xref: /openbmc/linux/drivers/dma/st_fdma.c (revision 726bd223)
1 /*
2  * DMA driver for STMicroelectronics STi FDMA controller
3  *
4  * Copyright (C) 2014 STMicroelectronics
5  *
6  * Author: Ludovic Barre <Ludovic.barre@st.com>
7  *	   Peter Griffin <peter.griffin@linaro.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/of_device.h>
18 #include <linux/of_dma.h>
19 #include <linux/platform_device.h>
20 #include <linux/interrupt.h>
21 #include <linux/remoteproc.h>
22 
23 #include "st_fdma.h"
24 
25 static inline struct st_fdma_chan *to_st_fdma_chan(struct dma_chan *c)
26 {
27 	return container_of(c, struct st_fdma_chan, vchan.chan);
28 }
29 
30 static struct st_fdma_desc *to_st_fdma_desc(struct virt_dma_desc *vd)
31 {
32 	return container_of(vd, struct st_fdma_desc, vdesc);
33 }
34 
35 static int st_fdma_dreq_get(struct st_fdma_chan *fchan)
36 {
37 	struct st_fdma_dev *fdev = fchan->fdev;
38 	u32 req_line_cfg = fchan->cfg.req_line;
39 	u32 dreq_line;
40 	int try = 0;
41 
42 	/*
43 	 * dreq_mask is shared for n channels of fdma, so all accesses must be
44 	 * atomic. if the dreq_mask is changed between ffz and set_bit,
45 	 * we retry
46 	 */
47 	do {
48 		if (fdev->dreq_mask == ~0L) {
49 			dev_err(fdev->dev, "No req lines available\n");
50 			return -EINVAL;
51 		}
52 
53 		if (try || req_line_cfg >= ST_FDMA_NR_DREQS) {
54 			dev_err(fdev->dev, "Invalid or used req line\n");
55 			return -EINVAL;
56 		} else {
57 			dreq_line = req_line_cfg;
58 		}
59 
60 		try++;
61 	} while (test_and_set_bit(dreq_line, &fdev->dreq_mask));
62 
63 	dev_dbg(fdev->dev, "get dreq_line:%d mask:%#lx\n",
64 		dreq_line, fdev->dreq_mask);
65 
66 	return dreq_line;
67 }
68 
69 static void st_fdma_dreq_put(struct st_fdma_chan *fchan)
70 {
71 	struct st_fdma_dev *fdev = fchan->fdev;
72 
73 	dev_dbg(fdev->dev, "put dreq_line:%#x\n", fchan->dreq_line);
74 	clear_bit(fchan->dreq_line, &fdev->dreq_mask);
75 }
76 
77 static void st_fdma_xfer_desc(struct st_fdma_chan *fchan)
78 {
79 	struct virt_dma_desc *vdesc;
80 	unsigned long nbytes, ch_cmd, cmd;
81 
82 	vdesc = vchan_next_desc(&fchan->vchan);
83 	if (!vdesc)
84 		return;
85 
86 	fchan->fdesc = to_st_fdma_desc(vdesc);
87 	nbytes = fchan->fdesc->node[0].desc->nbytes;
88 	cmd = FDMA_CMD_START(fchan->vchan.chan.chan_id);
89 	ch_cmd = fchan->fdesc->node[0].pdesc | FDMA_CH_CMD_STA_START;
90 
91 	/* start the channel for the descriptor */
92 	fnode_write(fchan, nbytes, FDMA_CNTN_OFST);
93 	fchan_write(fchan, ch_cmd, FDMA_CH_CMD_OFST);
94 	writel(cmd,
95 		fchan->fdev->slim_rproc->peri + FDMA_CMD_SET_OFST);
96 
97 	dev_dbg(fchan->fdev->dev, "start chan:%d\n", fchan->vchan.chan.chan_id);
98 }
99 
100 static void st_fdma_ch_sta_update(struct st_fdma_chan *fchan,
101 				  unsigned long int_sta)
102 {
103 	unsigned long ch_sta, ch_err;
104 	int ch_id = fchan->vchan.chan.chan_id;
105 	struct st_fdma_dev *fdev = fchan->fdev;
106 
107 	ch_sta = fchan_read(fchan, FDMA_CH_CMD_OFST);
108 	ch_err = ch_sta & FDMA_CH_CMD_ERR_MASK;
109 	ch_sta &= FDMA_CH_CMD_STA_MASK;
110 
111 	if (int_sta & FDMA_INT_STA_ERR) {
112 		dev_warn(fdev->dev, "chan:%d, error:%ld\n", ch_id, ch_err);
113 		fchan->status = DMA_ERROR;
114 		return;
115 	}
116 
117 	switch (ch_sta) {
118 	case FDMA_CH_CMD_STA_PAUSED:
119 		fchan->status = DMA_PAUSED;
