 for (i = 0; i < d->sglen; i++) {
257 if (d->sg[i].t2_desc)
258 dma_pool_free(od->desc_pool, d->sg[i].t2_desc,
259 d->sg[i].t2_desc_paddr);
260 }
261 }
262
263 kfree(d);
264 }
265
266 static void omap_dma_fill_type2_desc(struct omap_desc *d, int idx,
267 enum dma_transfer_direction dir, bool last)
268 {
269 struct omap_sg *sg = &d->sg[idx];
270 struct omap_type2_desc *t2_desc = sg->t2_desc;
271
272 if (idx)
273 d->sg[idx - 1].t2_desc->next_desc = sg->t2_desc_paddr;
274 if (last)
275 t2_desc->next_desc = 0xfffffffc;
276
277 t2_desc->en = sg->en;
278 t2_desc->addr = sg->addr;
279 t2_desc->fn = sg->fn & 0xffff;
280 t2_desc->cicr = d->cicr;
281 if (!last)
282 t2_desc->cicr &= ~CICR_BLOCK_IE;
283
284 switch (dir) {
285 case DMA_DEV_TO_MEM:
286 t2_desc->cdei = sg->ei;
287 t2_desc->csei = d->ei;
288 t2_desc->cdfi = sg->fi;
289 t2_desc->csfi = d->fi;
290
291 t2_desc->en |= DESC_NXT_DV_REFRESH;
292 t2_desc->en |= DESC_NXT_SV_REUSE;
293 break;
294 case DMA_MEM_TO_DEV:
295 t2_desc->cdei = d->ei;
296 t2_desc->csei = sg->ei;
297 t2_desc->cdfi = d->fi;
298 t2_desc->csfi = sg->fi;
299
300 t2_desc->en |= DESC_NXT_SV_REFRESH;
301 t2_desc->en |= DESC_NXT_DV_REUSE;
302 break;
303 default:
304 return;
305 }
306
307 t2_desc->en |= DESC_NTYPE_TYPE2;
308 }
309
310 static void omap_dma_write(uint32_t val, unsigned type, void __iomem *addr)
311 {
312 switch (type) {
313 case OMAP_DMA_REG_16BIT:
314 writew_relaxed(val, addr);
315 break;
316 case OMAP_DMA_REG_2X16BIT:
317 writew_relaxed(val, addr);
318 writew_relaxed(val >> 16, addr + 2);
319 break;
320 case OMAP_DMA_REG_32BIT:
321 writel_relaxed(val, addr);
322 break;
323 default:
324 WARN_ON(1);
325 }
326 }
327
328 static unsigned omap_dma_read(unsigned type, void __iomem *addr)
329 {
330 unsigned val;
331
332 switch (type) {
333 case OMAP_DMA_REG_16BIT:
334 val = readw_relaxed(addr);
335 break;
336 case OMAP_DMA_REG_2X16BIT:
337 val = readw_relaxed(addr);
338 val |= readw_relaxed(addr + 2) << 16;
339 break;
340 case OMAP_DMA_REG_32BIT:
341 val = readl_relaxed(addr);
342 break;
343 default:
344 WARN_ON(1);
345 val = 0;
346 }
347
348 return val;
349 }
350
351 static void omap_dma_glbl_write(struct omap_dmadev *od, unsigned reg, unsigned val)
352 {
353 const struct omap_dma_reg *r = od->reg_map + reg;
354
355 WARN_ON(r->stride);
356
357 omap_dma_write(val, r->type, od->base + r->offset);
358 }
359
360 static unsigned omap_dma_glbl_read(struct omap_dmadev *od, unsigned reg)
361 {
362 const struct omap_dma_reg *r = od->reg_map + reg;
363
364 WARN_ON(r->stride);
365
366 return omap_dma_read(r->type, od->base + r->offset);
367 }
368
369 static void omap_dma_chan_write(struct omap_chan *c, unsigned reg, unsigned val)
370 {
371 const struct omap_dma_reg *r = c->reg_map + reg;
372
373 omap_dma_write(val, r->type, c->channel_base + r->offset);
374 }
375
376 static unsigned omap_dma_chan_read(struct omap_chan *c, unsigned reg)
377 {
378 const struct omap_dma_reg *r = c->reg_map + reg;
379
380 return omap_dma_read(r->type, c->channel_base + r->offset);
381 }
382
383 static void omap_dma_clear_csr(struct omap_chan *c)
384 {
385 if (dma_omap1())
386 omap_dma_chan_read(c, CSR);
387 else
388 omap_dma_chan_write(c, CSR, ~0);
389 }
390
391 static unsigned omap_dma_get_csr(struct omap_chan *c)
392 {
393 unsigned val = omap_dma_chan_read(c, CSR);
394
395 if (!dma_omap1())
396 omap_dma_chan_write(c, CSR, val);
397
398 return val;
399 }
400
401 static void omap_dma_clear_lch(struct omap_dmadev *od, int lch)
402 {
403 struct omap_chan *c;
404 int i;
405
406 c = od->lch_map[lch];
407 if (!c)
408 return;
409
410 for (i = CSDP; i <= od->cfg->lch_end; i++)
411 omap_dma_chan_write(c, i, 0);
412 }
413
414 static void omap_dma_assign(struct omap_dmadev *od, struct omap_chan *c,
415 unsigned lch)
416 {
417 c->channel_base = od->base + od->plat->channel_stride * lch;
418
419 od->lch_map[lch] = c;
420 }
421
422 static void omap_dma_start(struct omap_chan *c, struct omap_desc *d)
423 {
424 struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
425 uint16_t cicr = d->cicr;
426
427 if (__dma_omap15xx(od->plat->dma_attr))
428 omap_dma_chan_write(c, CPC, 0);
429 else
430 omap_dma_chan_write(c, CDAC, 0);
431
432 omap_dma_clear_csr(c);
433
434 if (d->using_ll) {
435 uint32_t cdp = CDP_TMODE_LLIST | CDP_NTYPE_TYPE2 | CDP_FAST;
436
437 if (d->dir == DMA_DEV_TO_MEM)
438 cdp |= (CDP_DST_VALID_RELOAD | CDP_SRC_VALID_REUSE);
439 else
440 cdp |= (CDP_DST_VALID_REUSE | CDP_SRC_VALID_RELOAD);
441 omap_dma_chan_write(c, CDP, cdp);
442
443 omap_dma_chan_write(c, CNDP, d->sg[0].t2_desc_paddr);
444 omap_dma_chan_write(c, CCDN, 0);
445 omap_dma_chan_write(c, CCFN, 0xffff);
446 omap_dma_chan_write(c, CCEN, 0xffffff);
447
448 cicr &= ~CICR_BLOCK_IE;
449 } else if (od->ll123_supported) {
450 omap_dma_chan_write(c, CDP, 0);
451 }
452
453 /* Enable interrupts */
454 omap_dma_chan_write(c, CICR, cicr);
455
456 /* Enable channel */
457 omap_dma_chan_write(c, CCR, d->ccr | CCR_ENABLE);
458
459 c->running = true;
460 }
461
462 static void omap_dma_drain_chan(struct omap_chan *c)
463 {
464 int i;
465 u32 val;
466
467 /* Wait for sDMA FIFO to drain */
468 for (i = 0; ; i++) {
469 val = omap_dma_chan_read(c, CCR);
470 if (!(val & (CCR_RD_ACTIVE | CCR_WR_ACTIVE)))
471 break;
472
473 if (i > 100)
474 break;
475
476 udelay(5);
477 }
478
479 if (val & (CCR_RD_ACTIVE | CCR_WR_ACTIVE))
