ASoC: amd: acp: Add generic support for PDM controller on ACP

Add driver module for PDM controller on ACP IP block. Expose dai
ops to configure ACP_WOV_PDM_BLOCK registers on ACP. Such dai ops
will be used by platform specific driver module to register dmic
related dai with ASoC.

Signed-off-by: Ajit Kumar Pandey <AjitKumar.Pandey@amd.com>
Link: https://lore.kernel.org/r/20220117115854.455995-2-AjitKumar.Pandey@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/acp/Kconfig

@@ -15,6 +15,9 @@ config SND_SOC_AMD_ACP_COMMON
 
 if SND_SOC_AMD_ACP_COMMON
 
+config SND_SOC_AMD_ACP_PDM
+	tristate
+
 config SND_SOC_AMD_ACP_I2S
 	tristate
 

sound/soc/amd/acp/Makefile

@@ -7,6 +7,7 @@
 #common acp driver
 snd-acp-pcm-objs     := acp-platform.o
 snd-acp-i2s-objs     := acp-i2s.o
+snd-acp-pdm-objs     := acp-pdm.o
 
 #platform specific driver
 snd-acp-renoir-objs     := acp-renoir.o
@@ -18,6 +19,7 @@ snd-acp-sof-mach-objs     := acp-sof-mach.o
 
 obj-$(CONFIG_SND_SOC_AMD_ACP_PCM) += snd-acp-pcm.o
 obj-$(CONFIG_SND_SOC_AMD_ACP_I2S) += snd-acp-i2s.o
+obj-$(CONFIG_SND_SOC_AMD_ACP_PDM) += snd-acp-pdm.o
 
