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Date: Mon, 28 Oct 2024 10:44:50 +0000
From: Sudeep Holla <sudeep.holla@arm.com>
To: David Dai <davidai@google.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Rob Herring <robh@kernel.org>, Sudeep Holla <sudeep.holla@arm.com>,
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	Conor Dooley <conor+dt@kernel.org>,
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	kernel-team@android.com, linux-pm@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v7 2/2] cpufreq: add virtual-cpufreq driver
Message-ID: <Zx9rIjen30ArZd6k@bogus>
References: <20240919000837.1004642-1-davidai@google.com>
 <20240919000837.1004642-3-davidai@google.com>
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In-Reply-To: <20240919000837.1004642-3-davidai@google.com>

On Wed, Sep 18, 2024 at 05:08:33PM -0700, David Dai wrote:
> Introduce a virtualized cpufreq driver for guest kernels to improve
> performance and power of workloads within VMs.
> 
> This driver does two main things:
> 
> 1. Sends the frequency of vCPUs as a hint to the host. The host uses the
> hint to schedule the vCPU threads and decide physical CPU frequency.
> 
> 2. If a VM does not support a virtualized FIE(like AMUs), it queries the
> host CPU frequency by reading a MMIO region of a virtual cpufreq device
> to update the guest's frequency scaling factor periodically. This enables
> accurate Per-Entity Load Tracking for tasks running in the guest.
>

Acked-by: Sudeep Holla <sudeep.holla@arm.com>

-- 
Regards,
Sudeep