| From: Greg Pearson <greg.pearson@hp.com> |
| Date: Tue, 24 Apr 2012 18:23:56 -0600 |
| Subject: x86/apic: Use x2apic physical mode based on FADT setting |
| |
| commit ea0dcf903e7d76aa5d483d876215fedcfdfe140f upstream. |
| |
| Provide systems that do not support x2apic cluster mode |
| a mechanism to select x2apic physical mode using the |
| FADT FORCE_APIC_PHYSICAL_DESTINATION_MODE bit. |
| |
| Changes from v1: (based on Suresh's comments) |
| - removed #ifdef CONFIG_ACPI |
| - removed #include <linux/acpi.h> |
| |
| Signed-off-by: Greg Pearson <greg.pearson@hp.com> |
| Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> |
| Link: http://lkml.kernel.org/r/1335313436-32020-1-git-send-email-greg.pearson@hp.com |
| Signed-off-by: Ingo Molnar <mingo@kernel.org> |
| Signed-off-by: Ben Hutchings <ben@decadent.org.uk> |
| --- |
| arch/x86/kernel/apic/x2apic_phys.c | 6 ++++++ |
| 1 file changed, 6 insertions(+) |
| |
| --- a/arch/x86/kernel/apic/x2apic_phys.c |
| +++ b/arch/x86/kernel/apic/x2apic_phys.c |
| @@ -24,6 +24,12 @@ static int x2apic_acpi_madt_oem_check(ch |
| { |
| if (x2apic_phys) |
| return x2apic_enabled(); |
| + else if ((acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) && |
| + (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL) && |
| + x2apic_enabled()) { |
| + printk(KERN_DEBUG "System requires x2apic physical mode\n"); |
| + return 1; |
| + } |
| else |
| return 0; |
| } |
