Bit 11 in intel PDC definitions is meant for OS capability to handle hardware coordination of P-states. In Linux we have always supported hwardware coordination of P-states. Just let the BIOSes know that we support it, by setting this bit. Some BIOSes use this bit to choose between hardware or software coordination and without this change below, BIOSes switch to software coordination, which is not very optimal in terms of power consumption and extra wakeups from idle. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx> --- include/acpi/pdc_intel.h | 2 ++ 1 file changed, 2 insertions(+) Index: linux-2.6/include/acpi/pdc_intel.h =================================================================== --- linux-2.6.orig/include/acpi/pdc_intel.h 2009-01-20 16:11:20.000000000 -0800 +++ linux-2.6/include/acpi/pdc_intel.h 2009-02-02 10:32:06.000000000 -0800 @@ -14,6 +14,7 @@ #define ACPI_PDC_SMP_T_SWCOORD (0x0080) #define ACPI_PDC_C_C1_FFH (0x0100) #define ACPI_PDC_C_C2C3_FFH (0x0200) +#define ACPI_PDC_SMP_P_HWCOORD (0x0800) #define ACPI_PDC_EST_CAPABILITY_SMP (ACPI_PDC_SMP_C1PT | \ ACPI_PDC_C_C1_HALT | \ @@ -22,6 +23,7 @@ #define ACPI_PDC_EST_CAPABILITY_SWSMP (ACPI_PDC_SMP_C1PT | \ ACPI_PDC_C_C1_HALT | \ ACPI_PDC_SMP_P_SWCOORD | \ + ACPI_PDC_SMP_P_HWCOORD | \ ACPI_PDC_P_FFH) #define ACPI_PDC_C_CAPABILITY_SMP (ACPI_PDC_SMP_C2C3 | \ -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
