diff options
-rw-r--r-- | drivers/acpi/arm64/iort.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index f3bbef8bb15a..6aae49c35a95 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -318,6 +318,45 @@ static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, return 0; } +static +struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node, + u32 *id_out, u8 type_mask, + int index) +{ + struct acpi_iort_node *parent; + struct acpi_iort_id_mapping *map; + + if (!node->mapping_offset || !node->mapping_count || + index >= node->mapping_count) + return NULL; + + map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node, + node->mapping_offset); + + /* Firmware bug! */ + if (!map->output_reference) { + pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n", + node, node->type); + return NULL; + } + + parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, + map->output_reference); + + if (!(IORT_TYPE_MASK(parent->type) & type_mask)) + return NULL; + + if (map[index].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; + return parent; + } + } + + return NULL; +} + static struct acpi_iort_node *iort_node_map_rid(struct acpi_iort_node *node, u32 rid_in, u32 *rid_out, u8 type_mask) |