1/*
2 * Renesas R-Car Audio DMAC support
3 *
4 * Copyright (C) 2015 Renesas Electronics Corp.
5 * Copyright (c) 2015 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/delay.h>
12#include <linux/of_dma.h>
13#include "rsnd.h"
14
15/*
16 * Audio DMAC peri peri register
17 */
18#define PDMASAR		0x00
19#define PDMADAR		0x04
20#define PDMACHCR	0x0c
21
22/* PDMACHCR */
23#define PDMACHCR_DE		(1 << 0)
24
25struct rsnd_dma_ctrl {
26	void __iomem *base;
27	int dmapp_num;
28};
29
30#define rsnd_priv_to_dmac(p)	((struct rsnd_dma_ctrl *)(p)->dma)
31
32/*
33 *		Audio DMAC
34 */
35static void rsnd_dmaen_complete(void *data)
36{
37	struct rsnd_dma *dma = (struct rsnd_dma *)data;
38	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
39	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
40
41	/*
42	 * Renesas sound Gen1 needs 1 DMAC,
43	 * Gen2 needs 2 DMAC.
44	 * In Gen2 case, it are Audio-DMAC, and Audio-DMAC-peri-peri.
45	 * But, Audio-DMAC-peri-peri doesn't have interrupt,
46	 * and this driver is assuming that here.
47	 *
48	 * If Audio-DMAC-peri-peri has interrpt,
49	 * rsnd_dai_pointer_update() will be called twice,
50	 * ant it will breaks io->byte_pos
51	 */
52
53	rsnd_dai_pointer_update(io, io->byte_per_period);
54}
55
56static void rsnd_dmaen_stop(struct rsnd_dma *dma)
57{
58	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
59
60	dmaengine_terminate_all(dmaen->chan);
61}
62
63static void rsnd_dmaen_start(struct rsnd_dma *dma)
64{
65	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
66	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
67	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
68	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
69	struct snd_pcm_substream *substream = io->substream;
70	struct device *dev = rsnd_priv_to_dev(priv);
71	struct dma_async_tx_descriptor *desc;
72	int is_play = rsnd_io_is_play(io);
73
74	desc = dmaengine_prep_dma_cyclic(dmaen->chan,
75					 substream->runtime->dma_addr,
76					 snd_pcm_lib_buffer_bytes(substream),
77					 snd_pcm_lib_period_bytes(substream),
78					 is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
79					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
80
81	if (!desc) {
82		dev_err(dev, "dmaengine_prep_slave_sg() fail\n");
83		return;
84	}
85
86	desc->callback		= rsnd_dmaen_complete;
87	desc->callback_param	= dma;
88
89	if (dmaengine_submit(desc) < 0) {
90		dev_err(dev, "dmaengine_submit() fail\n");
91		return;
92	}
93
94	dma_async_issue_pending(dmaen->chan);
95}
96
97struct dma_chan *rsnd_dma_request_channel(struct device_node *of_node,
98					  struct rsnd_mod *mod, char *name)
99{
100	struct dma_chan *chan;
101	struct device_node *np;
102	int i = 0;
103
104	for_each_child_of_node(of_node, np) {
105		if (i == rsnd_mod_id(mod))
106			break;
107		i++;
108	}
109
110	chan = of_dma_request_slave_channel(np, name);
111
112	of_node_put(np);
113	of_node_put(of_node);
114
115	return chan;
116}
117
118static struct dma_chan *rsnd_dmaen_request_channel(struct rsnd_mod *mod_from,
119						   struct rsnd_mod *mod_to)
120{
121	if ((!mod_from && !mod_to) ||
122	    (mod_from && mod_to))
123		return NULL;
124
125	if (mod_from)
126		return rsnd_mod_dma_req(mod_from);
127	else
128		return rsnd_mod_dma_req(mod_to);
129}
130
131static int rsnd_dmaen_init(struct rsnd_priv *priv, struct rsnd_dma *dma, int id,
132			   struct rsnd_mod *mod_from, struct rsnd_mod *mod_to)
133{
134	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
