Commit 07d2e59f authored Jun 19, 2020 by Lorenzo Pieralisi Committed by Catalin Marinas Jul 28, 2020

ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC



When the iort_match_node_callback is invoked for a named component
the match should be executed upon a device with an ACPI companion.

For devices with no ACPI companion set-up the ACPI device tree must be
walked in order to find the first parent node with a companion set and
check the parent node against the named component entry to check whether
there is a match and therefore an IORT node describing the in/out ID
translation for the device has been found.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Link: https://lore.kernel.org/r/20200619082013.13661-2-lorenzo.pieralisi@arm.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

parent 9ebcfadb

drivers/acpi/arm64/iort.c

+18 −2

Original line number	Diff line number	Diff line
		@@ -264,15 +264,31 @@ static acpi_status iort_match_node_callback(struct acpi_iort_node *node,

		if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT) {
		struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
		struct acpi_device *adev = to_acpi_device_node(dev->fwnode);
		struct acpi_device *adev;
		struct acpi_iort_named_component *ncomp;
		struct device *nc_dev = dev;

		/*
		* Walk the device tree to find a device with an
		* ACPI companion; there is no point in scanning
		* IORT for a device matching a named component if
		* the device does not have an ACPI companion to
		* start with.
		*/
		do {
		adev = ACPI_COMPANION(nc_dev);
		if (adev)
		break;

		nc_dev = nc_dev->parent;
		} while (nc_dev);

		if (!adev)
		goto out;

		status = acpi_get_name(adev->handle, ACPI_FULL_PATHNAME, &buf);
		if (ACPI_FAILURE(status)) {
		dev_warn(dev, "Can't get device full path name\n");
		dev_warn(nc_dev, "Can't get device full path name\n");
		goto out;
		}

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