From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4953BEB64DB for ; Thu, 15 Jun 2023 08:56:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239697AbjFOI4f (ORCPT ); Thu, 15 Jun 2023 04:56:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41340 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230102AbjFOI4e (ORCPT ); Thu, 15 Jun 2023 04:56:34 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C846B1BDA; Thu, 15 Jun 2023 01:56:33 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BD3BF1FB; Thu, 15 Jun 2023 01:57:17 -0700 (PDT) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id F2C0A3F71E; Thu, 15 Jun 2023 01:56:31 -0700 (PDT) Date: Thu, 15 Jun 2023 09:56:29 +0100 From: Sudeep Holla To: Tushar Nimkar Cc: "Rafael J . Wysocki" , Daniel Lezcano , Ulf Hansson , linux-pm@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, quic_lsrao@quicinc.com, quic_mkshah@quicinc.com, Sudeep Holla , devicetree@vger.kernel.org Subject: Re: [PATCH 1/2] dt-bindings: arm: idle-states: Add idle-state-disabled property Message-ID: <20230615085629.b2aaumhq7yqhs5lf@bogus> References: <20230608085544.16211-1-quic_tnimkar@quicinc.com> <20230608085544.16211-2-quic_tnimkar@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230608085544.16211-2-quic_tnimkar@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Thu, Jun 08, 2023 at 02:25:42PM +0530, Tushar Nimkar wrote: > This change adds idle-state-disabled property using which certain or all > idle-states can be kept disabled during boot-up. Once boot-up is completed > same can be enabled using below command. > > echo N > /sys/devices/system/cpu/cpuX/cpuidle/stateX/disable > > Cc: devicetree@vger.kernel.org > Signed-off-by: Tushar Nimkar > --- > Documentation/devicetree/bindings/cpu/idle-states.yaml | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/Documentation/devicetree/bindings/cpu/idle-states.yaml b/Documentation/devicetree/bindings/cpu/idle-states.yaml > index b8cc826c9501..f999bc666bbd 100644 > --- a/Documentation/devicetree/bindings/cpu/idle-states.yaml > +++ b/Documentation/devicetree/bindings/cpu/idle-states.yaml > @@ -358,6 +358,13 @@ patternProperties: > systems entry-latency-us + exit-latency-us will exceed > wakeup-latency-us by this duration. > > + idle-state-disabled: > + description: | > + If present the idle state stays disabled. It can be enabled back from > + shell using below command. > + echo N > /sys/devices/system/cpu/cpuX/cpuidle/stateX/disable > + type: boolean > + This is clearly a policy and not a hardware or firmware feature to expose in the device tree. So NACK, why can't you load it modules if you don't want idle states in the boot. It is same as choosing any default governor or performance states, will you add those next ? It is simply policy not a feature/property to be exposed in the device tree. -- Regards, Sudeep