ASoC: amd: add acp3x pdm driver dma ops

This patch adds PDM driver DMA operations.

Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200518171704.24999-8-Vijendar.Mukunda@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/renoir/acp3x-pdm-dma.c

@@ -16,6 +16,25 @@
 
 #define DRV_NAME "acp_rn_pdm_dma"
 
+static const struct snd_pcm_hardware acp_pdm_hardware_capture = {
+	.info = SNDRV_PCM_INFO_INTERLEAVED |
+		SNDRV_PCM_INFO_BLOCK_TRANSFER |
+		SNDRV_PCM_INFO_MMAP |
+		SNDRV_PCM_INFO_MMAP_VALID |
+		SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
+	.formats = SNDRV_PCM_FMTBIT_S32_LE,
+	.channels_min = 2,
+	.channels_max = 2,
+	.rates = SNDRV_PCM_RATE_48000,
+	.rate_min = 48000,
+	.rate_max = 48000,
+	.buffer_bytes_max = CAPTURE_MAX_NUM_PERIODS * CAPTURE_MAX_PERIOD_SIZE,
+	.period_bytes_min = CAPTURE_MIN_PERIOD_SIZE,
+	.period_bytes_max = CAPTURE_MAX_PERIOD_SIZE,
+	.periods_min = CAPTURE_MIN_NUM_PERIODS,
+	.periods_max = CAPTURE_MAX_NUM_PERIODS,
+};
+
 static irqreturn_t pdm_irq_handler(int irq, void *dev_id)
 {
 	struct pdm_dev_data *rn_pdm_data;
@@ -41,6 +60,176 @@ static irqreturn_t pdm_irq_handler(int irq, void *dev_id)
 		return IRQ_NONE;
 }
 
+static void init_pdm_ring_buffer(u32 physical_addr,
+				 u32 buffer_size,
+				 u32 watermark_size,
+				 void __iomem *acp_base)
+{
+	rn_writel(physical_addr, acp_base + ACP_WOV_RX_RINGBUFADDR);
+	rn_writel(buffer_size, acp_base + ACP_WOV_RX_RINGBUFSIZE);
+	rn_writel(watermark_size, acp_base + ACP_WOV_RX_INTR_WATERMARK_SIZE);
+	rn_writel(0x01, acp_base + ACPAXI2AXI_ATU_CTRL);
+}
+
+static void enable_pdm_interrupts(void __iomem *acp_base)
+{
+	u32 ext_int_ctrl;
+
+	ext_int_ctrl = rn_readl(acp_base + ACP_EXTERNAL_INTR_CNTL);
+	ext_int_ctrl |= PDM_DMA_INTR_MASK;
+	rn_writel(ext_int_ctrl, acp_base + ACP_EXTERNAL_INTR_CNTL);
+}
+
+static void disable_pdm_interrupts(void __iomem *acp_base)
+{
+	u32 ext_int_ctrl;
+
+	ext_int_ctrl = rn_readl(acp_base + ACP_EXTERNAL_INTR_CNTL);
+	ext_int_ctrl |= ~PDM_DMA_INTR_MASK;
+	rn_writel(ext_int_ctrl, acp_base + ACP_EXTERNAL_INTR_CNTL);
+}
+
+static void config_acp_dma(struct pdm_stream_instance *rtd, int direction)
+{
+	u16 page_idx;
+	u32 low, high, val;
+	dma_addr_t addr;
+
+	addr = rtd->dma_addr;
+	val = 0;
+
+	/* Group Enable */
+	rn_writel(ACP_SRAM_PTE_OFFSET | BIT(31), rtd->acp_base +
+		  ACPAXI2AXI_ATU_BASE_ADDR_GRP_1);
+	rn_writel(PAGE_SIZE_4K_ENABLE, rtd->acp_base +
+		  ACPAXI2AXI_ATU_PAGE_SIZE_GRP_1);
+
+	for (page_idx = 0; page_idx < rtd->num_pages; page_idx++) {
+		/* Load the low address of page int ACP SRAM through SRBM */
+		low = lower_32_bits(addr);
+		high = upper_32_bits(addr);
+
+		rn_writel(low, rtd->acp_base + ACP_SCRATCH_REG_0 + val);
+		high |= BIT(31);
+		rn_writel(high, rtd->acp_base + ACP_SCRATCH_REG_0 + val + 4);
+		val += 8;
+		addr += PAGE_SIZE;
+	}
+}
+
+static int acp_pdm_dma_open(struct snd_soc_component *component,
+			    struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime;
+	struct pdm_dev_data *adata;
+	struct pdm_stream_instance *pdm_data;
+	int ret;
+
+	runtime = substream->runtime;
+	adata = dev_get_drvdata(component->dev);
+	pdm_data = kzalloc(sizeof(*pdm_data), GFP_KERNEL);
+	if (!pdm_data)
+		return -EINVAL;
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		runtime->hw = acp_pdm_hardware_capture;
+
+	ret = snd_pcm_hw_constraint_integer(runtime,
+					    SNDRV_PCM_HW_PARAM_PERIODS);
+	if (ret < 0) {
+		dev_err(component->dev, "set integer constraint failed\n");
+		kfree(pdm_data);
+		return ret;
+	}
+
+	enable_pdm_interrupts(adata->acp_base);
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		adata->capture_stream = substream;
+
+	pdm_data->acp_base = adata->acp_base;
+	runtime->private_data = pdm_data;
+	return ret;
+}
+
+static int acp_pdm_dma_hw_params(struct snd_soc_component *component,
+				 struct snd_pcm_substream *substream,
+				 struct snd_pcm_hw_params *params)
+{
+	struct pdm_stream_instance *rtd;
+	size_t size, period_bytes;
+
+	rtd = substream->runtime->private_data;
+	if (!rtd)
+		return -EINVAL;
+	size = params_buffer_bytes(params);
+	period_bytes = params_period_bytes(params);
+	rtd->dma_addr = substream->dma_buffer.addr;
+	rtd->num_pages = (PAGE_ALIGN(size) >> PAGE_SHIFT);
+	config_acp_dma(rtd, substream->stream);
+	init_pdm_ring_buffer(MEM_WINDOW_START, size, period_bytes,
+			     rtd->acp_base);
+	return 0;
+}
+
+static u64 acp_pdm_get_byte_count(struct pdm_stream_instance *rtd,
+				  int direction)
+{
+	union acp_pdm_dma_count byte_count;
+
+	byte_count.bcount.high =
+			rn_readl(rtd->acp_base +
+				 ACP_WOV_RX_LINEARPOSITIONCNTR_HIGH);
+	byte_count.bcount.low =
+			rn_readl(rtd->acp_base +
+				 ACP_WOV_RX_LINEARPOSITIONCNTR_LOW);
+	return byte_count.bytescount;
+}
+
+static snd_pcm_uframes_t acp_pdm_dma_pointer(struct snd_soc_component *comp,
+					     struct snd_pcm_substream *stream)
+{
+	struct pdm_stream_instance *rtd;
+	u32 pos, buffersize;
+	u64 bytescount;
+
+	rtd = stream->runtime->private_data;
+	buffersize = frames_to_bytes(stream->runtime,
+				     stream->runtime->buffer_size);
+	bytescount = acp_pdm_get_byte_count(rtd, stream->stream);
+	if (bytescount > rtd->bytescount)
+		bytescount -= rtd->bytescount;
+	pos = do_div(bytescount, buffersize);
+	return bytes_to_frames(stream->runtime, pos);
+}
+
+static int acp_pdm_dma_new(struct snd_soc_component *component,
+			   struct snd_soc_pcm_runtime *rtd)
+{
+	struct device *parent = component->dev->parent;
+
+	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
+				       parent, MIN_BUFFER, MAX_BUFFER);
+	return 0;
+}
+
+static int acp_pdm_dma_mmap(struct snd_soc_component *component,
+			    struct snd_pcm_substream *substream,
+			    struct vm_area_struct *vma)
+{
+	return snd_pcm_lib_default_mmap(substream, vma);
+}
+
+static int acp_pdm_dma_close(struct snd_soc_component *component,
+			     struct snd_pcm_substream *substream)
+{
+	struct pdm_dev_data *adata = dev_get_drvdata(component->dev);
+
+	disable_pdm_interrupts(adata->acp_base);
+	adata->capture_stream = NULL;
+	return 0;
+}
+
 static struct snd_soc_dai_driver acp_pdm_dai_driver = {
 	.capture = {
 		.rates = SNDRV_PCM_RATE_48000,
@@ -55,6 +244,12 @@ static struct snd_soc_dai_driver acp_pdm_dai_driver = {
 
