xref: /linux/drivers/dma/st_fdma.c (revision aa23aa55166c2865ac430168c4b9d405cf8c6980)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DMA driver for STMicroelectronics STi FDMA controller
4  *
5  * Copyright (C) 2014 STMicroelectronics
6  *
7  * Author: Ludovic Barre <Ludovic.barre@st.com>
8  *	   Peter Griffin <peter.griffin@linaro.org>
9  */
10 
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/of_device.h>
14 #include <linux/of_dma.h>
15 #include <linux/platform_device.h>
16 #include <linux/interrupt.h>
17 #include <linux/remoteproc.h>
18 
19 #include "st_fdma.h"
20 
21 static inline struct st_fdma_chan *to_st_fdma_chan(struct dma_chan *c)
22 {
23 	return container_of(c, struct st_fdma_chan, vchan.chan);
24 }
25 
26 static struct st_fdma_desc *to_st_fdma_desc(struct virt_dma_desc *vd)
27 {
28 	return container_of(vd, struct st_fdma_desc, vdesc);
29 }
30 
31 static int st_fdma_dreq_get(struct st_fdma_chan *fchan)
32 {
33 	struct st_fdma_dev *fdev = fchan->fdev;
34 	u32 req_line_cfg = fchan->cfg.req_line;
35 	u32 dreq_line;
36 	int try = 0;
37 
38 	/*
39 	 * dreq_mask is shared for n channels of fdma, so all accesses must be
40 	 * atomic. if the dreq_mask is changed between ffz and set_bit,
41 	 * we retry
42 	 */
43 	do {
44 		if (fdev->dreq_mask == ~0L) {
45 			dev_err(fdev->dev, "No req lines available\n");
46 			return -EINVAL;
47 		}
48 
49 		if (try || req_line_cfg >= ST_FDMA_NR_DREQS) {
50 			dev_err(fdev->dev, "Invalid or used req line\n");
51 			return -EINVAL;
52 		} else {
53 			dreq_line = req_line_cfg;
54 		}
55 
56 		try++;
57 	} while (test_and_set_bit(dreq_line, &fdev->dreq_mask));
58 
59 	dev_dbg(fdev->dev, "get dreq_line:%d mask:%#lx\n",
60 		dreq_line, fdev->dreq_mask);
61 
62 	return dreq_line;
63 }
64 
65 static void st_fdma_dreq_put(struct st_fdma_chan *fchan)
66 {
67 	struct st_fdma_dev *fdev = fchan->fdev;
68 
69 	dev_dbg(fdev->dev, "put dreq_line:%#x\n", fchan->dreq_line);
70 	clear_bit(fchan->dreq_line, &fdev->dreq_mask);
71 }
72 
73 static void st_fdma_xfer_desc(struct st_fdma_chan *fchan)
74 {
75 	struct virt_dma_desc *vdesc;
76 	unsigned long nbytes, ch_cmd, cmd;
77 
78 	vdesc = vchan_next_desc(&fchan->vchan);
79 	if (!vdesc)
80 		return;
81 
82 	fchan->fdesc = to_st_fdma_desc(vdesc);
83 	nbytes = fchan->fdesc->node[0].desc->nbytes;
84 	cmd = FDMA_CMD_START(fchan->vchan.chan.chan_id);
85 	ch_cmd = fchan->fdesc->node[0].pdesc | FDMA_CH_CMD_STA_START;
86 
87 	/* start the channel for the descriptor */
88 	fnode_write(fchan, nbytes, FDMA_CNTN_OFST);
89 	fchan_write(fchan, ch_cmd, FDMA_CH_CMD_OFST);
90 	writel(cmd,
91 		fchan->fdev->slim_rproc->peri + FDMA_CMD_SET_OFST);
92 
93 	dev_dbg(fchan->fdev->dev, "start chan:%d\n", fchan->vchan.chan.chan_id);
94 }
95 
96 static void st_fdma_ch_sta_update(struct st_fdma_chan *fchan,
97 				  unsigned long int_sta)
98 {
99 	unsigned long ch_sta, ch_err;
100 	int ch_id = fchan->vchan.chan.chan_id;
101 	struct st_fdma_dev *fdev = fchan->fdev;
102 
103 	ch_sta = fchan_read(fchan, FDMA_CH_CMD_OFST);
104 	ch_err = ch_sta & FDMA_CH_CMD_ERR_MASK;
105 	ch_sta &= FDMA_CH_CMD_STA_MASK;
106 
107 	if (int_sta & FDMA_INT_STA_ERR) {
108 		dev_warn(fdev->dev, "chan:%d, error:%ld\n", ch_id, ch_err);
109 		fchan->status = DMA_ERROR;
110 		return;