480 dev_err(c->vc.chan.device->dev,
481 "DMA drain did not complete on lch %d\n",
482 c->dma_ch);
483 }
484
485 static int omap_dma_stop(struct omap_chan *c)
486 {
487 struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
488 uint32_t val;
489
490 /* disable irq */
491 omap_dma_chan_write(c, CICR, 0);
492
493 omap_dma_clear_csr(c);
494
495 val = omap_dma_chan_read(c, CCR);
496 if (od->plat->errata & DMA_ERRATA_i541 && val & CCR_TRIGGER_SRC) {
497 uint32_t sysconfig;
498
499 sysconfig = omap_dma_glbl_read(od, OCP_SYSCONFIG);
500 val = sysconfig & ~DMA_SYSCONFIG_MIDLEMODE_MASK;
501 val |= DMA_SYSCONFIG_MIDLEMODE(DMA_IDLEMODE_NO_IDLE);
502 omap_dma_glbl_write(od, OCP_SYSCONFIG, val);
503
504 val = omap_dma_chan_read(c, CCR);
505 val &= ~CCR_ENABLE;
506 omap_dma_chan_write(c, CCR, val);
507
508 if (!(c->ccr & CCR_BUFFERING_DISABLE))
509 omap_dma_drain_chan(c);
510
511 omap_dma_glbl_write(od, OCP_SYSCONFIG, sysconfig);
512 } else {
513 if (!(val & CCR_ENABLE))
514 return -EINVAL;
515
516 val &= ~CCR_ENABLE;
517 omap_dma_chan_write(c, CCR, val);
518
519 if (!(c->ccr & CCR_BUFFERING_DISABLE))
520 omap_dma_drain_chan(c);
521 }
522
523 mb();
524
525 if (!__dma_omap15xx(od->plat->dma_attr) && c->cyclic) {
526 val = omap_dma_chan_read(c, CLNK_CTRL);
527
528 if (dma_omap1())
529 val |= 1 << 14; /* set the STOP_LNK bit */
530 else
531 val &= ~CLNK_CTRL_ENABLE_LNK;
532
533 omap_dma_chan_write(c, CLNK_CTRL, val);
534 }
535 c->running = false;
536 return 0;
537 }
538
539 static void omap_dma_start_sg(struct omap_chan *c, struct omap_desc *d)
540 {
541 struct omap_sg *sg = d->sg + c->sgidx;
542 unsigned cxsa, cxei, cxfi;
543
544 if (d->dir == DMA_DEV_TO_MEM || d->dir == DMA_MEM_TO_MEM) {
545 cxsa = CDSA;
546 cxei = CDEI;
547 cxfi = CDFI;
548 } else {
549 cxsa = CSSA;
550 cxei = CSEI;
551 cxfi = CSFI;
552 }
553
554 omap_dma_chan_write(c, cxsa, sg->addr);
555 omap_dma_chan_write(c, cxei, sg->ei);
556 omap_dma_chan_write(c, cxfi, sg->fi);
557 omap_dma_chan_write(c, CEN, sg->en);
558 omap_dma_chan_write(c, CFN, sg->fn);
559
560 omap_dma_start(c, d);
561 c->sgidx++;
562 }
563
564 static void omap_dma_start_desc(struct omap_chan *c)
565 {
566 struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
567 struct omap_desc *d;
568 unsigned cxsa, cxei, cxfi;
569
570 if (!vd) {
571 c->desc = NULL;
572 return;
573 }
574
575 list_del(&vd->node);
576
577 c->desc = d = to_omap_dma_desc(&vd->tx);
578 c->sgidx = 0;
579
580 /*
581 * This provides the necessary barrier to ensure data held in
582 * DMA coherent memory is visible to the DMA engine prior to
583 * the transfer starting.
584 */
585 mb();
586
587 omap_dma_chan_write(c, CCR, d->ccr);
588 if (dma_omap1())
589 omap_dma_chan_write(c, CCR2, d->ccr >> 16);
590
591 if (d->dir == DMA_DEV_TO_MEM || d->dir == DMA_MEM_TO_MEM) {
592 cxsa = CSSA;
593 cxei = CSEI;
594 cxfi = CSFI;
595 } else {
596 cxsa = CDSA;
597 cxei = CDEI;
598 cxfi = CDFI;
599 }
600
601 omap_dma_chan_write(c, cxsa, d->dev_addr);
602 omap_dma_chan_write(c, cxei, d->ei);
603 omap_dma_chan_write(c, cxfi, d->fi);
604 omap_dma_chan_write(c, CSDP, d->csdp);
605 omap_dma_chan_write(c, CLNK_CTRL, d->clnk_ctrl);
606
607 omap_dma_start_sg(c, d);
608 }
609
610 static void omap_dma_callback(int ch, u16 status, void *data)
611 {
612 struct omap_chan *c = data;
613 struct omap_desc *d;
614 unsigned long flags;
615
616 spin_lock_irqsave(&c->vc.lock, flags);
617 d = c->desc;
618 if (d) {
619 if (c->cyclic) {
620 vchan_cyclic_callback(&d->vd);
621 } else if (d->using_ll || c->sgidx == d->sglen) {
622 omap_dma_start_desc(c);
623 vchan_cookie_complete(&d->vd);
624 } else {
625 omap_dma_start_sg(c, d);
626 }
627 }
628 spin_unlock_irqrestore(&c->vc.lock, flags);
629 }
630
631 static irqreturn_t omap_dma_irq(int irq, void *devid)
632 {
633 struct omap_dmadev *od = devid;
634 unsigned status, channel;
635
636 spin_lock(&od->irq_lock);
637
638 status = omap_dma_glbl_read(od, IRQSTATUS_L1);
639 status &= od->irq_enable_mask;
640 if (status == 0) {
641 spin_unlock(&od->irq_lock);
642 return IRQ_NONE;
643 }
644
645 while ((channel = ffs(status)) != 0) {
646 unsigned mask, csr;
647 struct omap_chan *c;
648
649 channel -= 1;
650 mask = BIT(channel);
651 status &= ~mask;
652
653 c = od->lch_map[channel];
654 if (c == NULL) {
655 /* This should never happen */
656 dev_err(od->ddev.dev, "invalid channel %u\n", channel);
657 continue;
658 }
659
660 csr = omap_dma_get_csr(c);
661 omap_dma_glbl_write(od, IRQSTATUS_L1, mask);
662
663 omap_dma_callback(channel, csr, c);
664 }
665
666 spin_unlock(&od->irq_lock);
667
668 return IRQ_HANDLED;
669 }
670
671 static int omap_dma_get_lch(struct omap_dmadev *od, int *lch)
672 {
673 int channel;
674
675 mutex_lock(&od->lch_lock);
676 channel = find_first_zero_bit(od->lch_bitmap, od->lch_count);
677 if (channel >= od->lch_count)
678 goto out_busy;
679 set_bit(channel, od->lch_bitmap);
680 mutex_unlock(&od->lch_lock);
681
682 omap_dma_clear_lch(od, channel);
683 *lch = channel;
684
685 return 0;
686
687 out_busy:
688 mutex_unlock(&od->lch_lock);
689 *lch = -EINVAL;
690
691 return -EBUSY;
692 }
693
694 static void omap_dma_put_lch(struct omap_dmadev *od, int lch)
695 {
696 omap_dma_clear_lch(od, lch);
697 mutex_lock(&od->lch_lock);
698 clear_bit(lch, od->lch_bitmap);
699 mutex_unlock(&od->lch_lock);
700 }
701
702 static int omap_dma_alloc_chan_resources(struct dma_chan *chan)
