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authorLorenzo Pieralisi <lorenzo.pieralisi@arm.com>2017-01-05 17:32:16 +0000
committerWill Deacon <will.deacon@arm.com>2017-02-06 18:59:37 +0000
commit030abd8a5d33057524c6c11c28d3191f3b5c63f6 (patch)
tree5c5a27b8b9c32a2a859ac19d6128d5db8ba6d4a9 /drivers/acpi/arm64
parent6d526ee26ccdcbf8eb9ddd0b584b35ac17f8c566 (diff)
downloadlinux-030abd8a5d33057524c6c11c28d3191f3b5c63f6.tar.bz2
ACPI/IORT: Fix iort_node_get_id() mapping entries indexing
Commit 618f535a6062 ("ACPI/IORT: Add single mapping function") introduced a function (iort_node_get_id()) to retrieve ids for IORT named components. The iort_node_get_id() takes an index as input to refer to a specific mapping entry in the named component IORT node mapping array. For a mapping entry at a given index, iort_node_get_id() should return the id value (through the id_out function parameter) and the IORT node output_reference (through function return value) the given mapping entry refers to. Technically output_reference values may differ for different map entries, (see diagram below - mapped id values may refer to different eg IORT SMMU nodes; the kernel may not be able to handle different output_reference values for a given named component but the IORT kernel layer should still report the IORT mappings as reported by firmware) but current code in iort_node_get_id() fails to use the index function parameter to return the correct output_reference value (ie it always returns the output_reference value of the first entry in the mapping array whilst using the index correctly to retrieve the id value from the respective entry). |----------------------| | named component | |----------------------| | map entry[0] | |----------------------| | id value | | output_reference----------------> eg SMMU 1 |----------------------| | map entry[1] | |----------------------| | id value | | output_reference----------------> eg SMMU 2 |----------------------| . . . |----------------------| | map entry[N] | |----------------------| | id value | | output_reference----------------> eg SMMU 1 |----------------------| Consequently the iort_node_get_id() function always returns the IORT node pointed at by the output_reference value of the first named component mapping array entry, irrespective of the index parameter, which is a bug. Update the map array entry pointer computation in iort_node_get_id() to take into account the index value, fixing the issue. Fixes: 618f535a6062 ("ACPI/IORT: Add single mapping function") Reported-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Sinan Kaya <okaya@codeaurora.org> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Nate Watterson <nwatters@codeaurora.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers/acpi/arm64')
-rw-r--r--drivers/acpi/arm64/iort.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index e0d2e6e6e40c..ba156c5afc16 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -333,7 +333,7 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
return NULL;
map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
- node->mapping_offset);
+ node->mapping_offset + index * sizeof(*map));
/* Firmware bug! */
if (!map->output_reference) {
@@ -348,10 +348,10 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
if (!(IORT_TYPE_MASK(parent->type) & type_mask))
return NULL;
- if (map[index].flags & ACPI_IORT_ID_SINGLE_MAPPING) {
+ if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {
if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT ||
node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
- *id_out = map[index].output_base;
+ *id_out = map->output_base;
return parent;
}
}