summaryrefslogtreecommitdiffstats
path: root/sound/soc/loongson/loongson_dma.c
blob: 65b6719e61c56dbd577f84f919c65064bdabb4b7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
// SPDX-License-Identifier: GPL-2.0
//
// Loongson ALSA SoC Platform (DMA) driver
//
// Copyright (C) 2023 Loongson Technology Corporation Limited
// Author: Yingkun Meng <mengyingkun@loongson.cn>
//

#include <linux/module.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/delay.h>
#include <linux/pm_runtime.h>
#include <linux/dma-mapping.h>
#include <sound/soc.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include "loongson_i2s.h"

/* DMA dma_order Register */
#define DMA_ORDER_STOP          (1 << 4) /* DMA stop */
#define DMA_ORDER_START         (1 << 3) /* DMA start */
#define DMA_ORDER_ASK_VALID     (1 << 2) /* DMA ask valid flag */
#define DMA_ORDER_AXI_UNCO      (1 << 1) /* Uncache access */
#define DMA_ORDER_ADDR_64       (1 << 0) /* 64bits address support */

#define DMA_ORDER_ASK_MASK      (~0x1fUL) /* Ask addr mask */
#define DMA_ORDER_CTRL_MASK     (0x0fUL)  /* Control mask  */

/*
 * DMA registers descriptor.
 */
struct loongson_dma_desc {
	u32 order;		/* Next descriptor address register */
	u32 saddr;		/* Source address register */
	u32 daddr;		/* Device address register */
	u32 length;		/* Total length register */
	u32 step_length;	/* Memory stride register */
	u32 step_times;		/* Repeat time register */
	u32 cmd;		/* Command register */
	u32 stats;		/* Status register */
	u32 order_hi;		/* Next descriptor high address register */
	u32 saddr_hi;		/* High source address register */
	u32 res[6];		/* Reserved */
} __packed;

struct loongson_runtime_data {
	struct loongson_dma_data *dma_data;

	struct loongson_dma_desc *dma_desc_arr;
	dma_addr_t dma_desc_arr_phy;
	int dma_desc_arr_size;

	struct loongson_dma_desc *dma_pos_desc;
	dma_addr_t dma_pos_desc_phy;
};

static const struct snd_pcm_hardware ls_pcm_hardware = {
	.info = SNDRV_PCM_INFO_MMAP |
		SNDRV_PCM_INFO_INTERLEAVED |
		SNDRV_PCM_INFO_MMAP_VALID |
		SNDRV_PCM_INFO_RESUME |
		SNDRV_PCM_INFO_PAUSE,
	.formats = (SNDRV_PCM_FMTBIT_S8 |
		SNDRV_PCM_FMTBIT_S16_LE |
		SNDRV_PCM_FMTBIT_S20_3LE |
		SNDRV_PCM_FMTBIT_S24_LE),
	.period_bytes_min = 128,
	.period_bytes_max = 128 * 1024,
	.periods_min = 1,
	.periods_max = PAGE_SIZE / sizeof(struct loongson_dma_desc),
	.buffer_bytes_max = 1024 * 1024,
};

static struct
loongson_dma_desc *dma_desc_save(struct loongson_runtime_data *prtd)
{
	void __iomem *order_reg = prtd->dma_data->order_addr;
	u64 val;

	val = (u64)prtd->dma_pos_desc_phy & DMA_ORDER_ASK_MASK;
	val |= (readq(order_reg) & DMA_ORDER_CTRL_MASK);
	val |= DMA_ORDER_ASK_VALID;
	writeq(val, order_reg);

	while (readl(order_reg) & DMA_ORDER_ASK_VALID)
		udelay(2);