135	struct device *dev = rsnd_priv_to_dev(priv);
136	struct dma_slave_config cfg = {};
137	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
138	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
139	int is_play = rsnd_io_is_play(io);
140	int ret;
141
142	if (dmaen->chan) {
143		dev_err(dev, "it already has dma channel\n");
144		return -EIO;
145	}
146
147	if (dev->of_node) {
148		dmaen->chan = rsnd_dmaen_request_channel(mod_from, mod_to);
149	} else {
150		dma_cap_mask_t mask;
151
152		dma_cap_zero(mask);
153		dma_cap_set(DMA_SLAVE, mask);
154
155		dmaen->chan = dma_request_channel(mask, shdma_chan_filter,
156						  (void *)id);
157	}
158	if (IS_ERR_OR_NULL(dmaen->chan)) {
159		dmaen->chan = NULL;
160		dev_err(dev, "can't get dma channel\n");
161		goto rsnd_dma_channel_err;
162	}
163
164	cfg.direction	= is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
165	cfg.src_addr	= dma->src_addr;
166	cfg.dst_addr	= dma->dst_addr;
167	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
168	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
169
170	dev_dbg(dev, "dma : %pad -> %pad\n",
171		&cfg.src_addr, &cfg.dst_addr);
172
173	ret = dmaengine_slave_config(dmaen->chan, &cfg);
174	if (ret < 0)
175		goto rsnd_dma_init_err;
176
177	return 0;
178
179rsnd_dma_init_err:
180	rsnd_dma_quit(dma);
181rsnd_dma_channel_err:
182
183	/*
184	 * DMA failed. try to PIO mode
185	 * see
186	 *	rsnd_ssi_fallback()
187	 *	rsnd_rdai_continuance_probe()
188	 */
189	return -EAGAIN;
190}
191
192static void rsnd_dmaen_quit(struct rsnd_dma *dma)
193{
194	struct rsnd_dmaen *dmaen = rsnd_dma_to_dmaen(dma);
195
196	if (dmaen->chan)
197		dma_release_channel(dmaen->chan);
198
199	dmaen->chan = NULL;
200}
201
202static struct rsnd_dma_ops rsnd_dmaen_ops = {
203	.start	= rsnd_dmaen_start,
204	.stop	= rsnd_dmaen_stop,
205	.init	= rsnd_dmaen_init,
206	.quit	= rsnd_dmaen_quit,
207};
208
209/*
210 *		Audio DMAC peri peri
211 */
212static const u8 gen2_id_table_ssiu[] = {
213	0x00, /* SSI00 */
214	0x04, /* SSI10 */
215	0x08, /* SSI20 */
216	0x0c, /* SSI3  */
217	0x0d, /* SSI4  */
218	0x0e, /* SSI5  */
219	0x0f, /* SSI6  */
220	0x10, /* SSI7  */
221	0x11, /* SSI8  */
222	0x12, /* SSI90 */
223};
224static const u8 gen2_id_table_scu[] = {
225	0x2d, /* SCU_SRCI0 */
226	0x2e, /* SCU_SRCI1 */
227	0x2f, /* SCU_SRCI2 */
228	0x30, /* SCU_SRCI3 */
229	0x31, /* SCU_SRCI4 */
230	0x32, /* SCU_SRCI5 */
231	0x33, /* SCU_SRCI6 */
232	0x34, /* SCU_SRCI7 */
233	0x35, /* SCU_SRCI8 */
234	0x36, /* SCU_SRCI9 */
235};
236static const u8 gen2_id_table_cmd[] = {
237	0x37, /* SCU_CMD0 */
238	0x38, /* SCU_CMD1 */
239};
240
241static u32 rsnd_dmapp_get_id(struct rsnd_mod *mod)
242{
243	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
244	struct rsnd_mod *ssi = rsnd_io_to_mod_ssi(io);
245	struct rsnd_mod *src = rsnd_io_to_mod_src(io);
246	struct rsnd_mod *dvc = rsnd_io_to_mod_dvc(io);
247	const u8 *entry = NULL;
248	int id = rsnd_mod_id(mod);
249	int size = 0;
250
251	if (mod == ssi) {
252		entry = gen2_id_table_ssiu;
253		size = ARRAY_SIZE(gen2_id_table_ssiu);
254	} else if (mod == src) {
255		entry = gen2_id_table_scu;
256		size = ARRAY_SIZE(gen2_id_table_scu);
257	} else if (mod == dvc) {
258		entry = gen2_id_table_cmd;
259		size = ARRAY_SIZE(gen2_id_table_cmd);
260	}
261
262	if (!entry)
263		return 0xFF;
264
265	if (size <= id)
266		return 0xFF;
267
268	return entry[id];
269}
270