120 		break;
121 
122 	case FDMA_CH_CMD_STA_RUNNING:
123 		fchan->status = DMA_IN_PROGRESS;
124 		break;
125 	}
126 }
127 
128 static irqreturn_t st_fdma_irq_handler(int irq, void *dev_id)
129 {
130 	struct st_fdma_dev *fdev = dev_id;
131 	irqreturn_t ret = IRQ_NONE;
132 	struct st_fdma_chan *fchan = &fdev->chans[0];
133 	unsigned long int_sta, clr;
134 
135 	int_sta = fdma_read(fdev, FDMA_INT_STA_OFST);
136 	clr = int_sta;
137 
138 	for (; int_sta != 0 ; int_sta >>= 2, fchan++) {
139 		if (!(int_sta & (FDMA_INT_STA_CH | FDMA_INT_STA_ERR)))
140 			continue;
141 
142 		spin_lock(&fchan->vchan.lock);
143 		st_fdma_ch_sta_update(fchan, int_sta);
144 
145 		if (fchan->fdesc) {
146 			if (!fchan->fdesc->iscyclic) {
147 				list_del(&fchan->fdesc->vdesc.node);
148 				vchan_cookie_complete(&fchan->fdesc->vdesc);
149 				fchan->fdesc = NULL;
150 				fchan->status = DMA_COMPLETE;
151 			} else {
152 				vchan_cyclic_callback(&fchan->fdesc->vdesc);
153 			}
154 
155 			/* Start the next descriptor (if available) */
156 			if (!fchan->fdesc)
157 				st_fdma_xfer_desc(fchan);
158 		}
159 
160 		spin_unlock(&fchan->vchan.lock);
161 		ret = IRQ_HANDLED;
162 	}
163 
164 	fdma_write(fdev, clr, FDMA_INT_CLR_OFST);
165 
166 	return ret;
167 }
168 
169 static struct dma_chan *st_fdma_of_xlate(struct of_phandle_args *dma_spec,
170 					 struct of_dma *ofdma)
171 {
172 	struct st_fdma_dev *fdev = ofdma->of_dma_data;
173 	struct dma_chan *chan;
174 	struct st_fdma_chan *fchan;
175 	int ret;
176 
177 	if (dma_spec->args_count < 1)
178 		return ERR_PTR(-EINVAL);
179 
180 	if (fdev->dma_device.dev->of_node != dma_spec->np)
181 		return ERR_PTR(-EINVAL);
182 
183 	ret = rproc_boot(fdev->slim_rproc->rproc);
184 	if (ret == -ENOENT)
185 		return ERR_PTR(-EPROBE_DEFER);
186 	else if (ret)
187 		return ERR_PTR(ret);
188 
189 	chan = dma_get_any_slave_channel(&fdev->dma_device);
190 	if (!chan)
191 		goto err_chan;
192 
193 	fchan = to_st_fdma_chan(chan);
194 
195 	fchan->cfg.of_node = dma_spec->np;
196 	fchan->cfg.req_line = dma_spec->args[0];
197 	fchan->cfg.req_ctrl = 0;
198 	fchan->cfg.type = ST_FDMA_TYPE_FREE_RUN;
199 
200 	if (dma_spec->args_count > 1)
201 		fchan->cfg.req_ctrl = dma_spec->args[1]
202 			& FDMA_REQ_CTRL_CFG_MASK;
203 
204 	if (dma_spec->args_count > 2)
205 		fchan->cfg.type = dma_spec->args[2];
206 
207 	if (fchan->cfg.type == ST_FDMA_TYPE_FREE_RUN) {
208 		fchan->dreq_line = 0;
209 	} else {
210 		fchan->dreq_line = st_fdma_dreq_get(fchan);
211 		if (IS_ERR_VALUE(fchan->dreq_line)) {
212 			chan = ERR_PTR(fchan->dreq_line);
213 			goto err_chan;
214 		}
215 	}
216 
217 	dev_dbg(fdev->dev, "xlate req_line:%d type:%d req_ctrl:%#lx\n",
218 		fchan->cfg.req_line, fchan->cfg.type, fchan->cfg.req_ctrl);
219 
220 	return chan;
221 
222 err_chan:
223 	rproc_shutdown(fdev->slim_rproc->rproc);
224 	return chan;
225 
226 }
227 
228 static void st_fdma_free_desc(struct virt_dma_desc *vdesc)
229 {
230 	struct st_fdma_desc *fdesc;
231 	int i;
232 
233 	fdesc = to_st_fdma_desc(vdesc);
234 	for (i = 0; i < fdesc->n_nodes; i++)
235 		dma_pool_free(fdesc->fchan->node_pool, fdesc->node[i].desc,
236 			      fdesc->node[i].pdesc);
237 	kfree(fdesc);
238 }
239 
240 static struct st_fdma_desc *st_fdma_alloc_desc(struct st_fdma_chan *fchan,
