Messages in this thread | | | From | "Michael S. Zick" <> | Subject | Re: [PATCH 1/2] CPUFREQ: Enable acpi-cpufreq driver for VIA/Centaur CPUs | Date | Mon, 8 Jun 2009 15:03:28 -0500 |
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On Mon June 8 2009, Harald Welte wrote: > The VIA/Centaur C7, C7-M and Nano CPU's all support ACPI based cpu p-states > using a MSR interface. The Linux driver just never made use of it, since in > addition to the check for the EST flag it also checked if the vendor is Intel. > > Signed-off-by: Harald Welte <HaraldWelte@viatech.com> > --- > arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c > index 208ecf6..ee03585 100644 > --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c > +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c > @@ -90,7 +90,8 @@ static int check_est_cpu(unsigned int cpuid) > { > struct cpuinfo_x86 *cpu = &cpu_data(cpuid); > > - if (cpu->x86_vendor != X86_VENDOR_INTEL || > + if ((cpu->x86_vendor != X86_VENDOR_INTEL && > + cpu->x86_vendor != X86_VENDOR_CENTAUR) || > !cpu_has(cpu, X86_FEATURE_EST)) > return 0; >
For my own internal testing, based on subsequent posts, I simplified that to:
static int check_est_cpu(unsigned int cpuid) { struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
if (!cpu_has(cpu, X86_FEATURE_EST)) return 0;
return 1; }
Have not done anything (yet) to deal with the adaptive controller, **which is safe to (not) do on my test system because I know it isn't enabled**
Note: This machine is known to run common, proprietary operating systems, so I am also assuming its BIOS ACPI is complete enough.
Note 2: Don't try this unless you have a machine to waste. ;)
Mike
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