 obj-$(CONFIG_SND_AMD_ASOC_RENOIR) += snd-acp-renoir.o
 

sound/soc/amd/acp/acp-pdm.c

@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
+//
+// This file is provided under a dual BSD/GPLv2 license. When using or
+// redistributing this file, you may do so under either license.
+//
+// Copyright(c) 2022 Advanced Micro Devices, Inc.
+//
+// Authors: Ajit Kumar Pandey <AjitKumar.Pandey@amd.com>
+//	    Vijendar Mukunda <Vijendar.Mukunda@amd.com>
+//
+
+/*
+ * Generic Hardware interface for ACP Audio PDM controller
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+
+#include "amd.h"
+
+#define DRV_NAME "acp-pdm"
+
+#define PDM_DMA_STAT		0x10
+#define PDM_DMA_INTR_MASK	0x10000
+#define PDM_DEC_64		0x2
+#define PDM_CLK_FREQ_MASK	0x07
+#define PDM_MISC_CTRL_MASK	0x10
+#define PDM_ENABLE		0x01
+#define PDM_DISABLE		0x00
+#define DMA_EN_MASK		0x02
+#define DELAY_US		5
+#define PDM_TIMEOUT		1000
+#define ACP_REGION2_OFFSET	0x02000000
+
+static int acp_dmic_prepare(struct snd_pcm_substream *substream,
+			    struct snd_soc_dai *dai)
+{
+	struct acp_stream *stream = substream->runtime->private_data;
+	struct device *dev = dai->component->dev;
+	struct acp_dev_data *adata = dev_get_drvdata(dev);
+	u32 physical_addr, size_dmic, period_bytes;
+	unsigned int dmic_ctrl;
+
+	/* Enable default DMIC clk */
+	writel(PDM_CLK_FREQ_MASK, adata->acp_base + ACP_WOV_CLK_CTRL);
+	dmic_ctrl = readl(adata->acp_base + ACP_WOV_MISC_CTRL);
+	dmic_ctrl |= PDM_MISC_CTRL_MASK;
+	writel(dmic_ctrl, adata->acp_base + ACP_WOV_MISC_CTRL);
+
+	period_bytes = frames_to_bytes(substream->runtime,
+			substream->runtime->period_size);
+	size_dmic = frames_to_bytes(substream->runtime,
+			substream->runtime->buffer_size);
+
+	physical_addr = stream->reg_offset + MEM_WINDOW_START;
+
+	/* Init DMIC Ring buffer */
+	writel(physical_addr, adata->acp_base + ACP_WOV_RX_RINGBUFADDR);
+	writel(size_dmic, adata->acp_base + ACP_WOV_RX_RINGBUFSIZE);
+	writel(period_bytes, adata->acp_base + ACP_WOV_RX_INTR_WATERMARK_SIZE);
+	writel(0x01, adata->acp_base + ACPAXI2AXI_ATU_CTRL);
+
+	return 0;
+}
+
+static int acp_dmic_dai_trigger(struct snd_pcm_substream *substream,
+				int cmd, struct snd_soc_dai *dai)
+{
+	struct device *dev = dai->component->dev;
+	struct acp_dev_data *adata = dev_get_drvdata(dev);
+	unsigned int dma_enable;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		dma_enable = readl(adata->acp_base + ACP_WOV_PDM_DMA_ENABLE);
+		if (!(dma_enable & DMA_EN_MASK)) {
+			writel(PDM_ENABLE, adata->acp_base + ACP_WOV_PDM_ENABLE);
+			writel(PDM_ENABLE, adata->acp_base + ACP_WOV_PDM_DMA_ENABLE);
+		}
+
+		ret = readl_poll_timeout_atomic(adata->acp_base + ACP_WOV_PDM_DMA_ENABLE,
+						dma_enable, (dma_enable & DMA_EN_MASK),
+						DELAY_US, PDM_TIMEOUT);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		dma_enable = readl(adata->acp_base + ACP_WOV_PDM_DMA_ENABLE);
+		if ((dma_enable & DMA_EN_MASK)) {
+			writel(PDM_DISABLE, adata->acp_base + ACP_WOV_PDM_ENABLE);
+			writel(PDM_DISABLE, adata->acp_base + ACP_WOV_PDM_DMA_ENABLE);
+
+		}
+
+		ret = readl_poll_timeout_atomic(adata->acp_base + ACP_WOV_PDM_DMA_ENABLE,
+						dma_enable, !(dma_enable & DMA_EN_MASK),
+						DELAY_US, PDM_TIMEOUT);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static int acp_dmic_hwparams(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *hwparams, struct snd_soc_dai *dai)
+{
+	struct device *dev = dai->component->dev;
+	struct acp_dev_data *adata = dev_get_drvdata(dev);
+	unsigned int channels, ch_mask;
+
+	channels = params_channels(hwparams);
+	switch (channels) {
+	case 2:
+		ch_mask = 0;
+		break;
+	case 4:
+		ch_mask = 1;
+		break;
+	case 6:
+		ch_mask = 2;
+		break;
+	default:
+		dev_err(dev, "Invalid channels %d\n", channels);
+		return -EINVAL;
+	}
+
+	if (params_format(hwparams) != SNDRV_PCM_FORMAT_S32_LE) {
+		dev_err(dai->dev, "Invalid format:%d\n", params_format(hwparams));
+		return -EINVAL;
+	}
+
+	writel(ch_mask, adata->acp_base + ACP_WOV_PDM_NO_OF_CHANNELS);
+	writel(PDM_DEC_64, adata->acp_base + ACP_WOV_PDM_DECIMATION_FACTOR);
+
+	return 0;
+}
+
+static int acp_dmic_dai_startup(struct snd_pcm_substream *substream,
+				struct snd_soc_dai *dai)
+{
+	struct acp_stream *stream = substream->runtime->private_data;
+	struct device *dev = dai->component->dev;
+	struct acp_dev_data *adata = dev_get_drvdata(dev);
+	u32 ext_int_ctrl;
+
+	stream->dai_id = DMIC_INSTANCE;
+	stream->irq_bit = BIT(PDM_DMA_STAT);
+	stream->pte_offset = ACP_SRAM_PDM_PTE_OFFSET;
+	stream->reg_offset = ACP_REGION2_OFFSET;
+
+	/* Enable DMIC Interrupts */
+	ext_int_ctrl = readl(adata->acp_base + ACP_EXTERNAL_INTR_CNTL);
+	ext_int_ctrl |= PDM_DMA_INTR_MASK;
+	writel(ext_int_ctrl, adata->acp_base + ACP_EXTERNAL_INTR_CNTL);
+
+	return 0;
+}
+
+static void acp_dmic_dai_shutdown(struct snd_pcm_substream *substream,
+				  struct snd_soc_dai *dai)
+{
+	struct device *dev = dai->component->dev;
+	struct acp_dev_data *adata = dev_get_drvdata(dev);
+	u32 ext_int_ctrl;
+
+	/* Disable DMIC interrrupts */
+	ext_int_ctrl = readl(adata->acp_base + ACP_EXTERNAL_INTR_CNTL);
+	ext_int_ctrl |= ~PDM_DMA_INTR_MASK;
+	writel(ext_int_ctrl, adata->acp_base + ACP_EXTERNAL_INTR_CNTL);
+}
+
+const struct snd_soc_dai_ops acp_dmic_dai_ops = {
+	.prepare	= acp_dmic_prepare,
+	.hw_params	= acp_dmic_hwparams,
+	.trigger	= acp_dmic_dai_trigger,
+	.startup	= acp_dmic_dai_startup,
+	.shutdown	= acp_dmic_dai_shutdown,
+};
+EXPORT_SYMBOL_NS_GPL(acp_dmic_dai_ops, SND_SOC_ACP_COMMON);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS(DRV_NAME);

