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Message-ID: <70b27d47-fdd8-46e3-a5d8-6bd9c1ca95fe@intel.com>
Date: Thu, 14 Dec 2023 18:20:56 -0800
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Subject: Re: [PATCH v2 1/2] x86/resctrl: Remove hard-coded memory bandwidth
 limit
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To: Babu Moger <babu.moger@amd.com>, <corbet@lwn.net>, <fenghua.yu@intel.com>,
	<tglx@linutronix.de>, <mingo@redhat.com>, <bp@alien8.de>,
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CC: <x86@kernel.org>, <hpa@zytor.com>, <paulmck@kernel.org>,
	<rdunlap@infradead.org>, <tj@kernel.org>, <peterz@infradead.org>,
	<seanjc@google.com>, <kim.phillips@amd.com>, <jmattson@google.com>,
	<ilpo.jarvinen@linux.intel.com>, <jithu.joseph@intel.com>,
	<kan.liang@linux.intel.com>, <nikunj@amd.com>,
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	<rick.p.edgecombe@intel.com>, <rppt@kernel.org>,
	<maciej.wieczor-retman@intel.com>, <linux-doc@vger.kernel.org>,
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References: <20231201005720.235639-1-babu.moger@amd.com>
 <170240413801.760665.7930294172146734221.stgit@bmoger-ubuntu>
From: Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <170240413801.760665.7930294172146734221.stgit@bmoger-ubuntu>
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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>

Reinette