diff options
-rw-r--r-- | drivers/acpi/arm64/iort.c | 57 |
1 files changed, 55 insertions, 2 deletions
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 33f71983e001..6078064684c6 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -298,6 +298,59 @@ out: return status; } +struct iort_workaround_oem_info { + char oem_id[ACPI_OEM_ID_SIZE + 1]; + char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1]; + u32 oem_revision; +}; + +static bool apply_id_count_workaround; + +static struct iort_workaround_oem_info wa_info[] __initdata = { + { + .oem_id = "HISI ", + .oem_table_id = "HIP07 ", + .oem_revision = 0, + }, { + .oem_id = "HISI ", + .oem_table_id = "HIP08 ", + .oem_revision = 0, + } +}; + +static void __init +iort_check_id_count_workaround(struct acpi_table_header *tbl) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(wa_info); i++) { + if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) && + !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && + wa_info[i].oem_revision == tbl->oem_revision) { + apply_id_count_workaround = true; + pr_warn(FW_BUG "ID count for ID mapping entry is wrong, applying workaround\n"); + break; + } + } +} + +static inline u32 iort_get_map_max(struct acpi_iort_id_mapping *map) +{ + u32 map_max = map->input_base + map->id_count; + + /* + * The IORT specification revision D (Section 3, table 4, page 9) says + * Number of IDs = The number of IDs in the range minus one, but the + * IORT code ignored the "minus one", and some firmware did that too, + * so apply a workaround here to keep compatible with both the spec + * compliant and non-spec compliant firmwares. + */ + if (apply_id_count_workaround) + map_max--; + + return map_max; +} + static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, u32 *rid_out) { @@ -314,8 +367,7 @@ static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, return -ENXIO; } - if (rid_in < map->input_base || - (rid_in >= map->input_base + map->id_count)) + if (rid_in < map->input_base || rid_in > iort_get_map_max(map)) return -ENXIO; *rid_out = map->output_base + (rid_in - map->input_base); @@ -1631,5 +1683,6 @@ void __init acpi_iort_init(void) return; } + iort_check_id_count_workaround(iort_table); iort_init_platform_devices(); } |