271static u32 rsnd_dmapp_get_chcr(struct rsnd_mod *mod_from,
272			       struct rsnd_mod *mod_to)
273{
274	return	(rsnd_dmapp_get_id(mod_from) << 24) +
275		(rsnd_dmapp_get_id(mod_to) << 16);
276}
277
278#define rsnd_dmapp_addr(dmac, dma, reg) \
279	(dmac->base + 0x20 + reg + \
280	 (0x10 * rsnd_dma_to_dmapp(dma)->dmapp_id))
281static void rsnd_dmapp_write(struct rsnd_dma *dma, u32 data, u32 reg)
282{
283	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
284	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
285	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
286	struct device *dev = rsnd_priv_to_dev(priv);
287
288	dev_dbg(dev, "w %p : %08x\n", rsnd_dmapp_addr(dmac, dma, reg), data);
289
290	iowrite32(data, rsnd_dmapp_addr(dmac, dma, reg));
291}
292
293static u32 rsnd_dmapp_read(struct rsnd_dma *dma, u32 reg)
294{
295	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
296	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
297	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
298
299	return ioread32(rsnd_dmapp_addr(dmac, dma, reg));
300}
301
302static void rsnd_dmapp_stop(struct rsnd_dma *dma)
303{
304	int i;
305
306	rsnd_dmapp_write(dma, 0, PDMACHCR);
307
308	for (i = 0; i < 1024; i++) {
309		if (0 == rsnd_dmapp_read(dma, PDMACHCR))
310			return;
311		udelay(1);
312	}
313}
314
315static void rsnd_dmapp_start(struct rsnd_dma *dma)
316{
317	struct rsnd_dmapp *dmapp = rsnd_dma_to_dmapp(dma);
318
319	rsnd_dmapp_write(dma, dma->src_addr,	PDMASAR);
320	rsnd_dmapp_write(dma, dma->dst_addr,	PDMADAR);
321	rsnd_dmapp_write(dma, dmapp->chcr,	PDMACHCR);
322}
323
324static int rsnd_dmapp_init(struct rsnd_priv *priv, struct rsnd_dma *dma, int id,
325			   struct rsnd_mod *mod_from, struct rsnd_mod *mod_to)
326{
327	struct rsnd_dmapp *dmapp = rsnd_dma_to_dmapp(dma);
328	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
329	struct device *dev = rsnd_priv_to_dev(priv);
330
331	dmapp->dmapp_id = dmac->dmapp_num;
332	dmapp->chcr = rsnd_dmapp_get_chcr(mod_from, mod_to) | PDMACHCR_DE;
333
334	dmac->dmapp_num++;
335
336	rsnd_dmapp_stop(dma);
337
338	dev_dbg(dev, "id/src/dst/chcr = %d/%pad/%pad/%08x\n",
339		dmapp->dmapp_id, &dma->src_addr, &dma->dst_addr, dmapp->chcr);
340
341	return 0;
342}
343
344static struct rsnd_dma_ops rsnd_dmapp_ops = {
345	.start	= rsnd_dmapp_start,
346	.stop	= rsnd_dmapp_stop,
347	.init	= rsnd_dmapp_init,
348	.quit	= rsnd_dmapp_stop,
349};
350
351/*
352 *		Common DMAC Interface
353 */
354
355/*
356 *	DMA read/write register offset
357 *
358 *	RSND_xxx_I_N	for Audio DMAC input
359 *	RSND_xxx_O_N	for Audio DMAC output
360 *	RSND_xxx_I_P	for Audio DMAC peri peri input
361 *	RSND_xxx_O_P	for Audio DMAC peri peri output
362 *
363 *	ex) R-Car H2 case
364 *	      mod        / DMAC in    / DMAC out   / DMAC PP in / DMAC pp out
365 *	SSI : 0xec541000 / 0xec241008 / 0xec24100c
366 *	SSIU: 0xec541000 / 0xec100000 / 0xec100000 / 0xec400000 / 0xec400000
367 *	SCU : 0xec500000 / 0xec000000 / 0xec004000 / 0xec300000 / 0xec304000
368 *	CMD : 0xec500000 /            / 0xec008000                0xec308000
369 */
370#define RDMA_SSI_I_N(addr, i)	(addr ##_reg - 0x00300000 + (0x40 * i) + 0x8)
371#define RDMA_SSI_O_N(addr, i)	(addr ##_reg - 0x00300000 + (0x40 * i) + 0xc)
372
373#define RDMA_SSIU_I_N(addr, i)	(addr ##_reg - 0x00441000 + (0x1000 * i))
374#define RDMA_SSIU_O_N(addr, i)	(addr ##_reg - 0x00441000 + (0x1000 * i))
375
376#define RDMA_SSIU_I_P(addr, i)	(addr ##_reg - 0x00141000 + (0x1000 * i))