241 					       int sg_len)
242 {
243 	struct st_fdma_desc *fdesc;
244 	int i;
245 
246 	fdesc = kzalloc(sizeof(*fdesc) +
247 			sizeof(struct st_fdma_sw_node) * sg_len, GFP_NOWAIT);
248 	if (!fdesc)
249 		return NULL;
250 
251 	fdesc->fchan = fchan;
252 	fdesc->n_nodes = sg_len;
253 	for (i = 0; i < sg_len; i++) {
254 		fdesc->node[i].desc = dma_pool_alloc(fchan->node_pool,
255 				GFP_NOWAIT, &fdesc->node[i].pdesc);
256 		if (!fdesc->node[i].desc)
257 			goto err;
258 	}
259 	return fdesc;
260 
261 err:
262 	while (--i >= 0)
263 		dma_pool_free(fchan->node_pool, fdesc->node[i].desc,
264 			      fdesc->node[i].pdesc);
265 	kfree(fdesc);
266 	return NULL;
267 }
268 
269 static int st_fdma_alloc_chan_res(struct dma_chan *chan)
270 {
271 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
272 
273 	/* Create the dma pool for descriptor allocation */
274 	fchan->node_pool = dma_pool_create(dev_name(&chan->dev->device),
275 					    fchan->fdev->dev,
276 					    sizeof(struct st_fdma_hw_node),
277 					    __alignof__(struct st_fdma_hw_node),
278 					    0);
279 
280 	if (!fchan->node_pool) {
281 		dev_err(fchan->fdev->dev, "unable to allocate desc pool\n");
282 		return -ENOMEM;
283 	}
284 
285 	dev_dbg(fchan->fdev->dev, "alloc ch_id:%d type:%d\n",
286 		fchan->vchan.chan.chan_id, fchan->cfg.type);
287 
288 	return 0;
289 }
290 
291 static void st_fdma_free_chan_res(struct dma_chan *chan)
292 {
293 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
294 	struct rproc *rproc = fchan->fdev->slim_rproc->rproc;
295 	unsigned long flags;
296 
297 	LIST_HEAD(head);
298 
299 	dev_dbg(fchan->fdev->dev, "%s: freeing chan:%d\n",
300 		__func__, fchan->vchan.chan.chan_id);
301 
302 	if (fchan->cfg.type != ST_FDMA_TYPE_FREE_RUN)
303 		st_fdma_dreq_put(fchan);
304 
305 	spin_lock_irqsave(&fchan->vchan.lock, flags);
306 	fchan->fdesc = NULL;
307 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
308 
309 	dma_pool_destroy(fchan->node_pool);
310 	fchan->node_pool = NULL;
311 	memset(&fchan->cfg, 0, sizeof(struct st_fdma_cfg));
312 
313 	rproc_shutdown(rproc);
314 }
315 
316 static struct dma_async_tx_descriptor *st_fdma_prep_dma_memcpy(
317 	struct dma_chan *chan,	dma_addr_t dst, dma_addr_t src,
318 	size_t len, unsigned long flags)
319 {
320 	struct st_fdma_chan *fchan;
321 	struct st_fdma_desc *fdesc;
322 	struct st_fdma_hw_node *hw_node;
323 
324 	if (!len)
325 		return NULL;
326 
327 	fchan = to_st_fdma_chan(chan);
328 
329 	/* We only require a single descriptor */
330 	fdesc = st_fdma_alloc_desc(fchan, 1);
331 	if (!fdesc) {
332 		dev_err(fchan->fdev->dev, "no memory for desc\n");
333 		return NULL;
334 	}
335 
336 	hw_node = fdesc->node[0].desc;
337 	hw_node->next = 0;
338 	hw_node->control = FDMA_NODE_CTRL_REQ_MAP_FREE_RUN;
339 	hw_node->control |= FDMA_NODE_CTRL_SRC_INCR;
340 	hw_node->control |= FDMA_NODE_CTRL_DST_INCR;
341 	hw_node->control |= FDMA_NODE_CTRL_INT_EON;
342 	hw_node->nbytes = len;
343 	hw_node->saddr = src;
344 	hw_node->daddr = dst;
345 	hw_node->generic.length = len;
346 	hw_node->generic.sstride = 0;
347 	hw_node->generic.dstride = 0;
348 
349 	return vchan_tx_prep(&fchan->vchan, &fdesc->vdesc, flags);
350 }
351 
352 static int config_reqctrl(struct st_fdma_chan *fchan,
353 			  enum dma_transfer_direction direction)
