Re: [PATCH v2 1/2] x86/resctrl: Remove hard-coded memory bandwidth limit

From: Reinette Chatre
Date: Thu Dec 14 2023 - 21:21:14 EST


Hi Babu,

On 12/12/2023 10:02 AM, Babu Moger wrote:
> The QOS Memory Bandwidth Enforcement Limit is reported by
> CPUID_Fn80000020_EAX_x01 and CPUID_Fn80000020_EAX_x02.
> Bits Description
> 31:0 BW_LEN: Size of the QOS Memory Bandwidth Enforcement Limit.
>
> Newer processors can support higher bandwidth limit than the current
> hard-coded value. Remove the hard-coded value and detect using CPUID
> command. Also update the register variables eax and edx to match the
> AMD CPUID definition.
>
> The CPUID details are documentation in the PPR listed below [1].
> [1] Processor Programming Reference (PPR) Vol 1.1 for AMD Family 19h Model
> 11h B1 - 55901 Rev 0.25.
>
> Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature")
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
>
> ---

Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>

Reinette