111 	}
112 
113 	switch (ch_sta) {
114 	case FDMA_CH_CMD_STA_PAUSED:
115 		fchan->status = DMA_PAUSED;
116 		break;
117 
118 	case FDMA_CH_CMD_STA_RUNNING:
119 		fchan->status = DMA_IN_PROGRESS;
120 		break;
121 	}
122 }
123 
124 static irqreturn_t st_fdma_irq_handler(int irq, void *dev_id)
125 {
126 	struct st_fdma_dev *fdev = dev_id;
127 	irqreturn_t ret = IRQ_NONE;
128 	struct st_fdma_chan *fchan = &fdev->chans[0];
129 	unsigned long int_sta, clr;
130 
131 	int_sta = fdma_read(fdev, FDMA_INT_STA_OFST);
132 	clr = int_sta;
133 
134 	for (; int_sta != 0 ; int_sta >>= 2, fchan++) {
135 		if (!(int_sta & (FDMA_INT_STA_CH | FDMA_INT_STA_ERR)))
136 			continue;
137 
138 		spin_lock(&fchan->vchan.lock);
139 		st_fdma_ch_sta_update(fchan, int_sta);
140 
141 		if (fchan->fdesc) {
142 			if (!fchan->fdesc->iscyclic) {
143 				list_del(&fchan->fdesc->vdesc.node);
144 				vchan_cookie_complete(&fchan->fdesc->vdesc);
145 				fchan->fdesc = NULL;
146 				fchan->status = DMA_COMPLETE;
147 			} else {
148 				vchan_cyclic_callback(&fchan->fdesc->vdesc);
149 			}
150 
151 			/* Start the next descriptor (if available) */
152 			if (!fchan->fdesc)
153 				st_fdma_xfer_desc(fchan);
154 		}
155 
156 		spin_unlock(&fchan->vchan.lock);
157 		ret = IRQ_HANDLED;
158 	}
159 
160 	fdma_write(fdev, clr, FDMA_INT_CLR_OFST);
161 
162 	return ret;
163 }
164 
165 static struct dma_chan *st_fdma_of_xlate(struct of_phandle_args *dma_spec,
166 					 struct of_dma *ofdma)
167 {
168 	struct st_fdma_dev *fdev = ofdma->of_dma_data;
169 	struct dma_chan *chan;
170 	struct st_fdma_chan *fchan;
171 	int ret;
172 
173 	if (dma_spec->args_count < 1)
174 		return ERR_PTR(-EINVAL);
175 
176 	if (fdev->dma_device.dev->of_node != dma_spec->np)
177 		return ERR_PTR(-EINVAL);
178 
179 	ret = rproc_boot(fdev->slim_rproc->rproc);
180 	if (ret == -ENOENT)
181 		return ERR_PTR(-EPROBE_DEFER);
182 	else if (ret)
183 		return ERR_PTR(ret);
184 
185 	chan = dma_get_any_slave_channel(&fdev->dma_device);
186 	if (!chan)
187 		goto err_chan;
188 
189 	fchan = to_st_fdma_chan(chan);
190 
191 	fchan->cfg.of_node = dma_spec->np;
192 	fchan->cfg.req_line = dma_spec->args[0];
193 	fchan->cfg.req_ctrl = 0;
194 	fchan->cfg.type = ST_FDMA_TYPE_FREE_RUN;
195 
196 	if (dma_spec->args_count > 1)
197 		fchan->cfg.req_ctrl = dma_spec->args[1]
198 			& FDMA_REQ_CTRL_CFG_MASK;
199 
200 	if (dma_spec->args_count > 2)
201 		fchan->cfg.type = dma_spec->args[2];
202 
203 	if (fchan->cfg.type == ST_FDMA_TYPE_FREE_RUN) {
204 		fchan->dreq_line = 0;
205 	} else {
206 		fchan->dreq_line = st_fdma_dreq_get(fchan);
207 		if (IS_ERR_VALUE(fchan->dreq_line)) {
208 			chan = ERR_PTR(fchan->dreq_line);
209 			goto err_chan;
210 		}
211 	}
212 
213 	dev_dbg(fdev->dev, "xlate req_line:%d type:%d req_ctrl:%#lx\n",
214 		fchan->cfg.req_line, fchan->cfg.type, fchan->cfg.req_ctrl);
215 
216 	return chan;
217 
218 err_chan:
219 	rproc_shutdown(fdev->slim_rproc->rproc);
220 	return chan;
221 
222 }
223 
224 static void st_fdma_free_desc(struct virt_dma_desc *vdesc)
225 {
226 	struct st_fdma_desc *fdesc;
227 	int i;
228 
229 	fdesc = to_st_fdma_desc(vdesc);
230 	for (i = 0; i < fdesc->n_nodes; i++)
231 		dma_pool_free(fdesc->fchan->node_pool, fdesc->node[i].desc,
232 			      fdesc->node[i].pdesc);