354 {
355 	u32 maxburst = 0, addr = 0;
356 	enum dma_slave_buswidth width;
357 	int ch_id = fchan->vchan.chan.chan_id;
358 	struct st_fdma_dev *fdev = fchan->fdev;
359 
360 	switch (direction) {
361 
362 	case DMA_DEV_TO_MEM:
363 		fchan->cfg.req_ctrl &= ~FDMA_REQ_CTRL_WNR;
364 		maxburst = fchan->scfg.src_maxburst;
365 		width = fchan->scfg.src_addr_width;
366 		addr = fchan->scfg.src_addr;
367 		break;
368 
369 	case DMA_MEM_TO_DEV:
370 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_WNR;
371 		maxburst = fchan->scfg.dst_maxburst;
372 		width = fchan->scfg.dst_addr_width;
373 		addr = fchan->scfg.dst_addr;
374 		break;
375 
376 	default:
377 		return -EINVAL;
378 	}
379 
380 	fchan->cfg.req_ctrl &= ~FDMA_REQ_CTRL_OPCODE_MASK;
381 
382 	switch (width) {
383 
384 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
385 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST1;
386 		break;
387 
388 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
389 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST2;
390 		break;
391 
392 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
393 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST4;
394 		break;
395 
396 	case DMA_SLAVE_BUSWIDTH_8_BYTES:
397 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST8;
398 		break;
399 
400 	default:
401 		return -EINVAL;
402 	}
403 
404 	fchan->cfg.req_ctrl &= ~FDMA_REQ_CTRL_NUM_OPS_MASK;
405 	fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_NUM_OPS(maxburst-1);
406 	dreq_write(fchan, fchan->cfg.req_ctrl, FDMA_REQ_CTRL_OFST);
407 
408 	fchan->cfg.dev_addr = addr;
409 	fchan->cfg.dir = direction;
410 
411 	dev_dbg(fdev->dev, "chan:%d config_reqctrl:%#x req_ctrl:%#lx\n",
412 		ch_id, addr, fchan->cfg.req_ctrl);
413 
414 	return 0;
415 }
416 
417 static void fill_hw_node(struct st_fdma_hw_node *hw_node,
418 			struct st_fdma_chan *fchan,
419 			enum dma_transfer_direction direction)
420 {
421 	if (direction == DMA_MEM_TO_DEV) {
422 		hw_node->control |= FDMA_NODE_CTRL_SRC_INCR;
423 		hw_node->control |= FDMA_NODE_CTRL_DST_STATIC;
424 		hw_node->daddr = fchan->cfg.dev_addr;
425 	} else {
426 		hw_node->control |= FDMA_NODE_CTRL_SRC_STATIC;
427 		hw_node->control |= FDMA_NODE_CTRL_DST_INCR;
428 		hw_node->saddr = fchan->cfg.dev_addr;
429 	}
430 
431 	hw_node->generic.sstride = 0;
432 	hw_node->generic.dstride = 0;
433 }
434 
435 static inline struct st_fdma_chan *st_fdma_prep_common(struct dma_chan *chan,
436 		size_t len, enum dma_transfer_direction direction)
437 {
438 	struct st_fdma_chan *fchan;
439 
440 	if (!chan || !len)
441 		return NULL;
442 
443 	fchan = to_st_fdma_chan(chan);
444 
445 	if (!is_slave_direction(direction)) {
446 		dev_err(fchan->fdev->dev, "bad direction?\n");
447 		return NULL;
448 	}
449 
450 	return fchan;
451 }
452 
453 static struct dma_async_tx_descriptor *st_fdma_prep_dma_cyclic(
454 		struct dma_chan *chan, dma_addr_t buf_addr, size_t len,
455 		size_t period_len, enum dma_transfer_direction direction,
456 		unsigned long flags)
457 {
458 	struct st_fdma_chan *fchan;
459 	struct st_fdma_desc *fdesc;
460 	int sg_len, i;
461 
462 	fchan = st_fdma_prep_common(chan, len, direction);
463 	if (!fchan)
464 		return NULL;
465 
466 	if (!period_len)
467 		return NULL;
468 
