1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * AMD ALSA SoC Yellow Carp PDM Driver
4 *
5 * Copyright 2021 Advanced Micro Devices, Inc.
6 */
7
8#include <linux/platform_device.h>
9#include <linux/module.h>
10#include <linux/bitfield.h>
11#include <linux/err.h>
12#include <linux/io.h>
13#include <sound/pcm_params.h>
14#include <sound/soc.h>
15#include <sound/soc-dai.h>
16#include <linux/pm_runtime.h>
17
18#include "acp6x.h"
19
20#define DRV_NAME "acp_yc_pdm_dma"
21
22static int pdm_gain = 3;
23module_param(pdm_gain, int, 0644);
24MODULE_PARM_DESC(pdm_gain, "Gain control (0-3)");
25
26static const struct snd_pcm_hardware acp6x_pdm_hardware_capture = {
27	.info = SNDRV_PCM_INFO_INTERLEAVED |
28		SNDRV_PCM_INFO_BLOCK_TRANSFER |
29		SNDRV_PCM_INFO_MMAP |
30		SNDRV_PCM_INFO_MMAP_VALID |
31		SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
32	.formats = SNDRV_PCM_FMTBIT_S32_LE,
33	.channels_min = 2,
34	.channels_max = 2,
35	.rates = SNDRV_PCM_RATE_48000,
36	.rate_min = 48000,
37	.rate_max = 48000,
38	.buffer_bytes_max = CAPTURE_MAX_NUM_PERIODS * CAPTURE_MAX_PERIOD_SIZE,
39	.period_bytes_min = CAPTURE_MIN_PERIOD_SIZE,
40	.period_bytes_max = CAPTURE_MAX_PERIOD_SIZE,
41	.periods_min = CAPTURE_MIN_NUM_PERIODS,
42	.periods_max = CAPTURE_MAX_NUM_PERIODS,
43};
44
45static void acp6x_init_pdm_ring_buffer(u32 physical_addr, u32 buffer_size,
46				       u32 watermark_size, void __iomem *acp_base)
47{
48	acp6x_writel(physical_addr, acp_base + ACP_WOV_RX_RINGBUFADDR);
49	acp6x_writel(buffer_size, acp_base + ACP_WOV_RX_RINGBUFSIZE);
50	acp6x_writel(watermark_size, acp_base + ACP_WOV_RX_INTR_WATERMARK_SIZE);
51	acp6x_writel(0x01, acp_base + ACPAXI2AXI_ATU_CTRL);
52}
53
54static void acp6x_enable_pdm_clock(void __iomem *acp_base)
55{
56	u32 pdm_clk_enable, pdm_ctrl;
57
58	pdm_clk_enable = ACP_PDM_CLK_FREQ_MASK;
59	pdm_ctrl = 0x00;
60
61	acp6x_writel(pdm_clk_enable, acp_base + ACP_WOV_CLK_CTRL);
62	pdm_ctrl = acp6x_readl(acp_base + ACP_WOV_MISC_CTRL);
63	pdm_ctrl &= ~ACP_WOV_GAIN_CONTROL;
64	pdm_ctrl |= FIELD_PREP(ACP_WOV_GAIN_CONTROL, clamp(pdm_gain, 0, 3));
65	acp6x_writel(pdm_ctrl, acp_base + ACP_WOV_MISC_CTRL);
66}
67
68static void acp6x_enable_pdm_interrupts(void __iomem *acp_base)
69{
70	u32 ext_int_ctrl;
71
72	ext_int_ctrl = acp6x_readl(acp_base + ACP_EXTERNAL_INTR_CNTL);
73	ext_int_ctrl |= PDM_DMA_INTR_MASK;
74	acp6x_writel(ext_int_ctrl, acp_base + ACP_EXTERNAL_INTR_CNTL);
75}
76
77static void acp6x_disable_pdm_interrupts(void __iomem *acp_base)
78{
79	u32 ext_int_ctrl;
80
81	ext_int_ctrl = acp6x_readl(acp_base + ACP_EXTERNAL_INTR_CNTL);
82	ext_int_ctrl &= ~PDM_DMA_INTR_MASK;
83	acp6x_writel(ext_int_ctrl, acp_base + ACP_EXTERNAL_INTR_CNTL);
84}
85
86static bool acp6x_check_pdm_dma_status(void __iomem *acp_base)
87{
88	bool pdm_dma_status;
