From 22e5b40ab21fcac21db0ff25fbb844ffecc73a4a Mon Sep 17 00:00:00 2001 From: Bob Moore Date: Wed, 16 Nov 2011 10:57:28 +0800 Subject: 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 Signed-off-by: Lin Ming Signed-off-by: Len Brown --- drivers/acpi/acpica/tbfadt.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) (limited to 'drivers/acpi/acpica/tbfadt.c') 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++) { -- cgit