mb/google/zork: Generate I2SM ACPI device at runtime

This change moves the generation of I2SM ACPI device from static asl
file to runtime generation by ACP device driver. dmic_select_gpio is
set to match version 3+ of Trembyle and Dalboz schematics. In order to
maintain backward compatibility, dmic_select_gpio is updated at
runtime using variant_audio_update for board versions that are prior
to version 3 of reference schematics.

The only difference from static generation is that the device I2SM is
added under ACPD (i.e. ACP device) instead of CREC (Chrome EC
device). It does not make any functional difference from the kernel
perspective.

BUG=b:157603026
TEST=Verified that the following device gets generated in SSDT:
    Scope (\_SB.PCI0.PBRA.ACPD)
    {
        Device (I2SM)
        {
            Name (_HID, "AMDI5682")  // _HID: Hardware ID
            Name (_UID, One)  // _UID: Unique ID
            Name (_DDN, "I2S machine driver")  // _DDN: DOS Device Name
            Method (_STA, 0, NotSerialized)  // _STA: Status
            {
                Return (0x0F)
            }

            Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
            {
                GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly,
                    "\\_SB.GPIO", 0x00, ResourceConsumer, ,
                    )
                    {   // Pin list
                        0x000D
                    }
            })
            Name (_DSD, Package (0x02)  // _DSD: Device-Specific Data
            {
                ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301") /* Device Properties for _DSD */,
                Package (0x01)
                {
                    Package (0x02)
                    {
                        "dmic-gpios",
                        Package (0x04)
                        {
                            \_SB.PCI0.PBRA.ACPD.I2SM,
                            Zero,
                            Zero,
                            Zero
                        }
                    }
                }
            })
        }
    }
Verified audio via speakers and mic input.

Signed-off-by: Furquan Shaikh <furquan@google.com>
Change-Id: I5d1602c7f719eef9487ddea68e429d27408f9a76
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/coreboot/+/2253638
Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Tested-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/42971
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

6 files changed, 42 insertions, 41 deletions

diff --git a/src/mainboard/google/zork/mainboard.c b/src/mainboard/google/zork/mainboard.c
index 283f0e0841..f295271596 100644
--- a/src/mainboard/google/zork/mainboard.c
+++ b/src/mainboard/google/zork/mainboard.c
@@ -132,6 +132,12 @@ static void mainboard_configure_gpios(void)
 					  override_num_gpios);
 }
 
+static void mainboard_devtree_update(void)
+{
+	variant_audio_update();
+	variant_devtree_update();
+}
+
 static void mainboard_init(void *chip_info)
 {
 	const struct sci_source *gpes;
@@ -145,7 +151,7 @@ static void mainboard_init(void *chip_info)
 	mainboard_configure_gpios();
 
 	/* Update DUT configuration */
-	variant_devtree_update();
+	mainboard_devtree_update();
 
 	/*
 	 * Some platforms use SCI not generated by a GPIO pin (event above 23).
diff --git a/src/mainboard/google/zork/variants/baseboard/Makefile.inc b/src/mainboard/google/zork/variants/baseboard/Makefile.inc
index c09fc7ebb7..2b0ee3cbd8 100644
--- a/src/mainboard/google/zork/variants/baseboard/Makefile.inc
+++ b/src/mainboard/google/zork/variants/baseboard/Makefile.inc
@@ -23,6 +23,7 @@ ramstage-$(CONFIG_BOARD_GOOGLE_BASEBOARD_DALBOZ) += gpio_baseboard_dalboz.c
 ramstage-$(CONFIG_BOARD_GOOGLE_BASEBOARD_DALBOZ) += fsps_baseboard_dalboz.c
 ramstage-y += helpers.c
 ramstage-y += tpm_tis.c
+ramstage-y += ramstage_common.c
 
 smm-$(CONFIG_BOARD_GOOGLE_BASEBOARD_TREMBYLE) += gpio_baseboard_trembyle.c
 smm-$(CONFIG_BOARD_GOOGLE_BASEBOARD_DALBOZ) += gpio_baseboard_dalboz.c
diff --git a/src/mainboard/google/zork/variants/baseboard/devicetree.cb b/src/mainboard/google/zork/variants/baseboard/devicetree.cb
index 3cc311b171..93247492ed 100644
--- a/src/mainboard/google/zork/variants/baseboard/devicetree.cb
+++ b/src/mainboard/google/zork/variants/baseboard/devicetree.cb
@@ -16,6 +16,16 @@ chip soc/amd/picasso
 
 	register "acp_pin_cfg" = "I2S_PINS_I2S_TDM"
 