	return prtd->dma_pos_desc;
}

static int loongson_pcm_trigger(struct snd_soc_component *component,
				struct snd_pcm_substream *substream, int cmd)
{
	struct loongson_runtime_data *prtd = substream->runtime->private_data;
	struct device *dev = substream->pcm->card->dev;
	void __iomem *order_reg = prtd->dma_data->order_addr;
	u64 val;
	int ret = 0;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		val = prtd->dma_pos_desc_phy & DMA_ORDER_ASK_MASK;
		if (dev->coherent_dma_mask == DMA_BIT_MASK(64))
			val |= DMA_ORDER_ADDR_64;
		else
			val &= ~DMA_ORDER_ADDR_64;
		val |= (readq(order_reg) & DMA_ORDER_CTRL_MASK);
		val |= DMA_ORDER_START;
		writeq(val, order_reg);

		while ((readl(order_reg) & DMA_ORDER_START))
			udelay(2);
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		dma_desc_save(prtd);

		/* dma stop */
		val = readq(order_reg) | DMA_ORDER_STOP;
		writeq(val, order_reg);
		udelay(1000);

		break;
	default:
		dev_err(dev, "Invalid pcm trigger operation\n");
		return -EINVAL;
	}

	return ret;
}

static int loongson_pcm_hw_params(struct snd_soc_component *component,
				  struct snd_pcm_substream *substream,
				  struct snd_pcm_hw_params *params)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct device *dev = substream->pcm->card->dev;
	struct loongson_runtime_data *prtd = runtime->private_data;
	size_t buf_len = params_buffer_bytes(params);
	size_t period_len = params_period_bytes(params);
	dma_addr_t order_addr, mem_addr;
	struct loongson_dma_desc *desc;
	u32 num_periods;
	int i;

	if (buf_len % period_len) {
		dev_err(dev, "buf len not multiply of period len\n");
		return -EINVAL;
	}

	num_periods = buf_len / period_len;
	if (!num_periods || num_periods > prtd->dma_desc_arr_size) {
		dev_err(dev, "dma data too small or too big\n");
		return -EINVAL;
	}

	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
	runtime->dma_bytes = buf_len;

	/* initialize dma descriptor array */
	mem_addr = runtime->dma_addr;
	order_addr = prtd->dma_desc_arr_phy;
	for (i = 0; i < num_periods; i++) {
		desc = &prtd->dma_desc_arr[i];

		/* next descriptor physical address */
		order_addr += sizeof(*desc);
		desc->order = lower_32_bits(order_addr | BIT(0));
		desc->order_hi = upper_32_bits(order_addr);

		desc->saddr = lower_32_bits(mem_addr);
		desc->saddr_hi = upper_32_bits(mem_addr);
		desc->daddr = prtd->dma_data->dev_addr;

		desc->cmd = BIT(0);
		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
			desc->cmd |= BIT(12);

		desc->length = period_len >> 2;
		desc->step_length = 0;
		desc->step_times = 1;

		mem_addr += period_len;
	}
	desc = &prtd->dma_desc_arr[num_periods - 1];
	desc->order = lower_32_bits(prtd->dma_desc_arr_phy | BIT(0));
	desc->order_hi = upper_32_bits(prtd->dma_desc_arr_phy);

	/* init position descriptor */
	*prtd->dma_pos_desc = *prtd->dma_desc_arr;

	return 0;
}

static snd_pcm_uframes_t
loongson_pcm_pointer(struct snd_soc_component *component,
		     struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct loongson_runtime_data *prtd = runtime->private_data;
	struct loongson_dma_desc *desc;
	snd_pcm_uframes_t x;
	u64 addr;

	desc = dma_desc_save(prtd);
	addr = ((u64)desc->saddr_hi << 32) | desc->saddr;

	x = bytes_to_frames(runtime, addr - runtime->dma_addr);
	if (x == runtime->buffer_size)
		x = 0;
	return x;
}

static irqreturn_t loongson_pcm_dma_irq(int irq, void *devid)
{
	struct snd_pcm_substream *substream = devid;

	snd_pcm_period_elapsed(substream);
	return IRQ_HANDLED;
}

static int loongson_pcm_open(struct snd_soc_component *component,
			     struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_card *card = substream->pcm->card;
	struct loongson_runtime_data *prtd;
	struct loongson_dma_data *dma_data;
	int ret;

