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authorMario Limonciello <mario.limonciello@amd.com>2022-07-05 21:29:14 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-07-05 21:36:11 +0300
commit7feec7430edddb87c24b0a86b08a03d0b496a755 (patch)
tree52f12c34344cda0070472741c38b7e830a1e7bb9 /drivers/acpi/cppc_acpi.c
parent88084a3df1672e131ddc1b4e39eeacfd39864acf (diff)
downloadlinux-7feec7430edddb87c24b0a86b08a03d0b496a755.tar.xz
ACPI: CPPC: Only probe for _CPC if CPPC v2 is acked
Previously the kernel used to ignore whether the firmware masked CPPC or CPPCv2 and would just pretend that it worked. When support for the USB4 bit in _OSC was introduced from commit 9e1f561afb ("ACPI: Execute platform _OSC also with query bit clear") the kernel began to look at the return when the query bit was clear. This caused regressions that were misdiagnosed and attempted to be solved as part of commit 2ca8e6285250 ("Revert "ACPI: Pass the same capabilities to the _OSC regardless of the query flag""). This caused a different regression where non-Intel systems weren't able to negotiate _OSC properly. This was reverted in commit 2ca8e6285250 ("Revert "ACPI: Pass the same capabilities to the _OSC regardless of the query flag"") and attempted to be fixed by commit c42fa24b4475 ("ACPI: bus: Avoid using CPPC if not supported by firmware") but the regression still returned. These systems with the regression only load support for CPPC from an SSDT dynamically when _OSC reports CPPC v2. Avoid the problem by not letting CPPC satisfy the requirement in `acpi_cppc_processor_probe`. Reported-by: CUI Hao <cuihao.leo@gmail.com> Reported-by: maxim.novozhilov@gmail.com Reported-by: lethe.tree@protonmail.com Reported-by: garystephenwright@gmail.com Reported-by: galaxyking0419@gmail.com Fixes: c42fa24b4475 ("ACPI: bus: Avoid using CPPC if not supported by firmware") Fixes: 2ca8e6285250 ("Revert "ACPI Pass the same capabilities to the _OSC regardless of the query flag"") Link: https://bugzilla.kernel.org/show_bug.cgi?id=213023 Link: https://bugzilla.redhat.com/show_bug.cgi?id=2075387 Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: CUI Hao <cuihao.leo@gmail.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/cppc_acpi.c')
-rw-r--r--drivers/acpi/cppc_acpi.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 903528f7e187..d64facbda0fb 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -684,8 +684,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
acpi_status status;
int ret = -ENODATA;
- if (osc_sb_cppc_not_supported)
+ if (!osc_sb_cppc2_support_acked) {
+ pr_debug("CPPC v2 _OSC not acked\n");
return -ENODEV;
+ }
/* Parse the ACPI _CPC table for this CPU. */
status = acpi_evaluate_object_typed(handle, "_CPC", NULL, &output,