469 	if (config_reqctrl(fchan, direction)) {
470 		dev_err(fchan->fdev->dev, "bad width or direction\n");
471 		return NULL;
472 	}
473 
474 	/* the buffer length must be a multiple of period_len */
475 	if (len % period_len != 0) {
476 		dev_err(fchan->fdev->dev, "len is not multiple of period\n");
477 		return NULL;
478 	}
479 
480 	sg_len = len / period_len;
481 	fdesc = st_fdma_alloc_desc(fchan, sg_len);
482 	if (!fdesc) {
483 		dev_err(fchan->fdev->dev, "no memory for desc\n");
484 		return NULL;
485 	}
486 
487 	fdesc->iscyclic = true;
488 
489 	for (i = 0; i < sg_len; i++) {
490 		struct st_fdma_hw_node *hw_node = fdesc->node[i].desc;
491 
492 		hw_node->next = fdesc->node[(i + 1) % sg_len].pdesc;
493 
494 		hw_node->control =
495 			FDMA_NODE_CTRL_REQ_MAP_DREQ(fchan->dreq_line);
496 		hw_node->control |= FDMA_NODE_CTRL_INT_EON;
497 
498 		fill_hw_node(hw_node, fchan, direction);
499 
500 		if (direction == DMA_MEM_TO_DEV)
501 			hw_node->saddr = buf_addr + (i * period_len);
502 		else
503 			hw_node->daddr = buf_addr + (i * period_len);
504 
505 		hw_node->nbytes = period_len;
506 		hw_node->generic.length = period_len;
507 	}
508 
509 	return vchan_tx_prep(&fchan->vchan, &fdesc->vdesc, flags);
510 }
511 
512 static struct dma_async_tx_descriptor *st_fdma_prep_slave_sg(
513 		struct dma_chan *chan, struct scatterlist *sgl,
514 		unsigned int sg_len, enum dma_transfer_direction direction,
515 		unsigned long flags, void *context)
516 {
517 	struct st_fdma_chan *fchan;
518 	struct st_fdma_desc *fdesc;
519 	struct st_fdma_hw_node *hw_node;
520 	struct scatterlist *sg;
521 	int i;
522 
523 	fchan = st_fdma_prep_common(chan, sg_len, direction);
524 	if (!fchan)
525 		return NULL;
526 
527 	if (!sgl)
528 		return NULL;
529 
530 	fdesc = st_fdma_alloc_desc(fchan, sg_len);
531 	if (!fdesc) {
532 		dev_err(fchan->fdev->dev, "no memory for desc\n");
533 		return NULL;
534 	}
535 
536 	fdesc->iscyclic = false;
537 
538 	for_each_sg(sgl, sg, sg_len, i) {
539 		hw_node = fdesc->node[i].desc;
540 
541 		hw_node->next = fdesc->node[(i + 1) % sg_len].pdesc;
542 		hw_node->control = FDMA_NODE_CTRL_REQ_MAP_DREQ(fchan->dreq_line);
543 
544 		fill_hw_node(hw_node, fchan, direction);
545 
546 		if (direction == DMA_MEM_TO_DEV)
547 			hw_node->saddr = sg_dma_address(sg);
548 		else
549 			hw_node->daddr = sg_dma_address(sg);
550 
551 		hw_node->nbytes = sg_dma_len(sg);
552 		hw_node->generic.length = sg_dma_len(sg);
553 	}
554 
555 	/* interrupt at end of last node */
556 	hw_node->control |= FDMA_NODE_CTRL_INT_EON;
557 
558 	return vchan_tx_prep(&fchan->vchan, &fdesc->vdesc, flags);
559 }
560 
561 static size_t st_fdma_desc_residue(struct st_fdma_chan *fchan,
562 				   struct virt_dma_desc *vdesc,
563 				   bool in_progress)
564 {
565 	struct st_fdma_desc *fdesc = fchan->fdesc;
566 	size_t residue = 0;
567 	dma_addr_t cur_addr = 0;
568 	int i;
569 
570 	if (in_progress) {
571 		cur_addr = fchan_read(fchan, FDMA_CH_CMD_OFST);
572 		cur_addr &= FDMA_CH_CMD_DATA_MASK;
573 	}
574 
575 	for (i = fchan->fdesc->n_nodes - 1 ; i >= 0; i--) {
576 		if (cur_addr == fdesc->node[i].pdesc) {
577 			residue += fnode_read(fchan, FDMA_CNTN_OFST);
578 			break;
579 		}
580 		residue += fdesc->node[i].desc->nbytes;
581 	}
582 
583 	return residue;
