Messages in this thread | | | From | "Yuan, Perry" <> | Subject | RE: [PATCH v4 3/9] cpufreq: amd-pstate: change amd-pstate driver to be built-in type | Date | Tue, 15 Nov 2022 02:02:14 +0000 |
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[AMD Official Use Only - General]
Hi Mario.
> -----Original Message----- > From: Limonciello, Mario <Mario.Limonciello@amd.com> > Sent: Tuesday, November 15, 2022 6:46 AM > To: Yuan, Perry <Perry.Yuan@amd.com>; rafael.j.wysocki@intel.com; Huang, > Ray <Ray.Huang@amd.com>; viresh.kumar@linaro.org > Cc: Sharma, Deepak <Deepak.Sharma@amd.com>; Fontenot, Nathan > <Nathan.Fontenot@amd.com>; Deucher, Alexander > <Alexander.Deucher@amd.com>; Huang, Shimmer > <Shimmer.Huang@amd.com>; Du, Xiaojian <Xiaojian.Du@amd.com>; Meng, > Li (Jassmine) <Li.Meng@amd.com>; Karny, Wyes <Wyes.Karny@amd.com>; > linux-pm@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH v4 3/9] cpufreq: amd-pstate: change amd-pstate driver > to be built-in type > > On 11/10/2022 11:58, Perry Yuan wrote: > > Change the `amd-pstate` driver as the built-in type which can help to > > load the driver before the acpi_cpufreq driver as the default pstate > > driver for the AMD processors. > > > > for the processors do not have the dedicated MSR functions, add > > `amd-pstate=legacy_cppc` to grub which enable shared memory interface > > to communicate with cppc_acpi module to control pstate hints. > > Did you sync with Wyes already as I had suggested? Was this the outcome? > > I was a bit surprised to see this still as legacy_cppc when reviewing v4.
The discussion we made will be in V5 soon. I am working on it.
> > > > > Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> > > --- > > drivers/cpufreq/Kconfig.x86 | 2 +- > > drivers/cpufreq/amd-pstate.c | 25 +++++++++++++++---------- > > 2 files changed, 16 insertions(+), 11 deletions(-) > > > > diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 > > index 310779b07daf..00476e94db90 100644 > > --- a/drivers/cpufreq/Kconfig.x86 > > +++ b/drivers/cpufreq/Kconfig.x86 > > @@ -35,7 +35,7 @@ config X86_PCC_CPUFREQ > > If in doubt, say N. > > > > config X86_AMD_PSTATE > > - tristate "AMD Processor P-State driver" > > + bool "AMD Processor P-State driver" > > depends on X86 && ACPI > > select ACPI_PROCESSOR > > select ACPI_CPPC_LIB if X86_64 > > diff --git a/drivers/cpufreq/amd-pstate.c > > b/drivers/cpufreq/amd-pstate.c index ace7d50cf2ac..85a0b3fb56c2 100644 > > --- a/drivers/cpufreq/amd-pstate.c > > +++ b/drivers/cpufreq/amd-pstate.c > > @@ -59,10 +59,7 @@ > > * we disable it by default to go acpi-cpufreq on these processors and add > a > > * module parameter to be able to enable it manually for debugging. > > */ > > -static bool shared_mem = false; > > -module_param(shared_mem, bool, 0444); - > MODULE_PARM_DESC(shared_mem, > > - "enable amd-pstate on processors with shared memory > solution (false = disabled (default), true = enabled)"); > > +static bool shared_mem __read_mostly; > > > > static struct cpufreq_driver amd_pstate_driver; > > > > @@ -653,16 +650,24 @@ static int __init amd_pstate_init(void) > > > > return ret; > > } > > +device_initcall(amd_pstate_init); > > > > -static void __exit amd_pstate_exit(void) > > +static int __init amd_pstate_param(char *str) > > { > > - cpufreq_unregister_driver(&amd_pstate_driver); > > + if (!str) > > + return -EINVAL; > > > > - amd_pstate_enable(false); > > -} > > + /* > > + * support shared memory type CPPC which has no MSR function. > > + * enable amd-pstate on processors with shared memory solution > > + * (amd-pstate=legacy_cppc enabled), it is disabled by default. > > + */ > > + if (!strcmp(str, "legacy_cppc")) > > + shared_mem = true; > > > > -module_init(amd_pstate_init); > > -module_exit(amd_pstate_exit); > > + return 0; > > +} > > +early_param("amd-pstate", amd_pstate_param); > > Documentation/kernel-parameters.txt needs to be updated for this early > parameter support.
Yeah, that will also be in V5 together.
> > > > > MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>"); > > MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver");
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