89	u32 pdm_enable, pdm_dma_enable;
90
91	pdm_dma_status = false;
92	pdm_enable = acp6x_readl(acp_base + ACP_WOV_PDM_ENABLE);
93	pdm_dma_enable = acp6x_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
94	if ((pdm_enable & ACP_PDM_ENABLE) && (pdm_dma_enable & ACP_PDM_DMA_EN_STATUS))
95		pdm_dma_status = true;
96
97	return pdm_dma_status;
98}
99
100static int acp6x_start_pdm_dma(void __iomem *acp_base)
101{
102	u32 pdm_enable;
103	u32 pdm_dma_enable;
104	int timeout;
105
106	pdm_enable = 0x01;
107	pdm_dma_enable  = 0x01;
108
109	acp6x_enable_pdm_clock(acp_base);
110	acp6x_writel(pdm_enable, acp_base + ACP_WOV_PDM_ENABLE);
111	acp6x_writel(pdm_dma_enable, acp_base + ACP_WOV_PDM_DMA_ENABLE);
112	timeout = 0;
113	while (++timeout < ACP_COUNTER) {
114		pdm_dma_enable = acp6x_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
115		if ((pdm_dma_enable & 0x02) == ACP_PDM_DMA_EN_STATUS)
116			return 0;
117		udelay(DELAY_US);
118	}
119	return -ETIMEDOUT;
120}
121
122static int acp6x_stop_pdm_dma(void __iomem *acp_base)
123{
124	u32 pdm_enable, pdm_dma_enable;
125	int timeout;
126
127	pdm_enable = 0x00;
128	pdm_dma_enable  = 0x00;
129
130	pdm_enable = acp6x_readl(acp_base + ACP_WOV_PDM_ENABLE);
131	pdm_dma_enable = acp6x_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
132	if (pdm_dma_enable & 0x01) {
133		pdm_dma_enable = 0x02;
134		acp6x_writel(pdm_dma_enable, acp_base + ACP_WOV_PDM_DMA_ENABLE);
135		timeout = 0;
136		while (++timeout < ACP_COUNTER) {
137			pdm_dma_enable = acp6x_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
138			if ((pdm_dma_enable & 0x02) == 0x00)
139				break;
140			udelay(DELAY_US);
141		}
142		if (timeout == ACP_COUNTER)
143			return -ETIMEDOUT;
144	}
145	if (pdm_enable == ACP_PDM_ENABLE) {
146		pdm_enable = ACP_PDM_DISABLE;
147		acp6x_writel(pdm_enable, acp_base + ACP_WOV_PDM_ENABLE);
148	}
149	acp6x_writel(0x01, acp_base + ACP_WOV_PDM_FIFO_FLUSH);
150	return 0;
151}
152
153static void acp6x_config_dma(struct pdm_stream_instance *rtd, int direction)
154{
155	u16 page_idx;
156	u32 low, high, val;
157	dma_addr_t addr;
158
159	addr = rtd->dma_addr;
160	val = PDM_PTE_OFFSET;
161
162	/* Group Enable */
163	acp6x_writel(ACP_SRAM_PTE_OFFSET | BIT(31), rtd->acp6x_base +
164		     ACPAXI2AXI_ATU_BASE_ADDR_GRP_1);
165	acp6x_writel(PAGE_SIZE_4K_ENABLE, rtd->acp6x_base +
166		     ACPAXI2AXI_ATU_PAGE_SIZE_GRP_1);
167	for (page_idx = 0; page_idx < rtd->num_pages; page_idx++) {
168		/* Load the low address of page int ACP SRAM through SRBM */
169		low = lower_32_bits(addr);
170		high = upper_32_bits(addr);
171
172		acp6x_writel(low, rtd->acp6x_base + ACP_SCRATCH_REG_0 + val);
173		high |= BIT(31);
174		acp6x_writel(high, rtd->acp6x_base + ACP_SCRATCH_REG_0 + val + 4);
175		val += 8;
176		addr += PAGE_SIZE;
177	}
178}
179
