diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/arm64/iort.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 9565d572f8dd..de56394dd161 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -1178,12 +1178,44 @@ dev_put: return ret; } +static bool __init iort_enable_acs(struct acpi_iort_node *iort_node) +{ + if (iort_node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) { + struct acpi_iort_node *parent; + struct acpi_iort_id_mapping *map; + int i; + + map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, iort_node, + iort_node->mapping_offset); + + for (i = 0; i < iort_node->mapping_count; i++, map++) { + if (!map->output_reference) + continue; + + parent = ACPI_ADD_PTR(struct acpi_iort_node, + iort_table, map->output_reference); + /* + * If we detect a RC->SMMU mapping, make sure + * we enable ACS on the system. + */ + if ((parent->type == ACPI_IORT_NODE_SMMU) || + (parent->type == ACPI_IORT_NODE_SMMU_V3)) { + pci_request_acs(); + return true; + } + } + } + + return false; +} + static void __init iort_init_platform_devices(void) { struct acpi_iort_node *iort_node, *iort_end; struct acpi_table_iort *iort; struct fwnode_handle *fwnode; int i, ret; + bool acs_enabled = false; /* * iort_table and iort both point to the start of IORT table, but @@ -1203,6 +1235,9 @@ static void __init iort_init_platform_devices(void) return; } + if (!acs_enabled) + acs_enabled = iort_enable_acs(iort_node); + if ((iort_node->type == ACPI_IORT_NODE_SMMU) || (iort_node->type == ACPI_IORT_NODE_SMMU_V3)) { |