chip/mt_scp: support audio codec WoV

BRANCH=none
BUG=b:122027734, b:123268236
TEST=1. define CONFIG_AUDIO_CODEC in board.h
2. define CONFIG_AUDIO_CODEC_DMIC in board.h
3. define CONFIG_AUDIO_CODEC_DMIC_SOFTWARE_GAIN in board.h
4. define CONFIG_AUDIO_CODEC_DMIC_MAX_SOFTWARE_GAIN in board.h
5. define CONFIG_AUDIO_CODEC_WOV in board.h
6. make BOARD=kukui_scp -j

Change-Id: I51e22947c3f535c9a504033c502ec2ff1c688e6a
Signed-off-by: Tzung-Bi Shih <tzungbi@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1490801
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>

3 files changed, 141 insertions, 0 deletions

diff --git a/chip/mt_scp/audio_codec_wov.c b/chip/mt_scp/audio_codec_wov.c
new file mode 100644
index 0000000000..bff8f776b7
--- /dev/null
+++ b/chip/mt_scp/audio_codec_wov.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright 2019 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "audio_codec.h"
+#include "hooks.h"
+#include "memmap.h"
+#include "registers.h"
+#include "task.h"
+#include "util.h"
+
+/* VIF FIFO irq is triggered above this level */
+#define WOV_TRIGGER_LEVEL 160
+
+int audio_codec_wov_enable_notifier(void)
+{
+	SCP_VIF_FIFO_DATA_THRE = WOV_TRIGGER_LEVEL + 1;
+	SCP_VIF_FIFO_EN |= VIF_FIFO_IRQ_EN;
+
+	task_enable_irq(SCP_IRQ_MAD_FIFO);
+
+	return EC_SUCCESS;
+}
+
+int audio_codec_wov_disable_notifier(void)
+{
+	SCP_VIF_FIFO_EN &= ~VIF_FIFO_IRQ_EN;
+
+	task_disable_irq(SCP_IRQ_MAD_FIFO);
+
+	return EC_SUCCESS;
+}
+
+int audio_codec_wov_enable(void)
+{
+	SCP_VIF_FIFO_EN = 0;
+
+	SCP_RXIF_CFG0 = (RXIF_CFG0_RESET_VAL & ~RXIF_RGDL2_MASK) |
+			RXIF_RGDL2_DMIC_16K;
+	SCP_RXIF_CFG1 = RXIF_CFG1_RESET_VAL;
+
+	SCP_VIF_FIFO_EN |= VIF_FIFO_RSTN;
+
+	return EC_SUCCESS;
+}
+
+int audio_codec_wov_disable(void)
+{
+	SCP_VIF_FIFO_EN = 0;
+
+	return EC_SUCCESS;
+}
+
+static size_t wov_fifo_level(void)
+{
+	uint32_t fifo_status = SCP_VIF_FIFO_STATUS;
+
+	if (!(fifo_status & VIF_FIFO_VALID))
+		return 0;
+
+	if (fifo_status & VIF_FIFO_FULL)
+		return VIF_FIFO_MAX;
+
+	return VIF_FIFO_LEVEL(fifo_status);
+}
+
+int32_t audio_codec_wov_read(void *buf, uint32_t count)
+{
+	int16_t *out = buf;
+
+	count >>= 1;
+
+	while (count-- && wov_fifo_level())
+		*out++ = SCP_VIF_FIFO_DATA;
+
+	return (void *)out - buf;
+}
+
+static void wov_fifo_interrupt_handler(void)
+{
+#ifdef HAS_TASK_WOV
+	task_wake(TASK_ID_WOV);
+#endif
+
+	audio_codec_wov_disable_notifier();
+
+	/* Read to clear */
+	SCP_VIF_FIFO_IRQ_STATUS;
+}
+DECLARE_IRQ(SCP_IRQ_MAD_FIFO, wov_fifo_interrupt_handler, 2);
+
+int audio_codec_memmap_ap_to_ec(uintptr_t ap_addr, uintptr_t *ec_addr)
+{
+	return memmap_ap_to_scp(ap_addr, ec_addr);
+}
diff --git a/chip/mt_scp/build.mk b/chip/mt_scp/build.mk
index 151876a1c8..fa6164056e 100644
--- a/chip/mt_scp/build.mk
+++ b/chip/mt_scp/build.mk
@@ -26,6 +26,7 @@ endif
 endif
 