233 	kfree(fdesc);
234 }
235 
236 static struct st_fdma_desc *st_fdma_alloc_desc(struct st_fdma_chan *fchan,
237 					       int sg_len)
238 {
239 	struct st_fdma_desc *fdesc;
240 	int i;
241 
242 	fdesc = kzalloc(struct_size(fdesc, node, sg_len), GFP_NOWAIT);
243 	if (!fdesc)
244 		return NULL;
245 
246 	fdesc->fchan = fchan;
247 	fdesc->n_nodes = sg_len;
248 	for (i = 0; i < sg_len; i++) {
249 		fdesc->node[i].desc = dma_pool_alloc(fchan->node_pool,
250 				GFP_NOWAIT, &fdesc->node[i].pdesc);
251 		if (!fdesc->node[i].desc)
252 			goto err;
253 	}
254 	return fdesc;
255 
256 err:
257 	while (--i >= 0)
258 		dma_pool_free(fchan->node_pool, fdesc->node[i].desc,
259 			      fdesc->node[i].pdesc);
260 	kfree(fdesc);
261 	return NULL;
262 }
263 
264 static int st_fdma_alloc_chan_res(struct dma_chan *chan)
265 {
266 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
267 
268 	/* Create the dma pool for descriptor allocation */
269 	fchan->node_pool = dma_pool_create(dev_name(&chan->dev->device),
270 					    fchan->fdev->dev,
271 					    sizeof(struct st_fdma_hw_node),
272 					    __alignof__(struct st_fdma_hw_node),
273 					    0);
274 
275 	if (!fchan->node_pool) {
276 		dev_err(fchan->fdev->dev, "unable to allocate desc pool\n");
277 		return -ENOMEM;
278 	}
279 
280 	dev_dbg(fchan->fdev->dev, "alloc ch_id:%d type:%d\n",
281 		fchan->vchan.chan.chan_id, fchan->cfg.type);
282 
283 	return 0;
284 }
285 
286 static void st_fdma_free_chan_res(struct dma_chan *chan)
287 {
288 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
289 	struct rproc *rproc = fchan->fdev->slim_rproc->rproc;
290 	unsigned long flags;
291 
292 	dev_dbg(fchan->fdev->dev, "%s: freeing chan:%d\n",
293 		__func__, fchan->vchan.chan.chan_id);
294 
295 	if (fchan->cfg.type != ST_FDMA_TYPE_FREE_RUN)
296 		st_fdma_dreq_put(fchan);
297 
298 	spin_lock_irqsave(&fchan->vchan.lock, flags);
299 	fchan->fdesc = NULL;
300 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
301 
302 	dma_pool_destroy(fchan->node_pool);
303 	fchan->node_pool = NULL;
304 	memset(&fchan->cfg, 0, sizeof(struct st_fdma_cfg));
305 
306 	rproc_shutdown(rproc);
307 }
308 
309 static struct dma_async_tx_descriptor *st_fdma_prep_dma_memcpy(
310 	struct dma_chan *chan,	dma_addr_t dst, dma_addr_t src,
311 	size_t len, unsigned long flags)
312 {
313 	struct st_fdma_chan *fchan;
314 	struct st_fdma_desc *fdesc;
315 	struct st_fdma_hw_node *hw_node;
316 
317 	if (!len)
318 		return NULL;
319 
320 	fchan = to_st_fdma_chan(chan);
321 
322 	/* We only require a single descriptor */
323 	fdesc = st_fdma_alloc_desc(fchan, 1);
324 	if (!fdesc) {
325 		dev_err(fchan->fdev->dev, "no memory for desc\n");
326 		return NULL;
327 	}
328 
329 	hw_node = fdesc->node[0].desc;
330 	hw_node->next = 0;
331 	hw_node->control = FDMA_NODE_CTRL_REQ_MAP_FREE_RUN;
332 	hw_node->control |= FDMA_NODE_CTRL_SRC_INCR;
333 	hw_node->control |= FDMA_NODE_CTRL_DST_INCR;
334 	hw_node->control |= FDMA_NODE_CTRL_INT_EON;
335 	hw_node->nbytes = len;
336 	hw_node->saddr = src;
337 	hw_node->daddr = dst;
338 	hw_node->generic.length = len;
339 	hw_node->generic.sstride = 0;
340 	hw_node->generic.dstride = 0;
341 
342 	return vchan_tx_prep(&fchan->vchan, &fdesc->vdesc, flags);
343 }
344 