703 {
704 struct omap_dmadev *od = to_omap_dma_dev(chan->device);
705 struct omap_chan *c = to_omap_dma_chan(chan);
706 struct device *dev = od->ddev.dev;
707 int ret;
708
709 if (od->legacy) {
710 ret = omap_request_dma(c->dma_sig, "DMA engine",
711 omap_dma_callback, c, &c->dma_ch);
712 } else {
713 ret = omap_dma_get_lch(od, &c->dma_ch);
714 }
715
716 dev_dbg(dev, "allocating channel %u for %u\n", c->dma_ch, c->dma_sig);
717
718 if (ret >= 0) {
719 omap_dma_assign(od, c, c->dma_ch);
720
721 if (!od->legacy) {
722 unsigned val;
723
724 spin_lock_irq(&od->irq_lock);
725 val = BIT(c->dma_ch);
726 omap_dma_glbl_write(od, IRQSTATUS_L1, val);
727 od->irq_enable_mask |= val;
728 omap_dma_glbl_write(od, IRQENABLE_L1, od->irq_enable_mask);
729
730 val = omap_dma_glbl_read(od, IRQENABLE_L0);
731 val &= ~BIT(c->dma_ch);
732 omap_dma_glbl_write(od, IRQENABLE_L0, val);
733 spin_unlock_irq(&od->irq_lock);
734 }
735 }
736
737 if (dma_omap1()) {
738 if (__dma_omap16xx(od->plat->dma_attr)) {
739 c->ccr = CCR_OMAP31_DISABLE;
740 /* Duplicate what plat-omap/dma.c does */
741 c->ccr |= c->dma_ch + 1;
742 } else {
743 c->ccr = c->dma_sig & 0x1f;
744 }
745 } else {
746 c->ccr = c->dma_sig & 0x1f;
747 c->ccr |= (c->dma_sig & ~0x1f) << 14;
748 }
749 if (od->plat->errata & DMA_ERRATA_IFRAME_BUFFERING)
750 c->ccr |= CCR_BUFFERING_DISABLE;
751
752 return ret;
753 }
754
755 static void omap_dma_free_chan_resources(struct dma_chan *chan)
756 {
757 struct omap_dmadev *od = to_omap_dma_dev(chan->device);
758 struct omap_chan *c = to_omap_dma_chan(chan);
759
760 if (!od->legacy) {
761 spin_lock_irq(&od->irq_lock);
762 od->irq_enable_mask &= ~BIT(c->dma_ch);
763 omap_dma_glbl_write(od, IRQENABLE_L1, od->irq_enable_mask);
764 spin_unlock_irq(&od->irq_lock);
765 }
766
767 c->channel_base = NULL;
768 od->lch_map[c->dma_ch] = NULL;
769 vchan_free_chan_resources(&c->vc);
770
771 if (od->legacy)
772 omap_free_dma(c->dma_ch);
773 else
774 omap_dma_put_lch(od, c->dma_ch);
775
776 dev_dbg(od->ddev.dev, "freeing channel %u used for %u\n", c->dma_ch,
777 c->dma_sig);
778 c->dma_sig = 0;
779 }
780
781 static size_t omap_dma_sg_size(struct omap_sg *sg)
782 {
783 return sg->en * sg->fn;
784 }
785
786 static size_t omap_dma_desc_size(struct omap_desc *d)
787 {
788 unsigned i;
789 size_t size;
790
791 for (size = i = 0; i < d->sglen; i++)
792 size += omap_dma_sg_size(&d->sg[i]);
793
794 return size * es_bytes[d->es];
795 }
796
797 static size_t omap_dma_desc_size_pos(struct omap_desc *d, dma_addr_t addr)
798 {
799 unsigned i;
800 size_t size, es_size = es_bytes[d->es];
801
802 for (size = i = 0; i < d->sglen; i++) {
803 size_t this_size = omap_dma_sg_size(&d->sg[i]) * es_size;
804
805 if (size)
806 size += this_size;
807 else if (addr >= d->sg[i].addr &&
808 addr < d->sg[i].addr + this_size)
809 size += d->sg[i].addr + this_size - addr;
810 }
811 return size;
812 }
813
814 /*
815 * OMAP 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is
816 * read before the DMA controller finished disabling the channel.
817 */
818 static uint32_t omap_dma_chan_read_3_3(struct omap_chan *c, unsigned reg)
819 {
820 struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
821 uint32_t val;
822
823 val = omap_dma_chan_read(c, reg);
824 if (val == 0 && od->plat->errata & DMA_ERRATA_3_3)
825 val = omap_dma_chan_read(c, reg);
826
827 return val;
828 }
829
830 static dma_addr_t omap_dma_get_src_pos(struct omap_chan *c)
831 {
832 struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
833 dma_addr_t addr, cdac;
834
835 if (__dma_omap15xx(od->plat->dma_attr)) {
836 addr = omap_dma_chan_read(c, CPC);
837 } else {
838 addr = omap_dma_chan_read_3_3(c, CSAC);
839 cdac = omap_dma_chan_read_3_3(c, CDAC);
840
841 /*
842 * CDAC == 0 indicates that the DMA transfer on the channel has
843 * not been started (no data has been transferred so far).
844 * Return the programmed source start address in this case.
845 */
846 if (cdac == 0)
847 addr = omap_dma_chan_read(c, CSSA);
848 }
849
850 if (dma_omap1())
851 addr |= omap_dma_chan_read(c, CSSA) & 0xffff0000;
852
853 return addr;
854 }
855
856 static dma_addr_t omap_dma_get_dst_pos(struct omap_chan *c)
857 {
858 struct omap_dmadev *od = to_omap_dma_dev(c->vc.chan.device);
859 dma_addr_t addr;
860
861 if (__dma_omap15xx(od->plat->dma_attr)) {
862 addr = omap_dma_chan_read(c, CPC);
863 } else {
864 addr = omap_dma_chan_read_3_3(c, CDAC);
865
866 /*
867 * CDAC == 0 indicates that the DMA transfer on the channel
868 * has not been started (no data has been transferred so
869 * far). Return the programmed destination start address in
870 * this case.
871 */
872 if (addr == 0)
873 addr = omap_dma_chan_read(c, CDSA);
874 }
875
876 if (dma_omap1())
877 addr |= omap_dma_chan_read(c, CDSA) & 0xffff0000;
878
879 return addr;
880 }
881
882 static enum dma_status omap_dma_tx_status(struct dma_chan *chan,
883 dma_cookie_t cookie, struct dma_tx_state *txstate)
884 {
885 struct omap_chan *c = to_omap_dma_chan(chan);
886 enum dma_status ret;
887 unsigned long flags;
888 struct omap_desc *d = NULL;
889
890 ret = dma_cookie_status(chan, cookie, txstate);
891 if (ret == DMA_COMPLETE)
892 return ret;
893
894 spin_lock_irqsave(&c->vc.lock, flags);
895 if (c->desc && c->desc->vd.tx.cookie == cookie)
896 d = c->desc;
897
898 if (!txstate)
899 goto out;
900
901 if (d) {
902 dma_addr_t pos;
903
