xref: /openbmc/linux/drivers/dma/ti/omap-dma.c (revision 0a94608f)
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 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 used by omap2 & 3 to block deeper SoC idle states */
1526 static bool omap_dma_busy(struct omap_dmadev *od)
1527 {
1528 	struct omap_chan *c;
1529 	int lch = -1;
1530 
1531 	while (1) {
1532 		lch = find_next_bit(od->lch_bitmap, od->lch_count, lch + 1);
1533 		if (lch >= od->lch_count)
1534 			break;
1535 		c = od->lch_map[lch];
1536 		if (!c)
1537 			continue;
1538 		if (omap_dma_chan_read(c, CCR) & CCR_ENABLE)
1539 			return true;
1540 	}
1541 
1542 	return false;
1543 }
1544 
1545 /* Currently only used for omap2. For omap1, also a check for lcd_dma is needed */
1546 static int omap_dma_busy_notifier(struct notifier_block *nb,
1547 				  unsigned long cmd, void *v)
1548 {
1549 	struct omap_dmadev *od;
1550 
1551 	od = container_of(nb, struct omap_dmadev, nb);
1552 
1553 	switch (cmd) {
1554 	case CPU_CLUSTER_PM_ENTER:
1555 		if (omap_dma_busy(od))
1556 			return NOTIFY_BAD;
1557 		break;
1558 	case CPU_CLUSTER_PM_ENTER_FAILED:
1559 	case CPU_CLUSTER_PM_EXIT:
1560 		break;
1561 	}
1562 
1563 	return NOTIFY_OK;
1564 }
1565 
1566 /*
1567  * We are using IRQENABLE_L1, and legacy DMA code was using IRQENABLE_L0.
1568  * As the DSP may be using IRQENABLE_L2 and L3, let's not touch those for
1569  * now. Context save seems to be only currently needed on omap3.
1570  */
1571 static void omap_dma_context_save(struct omap_dmadev *od)
1572 {
1573 	od->context.irqenable_l0 = omap_dma_glbl_read(od, IRQENABLE_L0);
1574 	od->context.irqenable_l1 = omap_dma_glbl_read(od, IRQENABLE_L1);
1575 	od->context.ocp_sysconfig = omap_dma_glbl_read(od, OCP_SYSCONFIG);
1576 	od->context.gcr = omap_dma_glbl_read(od, GCR);
1577 }
1578 
1579 static void omap_dma_context_restore(struct omap_dmadev *od)
1580 {
1581 	int i;
1582 
1583 	omap_dma_glbl_write(od, GCR, od->context.gcr);
1584 	omap_dma_glbl_write(od, OCP_SYSCONFIG, od->context.ocp_sysconfig);
1585 	omap_dma_glbl_write(od, IRQENABLE_L0, od->context.irqenable_l0);
1586 	omap_dma_glbl_write(od, IRQENABLE_L1, od->context.irqenable_l1);
1587 
1588 	/* Clear IRQSTATUS_L0 as legacy DMA code is no longer doing it */
1589 	if (od->plat->errata & DMA_ROMCODE_BUG)
1590 		omap_dma_glbl_write(od, IRQSTATUS_L0, 0);
1591 
1592 	/* Clear dma channels */
1593 	for (i = 0; i < od->lch_count; i++)
1594 		omap_dma_clear_lch(od, i);
1595 }
1596 
1597 /* Currently only used for omap3 */
1598 static int omap_dma_context_notifier(struct notifier_block *nb,
1599 				     unsigned long cmd, void *v)
1600 {
1601 	struct omap_dmadev *od;
1602 
1603 	od = container_of(nb, struct omap_dmadev, nb);
1604 
1605 	switch (cmd) {
1606 	case CPU_CLUSTER_PM_ENTER:
1607 		if (omap_dma_busy(od))
1608 			return NOTIFY_BAD;
1609 		omap_dma_context_save(od);
1610 		break;
1611 	case CPU_CLUSTER_PM_ENTER_FAILED:	/* No need to restore context */
1612 		break;
1613 	case CPU_CLUSTER_PM_EXIT:
1614 		omap_dma_context_restore(od);
1615 		break;
1616 	}
1617 
1618 	return NOTIFY_OK;
1619 }
1620 
1621 static void omap_dma_init_gcr(struct omap_dmadev *od, int arb_rate,
1622 			      int max_fifo_depth, int tparams)
1623 {
1624 	u32 val;
1625 
1626 	/* Set only for omap2430 and later */
1627 	if (!od->cfg->rw_priority)
1628 		return;
1629 
1630 	if (max_fifo_depth == 0)
1631 		max_fifo_depth = 1;
1632 	if (arb_rate == 0)
1633 		arb_rate = 1;
1634 
1635 	val = 0xff & max_fifo_depth;
1636 	val |= (0x3 & tparams) << 12;
1637 	val |= (arb_rate & 0xff) << 16;
1638 
1639 	omap_dma_glbl_write(od, GCR, val);
1640 }
1641 
1642 #define OMAP_DMA_BUSWIDTHS	(BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
1643 				 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
1644 				 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
1645 
1646 /*
1647  * No flags currently set for default configuration as omap1 is still
1648  * using platform data.