180static int acp6x_pdm_dma_open(struct snd_soc_component *component,
181			      struct snd_pcm_substream *substream)
182{
183	struct snd_pcm_runtime *runtime;
184	struct pdm_dev_data *adata;
185	struct pdm_stream_instance *pdm_data;
186	int ret;
187
188	runtime = substream->runtime;
189	adata = dev_get_drvdata(component->dev);
190	pdm_data = kzalloc(sizeof(*pdm_data), GFP_KERNEL);
191	if (!pdm_data)
192		return -EINVAL;
193
194	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
195		runtime->hw = acp6x_pdm_hardware_capture;
196
197	ret = snd_pcm_hw_constraint_integer(runtime,
198					    SNDRV_PCM_HW_PARAM_PERIODS);
199	if (ret < 0) {
200		dev_err(component->dev, "set integer constraint failed\n");
201		kfree(pdm_data);
202		return ret;
203	}
204
205	acp6x_enable_pdm_interrupts(adata->acp6x_base);
206
207	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
208		adata->capture_stream = substream;
209
210	pdm_data->acp6x_base = adata->acp6x_base;
211	runtime->private_data = pdm_data;
212	return ret;
213}
214
215static int acp6x_pdm_dma_hw_params(struct snd_soc_component *component,
216				   struct snd_pcm_substream *substream,
217				   struct snd_pcm_hw_params *params)
218{
219	struct pdm_stream_instance *rtd;
220	size_t size, period_bytes;
221
222	rtd = substream->runtime->private_data;
223	if (!rtd)
224		return -EINVAL;
225	size = params_buffer_bytes(params);
226	period_bytes = params_period_bytes(params);
227	rtd->dma_addr = substream->runtime->dma_addr;
228	rtd->num_pages = (PAGE_ALIGN(size) >> PAGE_SHIFT);
229	acp6x_config_dma(rtd, substream->stream);
230	acp6x_init_pdm_ring_buffer(PDM_MEM_WINDOW_START, size,
231				   period_bytes, rtd->acp6x_base);
232	return 0;
233}
234
235static u64 acp6x_pdm_get_byte_count(struct pdm_stream_instance *rtd,
236				    int direction)
237{
238	union acp_pdm_dma_count byte_count;
239
240	byte_count.bcount.high =
241			acp6x_readl(rtd->acp6x_base + ACP_WOV_RX_LINEARPOSITIONCNTR_HIGH);
242	byte_count.bcount.low =
243			acp6x_readl(rtd->acp6x_base + ACP_WOV_RX_LINEARPOSITIONCNTR_LOW);
244	return byte_count.bytescount;
245}
246
247static snd_pcm_uframes_t acp6x_pdm_dma_pointer(struct snd_soc_component *comp,
248					       struct snd_pcm_substream *stream)
249{
250	struct pdm_stream_instance *rtd;
251	u32 pos, buffersize;
252	u64 bytescount;
253
254	rtd = stream->runtime->private_data;
255	buffersize = frames_to_bytes(stream->runtime,
256				     stream->runtime->buffer_size);
257	bytescount = acp6x_pdm_get_byte_count(rtd, stream->stream);
258	if (bytescount > rtd->bytescount)
259		bytescount -= rtd->bytescount;
260	pos = do_div(bytescount, buffersize);
261	return bytes_to_frames(stream->runtime, pos);
262}
263
264static int acp6x_pdm_dma_new(struct snd_soc_component *component,
265			     struct snd_soc_pcm_runtime *rtd)
266{
