From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas Pandruvada Subject: Re: [PATCH 1/5] acpi: cppc: Allow build with ACPI_CPU_FREQ_PSS config Date: Fri, 12 Aug 2016 10:16:21 -0700 Message-ID: <1471022181.3745.13.camel@linux.intel.com> References: <1470874646-70570-1-git-send-email-srinivas.pandruvada@linux.intel.com> <1470874646-70570-2-git-send-email-srinivas.pandruvada@linux.intel.com> <1471020739.3745.10.camel@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org To: Hoan Tran Cc: "Rafael J. Wysocki" , viresh.kumar@linaro.org, linux acpi , linux-pm@vger.kernel.org, Ashwin Chaugule List-Id: linux-pm@vger.kernel.org On Fri, 2016-08-12 at 09:58 -0700, Hoan Tran wrote: > Hi Srinivas, > > On Fri, Aug 12, 2016 at 9:52 AM, Srinivas Pandruvada > wrote: > > > > On Fri, 2016-08-12 at 09:35 -0700, Hoan Tran wrote: > > > > > > Hi Srinivas, > > > > > > On Wed, Aug 10, 2016 at 5:17 PM, Srinivas Pandruvada > > > wrote: > > > > > > > > > > > > Some newer x86 platforms have support for both _CPC and _PSS > > > > object. So > > > > kernel config can have both ACPI_CPU_FREQ_PSS and > > > > ACPI_CPPC_LIB. So > > > > remove > > > > restriction for ACPI_CPPC_LIB to build only when > > > > ACPI_CPU_FREQ_PSS > > > > is not > > > > defined. > > > > Also for legacy systems with only _PSS, we shouldn't bail out > > > > if > > > > acpi_cppc_processor_probe() fails, if ACPI_CPU_FREQ_PSS is also > > > > defined. > > > > > > > > Signed-off-by: Srinivas Pandruvada > > > ntel > > > > .com> > > > > --- > > > >  drivers/acpi/Kconfig            | 1 - > > > >  drivers/acpi/processor_driver.c | 5 ++++- > > > >  2 files changed, 4 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig > > > > index 445ce28..c6bb6aa 100644 > > > > --- a/drivers/acpi/Kconfig > > > > +++ b/drivers/acpi/Kconfig > > > > @@ -227,7 +227,6 @@ config ACPI_MCFG > > > >  config ACPI_CPPC_LIB > > > >         bool > > > >         depends on ACPI_PROCESSOR > > > > -       depends on !ACPI_CPU_FREQ_PSS > > > From ACPI 6.1 spec, if _CPC is present, its use supersedes the > > > use of > > > PSS. So I think, config ACPI_CPU_FREQ_PSS should depend on > > > !ACPI_CPPC_LIB. > > > > > Distro want to have a single binary kernel image, so they will turn > > on > > all configs. So this is not a compile time decision. > > On runtime if the ACPI contains both tables than _CPC should be > > used > > (but that also if the kernel is capable of handling _CPC, as legacy > > kernel will not). > Agreed. If so, this "depends on" is not need, right ? And a runtime > code will be added to decide which is used instead ? Yes, _CPC will be used if present.  Thanks, Srinivas > > Thanks > Hoan > > > > > > > Thanks, > > Srinivas > > > > > > > > Thanks > > > Hoan > > > > > > > > > > > > > > >         select MAILBOX > > > >         select PCC > > > >         help > > > > diff --git a/drivers/acpi/processor_driver.c > > > > b/drivers/acpi/processor_driver.c > > > > index 0553aee..0e0b629 100644 > > > > --- a/drivers/acpi/processor_driver.c > > > > +++ b/drivers/acpi/processor_driver.c > > > > @@ -245,8 +245,11 @@ static int __acpi_processor_start(struct > > > > acpi_device *device) > > > >                 return 0; > > > > > > > >         result = acpi_cppc_processor_probe(pr); > > > > -       if (result) > > > > +       if (result) { > > > > +#ifndef CONFIG_ACPI_CPU_FREQ_PSS > > > >                 return -ENODEV; > > > > +#endif > > > > +       } > > > > > > > >         if (!cpuidle_get_driver() || cpuidle_get_driver() == > > > > &acpi_idle_driver) > > > >                 acpi_processor_power_init(pr); > > > > -- > > > > 2.7.4 > > > > > > > > -- > > > > To unsubscribe from this list: send the line "unsubscribe > > > > linux- > > > > acpi" in > > > > the body of a message to majordomo@vger.kernel.org > > > > More majordomo info at  http://vger.kernel.org/majordomo-info.h > > > > tml > > > -- > > > To unsubscribe from this list: send the line "unsubscribe linux- > > > pm" > > > in > > > the body of a message to majordomo@vger.kernel.org > > > More majordomo info at  http://vger.kernel.org/majordomo-info.htm > > > l > -- > To unsubscribe from this list: send the line "unsubscribe linux-pm" > in > the body of a message to majordomo@vger.kernel.org > More majordomo info at  http://vger.kernel.org/majordomo-info.html