1649  */
1650 static const struct omap_dma_config default_cfg;
1651 
1652 static int omap_dma_probe(struct platform_device *pdev)
1653 {
1654 	const struct omap_dma_config *conf;
1655 	struct omap_dmadev *od;
1656 	struct resource *res;
1657 	int rc, i, irq;
1658 	u32 val;
1659 
1660 	od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
1661 	if (!od)
1662 		return -ENOMEM;
1663 
1664 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1665 	od->base = devm_ioremap_resource(&pdev->dev, res);
1666 	if (IS_ERR(od->base))
1667 		return PTR_ERR(od->base);
1668 
1669 	conf = of_device_get_match_data(&pdev->dev);
1670 	if (conf) {
1671 		od->cfg = conf;
1672 		od->plat = dev_get_platdata(&pdev->dev);
1673 		if (!od->plat) {
1674 			dev_err(&pdev->dev, "omap_system_dma_plat_info is missing");
1675 			return -ENODEV;
1676 		}
1677 	} else {
1678 		od->cfg = &default_cfg;
1679 
1680 		od->plat = omap_get_plat_info();
1681 		if (!od->plat)
1682 			return -EPROBE_DEFER;
1683 	}
1684 
1685 	od->reg_map = od->plat->reg_map;
1686 
1687 	dma_cap_set(DMA_SLAVE, od->ddev.cap_mask);
1688 	dma_cap_set(DMA_CYCLIC, od->ddev.cap_mask);
1689 	dma_cap_set(DMA_MEMCPY, od->ddev.cap_mask);
1690 	dma_cap_set(DMA_INTERLEAVE, od->ddev.cap_mask);
1691 	od->ddev.device_alloc_chan_resources = omap_dma_alloc_chan_resources;
1692 	od->ddev.device_free_chan_resources = omap_dma_free_chan_resources;
1693 	od->ddev.device_tx_status = omap_dma_tx_status;
1694 	od->ddev.device_issue_pending = omap_dma_issue_pending;
1695 	od->ddev.device_prep_slave_sg = omap_dma_prep_slave_sg;
1696 	od->ddev.device_prep_dma_cyclic = omap_dma_prep_dma_cyclic;
1697 	od->ddev.device_prep_dma_memcpy = omap_dma_prep_dma_memcpy;
1698 	od->ddev.device_prep_interleaved_dma = omap_dma_prep_dma_interleaved;
1699 	od->ddev.device_config = omap_dma_slave_config;
1700 	od->ddev.device_pause = omap_dma_pause;
1701 	od->ddev.device_resume = omap_dma_resume;
1702 	od->ddev.device_terminate_all = omap_dma_terminate_all;
1703 	od->ddev.device_synchronize = omap_dma_synchronize;
1704 	od->ddev.src_addr_widths = OMAP_DMA_BUSWIDTHS;
1705 	od->ddev.dst_addr_widths = OMAP_DMA_BUSWIDTHS;
1706 	od->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1707 	if (__dma_omap15xx(od->plat->dma_attr))
1708 		od->ddev.residue_granularity =
1709 				DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1710 	else
1711 		od->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1712 	od->ddev.max_burst = SZ_16M - 1; /* CCEN: 24bit unsigned */
1713 	od->ddev.dev = &pdev->dev;
1714 	INIT_LIST_HEAD(&od->ddev.channels);
1715 	mutex_init(&od->lch_lock);
1716 	spin_lock_init(&od->lock);
1717 	spin_lock_init(&od->irq_lock);
1718 
1719 	/* Number of DMA requests */
1720 	od->dma_requests = OMAP_SDMA_REQUESTS;
1721 	if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node,
1722 						      "dma-requests",
1723 						      &od->dma_requests)) {
1724 		dev_info(&pdev->dev,
1725 			 "Missing dma-requests property, using %u.\n",
1726 			 OMAP_SDMA_REQUESTS);
1727 	}
1728 
1729 	/* Number of available logical channels */
1730 	if (!pdev->dev.of_node) {
1731 		od->lch_count = od->plat->dma_attr->lch_count;
1732 		if (unlikely(!od->lch_count))
1733 			od->lch_count = OMAP_SDMA_CHANNELS;