345 static int config_reqctrl(struct st_fdma_chan *fchan,
346 			  enum dma_transfer_direction direction)
347 {
348 	u32 maxburst = 0, addr = 0;
349 	enum dma_slave_buswidth width;
350 	int ch_id = fchan->vchan.chan.chan_id;
351 	struct st_fdma_dev *fdev = fchan->fdev;
352 
353 	switch (direction) {
354 
355 	case DMA_DEV_TO_MEM:
356 		fchan->cfg.req_ctrl &= ~FDMA_REQ_CTRL_WNR;
357 		maxburst = fchan->scfg.src_maxburst;
358 		width = fchan->scfg.src_addr_width;
359 		addr = fchan->scfg.src_addr;
360 		break;
361 
362 	case DMA_MEM_TO_DEV:
363 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_WNR;
364 		maxburst = fchan->scfg.dst_maxburst;
365 		width = fchan->scfg.dst_addr_width;
366 		addr = fchan->scfg.dst_addr;
367 		break;
368 
369 	default:
370 		return -EINVAL;
371 	}
372 
373 	fchan->cfg.req_ctrl &= ~FDMA_REQ_CTRL_OPCODE_MASK;
374 
375 	switch (width) {
376 
377 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
378 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST1;
379 		break;
380 
381 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
382 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST2;
383 		break;
384 
385 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
386 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST4;
387 		break;
388 
389 	case DMA_SLAVE_BUSWIDTH_8_BYTES:
390 		fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_OPCODE_LD_ST8;
391 		break;
392 
393 	default:
394 		return -EINVAL;
395 	}
396 
397 	fchan->cfg.req_ctrl &= ~FDMA_REQ_CTRL_NUM_OPS_MASK;
398 	fchan->cfg.req_ctrl |= FDMA_REQ_CTRL_NUM_OPS(maxburst-1);
399 	dreq_write(fchan, fchan->cfg.req_ctrl, FDMA_REQ_CTRL_OFST);
400 
401 	fchan->cfg.dev_addr = addr;
402 	fchan->cfg.dir = direction;
403 
404 	dev_dbg(fdev->dev, "chan:%d config_reqctrl:%#x req_ctrl:%#lx\n",
405 		ch_id, addr, fchan->cfg.req_ctrl);
406 
407 	return 0;
408 }
409 
410 static void fill_hw_node(struct st_fdma_hw_node *hw_node,
411 			struct st_fdma_chan *fchan,
412 			enum dma_transfer_direction direction)
413 {
414 	if (direction == DMA_MEM_TO_DEV) {
415 		hw_node->control |= FDMA_NODE_CTRL_SRC_INCR;
416 		hw_node->control |= FDMA_NODE_CTRL_DST_STATIC;
417 		hw_node->daddr = fchan->cfg.dev_addr;
418 	} else {
419 		hw_node->control |= FDMA_NODE_CTRL_SRC_STATIC;
420 		hw_node->control |= FDMA_NODE_CTRL_DST_INCR;
421 		hw_node->saddr = fchan->cfg.dev_addr;
422 	}
423 
424 	hw_node->generic.sstride = 0;
425 	hw_node->generic.dstride = 0;
426 }
427 
428 static inline struct st_fdma_chan *st_fdma_prep_common(struct dma_chan *chan,
429 		size_t len, enum dma_transfer_direction direction)
430 {
431 	struct st_fdma_chan *fchan;
432 
433 	if (!chan || !len)
434 		return NULL;
435 
436 	fchan = to_st_fdma_chan(chan);
437 
438 	if (!is_slave_direction(direction)) {
439 		dev_err(fchan->fdev->dev, "bad direction?\n");
440 		return NULL;
441 	}
442 
443 	return fchan;
444 }
445 
446 static struct dma_async_tx_descriptor *st_fdma_prep_dma_cyclic(
447 		struct dma_chan *chan, dma_addr_t buf_addr, size_t len,
448 		size_t period_len, enum dma_transfer_direction direction,
449 		unsigned long flags)
450 {
451 	struct st_fdma_chan *fchan;
452 	struct st_fdma_desc *fdesc;
453 	int sg_len, i;
454 
455 	fchan = st_fdma_prep_common(chan, len, direction);
