Messages in this thread | | | Date | Fri, 1 Jul 2022 08:48:40 +0300 | From | Mika Westerberg <> | Subject | Re: [PATCH v3 1/2] ACPI: CPPC: Only probe for _CPC if CPPC v2 is acked |
| |
On Thu, Jun 30, 2022 at 09:25:27PM -0500, Mario Limonciello wrote: > 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 > Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
| |