267	struct device *parent = component->dev->parent;
268
269	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
270				       parent, MIN_BUFFER, MAX_BUFFER);
271	return 0;
272}
273
274static int acp6x_pdm_dma_close(struct snd_soc_component *component,
275			       struct snd_pcm_substream *substream)
276{
277	struct pdm_dev_data *adata = dev_get_drvdata(component->dev);
278
279	acp6x_disable_pdm_interrupts(adata->acp6x_base);
280	adata->capture_stream = NULL;
281	return 0;
282}
283
284static int acp6x_pdm_dai_trigger(struct snd_pcm_substream *substream,
285				 int cmd, struct snd_soc_dai *dai)
286{
287	struct pdm_stream_instance *rtd;
288	int ret;
289	bool pdm_status;
290	unsigned int ch_mask;
291
292	rtd = substream->runtime->private_data;
293	ret = 0;
294	switch (substream->runtime->channels) {
295	case TWO_CH:
296		ch_mask = 0x00;
297		break;
298	default:
299		return -EINVAL;
300	}
301	switch (cmd) {
302	case SNDRV_PCM_TRIGGER_START:
303	case SNDRV_PCM_TRIGGER_RESUME:
304	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
305		acp6x_writel(ch_mask, rtd->acp6x_base + ACP_WOV_PDM_NO_OF_CHANNELS);
306		acp6x_writel(PDM_DECIMATION_FACTOR, rtd->acp6x_base +
307			     ACP_WOV_PDM_DECIMATION_FACTOR);
308		rtd->bytescount = acp6x_pdm_get_byte_count(rtd, substream->stream);
309		pdm_status = acp6x_check_pdm_dma_status(rtd->acp6x_base);
310		if (!pdm_status)
311			ret = acp6x_start_pdm_dma(rtd->acp6x_base);
312		break;
313	case SNDRV_PCM_TRIGGER_STOP:
314	case SNDRV_PCM_TRIGGER_SUSPEND:
315	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
316		pdm_status = acp6x_check_pdm_dma_status(rtd->acp6x_base);
317		if (pdm_status)
318			ret = acp6x_stop_pdm_dma(rtd->acp6x_base);
319		break;
320	default:
321		ret = -EINVAL;
322		break;
323	}
324	return ret;
325}
326
327static const struct snd_soc_dai_ops acp6x_pdm_dai_ops = {
328	.trigger   = acp6x_pdm_dai_trigger,
329};
330
331static struct snd_soc_dai_driver acp6x_pdm_dai_driver = {
332	.capture = {
333		.rates = SNDRV_PCM_RATE_48000,
334		.formats = SNDRV_PCM_FMTBIT_S32_LE,
335		.channels_min = 2,
336		.channels_max = 2,
337		.rate_min = 48000,
338		.rate_max = 48000,
339	},
340	.ops = &acp6x_pdm_dai_ops,
341};
342
343static const struct snd_soc_component_driver acp6x_pdm_component = {
344	.name			= DRV_NAME,
345	.open			= acp6x_pdm_dma_open,
346	.close			= acp6x_pdm_dma_close,
347	.hw_params		= acp6x_pdm_dma_hw_params,
348	.pointer		= acp6x_pdm_dma_pointer,
349	.pcm_construct		= acp6x_pdm_dma_new,
350	.legacy_dai_naming	= 1,
351};
352
353static int acp6x_pdm_audio_probe(struct platform_device *pdev)
354{
355	struct resource *res;
356	struct pdm_dev_data *adata;
357	int status;
358
359	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
360	if (!res) {
361		dev_err(&pdev->dev, "IORESOURCE_MEM FAILED\n");
362		return -ENODEV;