904 if (d->dir == DMA_MEM_TO_DEV)
905 pos = omap_dma_get_src_pos(c);
906 else if (d->dir == DMA_DEV_TO_MEM || d->dir == DMA_MEM_TO_MEM)
907 pos = omap_dma_get_dst_pos(c);
908 else
909 pos = 0;
910
911 txstate->residue = omap_dma_desc_size_pos(d, pos);
912 } else {
913 struct virt_dma_desc *vd = vchan_find_desc(&c->vc, cookie);
914
915 if (vd)
916 txstate->residue = omap_dma_desc_size(
917 to_omap_dma_desc(&vd->tx));
918 else
919 txstate->residue = 0;
920 }
921
922 out:
923 if (ret == DMA_IN_PROGRESS && c->paused) {
924 ret = DMA_PAUSED;
925 } else if (d && d->polled && c->running) {
926 uint32_t ccr = omap_dma_chan_read(c, CCR);
927 /*
928 * The channel is no longer active, set the return value
929 * accordingly and mark it as completed
930 */
931 if (!(ccr & CCR_ENABLE)) {
932 ret = DMA_COMPLETE;
933 omap_dma_start_desc(c);
934 vchan_cookie_complete(&d->vd);
935 }
936 }
937
938 spin_unlock_irqrestore(&c->vc.lock, flags);
939
940 return ret;
941 }
942
943 static void omap_dma_issue_pending(struct dma_chan *chan)
944 {
945 struct omap_chan *c = to_omap_dma_chan(chan);
946 unsigned long flags;
947
948 spin_lock_irqsave(&c->vc.lock, flags);
949 if (vchan_issue_pending(&c->vc) && !c->desc)
950 omap_dma_start_desc(c);
951 spin_unlock_irqrestore(&c->vc.lock, flags);
952 }
953
954 static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
955 struct dma_chan *chan, struct scatterlist *sgl, unsigned sglen,
956 enum dma_transfer_direction dir, unsigned long tx_flags, void *context)
957 {
958 struct omap_dmadev *od = to_omap_dma_dev(chan->device);
959 struct omap_chan *c = to_omap_dma_chan(chan);
960 enum dma_slave_buswidth dev_width;
961 struct scatterlist *sgent;
962 struct omap_desc *d;
963 dma_addr_t dev_addr;
964 unsigned i, es, en, frame_bytes;
965 bool ll_failed = false;
966 u32 burst;
967 u32 port_window, port_window_bytes;
968
969 if (dir == DMA_DEV_TO_MEM) {
970 dev_addr = c->cfg.src_addr;
971 dev_width = c->cfg.src_addr_width;
972 burst = c->cfg.src_maxburst;
973 port_window = c->cfg.src_port_window_size;
974 } else if (dir == DMA_MEM_TO_DEV) {
975 dev_addr = c->cfg.dst_addr;
976 dev_width = c->cfg.dst_addr_width;
977 burst = c->cfg.dst_maxburst;
978 port_window = c->cfg.dst_port_window_size;
979 } else {
980 dev_err(chan->device->dev, "%s: bad direction?\n", __func__);
981 return NULL;
982 }
983
984 /* Bus width translates to the element size (ES) */
985 switch (dev_width) {
986 case DMA_SLAVE_BUSWIDTH_1_BYTE:
987 es = CSDP_DATA_TYPE_8;
988 break;
989 case DMA_SLAVE_BUSWIDTH_2_BYTES:
990 es = CSDP_DATA_TYPE_16;
991 break;
992 case DMA_SLAVE_BUSWIDTH_4_BYTES:
993 es = CSDP_DATA_TYPE_32;
994 break;
995 default: /* not reached */
996 return NULL;
997 }
998
999 /* Now allocate and setup the descriptor. */
1000 d = kzalloc(struct_size(d, sg, sglen), GFP_ATOMIC);
1001 if (!d)
1002 return NULL;
1003
1004 d->dir = dir;
1005 d->dev_addr = dev_addr;
1006 d->es = es;
1007
1008 /* When the port_window is used, one frame must cover the window */
1009 if (port_window) {
1010 burst = port_window;
1011 port_window_bytes = port_window * es_bytes[es];
1012
1013 d->ei = 1;
1014 /*
1015 * One frame covers the port_window and by configure
1016 * the source frame index to be -1 * (port_window - 1)
1017 * we instruct the sDMA that after a frame is processed
1018 * it should move back to the start of the window.
1019 */
1020 d->fi = -(port_window_bytes - 1);
1021 }
1022
1023 d->ccr = c->ccr | CCR_SYNC_FRAME;
1024 if (dir == DMA_DEV_TO_MEM) {
1025 d->csdp = CSDP_DST_BURST_64 | CSDP_DST_PACKED;
1026
1027 d->ccr |= CCR_DST_AMODE_POSTINC;
1028 if (port_window) {
1029 d->ccr |= CCR_SRC_AMODE_DBLIDX;
1030
1031 if (port_window_bytes >= 64)
1032 d->csdp |= CSDP_SRC_BURST_64;
1033 else if (port_window_bytes >= 32)
1034 d->csdp |= CSDP_SRC_BURST_32;
1035 else if (port_window_bytes >= 16)
1036 d->csdp |= CSDP_SRC_BURST_16;
1037
1038 } else {
1039 d->ccr |= CCR_SRC_AMODE_CONSTANT;
1040 }
1041 } else {
1042 d->csdp = CSDP_SRC_BURST_64 | CSDP_SRC_PACKED;
1043
1044 d->ccr |= CCR_SRC_AMODE_POSTINC;
1045 if (port_window) {
1046 d->ccr |= CCR_DST_AMODE_DBLIDX;
1047
1048 if (port_window_bytes >= 64)
1049 d->csdp |= CSDP_DST_BURST_64;
1050 else if (port_window_bytes >= 32)
1051 d->csdp |= CSDP_DST_BURST_32;
1052 else if (port_window_bytes >= 16)
1053 d->csdp |= CSDP_DST_BURST_16;
1054 } else {
1055 d->ccr |= CCR_DST_AMODE_CONSTANT;
1056 }
1057 }
1058
1059 d->cicr = CICR_DROP_IE | CICR_BLOCK_IE;
1060 d->csdp |= es;
1061
1062 if (dma_omap1()) {
1063 d->cicr |= CICR_TOUT_IE;
1064
1065 if (dir == DMA_DEV_TO_MEM)
1066 d->csdp |= CSDP_DST_PORT_EMIFF | CSDP_SRC_PORT_TIPB;
1067 else
1068 d->csdp |= CSDP_DST_PORT_TIPB | CSDP_SRC_PORT_EMIFF;
1069 } else {
1070 if (dir == DMA_DEV_TO_MEM)
1071 d->ccr |= CCR_TRIGGER_SRC;
1072
1073 d->cicr |= CICR_MISALIGNED_ERR_IE | CICR_TRANS_ERR_IE;
1074
1075 if (port_window)
1076 d->csdp |= CSDP_WRITE_LAST_NON_POSTED;
1077 }
1078 if (od->plat->errata & DMA_ERRATA_PARALLEL_CHANNELS)
1079 d->clnk_ctrl = c->dma_ch;
1080
1081 /*
1082 * Build our scatterlist entries: each contains the address,
1083 * the number of elements (EN) in each frame, and the number of
1084 * frames (FN). Number of bytes for this entry = ES * EN * FN.
1085 *
1086 * Burst size translates to number of elements with frame sync.
1087 * Note: DMA engine defines burst to be the number of dev-width
1088 * transfers.
