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 40E14EB64DC for ; Fri, 21 Jul 2023 11:59:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230193AbjGUL7t (ORCPT ); Fri, 21 Jul 2023 07:59:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229453AbjGUL7s (ORCPT ); Fri, 21 Jul 2023 07:59:48 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 5DAB3171B; Fri, 21 Jul 2023 04:59:47 -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 7FB2C2F4; Fri, 21 Jul 2023 05:00:30 -0700 (PDT) Received: from bogus (unknown [10.57.96.100]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BD21C3F6C4; Fri, 21 Jul 2023 04:59:44 -0700 (PDT) Date: Fri, 21 Jul 2023 12:59:17 +0100 From: Sudeep Holla To: Ulf Hansson Cc: Cristian Marussi , Viresh Kumar , Nishanth Menon , Stephen Boyd , Nikunj Kela , Prasad Sodagudi , Alexandre Torgue , linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 09/11] cpufreq: scmi: Add support to parse domain-id using #power-domain-cells Message-ID: <20230721115917.lescikl75kmeqkw4@bogus> References: <20230713141738.23970-1-ulf.hansson@linaro.org> <20230713141738.23970-10-ulf.hansson@linaro.org> <20230719152426.qwc5qqewrfjsarlz@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Fri, Jul 21, 2023 at 01:52:17PM +0200, Ulf Hansson wrote: > On Wed, 19 Jul 2023 at 17:24, Sudeep Holla wrote: > > > > On Thu, Jul 13, 2023 at 04:17:36PM +0200, Ulf Hansson wrote: > > > The performance domain-id can be described in DT using the power-domains > > > property or the clock property. The latter is already supported, so let's > > > add support for the power-domains too. > > > > > > > How is this supposed to work for the CPUs ? The CPU power domains are > > generally PSCI on most of the platforms and the one using OSI explicitly > > need to specify the details while ones using PC will not need to. Also they > > can never be performance domains too. So I am not sure if I am following this > > correctly. > > Your concerns are certainly correct, I completely forgot about this. > We need to specify what power-domain index belongs to what, by using > power-domain-names in DT. So a CPU node, that has both psci for power > and scmi for performance would then typically look like this: > > power-domains = <&CPU_PD0>, <&scmi_dvfs 4>; > power-domain-names = "psci", "scmi"; > > I will take care of this in the next version - and thanks a lot for > pointing this out! Yes something like this will work. Just curious will this impact the idle paths ? By that I mean will the presence of additional domains add more work or will they be skipped as early as possible with just one additional check ? -- Regards, Sudeep