| Message ID | 1416299826-15813-8-git-send-email-ethan.zhao@oracle.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tue, 18 Nov 2014 17:37:06 +0900 Ethan Zhao <ethan.zhao@oracle.com> wrote: > Add kernel command line parameter > intel_pstate = ignore_acpi_ppc > and module parameter > ignore_acpi_ppc = 1 > to allow driver to ignore the ACPI _PPC existence even for Sun x86 servers. > These parameter could be used for debug\test\workaround etc purpose. > > Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> What if we used a more generic parameter like "force" that would bypass any vendor specific checks and just load anyway? This way we don't have to add new parameters everything some new thing shows up that we want to ignore. > --- > Documentation/kernel-parameters.txt | 3 +++ > drivers/cpufreq/intel_pstate.c | 8 +++++++- > 2 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 4c81a86..f502b85 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > disable > Do not enable intel_pstate as the default > scaling driver for the supported processors > + ignore_acpi_ppc > + Ignore the existence of ACPI method _PPC for Sun x86 servers > + and load the driver. > > intremap= [X86-64, Intel-IOMMU] > on enable Interrupt Remapping (default) > diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > index 7c5faea..388387b 100644 > --- a/drivers/cpufreq/intel_pstate.c > +++ b/drivers/cpufreq/intel_pstate.c > @@ -870,6 +870,7 @@ static struct cpufreq_driver intel_pstate_driver = { > }; > > static int __initdata no_load; > +static unsigned int ignore_acpi_ppc; > > static int intel_pstate_msrs_not_valid(void) > { > @@ -990,7 +991,7 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) > intel_pstate_no_acpi_pss()) > return true; > if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) && > - intel_pstate_has_acpi_ppc()) > + intel_pstate_has_acpi_ppc() && !ignore_acpi_ppc) > return true; > } > > @@ -1066,11 +1067,16 @@ static int __init intel_pstate_setup(char *str) > > if (!strcmp(str, "disable")) > no_load = 1; > + if (!strcmp(str, "ignore_acpi_ppc")) > + ignore_acpi_ppc = 1; > return 0; > } > early_param("intel_pstate", intel_pstate_setup); > #endif > > +module_param(ignore_acpi_ppc, uint, 0644); > +MODULE_PARM_DESC(ignore_acpi_ppc, > + "value 0 or non-zero. non-zero -> ignore ACPI _PPC and load this driver"); > MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); > MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); > MODULE_LICENSE("GPL"); -- 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
> ? 2014?11?20??03:05?Kristen Carlson Accardi <kristen@linux.intel.com> ??? > > On Tue, 18 Nov 2014 17:37:06 +0900 > Ethan Zhao <ethan.zhao@oracle.com> wrote: > >> Add kernel command line parameter >> intel_pstate = ignore_acpi_ppc >> and module parameter >> ignore_acpi_ppc = 1 >> to allow driver to ignore the ACPI _PPC existence even for Sun x86 servers. >> These parameter could be used for debug\test\workaround etc purpose. >> >> Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> > > What if we used a more generic parameter like "force" that would bypass > any vendor specific checks and just load anyway? This way we don't have > to add new parameters everything some new thing shows up that we want to > ignore. > To be honest, I prefer more generic parameter. But to avoid the possible negative affect To another vendors. I back to this way. Thanks, Ethan >> --- >> Documentation/kernel-parameters.txt | 3 +++ >> drivers/cpufreq/intel_pstate.c | 8 +++++++- >> 2 files changed, 10 insertions(+), 1 deletion(-) >> >> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >> index 4c81a86..f502b85 100644 >> --- a/Documentation/kernel-parameters.txt >> +++ b/Documentation/kernel-parameters.txt >> @@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. >> disable >> Do not enable intel_pstate as the default >> scaling driver for the supported processors >> + ignore_acpi_ppc >> + Ignore the existence of ACPI method _PPC for Sun x86 servers >> + and load the driver. >> >> intremap= [X86-64, Intel-IOMMU] >> on