377#define RDMA_SSIU_O_P(addr, i)	(addr ##_reg - 0x00141000 + (0x1000 * i))
378
379#define RDMA_SRC_I_N(addr, i)	(addr ##_reg - 0x00500000 + (0x400 * i))
380#define RDMA_SRC_O_N(addr, i)	(addr ##_reg - 0x004fc000 + (0x400 * i))
381
382#define RDMA_SRC_I_P(addr, i)	(addr ##_reg - 0x00200000 + (0x400 * i))
383#define RDMA_SRC_O_P(addr, i)	(addr ##_reg - 0x001fc000 + (0x400 * i))
384
385#define RDMA_CMD_O_N(addr, i)	(addr ##_reg - 0x004f8000 + (0x400 * i))
386#define RDMA_CMD_O_P(addr, i)	(addr ##_reg - 0x001f8000 + (0x400 * i))
387
388static dma_addr_t
389rsnd_gen2_dma_addr(struct rsnd_priv *priv,
390		   struct rsnd_mod *mod,
391		   int is_play, int is_from)
392{
393	struct device *dev = rsnd_priv_to_dev(priv);
394	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
395	phys_addr_t ssi_reg = rsnd_gen_get_phy_addr(priv, RSND_GEN2_SSI);
396	phys_addr_t src_reg = rsnd_gen_get_phy_addr(priv, RSND_GEN2_SCU);
397	int is_ssi = !!(rsnd_io_to_mod_ssi(io) == mod);
398	int use_src = !!rsnd_io_to_mod_src(io);
399	int use_dvc = !!rsnd_io_to_mod_dvc(io);
400	int id = rsnd_mod_id(mod);
401	struct dma_addr {
402		dma_addr_t out_addr;
403		dma_addr_t in_addr;
404	} dma_addrs[3][2][3] = {
405		/* SRC */
406		{{{ 0,				0 },
407		  /* Capture */
408		  { RDMA_SRC_O_N(src, id),	RDMA_SRC_I_P(src, id) },
409		  { RDMA_CMD_O_N(src, id),	RDMA_SRC_I_P(src, id) } },
410		 /* Playback */
411		 {{ 0,				0, },
412		  { RDMA_SRC_O_P(src, id),	RDMA_SRC_I_N(src, id) },
413		  { RDMA_CMD_O_P(src, id),	RDMA_SRC_I_N(src, id) } }
414		},
415		/* SSI */
416		/* Capture */
417		{{{ RDMA_SSI_O_N(ssi, id),	0 },
418		  { RDMA_SSIU_O_P(ssi, id),	0 },
419		  { RDMA_SSIU_O_P(ssi, id),	0 } },
420		 /* Playback */
421		 {{ 0,				RDMA_SSI_I_N(ssi, id) },
422		  { 0,				RDMA_SSIU_I_P(ssi, id) },
423		  { 0,				RDMA_SSIU_I_P(ssi, id) } }
424		},
425		/* SSIU */
426		/* Capture */
427		{{{ RDMA_SSIU_O_N(ssi, id),	0 },
428		  { RDMA_SSIU_O_P(ssi, id),	0 },
429		  { RDMA_SSIU_O_P(ssi, id),	0 } },
430		 /* Playback */
431		 {{ 0,				RDMA_SSIU_I_N(ssi, id) },
432		  { 0,				RDMA_SSIU_I_P(ssi, id) },
433		  { 0,				RDMA_SSIU_I_P(ssi, id) } } },
434	};
435
436	/* it shouldn't happen */
437	if (use_dvc && !use_src)
438		dev_err(dev, "DVC is selected without SRC\n");
439
440	/* use SSIU or SSI ? */
441	if (is_ssi && rsnd_ssi_use_busif(mod))
442		is_ssi++;
443
444	return (is_from) ?
445		dma_addrs[is_ssi][is_play][use_src + use_dvc].out_addr :
446		dma_addrs[is_ssi][is_play][use_src + use_dvc].in_addr;
447}
448
449static dma_addr_t rsnd_dma_addr(struct rsnd_priv *priv,
450				struct rsnd_mod *mod,
451				int is_play, int is_from)
452{
453	/*
454	 * gen1 uses default DMA addr
455	 */
456	if (rsnd_is_gen1(priv))
457		return 0;
458
459	if (!mod)
460		return 0;
461
462	return rsnd_gen2_dma_addr(priv, mod, is_play, is_from);
463}
464
465#define MOD_MAX 4 /* MEM/SSI/SRC/DVC */
466static void rsnd_dma_of_path(struct rsnd_dma *dma,
467			     int is_play,
468			     struct rsnd_mod **mod_from,
469			     struct rsnd_mod **mod_to)
470{
471	struct rsnd_mod *this = rsnd_dma_to_mod(dma);
472	struct rsnd_dai_stream *io = rsnd_mod_to_io(this);
473	struct rsnd_mod *ssi = rsnd_io_to_mod_ssi(io);
474	struct rsnd_mod *src = rsnd_io_to_mod_src(io);
475	struct rsnd_mod *dvc = rsnd_io_to_mod_dvc(io);
476	struct rsnd_mod *mod[MOD_MAX];
477	int i, index;
478
479
480	for (i = 0; i < MOD_MAX; i++)
481		mod[i] = NULL;
482
483	/*
484	 * in play case...