363	}
364
365	adata = devm_kzalloc(&pdev->dev, sizeof(*adata), GFP_KERNEL);
366	if (!adata)
367		return -ENOMEM;
368
369	adata->acp6x_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
370	if (!adata->acp6x_base)
371		return -ENOMEM;
372
373	adata->capture_stream = NULL;
374
375	dev_set_drvdata(&pdev->dev, adata);
376	status = devm_snd_soc_register_component(&pdev->dev,
377						 &acp6x_pdm_component,
378						 &acp6x_pdm_dai_driver, 1);
379	if (status) {
380		dev_err(&pdev->dev, "Fail to register acp pdm dai\n");
381
382		return -ENODEV;
383	}
384	pm_runtime_set_autosuspend_delay(&pdev->dev, ACP_SUSPEND_DELAY_MS);
385	pm_runtime_use_autosuspend(&pdev->dev);
386	pm_runtime_mark_last_busy(&pdev->dev);
387	pm_runtime_set_active(&pdev->dev);
388	pm_runtime_enable(&pdev->dev);
389	return 0;
390}
391
392static void acp6x_pdm_audio_remove(struct platform_device *pdev)
393{
394	pm_runtime_disable(&pdev->dev);
395}
396
397static int __maybe_unused acp6x_pdm_resume(struct device *dev)
398{
399	struct pdm_dev_data *adata;
400	struct snd_pcm_runtime *runtime;
401	struct pdm_stream_instance *rtd;
402	u32 period_bytes, buffer_len;
403
404	adata = dev_get_drvdata(dev);
405	if (adata->capture_stream && adata->capture_stream->runtime) {
406		runtime = adata->capture_stream->runtime;
407		rtd = runtime->private_data;
408		period_bytes = frames_to_bytes(runtime, runtime->period_size);
409		buffer_len = frames_to_bytes(runtime, runtime->buffer_size);
410		acp6x_config_dma(rtd, SNDRV_PCM_STREAM_CAPTURE);
411		acp6x_init_pdm_ring_buffer(PDM_MEM_WINDOW_START, buffer_len,
412					   period_bytes, adata->acp6x_base);
413	}
414	acp6x_enable_pdm_interrupts(adata->acp6x_base);
415	return 0;
416}
417
418static int __maybe_unused acp6x_pdm_suspend(struct device *dev)
419{
420	struct pdm_dev_data *adata;
421
422	adata = dev_get_drvdata(dev);
423	acp6x_disable_pdm_interrupts(adata->acp6x_base);
424	return 0;
425}
426
427static int __maybe_unused acp6x_pdm_runtime_resume(struct device *dev)
428{
429	struct pdm_dev_data *adata;
430
431	adata = dev_get_drvdata(dev);
432	acp6x_enable_pdm_interrupts(adata->acp6x_base);
433	return 0;
434}
435
436static const struct dev_pm_ops acp6x_pdm_pm_ops = {
437	SET_RUNTIME_PM_OPS(acp6x_pdm_suspend, acp6x_pdm_runtime_resume, NULL)
438	SET_SYSTEM_SLEEP_PM_OPS(acp6x_pdm_suspend, acp6x_pdm_resume)
439};
440
441static struct platform_driver acp6x_pdm_dma_driver = {
442	.probe = acp6x_pdm_audio_probe,
443	.remove_new = acp6x_pdm_audio_remove,
444	.driver = {
445		.name = "acp_yc_pdm_dma",
446		.pm = &acp6x_pdm_pm_ops,
447	},
448};
449
450module_platform_driver(acp6x_pdm_dma_driver);
451
452MODULE_AUTHOR("Vijendar.Mukunda@amd.com");
453MODULE_DESCRIPTION("AMD ACP6x YC PDM Driver");
454MODULE_LICENSE("GPL v2");
455MODULE_ALIAS("platform:" DRV_NAME);
456