1734 	} else if (of_property_read_u32(pdev->dev.of_node, "dma-channels",
1735 					&od->lch_count)) {
1736 		dev_info(&pdev->dev,
1737 			 "Missing dma-channels property, using %u.\n",
1738 			 OMAP_SDMA_CHANNELS);
1739 		od->lch_count = OMAP_SDMA_CHANNELS;
1740 	}
1741 
1742 	/* Mask of allowed logical channels */
1743 	if (pdev->dev.of_node && !of_property_read_u32(pdev->dev.of_node,
1744 						       "dma-channel-mask",
1745 						       &val)) {
1746 		/* Tag channels not in mask as reserved */
1747 		val = ~val;
1748 		bitmap_from_arr32(od->lch_bitmap, &val, od->lch_count);
1749 	}
1750 	if (od->plat->dma_attr->dev_caps & HS_CHANNELS_RESERVED)
1751 		bitmap_set(od->lch_bitmap, 0, 2);
1752 
1753 	od->lch_map = devm_kcalloc(&pdev->dev, od->lch_count,
1754 				   sizeof(*od->lch_map),
1755 				   GFP_KERNEL);
1756 	if (!od->lch_map)
1757 		return -ENOMEM;
1758 
1759 	for (i = 0; i < od->dma_requests; i++) {
1760 		rc = omap_dma_chan_init(od);
1761 		if (rc) {
1762 			omap_dma_free(od);
1763 			return rc;
1764 		}
1765 	}
1766 
1767 	irq = platform_get_irq(pdev, 1);
1768 	if (irq <= 0) {
1769 		dev_info(&pdev->dev, "failed to get L1 IRQ: %d\n", irq);
1770 		od->legacy = true;
1771 	} else {
1772 		/* Disable all interrupts */
1773 		od->irq_enable_mask = 0;
1774 		omap_dma_glbl_write(od, IRQENABLE_L1, 0);
1775 
1776 		rc = devm_request_irq(&pdev->dev, irq, omap_dma_irq,
1777 				      IRQF_SHARED, "omap-dma-engine", od);
1778 		if (rc) {
1779 			omap_dma_free(od);
1780 			return rc;
1781 		}
1782 	}
1783 
1784 	if (omap_dma_glbl_read(od, CAPS_0) & CAPS_0_SUPPORT_LL123)
1785 		od->ll123_supported = true;
1786 
1787 	od->ddev.filter.map = od->plat->slave_map;
1788 	od->ddev.filter.mapcnt = od->plat->slavecnt;
1789 	od->ddev.filter.fn = omap_dma_filter_fn;
1790 
1791 	if (od->ll123_supported) {
1792 		od->desc_pool = dma_pool_create(dev_name(&pdev->dev),
1793 						&pdev->dev,
1794 						sizeof(struct omap_type2_desc),
1795 						4, 0);
1796 		if (!od->desc_pool) {
1797 			dev_err(&pdev->dev,
1798 				"unable to allocate descriptor pool\n");
1799 			od->ll123_supported = false;
1800 		}
1801 	}
1802 
1803 	rc = dma_async_device_register(&od->ddev);
1804 	if (rc) {
1805 		pr_warn("OMAP-DMA: failed to register slave DMA engine device: %d\n",
1806 			rc);
1807 		omap_dma_free(od);
1808 		return rc;
1809 	}
1810 
1811 	platform_set_drvdata(pdev, od);
1812 
1813 	if (pdev->dev.of_node) {
1814 		omap_dma_info.dma_cap = od->ddev.cap_mask;
1815 
1816 		/* Device-tree DMA controller registration */
1817 		rc = of_dma_controller_register(pdev->dev.of_node,
1818 				of_dma_simple_xlate, &omap_dma_info);
1819 		if (rc) {
1820 			pr_warn("OMAP-DMA: failed to register DMA controller\n");
1821 			dma_async_device_unregister(&od->ddev);
1822 			omap_dma_free(od);
1823 		}
1824 	}
1825 
1826 	omap_dma_init_gcr(od, DMA_DEFAULT_ARB_RATE, DMA_DEFAULT_FIFO_DEPTH, 0);
1827 
1828 	if (od->cfg->needs_busy_check) {
1829 		od->nb.notifier_call = omap_dma_busy_notifier;
1830 		cpu_pm_register_notifier(&od->nb);
1831 	} else if (od->cfg->may_lose_context) {
1832 		od->nb.notifier_call = omap_dma_context_notifier;
1833 		cpu_pm_register_notifier(&od->nb);
1834 	}
1835 