1089 */
1090 en = burst;
1091 frame_bytes = es_bytes[es] * en;
1092
1093 if (sglen >= 2)
1094 d->using_ll = od->ll123_supported;
1095
1096 for_each_sg(sgl, sgent, sglen, i) {
1097 struct omap_sg *osg = &d->sg[i];
1098
1099 osg->addr = sg_dma_address(sgent);
1100 osg->en = en;
1101 osg->fn = sg_dma_len(sgent) / frame_bytes;
1102
1103 if (d->using_ll) {
1104 osg->t2_desc = dma_pool_alloc(od->desc_pool, GFP_ATOMIC,
1105 &osg->t2_desc_paddr);
1106 if (!osg->t2_desc) {
1107 dev_err(chan->device->dev,
1108 "t2_desc[%d] allocation failed\n", i);
1109 ll_failed = true;
1110 d->using_ll = false;
1111 continue;
1112 }
1113
1114 omap_dma_fill_type2_desc(d, i, dir, (i == sglen - 1));
1115 }
1116 }
1117
1118 d->sglen = sglen;
1119
1120 /* Release the dma_pool entries if one allocation failed */
1121 if (ll_failed) {
1122 for (i = 0; i < d->sglen; i++) {
1123 struct omap_sg *osg = &d->sg[i];
1124
1125 if (osg->t2_desc) {
1126 dma_pool_free(od->desc_pool, osg->t2_desc,
1127 osg->t2_desc_paddr);
1128 osg->t2_desc = NULL;
1129 }
1130 }
1131 }
1132
1133 return vchan_tx_prep(&c->vc, &d->vd, tx_flags);
1134 }
1135
1136 static struct dma_async_tx_descriptor *omap_dma_prep_dma_cyclic(
1137 struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
1138 size_t period_len, enum dma_transfer_direction dir, unsigned long flags)
1139 {
1140 struct omap_dmadev *od = to_omap_dma_dev(chan->device);
1141 struct omap_chan *c = to_omap_dma_chan(chan);
1142 enum dma_slave_buswidth dev_width;
1143 struct omap_desc *d;
1144 dma_addr_t dev_addr;
1145 unsigned es;
1146 u32 burst;
1147
1148 if (dir == DMA_DEV_TO_MEM) {
1149 dev_addr = c->cfg.src_addr;
1150 dev_width = c->cfg.src_addr_width;
1151 burst = c->cfg.src_maxburst;
1152 } else if (dir == DMA_MEM_TO_DEV) {
1153 dev_addr = c->cfg.dst_addr;
1154 dev_width = c->cfg.dst_addr_width;
1155 burst = c->cfg.dst_maxburst;
1156 } else {
1157 dev_err(chan->device->dev, "%s: bad direction?\n", __func__);
1158 return NULL;
1159 }
1160
1161 /* Bus width translates to the element size (ES) */
1162 switch (dev_width) {
1163 case DMA_SLAVE_BUSWIDTH_1_BYTE:
1164 es = CSDP_DATA_TYPE_8;
1165 break;
1166 case DMA_SLAVE_BUSWIDTH_2_BYTES:
1167 es = CSDP_DATA_TYPE_16;
1168 break;
1169 case DMA_SLAVE_BUSWIDTH_4_BYTES:
1170 es = CSDP_DATA_TYPE_32;
1171 break;
1172 default: /* not reached */
1173 return NULL;
1174 }
1175
1176 /* Now allocate and setup the descriptor. */
1177 d = kzalloc(sizeof(*d) + sizeof(d->sg[0]), GFP_ATOMIC);
1178 if (!d)
1179 return NULL;
1180
1181 d->dir = dir;
1182 d->dev_addr = dev_addr;
1183 d->fi = burst;
1184 d->es = es;
1185 d->sg[0].addr = buf_addr;
1186 d->sg[0].en = period_len / es_bytes[es];
1187 d->sg[0].fn = buf_len / period_len;
1188 d->sglen = 1;
1189
1190 d->ccr = c->ccr;
1191 if (dir == DMA_DEV_TO_MEM)
1192 d->ccr |= CCR_DST_AMODE_POSTINC | CCR_SRC_AMODE_CONSTANT;
1193 else
1194 d->ccr |= CCR_DST_AMODE_CONSTANT | CCR_SRC_AMODE_POSTINC;
1195
1196 d->cicr = CICR_DROP_IE;
1197 if (flags & DMA_PREP_INTERRUPT)
1198 d->cicr |= CICR_FRAME_IE;
1199
1200 d->csdp = es;
1201
1202 if (dma_omap1()) {
1203 d->cicr |= CICR_TOUT_IE;
1204
1205 if (dir == DMA_DEV_TO_MEM)
1206 d->csdp |= CSDP_DST_PORT_EMIFF | CSDP_SRC_PORT_MPUI;
1207 else
1208 d->csdp |= CSDP_DST_PORT_MPUI | CSDP_SRC_PORT_EMIFF;
1209 } else {
1210 if (burst)
1211 d->ccr |= CCR_SYNC_PACKET;
1212 else
1213 d->ccr |= CCR_SYNC_ELEMENT;
1214
1215 if (dir == DMA_DEV_TO_MEM) {
1216 d->ccr |= CCR_TRIGGER_SRC;
1217 d->csdp |= CSDP_DST_PACKED;
1218 } else {
1219 d->csdp |= CSDP_SRC_PACKED;
1220 }
1221
1222 d->cicr |= CICR_MISALIGNED_ERR_IE | CICR_TRANS_ERR_IE;
1223
1224 d->csdp |= CSDP_DST_BURST_64 | CSDP_SRC_BURST_64;
1225 }
1226
1227 if (__dma_omap15xx(od->plat->dma_attr))
1228 d->ccr |= CCR_AUTO_INIT | CCR_REPEAT;
1229 else
1230 d->clnk_ctrl = c->dma_ch | CLNK_CTRL_ENABLE_LNK;
1231
1232 c->cyclic = true;
1233
1234 return vchan_tx_prep(&c->vc, &d->vd, flags);
1235 }
1236
1237 static struct dma_async_tx_descriptor *omap_dma_prep_dma_memcpy(
1238 struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1239 size_t len, unsigned long tx_flags)
1240 {
1241 struct omap_chan *c = to_omap_dma_chan(chan);
1242 struct omap_desc *d;
1243 uint8_t data_type;
1244
1245 d = kzalloc(sizeof(*d) + sizeof(d->sg[0]), GFP_ATOMIC);
1246 if (!d)
1247 return NULL;
1248
1249 data_type = __ffs((src | dest | len));
1250 if (data_type > CSDP_DATA_TYPE_32)
1251 data_type = CSDP_DATA_TYPE_32;
1252
1253 d->dir = DMA_MEM_TO_MEM;
1254 d->dev_addr = src;
1255 d->fi = 0;
1256 d->es = data_type;
1257 d->sg[0].en = len / BIT(data_type);
1258 d->sg[0].fn = 1;
1259 d->sg[0].addr = dest;
1260 d->sglen = 1;
1261 d->ccr = c->ccr;
1262 d->ccr |= CCR_DST_AMODE_POSTINC | CCR_SRC_AMODE_POSTINC;
1263
1264 if (tx_flags & DMA_PREP_INTERRUPT)
1265 d->cicr |= CICR_FRAME_IE;
1266 else
1267 d->polled = true;
1268
1269 d->csdp = data_type;
1270
1271 if (dma_omap1()) {
1272 d->cicr |= CICR_TOUT_IE;
1273 d->csdp |= CSDP_DST_PORT_EMIFF | CSDP_SRC_PORT_EMIFF;
1274 } else {
1275 d->csdp |= CSDP_DST_PACKED | CSDP_SRC_PACKED;
1276 d->cicr |= CICR_MISALIGNED_ERR_IE | CICR_TRANS_ERR_IE;
1277 d->csdp |= CSDP_DST_BURST_64 | CSDP_SRC_BURST_64;
1278 }
1279
1280 return vchan_tx_prep(&c->vc, &d->vd, tx_flags);
1281 }
1282
1283 static struct dma_async_tx_descriptor *omap_dma_prep_dma_interleaved(
1284 struct dma_chan *chan, struct dma_interleaved_template *xt,
1285 unsigned long flags)
1286 {
1287 struct omap_chan *c = to_omap_dma_chan(chan);
1288 struct omap_desc *d;
1289 struct omap_sg *sg;
1290 uint8_t data_type;
1291 size_t src_icg, dst_icg;
1292
1293 /* Slave mode is not supported */
1294 if (is_slave_direction(xt->dir))
1295 return NULL;
1296
1297 if (xt->frame_size != 1 || xt->numf == 0)
1298 return NULL;
1299
1300 d = kzalloc(sizeof(*d) + sizeof(d->sg[0]), GFP_ATOMIC);
1301 if (!d)
1302 return NULL;
1303
1304 data_type = __ffs((xt->src_start | xt->dst_start | xt->sgl[0].size));
1305 if (data_type > CSDP_DATA_TYPE_32)
1306 data_type = CSDP_DATA_TYPE_32;
1307
1308 sg = &d->sg[0];
1309 d->dir = DMA_MEM_TO_MEM;
1310 d->dev_addr = xt->src_start;
1311 d->es = data_type;
1312 sg->en = xt->sgl[0].size / BIT(data_type);
1313 sg->fn = xt->numf;
1314 sg->addr = xt->dst_start;
1315 d->sglen = 1;
1316 d->ccr = c->ccr;
1317
1318 src_icg = dmaengine_get_src_icg(xt, &xt->sgl[0]);
1319 dst_icg = dmaengine_get_dst_icg(xt, &xt->sgl[0]);
1320 if (src_icg) {
1321 d->ccr |= CCR_SRC_AMODE_DBLIDX;
1322 d->ei = 1;
1323 d->fi = src_icg + 1;
1324 } else if (xt->src_inc) {
1325 d->ccr |= CCR_SRC_AMODE_POSTINC;
1326 d->fi = 0;
1327 } else {
1328 dev_err(chan->device->dev,