456 	if (!fchan)
457 		return NULL;
458 
459 	if (!period_len)
460 		return NULL;
461 
462 	if (config_reqctrl(fchan, direction)) {
463 		dev_err(fchan->fdev->dev, "bad width or direction\n");
464 		return NULL;
465 	}
466 
467 	/* the buffer length must be a multiple of period_len */
468 	if (len % period_len != 0) {
469 		dev_err(fchan->fdev->dev, "len is not multiple of period\n");
470 		return NULL;
471 	}
472 
473 	sg_len = len / period_len;
474 	fdesc = st_fdma_alloc_desc(fchan, sg_len);
475 	if (!fdesc) {
476 		dev_err(fchan->fdev->dev, "no memory for desc\n");
477 		return NULL;
478 	}
479 
480 	fdesc->iscyclic = true;
481 
482 	for (i = 0; i < sg_len; i++) {
483 		struct st_fdma_hw_node *hw_node = fdesc->node[i].desc;
484 
485 		hw_node->next = fdesc->node[(i + 1) % sg_len].pdesc;
486 
487 		hw_node->control =
488 			FDMA_NODE_CTRL_REQ_MAP_DREQ(fchan->dreq_line);
489 		hw_node->control |= FDMA_NODE_CTRL_INT_EON;
490 
491 		fill_hw_node(hw_node, fchan, direction);
492 
493 		if (direction == DMA_MEM_TO_DEV)
494 			hw_node->saddr = buf_addr + (i * period_len);
495 		else
496 			hw_node->daddr = buf_addr + (i * period_len);
497 
498 		hw_node->nbytes = period_len;
499 		hw_node->generic.length = period_len;
500 	}
501 
502 	return vchan_tx_prep(&fchan->vchan, &fdesc->vdesc, flags);
503 }
504 
505 static struct dma_async_tx_descriptor *st_fdma_prep_slave_sg(
506 		struct dma_chan *chan, struct scatterlist *sgl,
507 		unsigned int sg_len, enum dma_transfer_direction direction,
508 		unsigned long flags, void *context)
509 {
510 	struct st_fdma_chan *fchan;
511 	struct st_fdma_desc *fdesc;
512 	struct st_fdma_hw_node *hw_node;
513 	struct scatterlist *sg;
514 	int i;
515 
516 	fchan = st_fdma_prep_common(chan, sg_len, direction);
517 	if (!fchan)
518 		return NULL;
519 
520 	if (!sgl)
521 		return NULL;
522 
523 	fdesc = st_fdma_alloc_desc(fchan, sg_len);
524 	if (!fdesc) {
525 		dev_err(fchan->fdev->dev, "no memory for desc\n");
526 		return NULL;
527 	}
528 
529 	fdesc->iscyclic = false;
530 
531 	for_each_sg(sgl, sg, sg_len, i) {
532 		hw_node = fdesc->node[i].desc;
533 
534 		hw_node->next = fdesc->node[(i + 1) % sg_len].pdesc;
535 		hw_node->control = FDMA_NODE_CTRL_REQ_MAP_DREQ(fchan->dreq_line);
536 
537 		fill_hw_node(hw_node, fchan, direction);
538 
539 		if (direction == DMA_MEM_TO_DEV)
540 			hw_node->saddr = sg_dma_address(sg);
541 		else
542 			hw_node->daddr = sg_dma_address(sg);
543 
544 		hw_node->nbytes = sg_dma_len(sg);
545 		hw_node->generic.length = sg_dma_len(sg);
546 	}
547 
548 	/* interrupt at end of last node */
549 	hw_node->control |= FDMA_NODE_CTRL_INT_EON;
550 
551 	return vchan_tx_prep(&fchan->vchan, &fdesc->vdesc, flags);
552 }
553 
554 static size_t st_fdma_desc_residue(struct st_fdma_chan *fchan,
555 				   struct virt_dma_desc *vdesc,
556 				   bool in_progress)
557 {
558 	struct st_fdma_desc *fdesc = fchan->fdesc;
559 	size_t residue = 0;
560 	dma_addr_t cur_addr = 0;
561 	int i;
562 
563 	if (in_progress) {
564 		cur_addr = fchan_read(fchan, FDMA_CH_CMD_OFST);
565 		cur_addr &= FDMA_CH_CMD_DATA_MASK;
566 	}
567 
568 	for (i = fchan->fdesc->n_nodes - 1 ; i >= 0; i--) {
569 		if (cur_addr == fdesc->node[i].pdesc) {
570 			residue += fnode_read(fchan, FDMA_CNTN_OFST);
571 			break;
