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authorBob Moore <robert.moore@intel.com>2011-11-16 10:57:28 +0800
committerLen Brown <len.brown@intel.com>2012-01-17 03:36:28 -0500
commit22e5b40ab21fcac21db0ff25fbb844ffecc73a4a (patch)
tree6fe339a8c410d2f8f2a0f844c976046d3be47e17 /drivers/acpi/acpica/tbfadt.c
parent2355e10f07b2c550c671f98b68aedf323c299aeb (diff)
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ACPI 5.0: Implement hardware-reduced option
If HW-reduced flag is set in the FADT, do not attempt to access or initialize any ACPI hardware, including SCI and global lock. No FACS will be present. Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/acpica/tbfadt.c')
-rw-r--r--drivers/acpi/acpica/tbfadt.c22
1 files changed, 20 insertions, 2 deletions
diff --git a/drivers/acpi/acpica/tbfadt.c b/drivers/acpi/acpica/tbfadt.c
index 536fd2bc7a47..1e1a7de34439 100644
--- a/drivers/acpi/acpica/tbfadt.c
+++ b/drivers/acpi/acpica/tbfadt.c
@@ -253,8 +253,13 @@ void acpi_tb_parse_fadt(u32 table_index)
acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
- acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xfacs,
- ACPI_SIG_FACS, ACPI_TABLE_INDEX_FACS);
+ /* If Hardware Reduced flag is set, there is no FACS */
+
+ if (!acpi_gbl_reduced_hardware) {
+ acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.
+ Xfacs, ACPI_SIG_FACS,
+ ACPI_TABLE_INDEX_FACS);
+ }
}
/*******************************************************************************
@@ -297,6 +302,13 @@ void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
ACPI_MEMCPY(&acpi_gbl_FADT, table,
ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
+ /* Take a copy of the Hardware Reduced flag */
+
+ acpi_gbl_reduced_hardware = FALSE;
+ if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
+ acpi_gbl_reduced_hardware = TRUE;
+ }
+
/* Convert the local copy of the FADT to the common internal format */
acpi_tb_convert_fadt();
@@ -502,6 +514,12 @@ static void acpi_tb_validate_fadt(void)
acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
}
+ /* If Hardware Reduced flag is set, we are all done */
+
+ if (acpi_gbl_reduced_hardware) {
+ return;
+ }
+
/* Examine all of the 64-bit extended address fields (X fields) */
for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {