Messages in this thread | | | From | Perry Yuan <> | Subject | [PATCH 0/5] AMD Pstate driver Urgent Change | Date | Thu, 17 Nov 2022 10:49:50 +0800 |
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The patchset changed amd-pstate driver as built-in type to resolve the driver loading sequence problem, otherwise the acpi-cpufreq driver will be loaded as the default cpufreq scaling driver instead of amd-pstate.
Some new kernel parameters are added to allow user to disable pstate driver and load driver with passive mode which use governors to do the frequency scaling control.
* `amd_pstate=disabled` or no parameters will not load pstate driver. * `amd_pstate=passive` will load pstate driver with passive mode.
Set the `amd_pstate` driver disabled by default because of performance degradation on a number of AMD ASICs in the passive mode driver, especially the shared memory support processors.
EPP support for the amd_pstate driver is under review. With EPP support, the said performance issue is resolved. Once that gets upstream, the `active` mode amd_pstate_epp driver may be enabled by default.
Perry Yuan (4): cpufreq: amd-pstate: change amd-pstate driver to be built-in type cpufreq: amd-pstate: add amd-pstate driver parameter for mode selection Documentation: amd-pstate: add driver working mode introduction Documentation: add amd-pstate kernel command line options
Wyes Karny (1): cpufreq: amd-pstate: cpufreq: amd-pstate: reset MSR_AMD_PERF_CTL register at init
.../admin-guide/kernel-parameters.txt | 11 +++++ Documentation/admin-guide/pm/amd-pstate.rst | 30 +++++------- drivers/cpufreq/Kconfig.x86 | 2 +- drivers/cpufreq/amd-pstate.c | 49 +++++++++++++------ 4 files changed, 59 insertions(+), 33 deletions(-)
-- 2.25.1
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