	/*
	 * For mysterious reasons (and despite what the manual says)
	 * playback samples are lost if the DMA count is not a multiple
	 * of the DMA burst size.  Let's add a rule to enforce that.
	 */
	snd_pcm_hw_constraint_step(runtime, 0,
				   SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 128);
	snd_pcm_hw_constraint_step(runtime, 0,
				   SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 128);
	snd_pcm_hw_constraint_integer(substream->runtime,
				      SNDRV_PCM_HW_PARAM_PERIODS);
	snd_soc_set_runtime_hwparams(substream, &ls_pcm_hardware);

	prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
	if (!prtd)
		return -ENOMEM;

	prtd->dma_desc_arr = dma_alloc_coherent(card->dev, PAGE_SIZE,
						&prtd->dma_desc_arr_phy,
						GFP_KERNEL);
	if (!prtd->dma_desc_arr) {
		ret = -ENOMEM;
		goto desc_err;
	}
	prtd->dma_desc_arr_size = PAGE_SIZE / sizeof(*prtd->dma_desc_arr);

	prtd->dma_pos_desc = dma_alloc_coherent(card->dev,
						sizeof(*prtd->dma_pos_desc),
						&prtd->dma_pos_desc_phy,
						GFP_KERNEL);
	if (!prtd->dma_pos_desc) {
		ret = -ENOMEM;
		goto pos_err;
	}

	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
	prtd->dma_data = dma_data;

	substream->runtime->private_data = prtd;

	return 0;
pos_err:
	dma_free_coherent(card->dev, PAGE_SIZE, prtd->dma_desc_arr,
			  prtd->dma_desc_arr_phy);
desc_err:
	kfree(prtd);

	return ret;
}

static int loongson_pcm_close(struct snd_soc_component *component,
			      struct snd_pcm_substream *substream)
{
	struct snd_card *card = substream->pcm->card;
	struct loongson_runtime_data *prtd = substream->runtime->private_data;

	dma_free_coherent(card->dev, PAGE_SIZE, prtd->dma_desc_arr,
			  prtd->dma_desc_arr_phy);

	dma_free_coherent(card->dev, sizeof(*prtd->dma_pos_desc),
			  prtd->dma_pos_desc, prtd->dma_pos_desc_phy);

	kfree(prtd);
	return 0;
}

static int loongson_pcm_mmap(struct snd_soc_component *component,
			     struct snd_pcm_substream *substream,
			     struct vm_area_struct *vma)
{
	return remap_pfn_range(vma, vma->vm_start,
			substream->dma_buffer.addr >> PAGE_SHIFT,
			vma->vm_end - vma->vm_start, vma->vm_page_prot);
}

static int loongson_pcm_new(struct snd_soc_component *component,
			    struct snd_soc_pcm_runtime *rtd)
{
	struct snd_card *card = rtd->card->snd_card;
	struct snd_pcm_substream *substream;
	struct loongson_dma_data *dma_data;
	unsigned int i;
	int ret;

	for_each_pcm_streams(i) {
		substream = rtd->pcm->streams[i].substream;
		if (!substream)
			continue;

		dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0),
						    substream);
		ret = devm_request_irq(card->dev, dma_data->irq,
				       loongson_pcm_dma_irq,
				       IRQF_TRIGGER_HIGH, LS_I2S_DRVNAME,
				       substream);
		if (ret < 0) {
			dev_err(card->dev, "request irq for DMA failed\n");
			return ret;
		}
	}

	return snd_pcm_set_fixed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
					    card->dev,
					    ls_pcm_hardware.buffer_bytes_max);
}

const struct snd_soc_component_driver loongson_i2s_component = {
	.name		= LS_I2S_DRVNAME,
	.open		= loongson_pcm_open,
	.close		= loongson_pcm_close,
	.hw_params	= loongson_pcm_hw_params,
	.trigger	= loongson_pcm_trigger,
	.pointer	= loongson_pcm_pointer,
	.mmap		= loongson_pcm_mmap,
	.pcm_construct	= loongson_pcm_new,
};