 # Optional chip modules
+chip-$(CONFIG_AUDIO_CODEC_WOV)+=audio_codec_wov.o
 chip-$(CONFIG_COMMON_TIMER)+=hrtimer.o
 chip-$(CONFIG_I2C)+=i2c.o
 chip-$(CONFIG_IPI)+=ipi.o ipi_table.o
diff --git a/chip/mt_scp/registers.h b/chip/mt_scp/registers.h
index dd70d6b273..6196a936e2 100644
--- a/chip/mt_scp/registers.h
+++ b/chip/mt_scp/registers.h
@@ -187,6 +187,49 @@
 #define SCP_L1_EXT_ADDR_OTHER_LSB_MASK	(BIT(SCP_REMAP_ADDR_SHIFT) - 1)
 #define SCP_L1_EXT_ADDR_OTHER_MSB_MASK	((~0) << SCP_REMAP_ADDR_SHIFT)
 
+/* Audio/voice FIFO */
+#define SCP_AUDIO_BASE			(SCP_CFG_BASE + 0x1000)
+#define SCP_VIF_FIFO_EN			REG32(SCP_AUDIO_BASE)
+#define   VIF_FIFO_RSTN			(1 << 0)
+#define   VIF_FIFO_IRQ_EN		(1 << 1)
+#define   VIF_FIFO_SRAM_PWR		(1 << 2)
+#define   VIF_FIFO_RSTN_STATUS		(1 << 4)
+#define SCP_VIF_FIFO_STATUS		REG32(SCP_AUDIO_BASE + 0x04)
+#define   VIF_FIFO_VALID		(1 << 0)
+#define   VIF_FIFO_FULL			(1 << 4)
+#define   VIF_FIFO_LEVEL(status)	(((status) >> 16) & 0xff)
+#define   VIF_FIFO_MAX			256
+#define SCP_VIF_FIFO_DATA		REG32(SCP_AUDIO_BASE + 0x08)
+#define SCP_VIF_FIFO_DATA_THRE		REG32(SCP_AUDIO_BASE + 0x0C)
+/* VIF IRQ status clears on read! */
+#define SCP_VIF_FIFO_IRQ_STATUS		REG32(SCP_AUDIO_BASE + 0x10)
+/* Audio/voice serial interface */
+#define SCP_RXIF_CFG0			REG32(SCP_AUDIO_BASE + 0x14)
+#define   RXIF_CFG0_RESET_VAL		0x2A130001
+#define   RXIF_AFE_ON			(1 << 0)
+#define   RXIF_SCKINV			(1 << 1)
+#define   RXIF_RG_DL_2_IN_MODE(mode)	(((mode) & 0xf) << 8)
+#define   RXIF_RGDL2_AMIC_16K		(0x1 << 8)
+#define   RXIF_RGDL2_DMIC_16K		(0x2 << 8)
+#define   RXIF_RGDL2_DMIC_LP_16K	(0x3 << 8)
+#define   RXIF_RGDL2_AMIC_32K		(0x5 << 8)
+#define   RXIF_RGDL2_MASK		(0xf << 8)
+#define   RXIF_UP8X_RSP(p)		(((p) & 0x7) << 16)
+#define   RXIF_RG_RX_READEN		(1 << 19)
+#define   RXIF_MONO			(1 << 20)
+#define   RXIF_RG_CLK_A16P7K_EN(cnt)	(((cnt) & 0xff) << 24)
+#define SCP_RXIF_CFG1			REG32(SCP_AUDIO_BASE + 0x18)
+#define   RXIF_CFG1_RESET_VAL		0x33180014
+#define   RXIF_RG_SYNC_CNT_TBL(t)	((t) & 0x1ff)
+#define   RXIF_RG_SYNC_SEARCH_TBL(t)	(((t) & 0x1f) << 16)
+#define   RXIF_RG_SYNC_CHECK_ROUND(r)	(((r) & 0xf) << 24)
+#define   RXIF_RG_INSYNC_CHECK_ROUND(r)	(((r) & 0xf) << 28)
+#define SCP_RXIF_CFG2			REG32(SCP_AUDIO_BASE + 0x1C)
+#define   RXIF_SYNC_WORD(w)		((w) & 0xffff)
+#define SCP_RXIF_OUT			REG32(SCP_AUDIO_BASE + 0x20)
+#define SCP_RXIF_STATUS			REG32(SCP_AUDIO_BASE + 0x24)
+#define SCP_RXIF_IRQ_EN			REG32(SCP_AUDIO_BASE + 0x28)
+
 /* INTC control */
 #define SCP_INTC_BASE			(SCP_CFG_BASE + 0x2000)
 #define SCP_INTC_IRQ_STATUS		REG32(SCP_INTC_BASE)