572 		}
573 		residue += fdesc->node[i].desc->nbytes;
574 	}
575 
576 	return residue;
577 }
578 
579 static enum dma_status st_fdma_tx_status(struct dma_chan *chan,
580 					 dma_cookie_t cookie,
581 					 struct dma_tx_state *txstate)
582 {
583 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
584 	struct virt_dma_desc *vd;
585 	enum dma_status ret;
586 	unsigned long flags;
587 
588 	ret = dma_cookie_status(chan, cookie, txstate);
589 	if (ret == DMA_COMPLETE || !txstate)
590 		return ret;
591 
592 	spin_lock_irqsave(&fchan->vchan.lock, flags);
593 	vd = vchan_find_desc(&fchan->vchan, cookie);
594 	if (fchan->fdesc && cookie == fchan->fdesc->vdesc.tx.cookie)
595 		txstate->residue = st_fdma_desc_residue(fchan, vd, true);
596 	else if (vd)
597 		txstate->residue = st_fdma_desc_residue(fchan, vd, false);
598 	else
599 		txstate->residue = 0;
600 
601 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
602 
603 	return ret;
604 }
605 
606 static void st_fdma_issue_pending(struct dma_chan *chan)
607 {
608 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
609 	unsigned long flags;
610 
611 	spin_lock_irqsave(&fchan->vchan.lock, flags);
612 
613 	if (vchan_issue_pending(&fchan->vchan) && !fchan->fdesc)
614 		st_fdma_xfer_desc(fchan);
615 
616 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
617 }
618 
619 static int st_fdma_pause(struct dma_chan *chan)
620 {
621 	unsigned long flags;
622 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
623 	int ch_id = fchan->vchan.chan.chan_id;
624 	unsigned long cmd = FDMA_CMD_PAUSE(ch_id);
625 
626 	dev_dbg(fchan->fdev->dev, "pause chan:%d\n", ch_id);
627 
628 	spin_lock_irqsave(&fchan->vchan.lock, flags);
629 	if (fchan->fdesc)
630 		fdma_write(fchan->fdev, cmd, FDMA_CMD_SET_OFST);
631 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
632 
633 	return 0;
634 }
635 
636 static int st_fdma_resume(struct dma_chan *chan)
637 {
638 	unsigned long flags;
639 	unsigned long val;
640 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
641 	int ch_id = fchan->vchan.chan.chan_id;
642 
643 	dev_dbg(fchan->fdev->dev, "resume chan:%d\n", ch_id);
644 
645 	spin_lock_irqsave(&fchan->vchan.lock, flags);
646 	if (fchan->fdesc) {
647 		val = fchan_read(fchan, FDMA_CH_CMD_OFST);
648 		val &= FDMA_CH_CMD_DATA_MASK;
649 		fchan_write(fchan, val, FDMA_CH_CMD_OFST);
650 	}
651 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
652 
653 	return 0;
654 }
655 
656 static int st_fdma_terminate_all(struct dma_chan *chan)
657 {
658 	unsigned long flags;
659 	LIST_HEAD(head);
660 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
661 	int ch_id = fchan->vchan.chan.chan_id;
662 	unsigned long cmd = FDMA_CMD_PAUSE(ch_id);
663 
664 	dev_dbg(fchan->fdev->dev, "terminate chan:%d\n", ch_id);
665 
666 	spin_lock_irqsave(&fchan->vchan.lock, flags);
667 	fdma_write(fchan->fdev, cmd, FDMA_CMD_SET_OFST);
668 	fchan->fdesc = NULL;
669 	vchan_get_all_descriptors(&fchan->vchan, &head);
670 	spin_unlock_irqrestore(&fchan->vchan.lock, flags);
671 	vchan_dma_desc_free_list(&fchan->vchan, &head);
672 
673 	return 0;
674 }
675 
676 static int st_fdma_slave_config(struct dma_chan *chan,
677 				struct dma_slave_config *slave_cfg)
678 {
679 	struct st_fdma_chan *fchan = to_st_fdma_chan(chan);