sound/soc/amd/acp/amd.h

@@ -17,8 +17,9 @@
 
 #define I2S_SP_INSTANCE			0x00
 #define I2S_BT_INSTANCE			0x01
+#define DMIC_INSTANCE			0x02
 
-#define MEM_WINDOW_START		0x4000000
+#define MEM_WINDOW_START		0x4080000
 
 #define ACP_I2S_REG_START		0x1242400
 #define ACP_I2S_REG_END			0x1242810
@@ -38,6 +39,7 @@
 #define ACP_SRAM_SP_CP_PTE_OFFSET	0x100
 #define ACP_SRAM_BT_PB_PTE_OFFSET	0x200
 #define ACP_SRAM_BT_CP_PTE_OFFSET	0x300
+#define ACP_SRAM_PDM_PTE_OFFSET		0x400
 #define PAGE_SIZE_4K_ENABLE		0x2
 
 #define I2S_SP_TX_MEM_WINDOW_START	0x4000000
@@ -96,6 +98,7 @@ struct acp_dev_data {
 };
 
 extern const struct snd_soc_dai_ops asoc_acp_cpu_dai_ops;
+extern const struct snd_soc_dai_ops acp_dmic_dai_ops;
 
 int asoc_acp_i2s_probe(struct snd_soc_dai *dai);
 int acp_platform_register(struct device *dev);
@@ -131,6 +134,10 @@ static inline u64 acp_get_byte_count(struct acp_dev_data *adata, int dai_id, int
 			high = readl(adata->acp_base + ACP_I2S_RX_LINEARPOSITIONCNTR_HIGH);
 			low = readl(adata->acp_base + ACP_I2S_RX_LINEARPOSITIONCNTR_LOW);
 			break;
+		case DMIC_INSTANCE:
+			high = readl(adata->acp_base + ACP_WOV_RX_LINEARPOSITIONCNTR_HIGH);
+			low = readl(adata->acp_base + ACP_WOV_RX_LINEARPOSITIONCNTR_LOW);
+			break;
 		default:
 			dev_err(adata->dev, "Invalid dai id %x\n", dai_id);
 			return -EINVAL;

sound/soc/amd/acp/chip_offset_byte.h

@@ -73,4 +73,24 @@
 #define ACP_BTTDM_ITER                                0x280C
 #define ACP_BTTDM_TXFRMT                              0x2810
 
+/* Registers from ACP_WOV_PDM block */
+
+#define ACP_WOV_PDM_ENABLE                            0x2C04
+#define ACP_WOV_PDM_DMA_ENABLE                        0x2C08
+#define ACP_WOV_RX_RINGBUFADDR                        0x2C0C
+#define ACP_WOV_RX_RINGBUFSIZE                        0x2C10
+#define ACP_WOV_RX_LINKPOSITIONCNTR                   0x2C14
+#define ACP_WOV_RX_LINEARPOSITIONCNTR_HIGH            0x2C18
+#define ACP_WOV_RX_LINEARPOSITIONCNTR_LOW             0x2C1C
+#define ACP_WOV_RX_INTR_WATERMARK_SIZE                0x2C20
+#define ACP_WOV_PDM_FIFO_FLUSH                        0x2C24
+#define ACP_WOV_PDM_NO_OF_CHANNELS                    0x2C28
+#define ACP_WOV_PDM_DECIMATION_FACTOR                 0x2C2C
+#define ACP_WOV_PDM_VAD_CTRL                          0x2C30
+#define ACP_WOV_BUFFER_STATUS                         0x2C58
+#define ACP_WOV_MISC_CTRL                             0x2C5C
+#define ACP_WOV_CLK_CTRL                              0x2C60
+#define ACP_PDM_VAD_DYNAMIC_CLK_GATING_EN             0x2C64
+#define ACP_WOV_ERROR_STATUS_REGISTER                 0x2C68
+
 #endif