+	# DMIC select GPIO for ACP machine device
+	# This GPIO is used to select DMIC0 or DMIC1 by the kernel driver. It does not
+	# really have a polarity since low and high control the selection of DMIC and
+	# hence does not have an active polarity.
+	# Kernel driver does not use the polarity field and instead treats the GPIO
+	# selection as follows:
+	# Set low (0) = Select DMIC0
+	# Set high (1) = Select DMIC1
+	register "dmic_select_gpio" = "ACPI_GPIO_OUTPUT(GPIO_67)"
+
 	# Start : OPN Performance Configuration
 	# (Configuratin that is common for all variants)
 	# For the below fields, 0 indicates use SOC default
diff --git a/src/mainboard/google/zork/variants/baseboard/include/baseboard/acpi/audio.asl b/src/mainboard/google/zork/variants/baseboard/include/baseboard/acpi/audio.asl
index ae5663e7c7..b892570a7f 100644
--- a/src/mainboard/google/zork/variants/baseboard/include/baseboard/acpi/audio.asl
+++ b/src/mainboard/google/zork/variants/baseboard/include/baseboard/acpi/audio.asl
@@ -3,43 +3,3 @@
 Scope (EC0.CREC) {
 	#include <ec/google/chromeec/acpi/codec.asl>
 }
-
-/* machine driver */
-Device (I2SM)
-{
-	Name (_HID, "AMDI5682")
-	Name (_UID, 1)
-	Name (_DDN, "I2S machine Driver")
-
-	Name (_CRS, ResourceTemplate ()
-	{
-#if CONFIG(BOARD_GOOGLE_BASEBOARD_DALBOZ)
-		/* DMIC select GPIO */
-		GpioIo (Exclusive, PullDefault, 0x0000, 0x0000,
-			IoRestrictionNone, "\\_SB.GPIO", 0x00,
-			ResourceConsumer,,) { 6 }
-#else
-		/* DMIC select GPIO */
-		GpioIo (Exclusive, PullDefault, 0x0000, 0x0000,
-			IoRestrictionNone, "\\_SB.GPIO", 0x00,
-			ResourceConsumer,,) { 13 }
-#endif
-	})
-	/* Device-Specific Data */
-	Name (_DSD, Package ()
-	{
-		ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
-		Package ()
-		{
-			Package ()
-			{
-				"dmic-gpio", Package () { ^I2SM, 0, 0, 0 }
-			}
-		}
-
-	})
-	Method (_STA)
-	{
-		Return (0xF)
-	}
-}
diff --git a/src/mainboard/google/zork/variants/baseboard/include/baseboard/variants.h b/src/mainboard/google/zork/variants/baseboard/include/baseboard/variants.h
index 6c5b95b5cc..c3986bcbf8 100644
--- a/src/mainboard/google/zork/variants/baseboard/include/baseboard/variants.h
+++ b/src/mainboard/google/zork/variants/baseboard/include/baseboard/variants.h
@@ -35,6 +35,8 @@ const struct soc_amd_gpio *variant_sleep_gpio_table(size_t *size, int slp_typ);
 void variant_romstage_entry(void);
 /* Modify devictree settings during ramstage. */
 void variant_devtree_update(void);
+/* Update audio configuration in devicetree during ramstage. */
+void variant_audio_update(void);
 /* Configure PCIe power and reset lines as per variant sequencing requirements. */
 void variant_pcie_power_reset_configure(void);
 
diff --git a/src/mainboard/google/zork/variants/baseboard/ramstage_common.c b/src/mainboard/google/zork/variants/baseboard/ramstage_common.c
new file mode 100644
index 0000000000..6372af6a88
--- /dev/null
+++ b/src/mainboard/google/zork/variants/baseboard/ramstage_common.c
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <acpi/acpi_device.h>
+#include <baseboard/variants.h>
+#include <ec/google/chromeec/ec.h>
+#include <soc/gpio.h>
+
+void variant_audio_update(void)
+{
+	struct soc_amd_picasso_config *cfg = config_of_soc();
+	uint32_t board_version;
+	struct acpi_gpio *gpio = &cfg->dmic_select_gpio;
+
+	if (!google_chromeec_cbi_get_board_version(&board_version) &&
+	    (board_version >= CONFIG_VARIANT_MIN_BOARD_ID_V3_SCHEMATICS))
+		return;
+
+	if (CONFIG(BOARD_GOOGLE_BASEBOARD_TREMBYLE))
+		gpio->pins[0] = GPIO_13;
+	else
+		gpio->pins[0] = GPIO_6;
+}