ACPI : Use RSDT instead of XSDT by adding boot option of "acpi=rsdt"
On some boxes there exist both RSDT and XSDT table. But unfortunately
sometimes there exists the following error when XSDT table is used:
a. 32/64X address mismatch
b. The 32/64X FACS address mismatch
In such case the boot option of "acpi=rsdt" is provided so that
RSDT is tried instead of XSDT table when the system can't work well.
http://bugzilla.kernel.org/show_bug.cgi?id=8246
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
cc:Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/tables/tbutils.c b/drivers/acpi/tables/tbutils.c
index 0cc92ef..da9f240 100644
--- a/drivers/acpi/tables/tbutils.c
+++ b/drivers/acpi/tables/tbutils.c
@@ -420,7 +420,8 @@
/* Differentiate between RSDT and XSDT root tables */
- if (rsdp->revision > 1 && rsdp->xsdt_physical_address) {
+ if (rsdp->revision > 1 && rsdp->xsdt_physical_address
+ && !acpi_rsdt_forced) {
/*
* Root table is an XSDT (64-bit physical addresses). We must use the
* XSDT if the revision is > 1 and the XSDT pointer is present, as per