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/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index bd7acc7..c19b686 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -65,6 +65,7 @@
void (*pm_power_off) (void);
EXPORT_SYMBOL(pm_power_off);
+u32 acpi_rsdt_forced;
unsigned int acpi_cpei_override;
unsigned int acpi_cpei_phys_cpuid;
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 4c51a2f..db1a90a 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -47,7 +47,7 @@
#endif
static int __initdata acpi_force = 0;
-
+u32 acpi_rsdt_forced;
#ifdef CONFIG_ACPI
int acpi_disabled = 0;
#else
@@ -1783,6 +1783,10 @@
disable_acpi();
acpi_ht = 1;
}
+ /* acpi=rsdt use RSDT instead of XSDT */
+ else if (strcmp(arg, "rsdt") == 0) {
+ acpi_rsdt_forced = 1;
+ }
/* "acpi=noirq" disables ACPI interrupt routing */
else if (strcmp(arg, "noirq") == 0) {
acpi_noirq_set();
