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Date: Thu, 8 May 2025 17:09:20 +0100
From: Leo Yan <leo.yan@arm.com>
To: Sudeep Holla <sudeep.holla@arm.com>
Cc: linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
	Lorenzo Pieralisi <lpieralisi@kernel.org>,
	Liviu Dudau <liviu.dudau@arm.com>
Subject: Re: [PATCH 1/3] arm64: dts: fvp: Add CPU idle states for Rev C model
Message-ID: <20250508160920.GF177796@e132581.arm.com>
References: <20250508103225.354925-1-sudeep.holla@arm.com>
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In-Reply-To: <20250508103225.354925-1-sudeep.holla@arm.com>

Hi Sudeep,

On Thu, May 08, 2025 at 11:32:23AM +0100, Sudeep Holla wrote:
> Add CPU idle state definitions to the FVP Rev C device tree to enable
> support for CPU lower power modes. This allows the system to properly
> enter low power states during idle. It is disabled by default as it is
> know to impact performance on the models.
> 
> Note that the power_state parameter(arm,psci-suspend-param) doesn't use
> the Extended StateID format for compatibility reasons on FVP.
> 
> Tested on the FVP Rev C model with PSCI support enabled firmware.

I verified this series and confirmed the CPUIdle states work well (I
manually removed the status = "disabled" in idle state nodes).

Tested-by: Leo Yan <leo.yan@arm.com>

Just a nitpick, we should firstly add the timer node and then add the
idle state nodes, as CPUIdle is dependent on broadcast timer.

As the idle states are disabled by default, current patch ordering
would be fine as well.

Thanks,
Leo