enable Interrupt Remapping (default) >> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c >> index 7c5faea..388387b 100644 >> --- a/drivers/cpufreq/intel_pstate.c >> +++ b/drivers/cpufreq/intel_pstate.c >> @@ -870,6 +870,7 @@ static struct cpufreq_driver intel_pstate_driver = { >> }; >> >> static int __initdata no_load; >> +static unsigned int ignore_acpi_ppc; >> >> static int intel_pstate_msrs_not_valid(void) >> { >> @@ -990,7 +991,7 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) >> intel_pstate_no_acpi_pss()) >> return true; >> if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) && >> - intel_pstate_has_acpi_ppc()) >> + intel_pstate_has_acpi_ppc() && !ignore_acpi_ppc) >> return true; >> } >> >> @@ -1066,11 +1067,16 @@ static int __init intel_pstate_setup(char *str) >> >> if (!strcmp(str, "disable")) >> no_load = 1; >> + if (!strcmp(str, "ignore_acpi_ppc")) >> + ignore_acpi_ppc = 1; >> return 0; >> } >> early_param("intel_pstate", intel_pstate_setup); >> #endif >> >> +module_param(ignore_acpi_ppc, uint, 0644); >> +MODULE_PARM_DESC(ignore_acpi_ppc, >> + "value 0 or non-zero. non-zero -> ignore ACPI _PPC and load this driver"); >> MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); >> MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); >> MODULE_LICENSE("GPL"); > -- 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
On Thu, 20 Nov 2014 08:57:34 +0800 ethan <ethan.kernel@gmail.com> wrote: > > > > ? 2014?11?20??03:05?Kristen Carlson Accardi <kristen@linux.intel.com> ??? > > > > On Tue, 18 Nov 2014 17:37:06 +0900 > > Ethan Zhao <ethan.zhao@oracle.com> wrote: > > > >> Add kernel command line parameter > >> intel_pstate = ignore_acpi_ppc > >> and module parameter > >> ignore_acpi_ppc = 1 > >> to allow driver to ignore the ACPI _PPC existence even for Sun x86 servers. > >> These parameter could be used for debug\test\workaround etc purpose. > >> > >> Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> > > > > What if we used a more generic parameter like "force" that would bypass > > any vendor specific checks and just load anyway? This way we don't have > > to add new parameters everything some new thing shows up that we want to > > ignore. > > > To be honest, I prefer more generic parameter. But to avoid the possible negative affect > To another vendors. I back to this way. Well, your parameter can still impact other vendors as it is. it is pretty typical to assume that using a parameter like "force" means you know what you are doing and accept the risks. Especially if its documented as such. > > Thanks, > Ethan > >> --- > >> Documentation/kernel-parameters.txt | 3 +++ > >> drivers/cpufreq/intel_pstate.c | 8 +++++++- > >> 2 files changed, 10 insertions(+), 1 deletion(-) > >> > >> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > >> index 4c81a86..f502b85 100644 > >> --- a/Documentation/kernel-parameters.txt > >> +++ b/Documentation/kernel-parameters.txt > >> @@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > >> disable > >> Do not enable intel_pstate as the default > >> scaling driver for the supported processors > >> + ignore_acpi_ppc > >> + Ignore the existence of ACPI method _PPC for Sun x86 servers > >> + and load the driver. > >> > >> intremap= [X86-64, Intel-IOMMU] > >> on enable Interrupt Remapping (default) > >> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > >> index 7c5faea..388387b 100644 > >> --- a/drivers/cpufreq/intel_pstate.c > >> +++ b/drivers/cpufreq/intel_pstate.c > >> @@ -870,6 +870,7 @@ static struct cpufreq_driver intel_pstate_driver = { > >> }; > >> > >> static int __initdata no_load; > >> +static unsigned int ignore_acpi_ppc; > >> > >> static int intel_pstate_msrs_not_valid(void) > >> { > >> @@ -990,7 +991,7 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) > >> intel_pstate_no_acpi_pss()) > >> return true; > >> if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) && > >> - intel_pstate_has_acpi_ppc()) > >> + intel_pstate_has_acpi_ppc() && !ignore_acpi_ppc) > >> return