584 }
585 
586 static enum dma_status st_fdma_tx_status(struct dma_chan *chan,
587 					 dma_cookie_t cookie,
588 					 struct dma_tx_state *txstate)
589 {
590 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
591 	struct virt_dma_desc *vd;
592 	enum dma_status ret;
593 	unsigned long flags;
594 
595 	ret = dma_cookie_status(chan, cookie, txstate);
596 	if (ret == DMA_COMPLETE || !txstate)
597 		return ret;
598 
599 	spin_lock_irqsave(&fchan->vchan.lock, flags);
600 	vd = vchan_find_desc(&fchan->vchan, cookie);
601 	if (fchan->fdesc && cookie == fchan->fdesc->vdesc.tx.cookie)
602 		txstate->residue = st_fdma_desc_residue(fchan, vd, true);
603 	else if (vd)
604 		txstate->residue = st_fdma_desc_residue(fchan, vd, false);
605 	else
606 		txstate->residue = 0;
607 
608 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
609 
610 	return ret;
611 }
612 
613 static void st_fdma_issue_pending(struct dma_chan *chan)
614 {
615 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
616 	unsigned long flags;
617 
618 	spin_lock_irqsave(&fchan->vchan.lock, flags);
619 
620 	if (vchan_issue_pending(&fchan->vchan) && !fchan->fdesc)
621 		st_fdma_xfer_desc(fchan);
622 
623 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
624 }
625 
626 static int st_fdma_pause(struct dma_chan *chan)
627 {
628 	unsigned long flags;
629 	LIST_HEAD(head);
630 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
631 	int ch_id = fchan->vchan.chan.chan_id;
632 	unsigned long cmd = FDMA_CMD_PAUSE(ch_id);
633 
634 	dev_dbg(fchan->fdev->dev, "pause chan:%d\n", ch_id);
635 
636 	spin_lock_irqsave(&fchan->vchan.lock, flags);
637 	if (fchan->fdesc)
638 		fdma_write(fchan->fdev, cmd, FDMA_CMD_SET_OFST);
639 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
640 
641 	return 0;
642 }
643 
644 static int st_fdma_resume(struct dma_chan *chan)
645 {
646 	unsigned long flags;
647 	unsigned long val;
648 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
649 	int ch_id = fchan->vchan.chan.chan_id;
650 
651 	dev_dbg(fchan->fdev->dev, "resume chan:%d\n", ch_id);
652 
653 	spin_lock_irqsave(&fchan->vchan.lock, flags);
654 	if (fchan->fdesc) {
655 		val = fchan_read(fchan, FDMA_CH_CMD_OFST);
656 		val &= FDMA_CH_CMD_DATA_MASK;
657 		fchan_write(fchan, val, FDMA_CH_CMD_OFST);
658 	}
659 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
660 
661 	return 0;
662 }
663 
664 static int st_fdma_terminate_all(struct dma_chan *chan)
665 {
666 	unsigned long flags;
667 	LIST_HEAD(head);
668 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
669 	int ch_id = fchan->vchan.chan.chan_id;
670 	unsigned long cmd = FDMA_CMD_PAUSE(ch_id);
671 
672 	dev_dbg(fchan->fdev->dev, "terminate chan:%d\n", ch_id);
673 
674 	spin_lock_irqsave(&fchan->vchan.lock, flags);
675 	fdma_write(fchan->fdev, cmd, FDMA_CMD_SET_OFST);
676 	fchan->fdesc = NULL;
677 	vchan_get_all_descriptors(&fchan->vchan, &head);
678 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
679 	vchan_dma_desc_free_list(&fchan->vchan, &head);
680 
681 	return 0;
682 }
683 
684 static int st_fdma_slave_config(struct dma_chan *chan,
685 				struct dma_slave_config *slave_cfg)
686 {
687 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
688 
689 	memcpy(&fchan->scfg, slave_cfg, sizeof(fchan->scfg));
690 	return 0;
