soc/amd/common/acp: Populate _WOV ACPI method

In order to support Audio Co-processor (ACP) DMIC hardware runtime
detection on the platform, ACPI _WOV method is populated on the
concerned ACP device. This method returns the ACPI Integer value as 1
if ACP DMIC exists on the platform.

BUG=b:182960979
TEST=Build and boot to OS in guybrush. Ensure that the _WOV ACPI method
is populated under the scope of ACP device.
    Scope (\_SB.PCI0.GP41.ACPD)
    {
        Method (_WOV, 0, NotSerialized)
        {
            Return (One)
        }
    }

Change-Id: Ide84f45f5ea2ae42d5efe71ac6d1595886157045
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/55029
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/common/block/acp/acp.c

@@ -52,6 +52,28 @@ static const char *acp_acpi_name(const struct device *dev)
 	return "ACPD";
 }
 
+static void acp_fill_wov_method(const struct device *dev)
+{
+	const struct soc_amd_common_config *cfg = soc_get_common_config();
+	const char *scope = acpi_device_path(dev);
+
+	if (!cfg->acp_config.dmic_present || !scope)
+		return;
+
+	/* For ACP DMIC hardware runtime detection on the platform, _WOV method is populated. */
+	acpigen_write_scope(scope); /* Scope */
+	acpigen_write_method("_WOV", 0);
+	acpigen_write_return_integer(1);
+	acpigen_write_method_end();
+	acpigen_write_scope_end();
+}
+
+static void acp_fill_ssdt(const struct device *dev)
+{
+	acpi_device_write_pci_dev(dev);
+	acp_fill_wov_method(dev);
+}
+
 static struct device_operations acp_ops = {
 	.read_resources = pci_dev_read_resources,
 	.set_resources = pci_dev_set_resources,
@@ -60,7 +82,7 @@ static struct device_operations acp_ops = {
 	.ops_pci = &pci_dev_ops_pci,
 	.scan_bus = scan_static_bus,
 	.acpi_name = acp_acpi_name,
-	.acpi_fill_ssdt = acpi_device_write_pci_dev,
+	.acpi_fill_ssdt = acp_fill_ssdt,
 };
 
 static const struct pci_driver acp_driver __pci_driver = {

src/soc/amd/common/block/include/amdblocks/acp.h

@@ -4,6 +4,7 @@
 #define AMD_COMMON_ACP_H
 
 #include <stdint.h>
+#include <types.h>
 
 struct acp_config {
 	enum {
@@ -19,6 +20,12 @@ struct acp_config {
 	u8 acp_i2s_wake_enable;
 	/* Enable ACP PME (0 = disable, 1 = enable) */
 	u8 acp_pme_enable;
+
+	/*
+	 * DMIC present (optional) to support ACP DMIC hardware runtime detection on the
+	 * platform. If dmic_present is set to true, it will populate the _WOV ACPI method.
+	 */
+	bool dmic_present;
 };
 
 #endif /* AMD_COMMON_ACP_H */