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Message-ID: <78494d57-40cf-4604-b1b6-8d94ca1c9973@amd.com>
Date: Tue, 2 Jan 2024 13:52:27 -0600
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Reply-To: babu.moger@amd.com
Subject: Re: [PATCH v2 1/2] x86/resctrl: Remove hard-coded memory bandwidth
 limit
To: Reinette Chatre <reinette.chatre@intel.com>, corbet@lwn.net,
 fenghua.yu@intel.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
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From: "Moger, Babu" <babu.moger@amd.com>
In-Reply-To: <70b27d47-fdd8-46e3-a5d8-6bd9c1ca95fe@intel.com>
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Hi Reinette,

On 12/14/23 20:20, Reinette Chatre wrote:
> 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@amd.com>
>>
>> ---
> 
> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>

Thank You
Babu Moger