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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-03-16 13:39:03 +0100
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-03-17 14:51:53 +0100
commitc42fa24b44751c62c86e98430ef915c0609a2ab8 (patch)
tree18abd2aa653a3b5443236f6eb1a12586785a0e8a /drivers/acpi/bus.c
parent2ca8e6285250c07a2e5a22ecbfd59b5a4ef73484 (diff)
ACPI: bus: Avoid using CPPC if not supported by firmware
If the platform firmware indicates that it does not support CPPC by clearing the OSC_SB_CPC_SUPPORT and OSC_SB_CPCV2_SUPPORT bits in the platform _OSC capabilities mask, avoid attempting to evaluate _CPC which may fail in that case. Because the OSC_SB_CPC_SUPPORT and OSC_SB_CPCV2_SUPPORT bits are only added to the supported platform capabilities mask on x86, when X86_FEATURE_HWP is supported, allow _CPC to be evaluated regardless in the other cases. Link: https://lore.kernel.org/linux-acpi/CAJZ5v0i=ecAksq0TV+iLVObm-=fUfdqPABzzkgm9K6KxO1ZCcg@mail.gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Diffstat (limited to 'drivers/acpi/bus.c')
-rw-r--r--drivers/acpi/bus.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index c7670d441ad9..8aa7860602e7 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -283,6 +283,8 @@ EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed);
bool osc_sb_native_usb4_support_confirmed;
EXPORT_SYMBOL_GPL(osc_sb_native_usb4_support_confirmed);
+bool osc_sb_cppc_not_supported;
+
static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
static void acpi_bus_osc_negotiate_platform_control(void)
{
@@ -338,6 +340,12 @@ static void acpi_bus_osc_negotiate_platform_control(void)
return;
}
+#ifdef CONFIG_X86
+ if (boot_cpu_has(X86_FEATURE_HWP))
+ osc_sb_cppc_not_supported = !(capbuf_ret[OSC_SUPPORT_DWORD] &
+ (OSC_SB_CPC_SUPPORT | OSC_SB_CPCV2_SUPPORT));
+#endif
+
/*
* Now run _OSC again with query flag clear and with the caps
* supported by both the OS and the platform.