1329 "%s: SRC constant addressing is not supported\n",
1330 __func__);
1331 kfree(d);
1332 return NULL;
1333 }
1334
1335 if (dst_icg) {
1336 d->ccr |= CCR_DST_AMODE_DBLIDX;
1337 sg->ei = 1;
1338 sg->fi = dst_icg + 1;
1339 } else if (xt->dst_inc) {
1340 d->ccr |= CCR_DST_AMODE_POSTINC;
1341 sg->fi = 0;
1342 } else {
1343 dev_err(chan->device->dev,
1344 "%s: DST constant addressing is not supported\n",
1345 __func__);
1346 kfree(d);
1347 return NULL;
1348 }
1349
1350 d->cicr = CICR_DROP_IE | CICR_FRAME_IE;
1351
1352 d->csdp = data_type;
1353
1354 if (dma_omap1()) {
1355 d->cicr |= CICR_TOUT_IE;
1356 d->csdp |= CSDP_DST_PORT_EMIFF | CSDP_SRC_PORT_EMIFF;
1357 } else {
1358 d->csdp |= CSDP_DST_PACKED | CSDP_SRC_PACKED;
1359 d->cicr |= CICR_MISALIGNED_ERR_IE | CICR_TRANS_ERR_IE;
1360 d->csdp |= CSDP_DST_BURST_64 | CSDP_SRC_BURST_64;
1361 }
1362
1363 return vchan_tx_prep(&c->vc, &d->vd, flags);
1364 }
1365
1366 static int omap_dma_slave_config(struct dma_chan *chan, struct dma_slave_config *cfg)
1367 {
1368 struct omap_chan *c = to_omap_dma_chan(chan);
1369
1370 if (cfg->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
1371 cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
1372 return -EINVAL;
1373
1374 if (cfg->src_maxburst > chan->device->max_burst ||
1375 cfg->dst_maxburst > chan->device->max_burst)
1376 return -EINVAL;
1377
1378 memcpy(&c->cfg, cfg, sizeof(c->cfg));
1379
1380 return 0;
1381 }
1382
1383 static int omap_dma_terminate_all(struct dma_chan *chan)
1384 {
1385 struct omap_chan *c = to_omap_dma_chan(chan);
1386 unsigned long flags;
1387 LIST_HEAD(head);
1388
1389 spin_lock_irqsave(&c->vc.lock, flags);
1390
1391 /*
1392 * Stop DMA activity: we assume the callback will not be called
1393 * after omap_dma_stop() returns (even if it does, it will see
1394 * c->desc is NULL and exit.)
1395 */
1396 if (c->desc) {
1397 vchan_terminate_vdesc(&c->desc->vd);
1398 c->desc = NULL;
1399 /* Avoid stopping the dma twice */
1400 if (!c->paused)
1401 omap_dma_stop(c);
1402 }
1403
1404 c->cyclic = false;
1405 c->paused = false;
1406
1407 vchan_get_all_descriptors(&c->vc, &head);
1408 spin_unlock_irqrestore(&c->vc.lock, flags);
1409 vchan_dma_desc_free_list(&c->vc, &head);
1410
1411 return 0;
1412 }
1413
1414 static void omap_dma_synchronize(struct dma_chan *chan)
1415 {
1416 struct omap_chan *c = to_omap_dma_chan(chan);
1417
1418 vchan_synchronize(&c->vc);
1419 }
1420
1421 static int omap_dma_pause(struct dma_chan *chan)
1422 {
1423 struct omap_chan *c = to_omap_dma_chan(chan);
1424 struct omap_dmadev *od = to_omap_dma_dev(chan->device);
1425 unsigned long flags;
1426 int ret = -EINVAL;
1427 bool can_pause = false;
1428
1429 spin_lock_irqsave(&od->irq_lock, flags);
1430
1431 if (!c->desc)
1432 goto out;
1433
1434 if (c->cyclic)
1435 can_pause = true;
1436
1437 /*
1438 * We do not allow DMA_MEM_TO_DEV transfers to be paused.
1439 * From the AM572x TRM, 16.1.4.18 Disabling a Channel During Transfer:
1440 * "When a channel is disabled during a transfer, the channel undergoes
1441 * an abort, unless it is hardware-source-synchronized …".
1442 * A source-synchronised channel is one where the fetching of data is
1443 * under control of the device. In other words, a device-to-memory
1444 * transfer. So, a destination-synchronised channel (which would be a
1445 * memory-to-device transfer) undergoes an abort if the the CCR_ENABLE
1446 * bit is cleared.
1447 * From 16.1.4.20.4.6.2 Abort: "If an abort trigger occurs, the channel
1448 * aborts immediately after completion of current read/write
1449 * transactions and then the FIFO is cleaned up." The term "cleaned up"
1450 * is not defined. TI recommends to check that RD_ACTIVE and WR_ACTIVE
1451 * are both clear _before_ disabling the channel, otherwise data loss
1452 * will occur.
1453 * The problem is that if the channel is active, then device activity
1454 * can result in DMA activity starting between reading those as both
1455 * clear and the write to DMA_CCR to clear the enable bit hitting the
1456 * hardware. If the DMA hardware can't drain the data in its FIFO to the
1457 * destination, then data loss "might" occur (say if we write to an UART
1458 * and the UART is not accepting any further data).
1459 */
1460 else if (c->desc->dir == DMA_DEV_TO_MEM)
1461 can_pause = true;
1462
1463 if (can_pause && !c->paused) {
1464 ret = omap_dma_stop(c);
1465 if (!ret)
1466 c->paused = true;
1467 }
1468 out:
1469 spin_unlock_irqrestore(&od->irq_lock, flags);
1470
1471 return ret;
1472 }
1473
1474 static int omap_dma_resume(struct dma_chan *chan)
1475 {
1476 struct omap_chan *c = to_omap_dma_chan(chan);
1477 struct omap_dmadev *od = to_omap_dma_dev(chan->device);
1478 unsigned long flags;
1479 int ret = -EINVAL;
1480
1481 spin_lock_irqsave(&od->irq_lock, flags);
1482
1483 if (c->paused && c->desc) {
1484 mb();
1485
1486 /* Restore channel link register */
1487 omap_dma_chan_write(c, CLNK_CTRL, c->desc->clnk_ctrl);
1488
1489 omap_dma_start(c, c->desc);
1490 c->paused = false;
1491 ret = 0;
1492 }
1493 spin_unlock_irqrestore(&od->irq_lock, flags);
1494
1495 return ret;
1496 }
1497
1498 static int omap_dma_chan_init(struct omap_dmadev *od)
1499 {
1500 struct omap_chan *c;
1501
1502 c = kzalloc(sizeof(*c), GFP_KERNEL);
1503 if (!c)
1504 return -ENOMEM;
1505
1506 c->reg_map = od->reg_map;
1507 c->vc.desc_free = omap_dma_desc_free;
1508 vchan_init(&c->vc, &od->ddev);
1509
1510 return 0;
1511 }
1512
1513 static void omap_dma_free(struct omap_dmadev *od)
1514 {
1515 while (!list_empty(&od->ddev.channels)) {
1516 struct omap_chan *c = list_first_entry(&od->ddev.channels,
1517 struct omap_chan, vc.chan.device_node);
1518
1519 list_del(&c->vc.chan.device_node);
1520 tasklet_kill(&c->vc.task);
1521 kfree(c);
1522 }
1523 }
1524
1525 /* Currently only used for omap2. For omap1, also a check for lcd_dma is needed */
1526 static int omap_dma_busy_notifier(struct notifier_block *nb,
1527 unsigned long cmd, void *v)
1528 {
1529 struct omap_dmadev *od;
1530 struct omap_chan *c;
1531 int lch = -1;
1532
1533 od = container_of(nb, struct omap_dmadev, nb);
1534
1535 switch (cmd) {
1536 case CPU_CLUSTER_PM_ENTER:
1537 while (1) {
1538 lch = find_next_bit(od->lch_bitmap, od->lch_count,
1539 lch + 1);
1540 if (lch >= od->lch_count)
1541 break;
1542 c = od->lch_map[lch];
1543 if (!c)
1544 continue;
1545 if (omap_dma_chan_read(c, CCR) & CCR_ENABLE)
1546 return NOTIFY_BAD;
1547 }
1548 break;
1549 case CPU_CLUSTER_PM_ENTER_FAILED:
1550 case CPU_CLUSTER_PM_EXIT:
1551 break;
1552 }
1553
1554 return NOTIFY_OK;
1555 }
1556
1557 /*
1558 * We are using IRQENABLE_L1, and legacy DMA code was using IRQENABLE_L0.