691 }
692 
693 static const struct st_fdma_driverdata fdma_mpe31_stih407_11 = {
694 	.name = "STiH407",
695 	.id = 0,
696 };
697 
698 static const struct st_fdma_driverdata fdma_mpe31_stih407_12 = {
699 	.name = "STiH407",
700 	.id = 1,
701 };
702 
703 static const struct st_fdma_driverdata fdma_mpe31_stih407_13 = {
704 	.name = "STiH407",
705 	.id = 2,
706 };
707 
708 static const struct of_device_id st_fdma_match[] = {
709 	{ .compatible = "st,stih407-fdma-mpe31-11"
710 	  , .data = &fdma_mpe31_stih407_11 },
711 	{ .compatible = "st,stih407-fdma-mpe31-12"
712 	  , .data = &fdma_mpe31_stih407_12 },
713 	{ .compatible = "st,stih407-fdma-mpe31-13"
714 	  , .data = &fdma_mpe31_stih407_13 },
715 	{},
716 };
717 MODULE_DEVICE_TABLE(of, st_fdma_match);
718 
719 static int st_fdma_parse_dt(struct platform_device *pdev,
720 			const struct st_fdma_driverdata *drvdata,
721 			struct st_fdma_dev *fdev)
722 {
723 	snprintf(fdev->fw_name, FW_NAME_SIZE, "fdma_%s_%d.elf",
724 		drvdata->name, drvdata->id);
725 
726 	return of_property_read_u32(pdev->dev.of_node, "dma-channels",
727 				    &fdev->nr_channels);
728 }
729 #define FDMA_DMA_BUSWIDTHS	(BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
730 				 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
731 				 BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
732 				 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
733 
734 static void st_fdma_free(struct st_fdma_dev *fdev)
735 {
736 	struct st_fdma_chan *fchan;
737 	int i;
738 
739 	for (i = 0; i < fdev->nr_channels; i++) {
740 		fchan = &fdev->chans[i];
741 		list_del(&fchan->vchan.chan.device_node);
742 		tasklet_kill(&fchan->vchan.task);
743 	}
744 }
745 
746 static int st_fdma_probe(struct platform_device *pdev)
747 {
748 	struct st_fdma_dev *fdev;
749 	const struct of_device_id *match;
750 	struct device_node *np = pdev->dev.of_node;
751 	const struct st_fdma_driverdata *drvdata;
752 	int ret, i;
753 
754 	match = of_match_device((st_fdma_match), &pdev->dev);
755 	if (!match || !match->data) {
756 		dev_err(&pdev->dev, "No device match found\n");
757 		return -ENODEV;
758 	}
759 
760 	drvdata = match->data;
761 
762 	fdev = devm_kzalloc(&pdev->dev, sizeof(*fdev), GFP_KERNEL);
763 	if (!fdev)
764 		return -ENOMEM;
765 
766 	ret = st_fdma_parse_dt(pdev, drvdata, fdev);
767 	if (ret) {
768 		dev_err(&pdev->dev, "unable to find platform data\n");
769 		goto err;
770 	}
771 
772 	fdev->chans = devm_kcalloc(&pdev->dev, fdev->nr_channels,
773 				   sizeof(struct st_fdma_chan), GFP_KERNEL);
774 	if (!fdev->chans)
775 		return -ENOMEM;
776 
777 	fdev->dev = &pdev->dev;
778 	fdev->drvdata = drvdata;
779 	platform_set_drvdata(pdev, fdev);
780 
781 	fdev->irq = platform_get_irq(pdev, 0);
782 	if (fdev->irq < 0) {
783 		dev_err(&pdev->dev, "Failed to get irq resource\n");
784 		return -EINVAL;
785 	}
786 
787 	ret = devm_request_irq(&pdev->dev, fdev->irq, st_fdma_irq_handler, 0,
788 			       dev_name(&pdev->dev), fdev);
789 	if (ret) {
790 		dev_err(&pdev->dev, "Failed to request irq (%d)\n", ret);
791 		goto err;
792 	}
793 
794 	fdev->slim_rproc = st_slim_rproc_alloc(pdev, fdev->fw_name);
795 	if (IS_ERR(fdev->slim_rproc)) {
796 		ret = PTR_ERR(fdev->slim_rproc);
797 		dev_err(&pdev->dev, "slim_rproc_alloc failed (%d)\n", ret);
