RE: [PATCH v9 03/13] cpufreq: intel_pstate: use common macro definition for Energy Preference Performance(EPP)

["Yuan, Perry" <Perry.Yuan@amd.com>]

[AMD Official Use Only - General]

Hi Mario. 

> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello@amd.com>
> Sent: Thursday, January 5, 2023 1:56 PM
> 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 v9 03/13] cpufreq: intel_pstate: use common macro
> definition for Energy Preference Performance(EPP)
> 
> On 1/4/23 23:49, Yuan, Perry wrote:
> > [AMD Official Use Only - General]
> >
> > Hi Mario
> >
> >> -----Original Message-----
> >> From: Limonciello, Mario <Mario.Limonciello@amd.com>
> >> Sent: Wednesday, January 4, 2023 8:31 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 v9 03/13] cpufreq: intel_pstate: use common macro
> >> definition for Energy Preference Performance(EPP)
> >>
> >> On 12/25/2022 10:34, Perry Yuan wrote:
> >>> make the energy preference performance strings and profiles using
> >>> one common header for intel_pstate driver, then the amd_pstate epp
> >>> driver can use the common header as well. This will simpify the
> >>> intel_pstate and amd_pstate driver.
> >>>
> >>> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
> >>> ---
> >>>    drivers/cpufreq/Kconfig.x86    |  2 +-
> >>>    drivers/cpufreq/intel_pstate.c | 13 +++----------
> >>>    include/linux/cpufreq.h        | 10 ++++++++++
> >>>    3 files changed, 14 insertions(+), 11 deletions(-)
> >>>
> >>> diff --git a/drivers/cpufreq/Kconfig.x86
> >>> b/drivers/cpufreq/Kconfig.x86 index 00476e94db90..f64aef1e093d
> >>> 100644
> >>> --- a/drivers/cpufreq/Kconfig.x86
> >>> +++ b/drivers/cpufreq/Kconfig.x86
> >>> @@ -36,7 +36,7 @@ config X86_PCC_CPUFREQ
> >>>
> >>>    config X86_AMD_PSTATE
> >>>    	bool "AMD Processor P-State driver"
> >>> -	depends on X86 && ACPI
> >>> +	depends on X86 && ACPI && X86_INTEL_PSTATE
> >>
> >> This doesn't seem right to me.  What if someone didn't compile in
> >> Intel
> >> x86 support for their kernel?  They wouldn't be able to pick
> >> X86_AMD_PSTATE.
> >
> > How about changed like this ? when amd pstate enabled, it will build intel-
> pstate.c as well.
> >
> >     depends on X86 && ACPI
> > + select X86_INTEL_PSTATE
> 
> I still don't think that's the right way to do this.  Why not move the variables
> to the cppc library file?  Both intel and amd pstate drivers select it, so it can
> be a common place both wil use.
> 
That will be good then. 
Ray suggested to put the code to cpufreq.h , I will move the code to cppc library in v10 if he has no objection. 

Perry.

> 
> >
> >
> >
> >>
> >>>    	select ACPI_PROCESSOR
> >>>    	select ACPI_CPPC_LIB if X86_64
> >>>    	select CPU_FREQ_GOV_SCHEDUTIL if SMP diff --git
> >>> a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
> >>> index ad9be31753b6..93a60fdac0fc 100644
> >>> --- a/drivers/cpufreq/intel_pstate.c
> >>> +++ b/drivers/cpufreq/intel_pstate.c
> >>> @@ -640,15 +640,7 @@ static int intel_pstate_set_epb(int cpu, s16 pref)
> >>>     *	4		power
> >>>     */
> >>>
> >>> -enum energy_perf_value_index {
> >>> -	EPP_INDEX_DEFAULT = 0,
> >>> -	EPP_INDEX_PERFORMANCE,
> >>> -	EPP_INDEX_BALANCE_PERFORMANCE,
> >>> -	EPP_INDEX_BALANCE_POWERSAVE,
> >>> -	EPP_INDEX_POWERSAVE,
> >>> -};
> >>> -
> >>> -static const char * const energy_perf_strings[] = {
> >>> +const char * const energy_perf_strings[] = {
> >>>    	[EPP_INDEX_DEFAULT] = "default",
> >>>    	[EPP_INDEX_PERFORMANCE] = "performance",
> >>>    	[EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance",
> >> @@ -656,7
> >>> +648,8 @@ static const char * const energy_perf_strings[] = {
> >>>    	[EPP_INDEX_POWERSAVE] = "power",
> >>>    	NULL
> >>>    };
> >>> -static unsigned int epp_values[] = {
> >>> +
> >>> +unsigned int epp_values[] = {
> >>>    	[EPP_INDEX_DEFAULT] = 0, /* Unused index */
> >>>    	[EPP_INDEX_PERFORMANCE] = HWP_EPP_PERFORMANCE,
> >>>    	[EPP_INDEX_BALANCE_PERFORMANCE] =
> >> HWP_EPP_BALANCE_PERFORMANCE, diff
> >>> --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index
> >>> d5595d57f4e5..0693269fb775 100644
> >>> --- a/include/linux/cpufreq.h
> >>> +++ b/include/linux/cpufreq.h
> >>> @@ -185,6 +185,16 @@ struct cpufreq_freqs {
> >>>    	u8 flags;		/* flags of cpufreq_driver, see below. */
> >>>    };
> >>>
> >>> +enum energy_perf_value_index {
> >>> +	EPP_INDEX_DEFAULT = 0,
> >>> +	EPP_INDEX_PERFORMANCE,
> >>> +	EPP_INDEX_BALANCE_PERFORMANCE,
> >>> +	EPP_INDEX_BALANCE_POWERSAVE,
> >>> +	EPP_INDEX_POWERSAVE,
> >>> +};
> >>> +extern const char * const energy_perf_strings[]; extern unsigned
> >>> +int epp_values[];
> >>> +
> >>>    /* Only for ACPI */
> >>>    #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
> >>>    #define CPUFREQ_SHARED_TYPE_HW	 (1) /* HW does needed
> >> coordination */
> >>
> >> I think the right place for these variables and strings is in the
> >> cppc library source file that is common across CPPC implementations.