true; > >> } > >> > >> @@ -1066,11 +1067,16 @@ static int __init intel_pstate_setup(char *str) > >> > >> if (!strcmp(str, "disable")) > >> no_load = 1; > >> + if (!strcmp(str, "ignore_acpi_ppc")) > >> + ignore_acpi_ppc = 1; > >> return 0; > >> } > >> early_param("intel_pstate", intel_pstate_setup); > >> #endif > >> > >> +module_param(ignore_acpi_ppc, uint, 0644); > >> +MODULE_PARM_DESC(ignore_acpi_ppc, > >> + "value 0 or non-zero. non-zero -> ignore ACPI _PPC and load this driver"); > >> MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); > >> MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); > >> MODULE_LICENSE("GPL"); > > -- 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
Kristen, Whatever I would like there is a way to load intel_pstate and give it a try even it does not support all the PM features. I think 'force' is OK. Linda, Do you like it ? if the 'intel_pstate=force' would force the driver to be loaded on to HP too ? Thanks, Ethan On Fri, Nov 21, 2014 at 5:23 AM, Kristen Carlson Accardi <kristen@linux.intel.com> wrote: > On Thu, 20 Nov 2014 08:57:34 +0800 > ethan <ethan.kernel@gmail.com> wrote: > >> >> >> > ? 2014?11?20??03:05?Kristen Carlson Accardi <kristen@linux.intel.com> ??? >> > >> > On Tue, 18 Nov 2014 17:37:06 +0900 >> > Ethan Zhao <ethan.zhao@oracle.com> wrote: >> > >> >> Add kernel command line parameter >> >> intel_pstate = ignore_acpi_ppc >> >> and module parameter >> >> ignore_acpi_ppc = 1 >> >> to allow driver to ignore the ACPI _PPC existence even for Sun x86 servers. >> >> These parameter could be used for debug\test\workaround etc purpose. >> >> >> >> Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> >> > >> > What if we used a more generic parameter like "force" that would bypass >> > any vendor specific checks and just load anyway? This way we don't have >> > to add new parameters everything some new thing shows up that we want to >> > ignore. >> > >> To be honest, I prefer more generic parameter. But to avoid the possible negative affect >> To another vendors. I back to this way. > > Well, your parameter can still impact other vendors as it is. it > is pretty typical to assume that using a parameter like "force" means > you know what you are doing and accept the risks. Especially if its > documented as such. > >> >> Thanks, >> Ethan >> >> --- >> >> Documentation/kernel-parameters.txt | 3 +++ >> >> drivers/cpufreq/intel_pstate.c | 8 +++++++- >> >> 2 files changed, 10 insertions(+), 1 deletion(-) >> >> >> >> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >> >> index 4c81a86..f502b85 100644 >> >> --- a/Documentation/kernel-parameters.txt >> >> +++ b/Documentation/kernel-parameters.txt >> >> @@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. >> >> disable >> >> Do not enable intel_pstate as the default >> >> scaling driver for the supported processors >> >> + ignore_acpi_ppc >> >> + Ignore the existence of ACPI method _PPC for Sun x86 servers >> >> + and load the driver. >> >> >> >> intremap= [X86-64, Intel-IOMMU] >> >> on enable Interrupt Remapping (default) >> >> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c >> >> index 7c5faea..388387b 100644 >> >> --- a/drivers/cpufreq/intel_pstate.c >> >> +++ b/drivers/cpufreq/intel_pstate.c >> >> @@ -870,6 +870,7 @@ static struct cpufreq_driver intel_pstate_driver = { >> >> }; >> >> >> >> static int __initdata no_load; >> >> +static unsigned int ignore_acpi_ppc; >> >> >> >> static int intel_pstate_msrs_not_valid(void) >> >> { >> >> @@ -990,7 +991,7 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) >> >> intel_pstate_no_acpi_pss()) >> >> return true; >> >> if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) && >> >> - intel_pstate_has_acpi_ppc()) >> >> + intel_pstate_has_acpi_ppc() && !ignore_acpi_ppc) >> >> return true; >> >> } >> >> >> >> @@ -1066,11 +1067,16 @@ static int __init intel_pstate_setup(char *str) >> >> >> >> if (!strcmp(str, "disable")) >> >> no_load = 1; >> >> + if (!strcmp(str, "ignore_acpi_ppc")) >> >> + ignore_acpi_ppc = 1; >> >> return 0; >> >> } >> >> early_param("intel_pstate", intel_pstate_setup); >> >> #endif >> >> >> >> +module_param(ignore_acpi_ppc, uint, 0644); >> >> +MODULE_PARM_DESC(ignore_acpi_ppc, >> >> + "value 0 or non-zero. non-zero -> ignore ACPI _PPC and load this driver"); >> >> MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); >> >> MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); >> >> MODULE_LICENSE("GPL"); >> > > -- 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