798 		goto err;
799 	}
800 
801 	/* Initialise list of FDMA channels */
802 	INIT_LIST_HEAD(&fdev->dma_device.channels);
803 	for (i = 0; i < fdev->nr_channels; i++) {
804 		struct st_fdma_chan *fchan = &fdev->chans[i];
805 
806 		fchan->fdev = fdev;
807 		fchan->vchan.desc_free = st_fdma_free_desc;
808 		vchan_init(&fchan->vchan, &fdev->dma_device);
809 	}
810 
811 	/* Initialise the FDMA dreq (reserve 0 & 31 for FDMA use) */
812 	fdev->dreq_mask = BIT(0) | BIT(31);
813 
814 	dma_cap_set(DMA_SLAVE, fdev->dma_device.cap_mask);
815 	dma_cap_set(DMA_CYCLIC, fdev->dma_device.cap_mask);
816 	dma_cap_set(DMA_MEMCPY, fdev->dma_device.cap_mask);
817 
818 	fdev->dma_device.dev = &pdev->dev;
819 	fdev->dma_device.device_alloc_chan_resources = st_fdma_alloc_chan_res;
820 	fdev->dma_device.device_free_chan_resources = st_fdma_free_chan_res;
821 	fdev->dma_device.device_prep_dma_cyclic	= st_fdma_prep_dma_cyclic;
822 	fdev->dma_device.device_prep_slave_sg = st_fdma_prep_slave_sg;
823 	fdev->dma_device.device_prep_dma_memcpy = st_fdma_prep_dma_memcpy;
824 	fdev->dma_device.device_tx_status = st_fdma_tx_status;
825 	fdev->dma_device.device_issue_pending = st_fdma_issue_pending;
826 	fdev->dma_device.device_terminate_all = st_fdma_terminate_all;
827 	fdev->dma_device.device_config = st_fdma_slave_config;
828 	fdev->dma_device.device_pause = st_fdma_pause;
829 	fdev->dma_device.device_resume = st_fdma_resume;
830 
831 	fdev->dma_device.src_addr_widths = FDMA_DMA_BUSWIDTHS;
832 	fdev->dma_device.dst_addr_widths = FDMA_DMA_BUSWIDTHS;
833 	fdev->dma_device.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
834 	fdev->dma_device.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
835 
836 	ret = dma_async_device_register(&fdev->dma_device);
837 	if (ret) {
838 		dev_err(&pdev->dev,
839 			"Failed to register DMA device (%d)\n", ret);
840 		goto err_rproc;
841 	}
842 
843 	ret = of_dma_controller_register(np, st_fdma_of_xlate, fdev);
844 	if (ret) {
845 		dev_err(&pdev->dev,
846 			"Failed to register controller (%d)\n", ret);
847 		goto err_dma_dev;
848 	}
849 
850 	dev_info(&pdev->dev, "ST FDMA engine driver, irq:%d\n", fdev->irq);
851 
852 	return 0;
853 
854 err_dma_dev:
855 	dma_async_device_unregister(&fdev->dma_device);
856 err_rproc:
857 	st_fdma_free(fdev);
858 	st_slim_rproc_put(fdev->slim_rproc);
859 err:
860 	return ret;
861 }
862 
863 static int st_fdma_remove(struct platform_device *pdev)
864 {
865 	struct st_fdma_dev *fdev = platform_get_drvdata(pdev);
866 
867 	devm_free_irq(&pdev->dev, fdev->irq, fdev);
868 	st_slim_rproc_put(fdev->slim_rproc);
869 	of_dma_controller_free(pdev->dev.of_node);
870 	dma_async_device_unregister(&fdev->dma_device);
871 
872 	return 0;
873 }
874 
875 static struct platform_driver st_fdma_platform_driver = {
876 	.driver = {
877 		.name = DRIVER_NAME,
878 		.of_match_table = st_fdma_match,
879 	},
880 	.probe = st_fdma_probe,
881 	.remove = st_fdma_remove,
882 };
883 module_platform_driver(st_fdma_platform_driver);
884 
885 MODULE_LICENSE("GPL v2");
886 MODULE_DESCRIPTION("STMicroelectronics FDMA engine driver");
887 MODULE_AUTHOR("Ludovic.barre <Ludovic.barre@st.com>");
888 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
889 MODULE_ALIAS("platform: " DRIVER_NAME);
890