1559 * As the DSP may be using IRQENABLE_L2 and L3, let's not touch those for
1560 * now. Context save seems to be only currently needed on omap3.
1561 */
1562 static void omap_dma_context_save(struct omap_dmadev *od)
1563 {
1564 od->context.irqenable_l0 = omap_dma_glbl_read(od, IRQENABLE_L0);
1565 od->context.irqenable_l1 = omap_dma_glbl_read(od, IRQENABLE_L1);
1566 od->context.ocp_sysconfig = omap_dma_glbl_read(od, OCP_SYSCONFIG);
1567 od->context.gcr = omap_dma_glbl_read(od, GCR);
1568 }
1569
1570 static void omap_dma_context_restore(struct omap_dmadev *od)
1571 {
1572 int i;
1573
1574 omap_dma_glbl_write(od, GCR, od->context.gcr);
1575 omap_dma_glbl_write(od, OCP_SYSCONFIG, od->context.ocp_sysconfig);
1576 omap_dma_glbl_write(od, IRQENABLE_L0, od->context.irqenable_l0);
1577 omap_dma_glbl_write(od, IRQENABLE_L1, od->context.irqenable_l1);
1578
1579 /* Clear IRQSTATUS_L0 as legacy DMA code is no longer doing it */
1580 if (od->plat->errata & DMA_ROMCODE_BUG)
1581 omap_dma_glbl_write(od, IRQSTATUS_L0, 0);
1582
1583 /* Clear dma channels */
1584 for (i = 0; i < od->lch_count; i++)
1585 omap_dma_clear_lch(od, i);
1586 }
1587
1588 /* Currently only used for omap3 */
1589 static int omap_dma_context_notifier(struct notifier_block *nb,
1590 unsigned long cmd, void *v)
1591 {
1592 struct omap_dmadev *od;
1593
1594 od = container_of(nb, struct omap_dmadev, nb);
1595
1596 switch (cmd) {
1597 case CPU_CLUSTER_PM_ENTER:
1598 omap_dma_context_save(od);
1599 break;
1600 case CPU_CLUSTER_PM_ENTER_FAILED:
1601 case CPU_CLUSTER_PM_EXIT:
1602 omap_dma_context_restore(od);
1603 break;
1604 }
1605
1606 return NOTIFY_OK;
1607 }
1608
1609 static void omap_dma_init_gcr(struct omap_dmadev *od, int arb_rate,
1610 int max_fifo_depth, int tparams)
1611 {
1612 u32 val;
1613
1614 /* Set only for omap2430 and later */
1615 if (!od->cfg->rw_priority)
1616 return;
1617
1618 if (max_fifo_depth == 0)
1619 max_fifo_depth = 1;
1620 if (arb_rate == 0)
1621 arb_rate = 1;
1622
1623 val = 0xff & max_fifo_depth;
1624 val |= (0x3 & tparams) << 12;
1625 val |= (arb_rate & 0xff) << 16;
1626
1627 omap_dma_glbl_write(od, GCR, val);
1628 }
1629
1630 #define OMAP_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
1631 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
1632 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
1633
1634 /*
1635 * No flags currently set for default configuration as omap1 is still
1636 * using platform data.
1637 */
1638 static const struct omap_dma_config default_cfg;
1639
1640 static int omap_dma_probe(struct platform_device *pdev)
1641 {
1642 const struct omap_dma_config *conf;
1643 struct omap_dmadev *od;
1644 struct resource *res;
1645 int rc, i, irq;
1646 u32 val;
1647
1648 od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
1649 if (!od)
1650 return -ENOMEM;
1651
1652 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1653 od->base = devm_ioremap_resource(&pdev->dev, res);
1654 if (IS_ERR(od->base))
1655 return PTR_ERR(od->base);
1656
1657 conf = of_device_get_match_data(&pdev->dev);
1658 if (conf) {
1659 od->cfg = conf;
1660 od->plat = dev_get_platdata(&pdev->dev);
1661 if (!od->plat) {
1662 dev_err(&pdev->dev, "omap_system_dma_plat_info is missing");
1663 return -ENODEV;
1664 }
1665 } else {
1666 od->cfg = &default_cfg;
1667
1668 od->plat = omap_get_plat_info();
1669 if (!od->plat)
1670 return -EPROBE_DEFER;
1671 }
1672
1673 od->reg_map = od->plat->reg_map;
1674
1675 dma_cap_set(DMA_SLAVE, od->ddev.cap_mask);
1676 dma_cap_set(DMA_CYCLIC, od->ddev.cap_mask);
1677 dma_cap_set(DMA_MEMCPY, od->ddev.cap_mask);
1678 dma_cap_set(DMA_INTERLEAVE, od->ddev.cap_mask);
1679 od->ddev.device_alloc_chan_resources = omap_dma_alloc_chan_resources;
1680 od->ddev.device_free_chan_resources = omap_dma_free_chan_resources;
1681 od->ddev.device_tx_status = omap_dma_tx_status;
1682 od->ddev.device_issue_pending = omap_dma_issue_pending;
1683 od->ddev.device_prep_slave_sg = omap_dma_prep_slave_sg;
1684 od->ddev.device_prep_dma_cyclic = omap_dma_prep_dma_cyclic;
1685 od->ddev.device_prep_dma_memcpy = omap_dma_prep_dma_memcpy;
1686 od->ddev.device_prep_interleaved_dma = omap_dma_prep_dma_interleaved;
1687 od->ddev.device_config = omap_dma_slave_config;
1688 od->ddev.device_pause = omap_dma_pause;
1689 od->ddev.device_resume = omap_dma_resume;
1690 od->ddev.device_terminate_all = omap_dma_terminate_all;
1691 od->ddev.device_synchronize = omap_dma_synchronize;
1692 od->ddev.src_addr_widths = OMAP_DMA_BUSWIDTHS;
1693 od->ddev.dst_addr_widths = OMAP_DMA_BUSWIDTHS;
1694 od->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1695 if (__dma_omap15xx(od->plat->dma_attr))
1696 od->ddev.residue_granularity =
1697 DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1698 else
1699 od->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1700 od->ddev.max_burst = SZ_16M - 1; /* CCEN: 24bit unsigned */
1701 od->ddev.dev = &pdev->dev;
1702 INIT_LIST_HEAD(&od->ddev.channels);
1703 mutex_init(&od->lch_lock);
1704 spin_lock_init(&od->lock);
1705 spin_lock_init(&od->irq_lock);
1706
1707 /* Number of DMA requests */
1708 od->dma_requests = OMAP_SDMA_REQUESTS;
1709 if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,
1710 "dma-requests",
1711 &od->dma_requests)) {
1712 dev_info(&pdev->dev,
1713 "Missing dma-requests property, using %u.\n",
1714 OMAP_SDMA_REQUESTS);
1715 }
1716
1717 /* Number of available logical channels */
1718 if (!pdev->dev.of_node) {
1719 od->lch_count = od->plat->dma_attr->lch_count;
1720 if (unlikely(!od->lch_count))
1721 od->lch_count = OMAP_SDMA_CHANNELS;
1722 } else if (of_property_read_u32(pdev->dev.of_node, "dma-channels",
1723 &od->lch_count)) {
1724 dev_info(&pdev->dev,
1725 "Missing dma-channels property, using %u.\n",
1726 OMAP_SDMA_CHANNELS);
1727 od->lch_count = OMAP_SDMA_CHANNELS;
1728 }
1729
1730 /* Mask of allowed logical channels */
