*
* RETURN: None
*
- * DESCRIPTION: Install an ACPI table into the global data structure.
+ * DESCRIPTION: Install an ACPI table into the global data structure. The
+ * table override mechanism is implemented here to allow the host
+ * OS to replace any table before it is installed in the root
+ * table array.
*
******************************************************************************/
acpi_tb_install_table(acpi_physical_address address,
u8 flags, char *signature, u32 table_index)
{
- struct acpi_table_header *table;
+ acpi_status status;
+ struct acpi_table_header *table_to_install;
+ struct acpi_table_header *mapped_table;
+ struct acpi_table_header *override_table = NULL;
if (!address) {
ACPI_ERROR((AE_INFO,
/* Map just the table header */
- table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
- if (!table) {
+ mapped_table =
+ acpi_os_map_memory(address, sizeof(struct acpi_table_header));
+ if (!mapped_table) {
return;
}
- /* If a particular signature is expected, signature must match */
+ /* If a particular signature is expected (DSDT/FACS), it must match */
- if (signature && !ACPI_COMPARE_NAME(table->signature, signature)) {
+ if (signature && !ACPI_COMPARE_NAME(mapped_table->signature, signature)) {
ACPI_ERROR((AE_INFO,
- "Invalid signature 0x%X for ACPI table [%s]",
- *ACPI_CAST_PTR(u32, table->signature), signature));
+ "Invalid signature 0x%X for ACPI table, expected [%s]",
+ *ACPI_CAST_PTR(u32, mapped_table->signature),
+ signature));
goto unmap_and_exit;
}
+ /*
+ * ACPI Table Override:
+ *
+ * Before we install the table, let the host OS override it with a new
+ * one if desired. Any table within the RSDT/XSDT can be replaced,
+ * including the DSDT which is pointed to by the FADT.
+ */
+ status = acpi_os_table_override(mapped_table, &override_table);
+ if (ACPI_SUCCESS(status) && override_table) {
+ ACPI_INFO((AE_INFO,
+ "%4.4s @ 0x%p Table override, replaced with:",
+ mapped_table->signature, ACPI_CAST_PTR(void,
+ address)));
+
+ acpi_gbl_root_table_list.tables[table_index].pointer =
+ override_table;
+ flags = ACPI_TABLE_ORIGIN_OVERRIDE;
+ address = ACPI_PTR_TO_PHYSADDR(override_table);
+
+ table_to_install = override_table;
+ } else {
+ table_to_install = mapped_table;
+ }
+
/* Initialize the table entry */
acpi_gbl_root_table_list.tables[table_index].address = address;
- acpi_gbl_root_table_list.tables[table_index].length = table->length;
+ acpi_gbl_root_table_list.tables[table_index].length =
+ table_to_install->length;
acpi_gbl_root_table_list.tables[table_index].flags = flags;
ACPI_MOVE_32_TO_32(&
(acpi_gbl_root_table_list.tables[table_index].
- signature), table->signature);
+ signature), table_to_install->signature);
- acpi_tb_print_table_header(address, table);
+ acpi_tb_print_table_header(address, table_to_install);
if (table_index == ACPI_TABLE_INDEX_DSDT) {
/* Global integer width is based upon revision of the DSDT */
- acpi_ut_set_integer_width(table->revision);
+ acpi_ut_set_integer_width(table_to_install->revision);
}
unmap_and_exit:
- acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
+ acpi_os_unmap_memory(mapped_table, sizeof(struct acpi_table_header));
}
/*******************************************************************************
static acpi_status acpi_tb_load_namespace(void)
{
acpi_status status;
- struct acpi_table_header *table;
u32 i;
ACPI_FUNCTION_TRACE(tb_load_namespace);
goto unlock_and_exit;
}
- /*
- * Find DSDT table
- */
- status =
- acpi_os_table_override(acpi_gbl_root_table_list.
- tables[ACPI_TABLE_INDEX_DSDT].pointer,
- &table);
- if (ACPI_SUCCESS(status) && table) {
- /*
- * DSDT table has been found
- */
- acpi_tb_delete_table(&acpi_gbl_root_table_list.
- tables[ACPI_TABLE_INDEX_DSDT]);
- acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].pointer =
- table;
- acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].length =
- table->length;
- acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].flags =
- ACPI_TABLE_ORIGIN_UNKNOWN;
-
- ACPI_INFO((AE_INFO, "Table DSDT replaced by host OS"));
- acpi_tb_print_table_header(0, table);
-
- if (no_auto_ssdt == 0) {
- printk(KERN_WARNING "ACPI: DSDT override uses original SSDTs unless \"acpi_no_auto_ssdt\"\n");
- }
- }
+ /* A valid DSDT is required */
status =
acpi_tb_verify_table(&acpi_gbl_root_table_list.
tables[ACPI_TABLE_INDEX_DSDT]);
if (ACPI_FAILURE(status)) {
- /* A valid DSDT is required */
-
status = AE_NO_ACPI_TABLES;
goto unlock_and_exit;
}