On 11/20/2014 10:07 PM, Ethan Zhao wrote: > Kristen, > Whatever I would like there is a way to load intel_pstate and give > it a try even it does not support all the PM features. > I think 'force' is OK. > Linda, > Do you like it ? if the 'intel_pstate=force' would force the driver > to be loaded on to HP too ? I'd prefer that it didn't. If you force the intel_pstate driver when the platform thinks it's doing power management, then the OS and the firmware are trying to manage the power at the same time. That's a mess. If you want that for testing or debugging, what are you actually testing or debugging? On an Oracle box, the firmware wouldn't stop doing whatever it's doing just because the intel_pstate driver is loaded, would it? I also wonder what it means to "force" the intel_pstate driver on systems with processors that aren't supported by the intel_pstate driver. It wouldn't really be forced, would it? -- ljk > > Thanks, > Ethan > > On Fri, Nov 21, 2014 at 5:23 AM, Kristen Carlson Accardi > <kristen@linux.intel.com> wrote: >> On Thu, 20 Nov 2014 08:57:34 +0800 >> ethan <ethan.kernel@gmail.com> wrote: >> >>> >>> >>>> ? 2014?11?20??03:05?Kristen Carlson Accardi <kristen@linux.intel.com> ??? >>>> >>>> On Tue, 18 Nov 2014 17:37:06 +0900 >>>> Ethan Zhao <ethan.zhao@oracle.com> wrote: >>>> >>>>> Add kernel command line parameter >>>>> intel_pstate = ignore_acpi_ppc >>>>> and module parameter >>>>> ignore_acpi_ppc = 1 >>>>> to allow driver to ignore the ACPI _PPC existence even for Sun x86 servers. >>>>> These parameter could be used for debug\test\workaround etc purpose. >>>>> >>>>> Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> >>>> >>>> What if we used a more generic parameter like "force" that would bypass >>>> any vendor specific checks and just load anyway? This way we don't have >>>> to add new parameters everything some new thing shows up that we want to >>>> ignore. >>>> >>> To be honest, I prefer more generic parameter. But to avoid the possible negative affect >>> To another vendors. I back to this way. >> >> Well, your parameter can still impact other vendors as it is. it >> is pretty typical to assume that using a parameter like "force" means >> you know what you are doing and accept the risks. Especially if its >> documented as such. >> >>> >>> Thanks, >>> Ethan >>>>> --- >>>>> Documentation/kernel-parameters.txt | 3 +++ >>>>> drivers/cpufreq/intel_pstate.c | 8 +++++++- >>>>> 2 files changed, 10 insertions(+), 1 deletion(-) >>>>> >>>>> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >>>>> index 4c81a86..f502b85 100644 >>>>> --- a/Documentation/kernel-parameters.txt >>>>> +++ b/Documentation/kernel-parameters.txt >>>>> @@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. >>>>> disable >>>>> Do not enable intel_pstate as the default >>>>> scaling driver for the supported processors >>>>> + ignore_acpi_ppc >>>>> + Ignore the existence of ACPI method _PPC for Sun x86 servers >>>>> + and load the driver. >>>>> >>>>> intremap= [X86-64, Intel-IOMMU] >>>>> on enable Interrupt Remapping (default) >>>>> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c >>>>> index 7c5faea..388387b 100644 >>>>> --- a/drivers/cpufreq/intel_pstate.c >>>>> +++ b/drivers/cpufreq/intel_pstate.c >>>>> @@ -870,6 +870,7 @@ static struct cpufreq_driver intel_pstate_driver = { >>>>> }; >>>>> >>>>> static int __initdata no_load; >>>>> +static unsigned int ignore_acpi_ppc; >>>>> >>>>> static int intel_pstate_msrs_not_valid(void) >>>>> { >>>>> @@ -990,7 +991,7 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) >>>>> intel_pstate_no_acpi_pss()) >>>>> return