 static const struct snd_soc_component_driver acp_pdm_component = {
 	.name		= DRV_NAME,
+	.open		= acp_pdm_dma_open,
+	.close		= acp_pdm_dma_close,
+	.hw_params	= acp_pdm_dma_hw_params,
+	.pointer	= acp_pdm_dma_pointer,
+	.mmap		= acp_pdm_dma_mmap,
+	.pcm_construct	= acp_pdm_dma_new,
 };
 
 static int acp_pdm_audio_probe(struct platform_device *pdev)

sound/soc/amd/renoir/rn_acp3x.h

@@ -29,13 +29,42 @@
 #define ACP_ERROR_MASK 0x20000000
 #define ACP_EXT_INTR_STAT_CLEAR_MASK 0xFFFFFFFF
 #define PDM_DMA_STAT 0x10
+#define PDM_DMA_INTR_MASK  0x10000
+#define ACP_ERROR_STAT 29
 
+#define ACP_SRAM_PTE_OFFSET	0x02050000
+#define PAGE_SIZE_4K_ENABLE     0x2
+#define MEM_WINDOW_START	0x4000000
+
+#define CAPTURE_MIN_NUM_PERIODS     4
+#define CAPTURE_MAX_NUM_PERIODS     4
+#define CAPTURE_MAX_PERIOD_SIZE     8192
+#define CAPTURE_MIN_PERIOD_SIZE     4096
+
+#define MAX_BUFFER (CAPTURE_MAX_PERIOD_SIZE * CAPTURE_MAX_NUM_PERIODS)
+#define MIN_BUFFER MAX_BUFFER
 struct pdm_dev_data {
 	u32 pdm_irq;
 	void __iomem *acp_base;
 	struct snd_pcm_substream *capture_stream;
 };
 
+struct pdm_stream_instance {
+	u16 num_pages;
+	u16 channels;
+	dma_addr_t dma_addr;
+	u64 bytescount;
+	void __iomem *acp_base;
+};
+
+union acp_pdm_dma_count {
+	struct {
+	u32 low;
+	u32 high;
+	} bcount;
+	u64 bytescount;
+};
+
 static inline u32 rn_readl(void __iomem *base_addr)
 {
 	return readl(base_addr - ACP_PHY_BASE_ADDRESS);