[PATCH v6 1/6] ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors

Perry Yuan posted 6 patches 1 year, 10 months ago
There is a newer version of this series
[PATCH v6 1/6] ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors
Posted by Perry Yuan 1 year, 10 months ago
As there are some AMD processors which only support CPPC V2 firmware and
BIOS implementation, the amd_pstate driver will be failed to load when
system booting with below kernel warning message:

[    0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled

To make the amd_pstate driver can be loaded on those TR40 processors, it
needs to match x86_model from 0x30 to 0x7F for family 17H.
With the change, the system can load amd_pstate driver as expected.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reported-by: Gino Badouri <badouri.g@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218171
Fixes: fbd74d1689 ("ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory")
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
---
 arch/x86/kernel/acpi/cppc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/acpi/cppc.c b/arch/x86/kernel/acpi/cppc.c
index 8d8752b44f11..ff8f25faca3d 100644
--- a/arch/x86/kernel/acpi/cppc.c
+++ b/arch/x86/kernel/acpi/cppc.c
@@ -20,7 +20,7 @@ bool cpc_supported_by_cpu(void)
 		    (boot_cpu_data.x86_model >= 0x20 && boot_cpu_data.x86_model <= 0x2f)))
 			return true;
 		else if (boot_cpu_data.x86 == 0x17 &&
-			 boot_cpu_data.x86_model >= 0x70 && boot_cpu_data.x86_model <= 0x7f)
+			 boot_cpu_data.x86_model >= 0x30 && boot_cpu_data.x86_model <= 0x7f)
 			return true;
 		return boot_cpu_has(X86_FEATURE_CPPC);
 	}
-- 
2.34.1
Re: [PATCH v6 1/6] ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors
Posted by Gautham R. Shenoy 1 year, 10 months ago
Hello Perry,

On Thu, Feb 08, 2024 at 11:46:28AM +0800, Perry Yuan wrote:
> As there are some AMD processors which only support CPPC V2 firmware and
> BIOS implementation, the amd_pstate driver will be failed to load when
> system booting with below kernel warning message:
> 
> [    0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled
> 
> To make the amd_pstate driver can be loaded on those TR40 processors, it
> needs to match x86_model from 0x30 to 0x7F for family 17H.
> With the change, the system can load amd_pstate driver as expected.
> 
> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
> Reported-by: Gino Badouri <badouri.g@gmail.com>
> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218171
> Fixes: fbd74d1689 ("ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory")
> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
> ---
>  arch/x86/kernel/acpi/cppc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/acpi/cppc.c b/arch/x86/kernel/acpi/cppc.c
> index 8d8752b44f11..ff8f25faca3d 100644
> --- a/arch/x86/kernel/acpi/cppc.c
> +++ b/arch/x86/kernel/acpi/cppc.c
> @@ -20,7 +20,7 @@ bool cpc_supported_by_cpu(void)
>  		    (boot_cpu_data.x86_model >= 0x20 && boot_cpu_data.x86_model <= 0x2f)))
>  			return true;
>  		else if (boot_cpu_data.x86 == 0x17 &&
> -			 boot_cpu_data.x86_model >= 0x70 && boot_cpu_data.x86_model <= 0x7f)
> +			 boot_cpu_data.x86_model >= 0x30 && boot_cpu_data.x86_model <= 0x7f)

This looks ok to me.
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>

--
Thanks and Regards
gautham.
Re: [PATCH v6 1/6] ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors
Posted by Rafael J. Wysocki 1 year, 9 months ago
On Thu, Feb 8, 2024 at 6:56 AM Gautham R. Shenoy <gautham.shenoy@amd.com> wrote:
>
> Hello Perry,
>
> On Thu, Feb 08, 2024 at 11:46:28AM +0800, Perry Yuan wrote:
> > As there are some AMD processors which only support CPPC V2 firmware and
> > BIOS implementation, the amd_pstate driver will be failed to load when
> > system booting with below kernel warning message:
> >
> > [    0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled
> >
> > To make the amd_pstate driver can be loaded on those TR40 processors, it
> > needs to match x86_model from 0x30 to 0x7F for family 17H.
> > With the change, the system can load amd_pstate driver as expected.
> >
> > Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
> > Reported-by: Gino Badouri <badouri.g@gmail.com>
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218171
> > Fixes: fbd74d1689 ("ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory")
> > Signed-off-by: Perry Yuan <perry.yuan@amd.com>
> > ---
> >  arch/x86/kernel/acpi/cppc.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/kernel/acpi/cppc.c b/arch/x86/kernel/acpi/cppc.c
> > index 8d8752b44f11..ff8f25faca3d 100644
> > --- a/arch/x86/kernel/acpi/cppc.c
> > +++ b/arch/x86/kernel/acpi/cppc.c
> > @@ -20,7 +20,7 @@ bool cpc_supported_by_cpu(void)
> >                   (boot_cpu_data.x86_model >= 0x20 && boot_cpu_data.x86_model <= 0x2f)))
> >                       return true;
> >               else if (boot_cpu_data.x86 == 0x17 &&
> > -                      boot_cpu_data.x86_model >= 0x70 && boot_cpu_data.x86_model <= 0x7f)
> > +                      boot_cpu_data.x86_model >= 0x30 && boot_cpu_data.x86_model <= 0x7f)
>
> This looks ok to me.
> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>

Applied as 6.9 material, thanks!

However, I'm not sure what to do with the rest of the series.  It
doesn't appear to be ready yet as they are comments that need
addressing AFAICS.