485	 *
486	 * src -> dst
487	 *
488	 * mem -> SSI
489	 * mem -> SRC -> SSI
490	 * mem -> SRC -> DVC -> SSI
491	 */
492	mod[0] = NULL; /* for "mem" */
493	index = 1;
494	for (i = 1; i < MOD_MAX; i++) {
495		if (!src) {
496			mod[i] = ssi;
497		} else if (!dvc) {
498			mod[i] = src;
499			src = NULL;
500		} else {
501			if ((!is_play) && (this == src))
502				this = dvc;
503
504			mod[i] = (is_play) ? src : dvc;
505			i++;
506			mod[i] = (is_play) ? dvc : src;
507			src = NULL;
508			dvc = NULL;
509		}
510
511		if (mod[i] == this)
512			index = i;
513
514		if (mod[i] == ssi)
515			break;
516	}
517
518	if (is_play) {
519		*mod_from = mod[index - 1];
520		*mod_to   = mod[index];
521	} else {
522		*mod_from = mod[index];
523		*mod_to   = mod[index - 1];
524	}
525}
526
527void rsnd_dma_stop(struct rsnd_dma *dma)
528{
529	dma->ops->stop(dma);
530}
531
532void rsnd_dma_start(struct rsnd_dma *dma)
533{
534	dma->ops->start(dma);
535}
536
537void rsnd_dma_quit(struct rsnd_dma *dma)
538{
539	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
540	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
541	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
542
543	if (!dmac)
544		return;
545
546	dma->ops->quit(dma);
547}
548
549int rsnd_dma_init(struct rsnd_priv *priv, struct rsnd_dma *dma, int id)
550{
551	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
552	struct rsnd_mod *mod_from;
553	struct rsnd_mod *mod_to;
554	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
555	struct rsnd_dma_ctrl *dmac = rsnd_priv_to_dmac(priv);
556	int is_play = rsnd_io_is_play(io);
557
558	/*
559	 * DMA failed. try to PIO mode
560	 * see
561	 *	rsnd_ssi_fallback()
562	 *	rsnd_rdai_continuance_probe()
563	 */
564	if (!dmac)
565		return -EAGAIN;
566
567	rsnd_dma_of_path(dma, is_play, &mod_from, &mod_to);
568
569	dma->src_addr = rsnd_dma_addr(priv, mod_from, is_play, 1);
570	dma->dst_addr = rsnd_dma_addr(priv, mod_to,   is_play, 0);
571
572	/* for Gen2 */
573	if (mod_from && mod_to)
574		dma->ops = &rsnd_dmapp_ops;
575	else
576		dma->ops = &rsnd_dmaen_ops;
577
578	/* for Gen1, overwrite */
579	if (rsnd_is_gen1(priv))
580		dma->ops = &rsnd_dmaen_ops;
581
582	return dma->ops->init(priv, dma, id, mod_from, mod_to);
583}
584
585int rsnd_dma_probe(struct platform_device *pdev,
586		   const struct rsnd_of_data *of_data,
587		   struct rsnd_priv *priv)
588{
589	struct device *dev = rsnd_priv_to_dev(priv);
590	struct rsnd_dma_ctrl *dmac;
591	struct resource *res;
592
593	/*
594	 * for Gen1
595	 */
596	if (rsnd_is_gen1(priv))
597		return 0;
598
599	/*
600	 * for Gen2
601	 */
602	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "audmapp");
603	dmac = devm_kzalloc(dev, sizeof(*dmac), GFP_KERNEL);
604	if (!dmac || !res) {
605		dev_err(dev, "dma allocate failed\n");
606		return 0; /* it will be PIO mode */
607	}
608
609	dmac->dmapp_num = 0;
610	dmac->base = devm_ioremap_resource(dev, res);
611	if (IS_ERR(dmac->base))
612		return PTR_ERR(dmac->base);
613
614	priv->dma = dmac;
615
616	return 0;
617}
618