| Message ID | 20240730140111.4491-1-00107082@163.com |
|---|---|
| State | New |
| Headers | show |
| Series | [Regression] 6.11.0-rc1: AMD CPU boot with error when CPPC feature disabled by BIOS | expand |
Hello David, "David Wang" <00107082@163.com> writes: > Hi, > > At 2024-07-31 18:12:12, "Gautham R.Shenoy" <gautham.shenoy@amd.com> wrote: >>Hello David, >> >>David Wang <00107082@163.com> writes: >> >>> Hi, >>> >>> I notice some kernel warning and errors when I update to 6.11.0-rc1: >>> >>> kernel: [ 1.022739] amd_pstate: The CPPC feature is supported but currently disabled by the BIOS. >>> kernel: [ 1.022739] Please enable it if your BIOS has the CPPC option. >>> kernel: [ 1.098054] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.110058] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.122057] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.134062] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.134641] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.135128] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.135693] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.136371] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.136390] amd_pstate: failed to register with return -19 >>> kernel: [ 1.138410] ledtrig-cpu: registered to indicate activity on CPUs >>> >>> >>> Those warning message was introduced by commit: >>> bff7d13c190ad98cf4f877189b022c75df4cb383 ("cpufreq: amd-pstate: add debug message while CPPC is supported and disabled by SBIOS) >>> , which make sense. >> >> >>If CPPC is disabed in the BIOS, then the _CPC objects shouldn't have >>been created. And the error message that you should have seen is >>"the _CPC object is not present in SBIOS or ACPI disabled". >> >> >>Could you please share the family and model number of the platform where >>you are observing this ? > > My `cat /proc/cpuinfo` shows something as following: > processor : 0 > vendor_id : AuthenticAMD > cpu family : 23 > model : 113 This is Family 0x17 (Zen2), Model 0x71. AFAIK, this processor supports CPPC but does not have the support for the CPPC MSRs. Hence the CPPC communication occurs via shared-memory. Hence the warning introduced by the commit bff7d13c190a ("cpufreq: amd-pstate: add debug message while CPPC is supported and disabled by SBIOS") is not applicable on your platform. I will send a patch to rectify this which avoids the warning for Zen2 Models 0x70-0x7F. Regarding the following errors that you are observing >>> kernel: [ 1.098054] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.110058] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.122057] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.134062] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.134641] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.135128] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.135693] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.136371] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect >>> kernel: [ 1.136390] amd_pstate: failed to register with return -19 it appears that the CPPC version on your platform is v2 which does not advertise the nominal_freq and the lowest_freq. In the absence of these, it is not possible for the amd-pstate driver to infer the min/max_freq. Which is why the driver bails at this later stage. The way around it is to add a quirk for your BIOS as done in this commit from Perry: eb8b6c368202 ("cpufreq: amd-pstate: Add quirk for the pstate CPPC capabilities missing") -- Thanks and Regards gautham.
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 68c616b572f2..b06faea58fd4 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -1837,8 +1837,6 @@ static bool amd_cppc_supported(void) * If the CPPC feature is disabled in the BIOS for processors that support MSR-based CPPC, * the AMD Pstate driver may not function correctly. * Check the CPPC flag and display a warning message if the platform supports CPPC. - * Note: below checking code will not abort the driver registeration process because of - * the code is added for debugging purposes. */ if (!cpu_feature_enabled(X86_FEATURE_CPPC)) { if (cpu_feature_enabled(X86_FEATURE_ZEN1) || cpu_feature_enabled(X86_FEATURE_ZEN2)) { @@ -1856,6 +1854,7 @@ static bool amd_cppc_supported(void) if (warn) pr_warn_once("The CPPC feature is supported but currently disabled by the BIOS.\n" "Please enable it if your BIOS has the CPPC option.\n"); + return false; return true; }
Hi, I notice some kernel warning and errors when I update to 6.11.0-rc1: kernel: [ 1.022739] amd_pstate: The CPPC feature is supported but currently disabled by the BIOS. kernel: [ 1.022739] Please enable it if your BIOS has the CPPC option. kernel: [ 1.098054] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.110058] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.122057] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.134062] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.134641] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.135128] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.135693] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.136371] amd_pstate: min_freq(0) or max_freq(0) or nominal_freq(0) value is incorrect kernel: [ 1.136390] amd_pstate: failed to register with return -19 kernel: [ 1.138410] ledtrig-cpu: registered to indicate activity on CPUs Those warning message was introduced by commit: bff7d13c190ad98cf4f877189b022c75df4cb383 ("cpufreq: amd-pstate: add debug message while CPPC is supported and disabled by SBIOS) , which make sense. Those error message was introduced by commit: 8f8b42c1fcc939a73b547b172a9ffcb65ef4bf47 ("cpufreq: amd-pstate: optimize the initial frequency values verification") , when CPPC is disabled by BIOS, this error message does not make sense, and the error return-code would abort the driver registeration, but this behavior could be handled earlier when detecting CPPC feature. I feel following changes would make a clean fix: do not register amd_pstate driver when CPPC disabled by BIOS. Thanks David