true; >>>>> if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) && >>>>> - intel_pstate_has_acpi_ppc()) >>>>> + intel_pstate_has_acpi_ppc() && !ignore_acpi_ppc) >>>>> return true; >>>>> } >>>>> >>>>> @@ -1066,11 +1067,16 @@ static int __init intel_pstate_setup(char *str) >>>>> >>>>> if (!strcmp(str, "disable")) >>>>> no_load = 1; >>>>> + if (!strcmp(str, "ignore_acpi_ppc")) >>>>> + ignore_acpi_ppc = 1; >>>>> return 0; >>>>> } >>>>> early_param("intel_pstate", intel_pstate_setup); >>>>> #endif >>>>> >>>>> +module_param(ignore_acpi_ppc, uint, 0644); >>>>> +MODULE_PARM_DESC(ignore_acpi_ppc, >>>>> + "value 0 or non-zero. non-zero -> ignore ACPI _PPC and load this driver"); >>>>> MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); >>>>> MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); >>>>> MODULE_LICENSE("GPL"); >>>> >> > -- > 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 > -- 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
Linda, On 2014/11/21 13:00, Linda Knippers wrote: > > On 11/20/2014 10:07 PM, Ethan Zhao wrote: >> Kristen, >> Whatever I would like there is a way to load intel_pstate and give >> it a try even it does not support all the PM features. >> I think 'force' is OK. >> Linda, >> Do you like it ? if the 'intel_pstate=force' would force the driver >> to be loaded on to HP too ? > I'd prefer that it didn't. If you force the intel_pstate driver when > the platform thinks it's doing power management, then the OS and the > firmware are trying to manage the power at the same time. That's a > mess. If you want that for testing or debugging, what are you actually > testing or debugging? On an Oracle box, the firmware wouldn't stop > doing whatever it's doing just because the intel_pstate driver is > loaded, would it? Yes, the platform wouldn't stop doing PM and the SCI even the intel_pstate was loaded. That option just give someone a chance who said "whatever I like intel_pstate On Oracle Servers" > > I also wonder what it means to "force" the intel_pstate driver > on systems with processors that aren't supported by the intel_pstate > driver. It wouldn't really be forced, would it? Yes, wouldn't, such as AMD cpu-id and some old intel CPUs released before SandyBridge. So the best way to to do the 'force' should be specific enough for "Oracle Sun server" Thanks, Ethan > > -- ljk > >> Thanks, >> Ethan >> >> On Fri, Nov 21, 2014 at 5:23 AM, Kristen Carlson Accardi >> <kristen@linux.intel.com> wrote: >>> On Thu, 20 Nov 2014 08:57:34 +0800 >>> ethan <ethan.kernel@gmail.com> wrote: >>> >>>> >>>>> ? 2014?11?20??03:05?Kristen Carlson Accardi <kristen@linux.intel.com> ??? >>>>> >>>>> On Tue, 18 Nov 2014 17:37:06 +0900 >>>>> Ethan Zhao <ethan.zhao@oracle.com> wrote: >>>>> >>>>>> Add kernel command line parameter >>>>>> intel_pstate = ignore_acpi_ppc >>>>>> and module parameter >>>>>> ignore_acpi_ppc = 1 >>>>>> to allow driver to ignore the ACPI _PPC existence even for Sun x86 servers. >>>>>> These parameter could be used for debug\test\workaround etc purpose. >>>>>> >>>>>> Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> >>>>> What if we used a more generic parameter like "force" that would bypass >>>>> any vendor specific checks and just load anyway? This way we don't have >>>>> to add new parameters everything some new thing shows up that we want to >>>>> ignore. >>>>> >>>> To be honest, I prefer more generic parameter. But to avoid the possible negative affect >>>> To another vendors. I back to this way. >>> Well, your parameter can still impact other vendors as it is. it >>> is pretty typical to assume that using a parameter like "force" means >>> you know what you are doing and accept the risks. Especially if its >>> documented as such. >>> >>>> Thanks, >>>> Ethan >>>>>> --- >>>>>> Documentation/kernel-parameters.txt | 3 +++ >>>>>> drivers/cpufreq/intel_pstate.c | 8 +++++++- >>>>>> 2 files changed, 10 insertions(+), 1 deletion(-) >>>>>> >>>>>> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >>>>>> index 