From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754839AbdFWS7e (ORCPT ); Fri, 23 Jun 2017 14:59:34 -0400 Received: from gloria.sntech.de ([95.129.55.99]:41474 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754327AbdFWS7d (ORCPT ); Fri, 23 Jun 2017 14:59:33 -0400 From: Heiko Stuebner To: Brian Norris Cc: linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Caesar Wang , Doug Anderson , linux-arm-kernel@lists.infradead.org, Matthias Kaehlcke Subject: Re: [PATCH 3/3] arm64: dts: rockchip: set rk3399 dynamic CPU power coefficients Date: Fri, 23 Jun 2017 20:59:29 +0200 Message-ID: <2934827.QH3zHdFam1@phil> User-Agent: KMail/5.2.3 (Linux/4.9.0-2-amd64; KDE/5.28.0; x86_64; ; ) In-Reply-To: <20170623184956.GA107165@google.com> References: <20170623170737.46265-1-briannorris@chromium.org> <5395662.EDQ3y7Qj0C@phil> <20170623184956.GA107165@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Freitag, 23. Juni 2017, 11:49:57 CEST schrieb Brian Norris: > On Fri, Jun 23, 2017 at 08:39:25PM +0200, Heiko Stuebner wrote: > > Am Freitag, 23. Juni 2017, 10:07:37 CEST schrieb Brian Norris: > > > Provide the dynamic power coefficient of the big and little CPU > > > clusters. These numbers are currently in use on the Samsung Chromebook > > > Plus ("Kevin"). > > > > > > The power allocator thermal governor doesn't know how to do anything if > > > it doesn't get power parameters from its cooling devices (in this case, > > > CPUfreq). So this effectively enables the power-allocator governor. > > > > > > Signed-off-by: Brian Norris > > > --- > > > arch/arm64/boot/dts/rockchip/rk3399.dtsi | 2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi > > > index 69c56f7316c4..4f6667547814 100644 > > > --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi > > > +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi > > > @@ -109,6 +109,7 @@ > > > reg = <0x0 0x0>; > > > enable-method = "psci"; > > > #cooling-cells = <2>; /* min followed by max */ > > > + dynamic-power-coefficient = <100>; > > > clocks = <&cru ARMCLKL>; > > > }; > > > > > > @@ -142,6 +143,7 @@ > > > reg = <0x0 0x100>; > > > enable-method = "psci"; > > > #cooling-cells = <2>; /* min followed by max */ > > > + dynamic-power-coefficient = <100>; > > > clocks = <&cru ARMCLKB>; > > > }; > > > > > > > > > > I think these should be set for all cores, similar to clocks. While > > cpufreq and friends regularly only take the first number, in a > > hw-description sense, it should be part of every core in the dt. > > It's kinda paired with the cooling information (e.g., #cooling-cells) > which are only present in the first CPU in the cluster, currently. > > I can copy this definitely real, empirical value into the other CPUs if > you really think that's necessary :) I just remember that has come up in the past for other cpu properties. dynamic-power-coefficient is defined in the general arm cpu binding, similar to clocks. And who knows, that value might not stay tied to only thermal in the future, so I think they should be in all cores. But you know what, I can duplicate this myself as well when applying :-) . Heiko