Need to set platform wide _OSC bits to enable CPPC and CPPC version 2. If platform supports CPPC, then BIOS exposes CPPC tables. The primary reason to enable CPPC support is to get the maximum performance of each CPU to check and enable Intel Turbo Boost Max Technology 3.0 (ITMT). Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx> --- drivers/acpi/bus.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 85b7d07..61643a5 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -330,6 +330,13 @@ static void acpi_bus_osc_support(void) capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT; capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PCLPI_SUPPORT; +#ifdef CONFIG_X86 + if (boot_cpu_has(X86_FEATURE_HWP)) { + capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_SUPPORT; + capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPCV2_SUPPORT; + } +#endif + if (!ghes_disable) capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT; if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle))) -- 2.7.4 -- 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