1836 	dev_info(&pdev->dev, "OMAP DMA engine driver%s\n",
1837 		 od->ll123_supported ? " (LinkedList1/2/3 supported)" : "");
1838 
1839 	return rc;
1840 }
1841 
1842 static int omap_dma_remove(struct platform_device *pdev)
1843 {
1844 	struct omap_dmadev *od = platform_get_drvdata(pdev);
1845 	int irq;
1846 
1847 	if (od->cfg->may_lose_context)
1848 		cpu_pm_unregister_notifier(&od->nb);
1849 
1850 	if (pdev->dev.of_node)
1851 		of_dma_controller_free(pdev->dev.of_node);
1852 
1853 	irq = platform_get_irq(pdev, 1);
1854 	devm_free_irq(&pdev->dev, irq, od);
1855 
1856 	dma_async_device_unregister(&od->ddev);
1857 
1858 	if (!od->legacy) {
1859 		/* Disable all interrupts */
1860 		omap_dma_glbl_write(od, IRQENABLE_L0, 0);
1861 	}
1862 
1863 	if (od->ll123_supported)
1864 		dma_pool_destroy(od->desc_pool);
1865 
1866 	omap_dma_free(od);
1867 
1868 	return 0;
1869 }
1870 
1871 static const struct omap_dma_config omap2420_data = {
1872 	.lch_end = CCFN,
1873 	.rw_priority = true,
1874 	.needs_lch_clear = true,
1875 	.needs_busy_check = true,
1876 };
1877 
1878 static const struct omap_dma_config omap2430_data = {
1879 	.lch_end = CCFN,
1880 	.rw_priority = true,
1881 	.needs_lch_clear = true,
1882 };
1883 
1884 static const struct omap_dma_config omap3430_data = {
1885 	.lch_end = CCFN,
1886 	.rw_priority = true,
1887 	.needs_lch_clear = true,
1888 	.may_lose_context = true,
1889 };
1890 
1891 static const struct omap_dma_config omap3630_data = {
1892 	.lch_end = CCDN,
1893 	.rw_priority = true,
1894 	.needs_lch_clear = true,
1895 	.may_lose_context = true,
1896 };
1897 
1898 static const struct omap_dma_config omap4_data = {
1899 	.lch_end = CCDN,
1900 	.rw_priority = true,
1901 	.needs_lch_clear = true,
1902 };
1903 
1904 static const struct of_device_id omap_dma_match[] = {
1905 	{ .compatible = "ti,omap2420-sdma", .data = &omap2420_data, },
1906 	{ .compatible = "ti,omap2430-sdma", .data = &omap2430_data, },
1907 	{ .compatible = "ti,omap3430-sdma", .data = &omap3430_data, },
1908 	{ .compatible = "ti,omap3630-sdma", .data = &omap3630_data, },
1909 	{ .compatible = "ti,omap4430-sdma", .data = &omap4_data, },
1910 	{},
1911 };
1912 MODULE_DEVICE_TABLE(of, omap_dma_match);
1913 
1914 static struct platform_driver omap_dma_driver = {
1915 	.probe	= omap_dma_probe,
1916 	.remove	= omap_dma_remove,
1917 	.driver = {
1918 		.name = "omap-dma-engine",
1919 		.of_match_table = omap_dma_match,
1920 	},
1921 };
1922 
1923 static bool omap_dma_filter_fn(struct dma_chan *chan, void *param)
1924 {
1925 	if (chan->device->dev->driver == &omap_dma_driver.driver) {
1926 		struct omap_dmadev *od = to_omap_dma_dev(chan->device);
1927 		struct omap_chan *c = to_omap_dma_chan(chan);
1928 		unsigned req = *(unsigned *)param;
1929 
1930 		if (req <= od->dma_requests) {
1931 			c->dma_sig = req;
1932 			return true;
1933 		}
1934 	}
1935 	return false;
1936 }
1937 
1938 static int omap_dma_init(void)
1939 {
1940 	return platform_driver_register(&omap_dma_driver);
1941 }
1942 subsys_initcall(omap_dma_init);
1943 
1944 static void __exit omap_dma_exit(void)
1945 {
1946 	platform_driver_unregister(&omap_dma_driver);
1947 }
1948 module_exit(omap_dma_exit);
1949 
1950 MODULE_AUTHOR("Russell King");
1951 MODULE_LICENSE("GPL");
1952