4c81a86..f502b85 100644 >>>>>> --- a/Documentation/kernel-parameters.txt >>>>>> +++ b/Documentation/kernel-parameters.txt >>>>>> @@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. >>>>>> disable >>>>>> Do not enable intel_pstate as the default >>>>>> scaling driver for the supported processors >>>>>> + ignore_acpi_ppc >>>>>> + Ignore the existence of ACPI method _PPC for Sun x86 servers >>>>>> + and load the driver. >>>>>> >>>>>> intremap= [X86-64, Intel-IOMMU] >>>>>> on enable Interrupt Remapping (default) >>>>>> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c >>>>>> index 7c5faea..388387b 100644 >>>>>> --- a/drivers/cpufreq/intel_pstate.c >>>>>> +++ b/drivers/cpufreq/intel_pstate.c >>>>>> @@ -870,6 +870,7 @@ static struct cpufreq_driver intel_pstate_driver = { >>>>>> }; >>>>>> >>>>>> static int __initdata no_load; >>>>>> +static unsigned int ignore_acpi_ppc; >>>>>> >>>>>> static int intel_pstate_msrs_not_valid(void) >>>>>> { >>>>>> @@ -990,7 +991,7 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) >>>>>> intel_pstate_no_acpi_pss()) >>>>>> return true; >>>>>> if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) && >>>>>> - intel_pstate_has_acpi_ppc()) >>>>>> + intel_pstate_has_acpi_ppc() && !ignore_acpi_ppc) >>>>>> return true; >>>>>> } >>>>>> >>>>>> @@ -1066,11 +1067,16 @@ static int __init intel_pstate_setup(char *str) >>>>>> >>>>>> if (!strcmp(str, "disable")) >>>>>> no_load = 1; >>>>>> + if (!strcmp(str, "ignore_acpi_ppc")) >>>>>> + ignore_acpi_ppc = 1; >>>>>> return 0; >>>>>> } >>>>>> early_param("intel_pstate", intel_pstate_setup); >>>>>> #endif >>>>>> >>>>>> +module_param(ignore_acpi_ppc, uint, 0644); >>>>>> +MODULE_PARM_DESC(ignore_acpi_ppc, >>>>>> + "value 0 or non-zero. non-zero -> ignore ACPI _PPC and load this driver"); >>>>>> MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); >>>>>> MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); >>>>>> MODULE_LICENSE("GPL"); >> -- >> 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 >> -- 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
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 4c81a86..f502b85 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. disable Do not enable intel_pstate as the default scaling driver for the supported processors + ignore_acpi_ppc + Ignore the existence of ACPI method _PPC for Sun x86 servers + and load the driver. intremap= [X86-64, Intel-IOMMU] on enable Interrupt Remapping (default) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 7c5faea..388387b 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -870,6 +870,7 @@ static struct cpufreq_driver intel_pstate_driver = { }; static int __initdata no_load; +static unsigned int ignore_acpi_ppc; static int intel_pstate_msrs_not_valid(void) { @@ -990,7 +991,7 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) intel_pstate_no_acpi_pss()) return true; if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) && - intel_pstate_has_acpi_ppc()) + intel_pstate_has_acpi_ppc() && !ignore_acpi_ppc) return true; } @@ -1066,11 +1067,16 @@ static int __init intel_pstate_setup(char *str) if (!strcmp(str, "disable")) no_load = 1; + if (!strcmp(str, "ignore_acpi_ppc")) + ignore_acpi_ppc = 1; return 0; } early_param("intel_pstate", intel_pstate_setup); #endif +module_param(ignore_acpi_ppc, uint, 0644); +MODULE_PARM_DESC(ignore_acpi_ppc, + "value 0 or non-zero. non-zero -> ignore ACPI _PPC and load this driver"); MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>"); MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors"); MODULE_LICENSE("GPL");
Add kernel command line parameter intel_pstate = ignore_acpi_ppc and module parameter ignore_acpi_ppc = 1 to allow driver to ignore the ACPI _PPC existence even for Sun x86 servers. These parameter could be used for debug\test\workaround etc purpose. Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> --- Documentation/kernel-parameters.txt | 3 +++ drivers/cpufreq/intel_pstate.c | 8 +++++++- 2 files changed, 10 insertions(+), 1 deletion(-)