680 
681 	memcpy(&fchan->scfg, slave_cfg, sizeof(fchan->scfg));
682 	return 0;
683 }
684 
685 static const struct st_fdma_driverdata fdma_mpe31_stih407_11 = {
686 	.name = "STiH407",
687 	.id = 0,
688 };
689 
690 static const struct st_fdma_driverdata fdma_mpe31_stih407_12 = {
691 	.name = "STiH407",
692 	.id = 1,
693 };
694 
695 static const struct st_fdma_driverdata fdma_mpe31_stih407_13 = {
696 	.name = "STiH407",
697 	.id = 2,
698 };
699 
700 static const struct of_device_id st_fdma_match[] = {
701 	{ .compatible = "st,stih407-fdma-mpe31-11"
702 	  , .data = &fdma_mpe31_stih407_11 },
703 	{ .compatible = "st,stih407-fdma-mpe31-12"
704 	  , .data = &fdma_mpe31_stih407_12 },
705 	{ .compatible = "st,stih407-fdma-mpe31-13"
706 	  , .data = &fdma_mpe31_stih407_13 },
707 	{},
708 };
709 MODULE_DEVICE_TABLE(of, st_fdma_match);
710 
711 static int st_fdma_parse_dt(struct platform_device *pdev,
712 			const struct st_fdma_driverdata *drvdata,
713 			struct st_fdma_dev *fdev)
714 {
715 	snprintf(fdev->fw_name, FW_NAME_SIZE, "fdma_%s_%d.elf",
716 		drvdata->name, drvdata->id);
717 
718 	return of_property_read_u32(pdev->dev.of_node, "dma-channels",
719 				    &fdev->nr_channels);
720 }
721 #define FDMA_DMA_BUSWIDTHS	(BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
722 				 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
723 				 BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
724 				 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
725 
726 static void st_fdma_free(struct st_fdma_dev *fdev)
727 {
728 	struct st_fdma_chan *fchan;
729 	int i;
730 
731 	for (i = 0; i < fdev->nr_channels; i++) {
732 		fchan = &fdev->chans[i];
733 		list_del(&fchan->vchan.chan.device_node);
734 		tasklet_kill(&fchan->vchan.task);
735 	}
736 }
737 
738 static int st_fdma_probe(struct platform_device *pdev)
739 {
740 	struct st_fdma_dev *fdev;
741 	const struct of_device_id *match;
742 	struct device_node *np = pdev->dev.of_node;
743 	const struct st_fdma_driverdata *drvdata;
744 	int ret, i;
745 
746 	match = of_match_device((st_fdma_match), &pdev->dev);
747 	if (!match || !match->data) {
748 		dev_err(&pdev->dev, "No device match found\n");
749 		return -ENODEV;
750 	}
751 
752 	drvdata = match->data;
753 
754 	fdev = devm_kzalloc(&pdev->dev, sizeof(*fdev), GFP_KERNEL);
755 	if (!fdev)
756 		return -ENOMEM;
757 
758 	ret = st_fdma_parse_dt(pdev, drvdata, fdev);
759 	if (ret) {
760 		dev_err(&pdev->dev, "unable to find platform data\n");
761 		goto err;
762 	}
763 
764 	fdev->chans = devm_kcalloc(&pdev->dev, fdev->nr_channels,
765 				   sizeof(struct st_fdma_chan), GFP_KERNEL);
766 	if (!fdev->chans)
767 		return -ENOMEM;
768 
769 	fdev->dev = &pdev->dev;
770 	fdev->drvdata = drvdata;
771 	platform_set_drvdata(pdev, fdev);
772 
773 	fdev->irq = platform_get_irq(pdev, 0);
774 	if (fdev->irq < 0) {
775 		dev_err(&pdev->dev, "Failed to get irq resource\n");
776 		return -EINVAL;
777 	}
778 
779 	ret = devm_request_irq(&pdev->dev, fdev->irq, st_fdma_irq_handler, 0,
780 			       dev_name(&pdev->dev), fdev);
781 	if (ret) {
782 		dev_err(&pdev->dev, "Failed to request irq (%d)\n", ret);
783 		goto err;
784 	}
785 
786 	fdev->slim_rproc = st_slim_rproc_alloc(pdev, fdev->fw_name);
787 	if (IS_ERR(fdev->slim_rproc)) {
