2 files changed, 27 insertions, 8 deletions

diff --git a/src/drivers/pcie/generic/chip.h b/src/drivers/pcie/generic/chip.h
index 3be57de530..5d762ec250 100644
--- a/src/drivers/pcie/generic/chip.h
+++ b/src/drivers/pcie/generic/chip.h
@@ -7,6 +7,14 @@
 
 struct drivers_pcie_generic_config {
 	bool is_untrusted;
+	/*
+	 * This needs to be pointed to the device instance in the device tree when
+	 * there is already a device with the root port so that the ACPI code to be
+	 * generated will be added to that existing device.
+	 * By default, an ACPI device named 'DEV0' is created under the root port if
+	 * this does not reference to a device.
+	 */
+	DEVTREE_CONST struct device *companion_dev;
 };
 
 #endif /* _PCIE_GENERIC_H_ */
diff --git a/src/drivers/pcie/generic/generic.c b/src/drivers/pcie/generic/generic.c
index c14628f65b..0a9a243518 100644
--- a/src/drivers/pcie/generic/generic.c
+++ b/src/drivers/pcie/generic/generic.c
@@ -9,6 +9,10 @@
 
 static const char *pcie_generic_acpi_name(const struct device *dev)
 {
+	struct drivers_pcie_generic_config *config = dev->chip_info;
+
+	if (config->companion_dev)
+		return acpi_device_name(config->companion_dev);
 	return "DEV0";
 }
 
@@ -26,22 +30,29 @@ static void pcie_generic_fill_ssdt(const struct device *dev)
 	if (!config || !config->is_untrusted || !dev->bus || !dev->bus->dev)
 		return;
 
-	const char *scope = acpi_device_path(dev->bus->dev);
-	const char *name = acpi_device_name(dev);
+	const char *scope;
+	const char *name;
 
+	/* Code will be generated under companion device instead if present. */
+	if (config->companion_dev)
+		scope = acpi_device_path(config->companion_dev);
+	else
+		scope = acpi_device_path(dev->bus->dev);
+	name = acpi_device_name(dev);
 	acpigen_write_scope(scope);
-	acpigen_write_device(name);
-	acpigen_write_ADR_pci_device(dev);
-
+	if (!config->companion_dev) {
+		acpigen_write_device(name);
+		acpigen_write_ADR_pci_device(dev);
+	}
 	dsd = acpi_dp_new_table("_DSD");
 	acpi_dp_add_integer(dsd, "DmaProperty", 1);
 	acpi_dp_write(dsd);
-
-	acpigen_write_device_end();
+	if (!config->companion_dev)
+		acpigen_write_device_end();
 	acpigen_write_scope_end();
 
 	printk(BIOS_INFO, "%s.%s: Enable ACPI properties for %s (%s)\n", scope, name,
-	       dev_path(dev), dev->chip_ops->name);
+		dev_path(dev), dev->chip_ops->name);
 }
 
 struct device_operations pcie_generic_ops = {