1731 if (pdev->dev.of_node && !of_property_read_u32(pdev->dev.of_node,
1732 "dma-channel-mask",
1733 &val)) {
1734 /* Tag channels not in mask as reserved */
1735 val = ~val;
1736 bitmap_from_arr32(od->lch_bitmap, &val, od->lch_count);
1737 }
1738 if (od->plat->dma_attr->dev_caps & HS_CHANNELS_RESERVED)
1739 bitmap_set(od->lch_bitmap, 0, 2);
1740
1741 od->lch_map = devm_kcalloc(&pdev->dev, od->lch_count,
1742 sizeof(*od->lch_map),
1743 GFP_KERNEL);
1744 if (!od->lch_map)
1745 return -ENOMEM;
1746
1747 for (i = 0; i < od->dma_requests; i++) {
1748 rc = omap_dma_chan_init(od);
1749 if (rc) {
1750 omap_dma_free(od);
1751 return rc;
1752 }
1753 }
1754
1755 irq = platform_get_irq(pdev, 1);
1756 if (irq <= 0) {
1757 dev_info(&pdev->dev, "failed to get L1 IRQ: %d\n", irq);
1758 od->legacy = true;
1759 } else {
1760 /* Disable all interrupts */
1761 od->irq_enable_mask = 0;
1762 omap_dma_glbl_write(od, IRQENABLE_L1, 0);
1763
1764 rc = devm_request_irq(&pdev->dev, irq, omap_dma_irq,
1765 IRQF_SHARED, "omap-dma-engine", od);
1766 if (rc) {
1767 omap_dma_free(od);
1768 return rc;
1769 }
1770 }
1771
1772 if (omap_dma_glbl_read(od, CAPS_0) & CAPS_0_SUPPORT_LL123)
1773 od->ll123_supported = true;
1774
1775 od->ddev.filter.map = od->plat->slave_map;
1776 od->ddev.filter.mapcnt = od->plat->slavecnt;
1777 od->ddev.filter.fn = omap_dma_filter_fn;
1778
1779 if (od->ll123_supported) {
1780 od->desc_pool = dma_pool_create(dev_name(&pdev->dev),
1781 &pdev->dev,
1782 sizeof(struct omap_type2_desc),
1783 4, 0);
1784 if (!od->desc_pool) {
1785 dev_err(&pdev->dev,
1786 "unable to allocate descriptor pool\n");
1787 od->ll123_supported = false;
1788 }
1789 }
1790
1791 rc = dma_async_device_register(&od->ddev);
1792 if (rc) {
1793 pr_warn("OMAP-DMA: failed to register slave DMA engine device: %d\n",
1794 rc);
1795 omap_dma_free(od);
1796 return rc;
1797 }
1798
1799 platform_set_drvdata(pdev, od);
1800
1801 if (pdev->dev.of_node) {
1802 omap_dma_info.dma_cap = od->ddev.cap_mask;
1803
1804 /* Device-tree DMA controller registration */
1805 rc = of_dma_controller_register(pdev->dev.of_node,
1806 of_dma_simple_xlate, &omap_dma_info);
1807 if (rc) {
1808 pr_warn("OMAP-DMA: failed to register DMA controller\n");
1809 dma_async_device_unregister(&od->ddev);
1810 omap_dma_free(od);
1811 }
1812 }
1813
1814 omap_dma_init_gcr(od, DMA_DEFAULT_ARB_RATE, DMA_DEFAULT_FIFO_DEPTH, 0);
1815
1816 if (od->cfg->needs_busy_check) {
1817 od->nb.notifier_call = omap_dma_busy_notifier;
1818 cpu_pm_register_notifier(&od->nb);
1819 } else if (od->cfg->may_lose_context) {
1820 od->nb.notifier_call = omap_dma_context_notifier;
1821 cpu_pm_register_notifier(&od->nb);
1822 }
1823
1824 dev_info(&pdev->dev, "OMAP DMA engine driver%s\n",
1825 od->ll123_supported ? " (LinkedList1/2/3 supported)" : "");
1826
1827 return rc;
1828 }
1829
1830 static int omap_dma_remove(struct platform_device *pdev)
1831 {
1832 struct omap_dmadev *od = platform_get_drvdata(pdev);
1833 int irq;
1834
1835 if (od->cfg->may_lose_context)
1836 cpu_pm_unregister_notifier(&od->nb);
1837
1838 if (pdev->dev.of_node)
1839 of_dma_controller_free(pdev->dev.of_node);
1840
1841 irq = platform_get_irq(pdev, 1);
1842 devm_free_irq(&pdev->dev, irq, od);
1843
1844 dma_async_device_unregister(&od->ddev);
1845
1846 if (!od->legacy) {
1847 /* Disable all interrupts */
1848 omap_dma_glbl_write(od, IRQENABLE_L0, 0);
1849 }
1850
1851 if (od->ll123_supported)
1852 dma_pool_destroy(od->desc_pool);
1853
1854 omap_dma_free(od);
1855
1856 return 0;
1857 }
1858
1859 static const struct omap_dma_config omap2420_data = {
1860 .lch_end = CCFN,
1861 .rw_priority = true,
1862 .needs_lch_clear = true,
1863 .needs_busy_check = true,
1864 };
1865
1866 static const struct omap_dma_config omap2430_data = {
1867 .lch_end = CCFN,
1868 .rw_priority = true,
1869 .needs_lch_clear = true,
1870 };
1871
1872 static const struct omap_dma_config omap3430_data = {
1873 .lch_end = CCFN,
1874 .rw_priority = true,
1875 .needs_lch_clear = true,
1876 .may_lose_context = true,
1877 };
1878
1879 static const struct omap_dma_config omap3630_data = {
1880 .lch_end = CCDN,
1881 .rw_priority = true,
1882 .needs_lch_clear = true,
1883 .may_lose_context = true,
1884 };
1885
1886 static const struct omap_dma_config omap4_data = {
1887 .lch_end = CCDN,
1888 .rw_priority = true,
1889 .needs_lch_clear = true,
1890 };
1891
1892 static const struct of_device_id omap_dma_match[] = {
1893 { .compatible = "ti,omap2420-sdma", .data = &omap2420_data, },
1894 { .compatible = "ti,omap2430-sdma", .data = &omap2430_data, },
1895 { .compatible = "ti,omap3430-sdma", .data = &omap3430_data, },
1896 { .compatible = "ti,omap3630-sdma", .data = &omap3630_data, },
1897 { .compatible = "ti,omap4430-sdma", .data = &omap4_data, },
1898 {},
1899 };
1900 MODULE_DEVICE_TABLE(of, omap_dma_match);
1901
1902 static struct platform_driver omap_dma_driver = {
1903 .probe = omap_dma_probe,
1904 .remove = omap_dma_remove,
1905 .driver = {
1906 .name = "omap-dma-engine",
1907 .of_match_table = of_match_ptr(omap_dma_match),
1908 },
1909 };
1910
1911 static bool omap_dma_filter_fn(struct dma_chan *chan, void *param)
1912 {
1913 if (chan->device->dev->driver == &omap_dma_driver.driver) {
1914 struct omap_dmadev *od = to_omap_dma_dev(chan->device);
1915 struct omap_chan *c = to_omap_dma_chan(chan);
1916 unsigned req = *(unsigned *)param;
1917
1918 if (req <= od->dma_requests) {
1919 c->dma_sig = req;
1920 return true;
1921 }
1922 }
1923 return false;
1924 }
1925
1926 static int omap_dma_init(void)
1927 {
1928 return platform_driver_register(&omap_dma_driver);
1929 }
1930 subsys_initcall(omap_dma_init);
1931
1932 static void __exit omap_dma_exit(void)
1933 {
1934 platform_driver_unregister(&omap_dma_driver);
1935 }
1936 module_exit(omap_dma_exit);
1937
1938 MODULE_AUTHOR("Russell King");
1939 MODULE_LICENSE("GPL");
Linux with added FPC-III support