788 		ret = PTR_ERR(fdev->slim_rproc);
789 		dev_err(&pdev->dev, "slim_rproc_alloc failed (%d)\n", ret);
790 		goto err;
791 	}
792 
793 	/* Initialise list of FDMA channels */
794 	INIT_LIST_HEAD(&fdev->dma_device.channels);
795 	for (i = 0; i < fdev->nr_channels; i++) {
796 		struct st_fdma_chan *fchan = &fdev->chans[i];
797 
798 		fchan->fdev = fdev;
799 		fchan->vchan.desc_free = st_fdma_free_desc;
800 		vchan_init(&fchan->vchan, &fdev->dma_device);
801 	}
802 
803 	/* Initialise the FDMA dreq (reserve 0 & 31 for FDMA use) */
804 	fdev->dreq_mask = BIT(0) | BIT(31);
805 
806 	dma_cap_set(DMA_SLAVE, fdev->dma_device.cap_mask);
807 	dma_cap_set(DMA_CYCLIC, fdev->dma_device.cap_mask);
808 	dma_cap_set(DMA_MEMCPY, fdev->dma_device.cap_mask);
809 
810 	fdev->dma_device.dev = &pdev->dev;
811 	fdev->dma_device.device_alloc_chan_resources = st_fdma_alloc_chan_res;
812 	fdev->dma_device.device_free_chan_resources = st_fdma_free_chan_res;
813 	fdev->dma_device.device_prep_dma_cyclic	= st_fdma_prep_dma_cyclic;
814 	fdev->dma_device.device_prep_slave_sg = st_fdma_prep_slave_sg;
815 	fdev->dma_device.device_prep_dma_memcpy = st_fdma_prep_dma_memcpy;
816 	fdev->dma_device.device_tx_status = st_fdma_tx_status;
817 	fdev->dma_device.device_issue_pending = st_fdma_issue_pending;
818 	fdev->dma_device.device_terminate_all = st_fdma_terminate_all;
819 	fdev->dma_device.device_config = st_fdma_slave_config;
820 	fdev->dma_device.device_pause = st_fdma_pause;
821 	fdev->dma_device.device_resume = st_fdma_resume;
822 
823 	fdev->dma_device.src_addr_widths = FDMA_DMA_BUSWIDTHS;
824 	fdev->dma_device.dst_addr_widths = FDMA_DMA_BUSWIDTHS;
825 	fdev->dma_device.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
826 	fdev->dma_device.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
827 
828 	ret = dmaenginem_async_device_register(&fdev->dma_device);
829 	if (ret) {
830 		dev_err(&pdev->dev,
831 			"Failed to register DMA device (%d)\n", ret);
832 		goto err_rproc;
833 	}
834 
835 	ret = of_dma_controller_register(np, st_fdma_of_xlate, fdev);
836 	if (ret) {
837 		dev_err(&pdev->dev,
838 			"Failed to register controller (%d)\n", ret);
839 		goto err_rproc;
840 	}
841 
842 	dev_info(&pdev->dev, "ST FDMA engine driver, irq:%d\n", fdev->irq);
843 
844 	return 0;
845 
846 err_rproc:
847 	st_fdma_free(fdev);
848 	st_slim_rproc_put(fdev->slim_rproc);
849 err:
850 	return ret;
851 }
852 
853 static int st_fdma_remove(struct platform_device *pdev)
854 {
855 	struct st_fdma_dev *fdev = platform_get_drvdata(pdev);
856 
857 	devm_free_irq(&pdev->dev, fdev->irq, fdev);
858 	st_slim_rproc_put(fdev->slim_rproc);
859 	of_dma_controller_free(pdev->dev.of_node);
860 
861 	return 0;
862 }
863 
864 static struct platform_driver st_fdma_platform_driver = {
865 	.driver = {
866 		.name = DRIVER_NAME,
867 		.of_match_table = st_fdma_match,
868 	},
869 	.probe = st_fdma_probe,
870 	.remove = st_fdma_remove,
871 };
872 module_platform_driver(st_fdma_platform_driver);
873 
874 MODULE_LICENSE("GPL v2");
875 MODULE_DESCRIPTION("STMicroelectronics FDMA engine driver");
876 MODULE_AUTHOR("Ludovic.barre <Ludovic.barre@st.com>");
877 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
878 MODULE_ALIAS("platform: " DRIVER_NAME);
879