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 X-Spam-Level: X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A956EC4363A for ; Fri, 23 Oct 2020 15:02:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5618B22210 for ; Fri, 23 Oct 2020 15:02:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S465404AbgJWPCP (ORCPT ); Fri, 23 Oct 2020 11:02:15 -0400 Received: from foss.arm.com ([217.140.110.172]:54672 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S461452AbgJWPCO (ORCPT ); Fri, 23 Oct 2020 11:02:14 -0400 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 4F0A2101E; Fri, 23 Oct 2020 08:02:14 -0700 (PDT) Received: from bogus (unknown [10.57.15.80]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EDE973F66E; Fri, 23 Oct 2020 08:02:12 -0700 (PDT) Date: Fri, 23 Oct 2020 15:58:02 +0100 From: Sudeep Holla To: Rob Herring Cc: "linux-kernel@vger.kernel.org" , devicetree@vger.kernel.org, linux-arm-kernel , Viresh Kumar Subject: Re: [PATCH 1/2] dt-bindings: arm,scmi: Do not use clocks for SCMI performance domains Message-ID: <20201023145802.wzb74hbuuiphgwvi@bogus> References: <20201020203710.10100-1-sudeep.holla@arm.com> <20201021163021.lkqhum3xnyzt6pir@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20171215 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Fri, Oct 23, 2020 at 08:21:21AM -0500, Rob Herring wrote: > On Wed, Oct 21, 2020 at 11:30 AM Sudeep Holla wrote: > > > > On Wed, Oct 21, 2020 at 11:20:27AM -0500, Rob Herring wrote: > > > On Tue, Oct 20, 2020 at 3:37 PM Sudeep Holla wrote: > > > > > > > > Commit dd461cd9183f ("opp: Allow dev_pm_opp_get_opp_table() to return > > > > -EPROBE_DEFER") handles -EPROBE_DEFER for the clock/interconnects within > > > > _allocate_opp_table() which is called from dev_pm_opp_add and it > > > > now propagates the error back to the caller. > > > > > > > > SCMI performance domain re-used clock bindings to keep it simple. However > > > > with the above mentioned change, if clock property is present in a device > > > > node, opps can't be added until clk_get succeeds. So in order to fix the > > > > issue, we can register dummy clocks which is completely ugly. > > > > > > > > Since there are no upstream users for the SCMI performance domain clock > > > > bindings, let us introduce separate performance domain bindings for the > > > > same. > > > > > > > > Signed-off-by: Sudeep Holla > > > > --- > > > > .../devicetree/bindings/arm/arm,scmi.txt | 19 ++++++++++++++++--- > > > > 1 file changed, 16 insertions(+), 3 deletions(-) > > > > > > > > Hi Rob/Viresh, > > > > > > > > This is actually a fix for the regression I reported here[1]. > > > > I am not adding fixes tag as I am targeting in the same release and > > > > also because it is not directly related. > > > > > > > > Regards, > > > > Sudeep > > > > > > > > [1] https://lore.kernel.org/r/20201015180555.gacdzkofpibkdn2e@bogus > > > > > > > > P.S.:/me records that this binding needs to be moved to yaml in v5.11 > > > > > > > > diff --git a/Documentation/devicetree/bindings/arm/arm,scmi.txt b/Documentation/devicetree/bindings/arm/arm,scmi.txt > > > > index 55deb68230eb..0a6c1b495403 100644 > > > > --- a/Documentation/devicetree/bindings/arm/arm,scmi.txt > > > > +++ b/Documentation/devicetree/bindings/arm/arm,scmi.txt > > > > @@ -44,7 +44,7 @@ as described in the following sections. If the platform supports dedicated > > > > mboxes, mbox-names and shmem shall be present in the sub-node corresponding > > > > to that protocol. > > > > > > > > -Clock/Performance bindings for the clocks/OPPs based on SCMI Message Protocol > > > > +Clock bindings for the clocks based on SCMI Message Protocol > > > > ------------------------------------------------------------ > > > > > > > > This binding uses the common clock binding[1]. > > > > @@ -52,6 +52,19 @@ This binding uses the common clock binding[1]. > > > > Required properties: > > > > - #clock-cells : Should be 1. Contains the Clock ID value used by SCMI commands. > > > > > > > > +Performance bindings for the OPPs based on SCMI Message Protocol > > > > +------------------------------------------------------------ > > > > + > > > > +Required properties: > > > > +- #perf-domain-cells: Should be 1. Contains the performance domain ID value > > > > + used by SCMI commands. > > > > > > When is this not 1 (IOW, you only need this if variable)? How would it > > > be used outside SCMI (given it has a generic name)? > > > > > > > Ah, I thought we need this if phandle is followed by 1 or more arguments. > > If it is not compulsory I can drop this or make it scmi specific if we > > need it. > > No, your options are fixed or variable number of cells. If this is > generic, then maybe it needs to be variable. If it's SCMI specific > then it can likely be fixed unless you can think of other information > you may need in the cells. > > > > > + > > > > +* Property arm,scmi-perf-domain > > > > > > Yet this doesn't have a generic name. You mentioned on IRC this is > > > aligned with QCom, but why can't QCom use the same property here? > > > > > > > This is SCMI firmware driven while they have hardware driven perf/freq > > domains. So different drivers, need to distinguish between the two. > > So what if they are different drivers. That's *always* the case. The > clock provider(s) for 'clocks' is different for every SoC? I doesn't > matter who is the provider, it's the same information being described. > More agreed, another one fresh on the list today[1] -- Regards, Sudeep [1] https://lore.kernel.org/lkml/1603441493-18554-3-git-send-email-hector.yuan@mediatek.com