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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 3EA55CA9EAE for ; Tue, 29 Oct 2019 20:16:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 05C3F2086A for ; Tue, 29 Oct 2019 20:16:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572380186; bh=mzrl9420Ovx3lQJ1vhZxCQsXwonFelXckxIqNI5fnYU=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=cSa59ID7VUgvz4fIejC4RSJuZyf4BHJL146mj25nzpnkZ1vNl3Xf65qJB66WB+YiE ZDkjcH66mdw2Sz2Nf4r83C424I+eb4fGZEhrRaTg1Oug+xhgKZHIi/QBKFuzUje4uc 9Jb6HPSOqvtVVzd3SAWc443786hymOJd9AwgiPUY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725959AbfJ2UQZ (ORCPT ); Tue, 29 Oct 2019 16:16:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:59368 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725840AbfJ2UQZ (ORCPT ); Tue, 29 Oct 2019 16:16:25 -0400 Received: from mail-qt1-f169.google.com (mail-qt1-f169.google.com [209.85.160.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AF96C21721; Tue, 29 Oct 2019 20:16:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572380183; bh=mzrl9420Ovx3lQJ1vhZxCQsXwonFelXckxIqNI5fnYU=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=Bzs0JsLJXxLNGTSfA3dRdgUWooXO3sHsJpKlHKkRlMTj+DU4za3swy8FwTd63nH1z jsd9x+mUuzHXUv1o3wCebCtqHdnF3TdZ/fDF0CM+U5Rs1eaAApmFcCRl7K5eZgUl+y rQpDDkwkkAcchWbuljHc9iSYc4QMzr13Adf6Vj7s= Received: by mail-qt1-f169.google.com with SMTP id x21so4981511qto.12; Tue, 29 Oct 2019 13:16:23 -0700 (PDT) X-Gm-Message-State: APjAAAXciRC8z1znzvw+ESjsoiFgvNJl81T3c2+OS07yuqiJh2vasOvg QpcknAZj4aVAyAb6tun/T8Jhd98lN+PiJGpRWA== X-Google-Smtp-Source: APXvYqw2bPo/mXUkmXIpei4kFmXMxOacUC63F3raNseUkPz2342X9y6B6fHT0p2dhZ4pVJPYLGheLckku0HHO05Qz90= X-Received: by 2002:ac8:741a:: with SMTP id p26mr1062486qtq.143.1572380182705; Tue, 29 Oct 2019 13:16:22 -0700 (PDT) MIME-Version: 1.0 References: <1571254641-13626-1-git-send-email-thara.gopinath@linaro.org> <1571254641-13626-7-git-send-email-thara.gopinath@linaro.org> <5DA88892.5000408@linaro.org> <5DA89267.30806@linaro.org> <20191029013648.GB27045@bogus> In-Reply-To: From: Rob Herring Date: Tue, 29 Oct 2019 15:16:11 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v3 6/7] dt-bindings: soc: qcom: Extend RPMh power controller binding to describe thermal warming device To: Ulf Hansson Cc: Thara Gopinath , Eduardo Valentin , Zhang Rui , Daniel Lezcano , Bjorn Andersson , Andy Gross , Amit Kucheria , Mark Rutland , "Rafael J. Wysocki" , Linux PM , DTML , linux-arm-msm , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Tue, Oct 29, 2019 at 5:07 AM Ulf Hansson wrote: > > On Tue, 29 Oct 2019 at 02:36, Rob Herring wrote: > > > > On Thu, Oct 17, 2019 at 12:10:15PM -0400, Thara Gopinath wrote: > > > On 10/17/2019 11:43 AM, Ulf Hansson wrote: > > > > On Thu, 17 Oct 2019 at 17:28, Thara Gopinath wrote: > > > >> > > > >> Hello Ulf, > > > >> Thanks for the review! > > > >> > > > >> On 10/17/2019 05:04 AM, Ulf Hansson wrote: > > > >>> On Wed, 16 Oct 2019 at 21:37, Thara Gopinath wrote: > > > >>>> > > > >>>> RPMh power controller hosts mx domain that can be used as thermal > > > >>>> warming device. Add a sub-node to specify this. > > > >>>> > > > >>>> Signed-off-by: Thara Gopinath > > > >>>> --- > > > >>>> Documentation/devicetree/bindings/power/qcom,rpmpd.txt | 10 ++++++++++ > > > >>>> 1 file changed, 10 insertions(+) > > > >>>> > > > >>>> diff --git a/Documentation/devicetree/bindings/power/qcom,rpmpd.txt b/Documentation/devicetree/bindings/power/qcom,rpmpd.txt > > > >>>> index eb35b22..fff695d 100644 > > > >>>> --- a/Documentation/devicetree/bindings/power/qcom,rpmpd.txt > > > >>>> +++ b/Documentation/devicetree/bindings/power/qcom,rpmpd.txt > > > >>>> @@ -18,6 +18,16 @@ Required Properties: > > > >>>> Refer to for the level values for > > > >>>> various OPPs for different platforms as well as Power domain indexes > > > >>>> > > > >>>> += SUBNODES > > > >>>> +RPMh alsp hosts power domains that can behave as thermal warming device. > > > >>>> +These are expressed as subnodes of the RPMh. The name of the node is used > > > >>>> +to identify the power domain and must therefor be "mx". > > > >>>> + > > > >>>> +- #cooling-cells: > > > >>>> + Usage: optional > > > >>>> + Value type: > > > >>>> + Definition: must be 2 > > > >>>> + > > > >>> > > > >>> Just wanted to express a minor thought about this. In general we use > > > >>> subnodes of PM domain providers to represent the topology of PM > > > >>> domains (subdomains), this is something different, which I guess is > > > >>> fine. > > > >>> > > > >>> I assume the #cooling-cells is here tells us this is not a PM domain > > > >>> provider, but a "cooling device provider"? > > > >> Yep. > > > >>> > > > >>> Also, I wonder if it would be fine to specify "power-domains" here, > > > >>> rather than using "name" as I think that is kind of awkward!? > > > >> Do you mean "power-domain-names" ? I am using this to match against the > > > >> genpd names defined in the provider driver. > > > > > > > > No. If you are using "power-domains" it means that you allow to > > > > describe the specifier for the provider. > > > Yep. But won't this look funny in DT ? The provider node will have a sub > > > node with a power domain referencing to itself Like below: Is this ok ? > > > > > > rpmhpd: power-controller { > > > compatible = "qcom,sdm845-rpmhpd"; > > > #power-domain-cells = <1>; > > > > > > ... > > > ... > > > mx_cdev: mx { > > > #cooling-cells = <2>; > > > power-domains = <&rpmhpd SDM845_MX>; > > > }; > > > > > > > The whole concept here seems all wrong to me. Isn't it what's in the > > power domain that's the cooling device. A CPU power domain is not a > > cooling device, the CPU is. Or we wouldn't make a clock a cooling > > device, but what the clock drives. > > Well, I don't think that's entirely correct description either. > > As I see it, it's really the actual PM domain (that manages voltages > for a power island), that needs to stay in full power state and > increase its voltage level, as to warm up some of the silicon. It's > not a regular device, but more a characteristics of how the PM domain > can be used. First I've heard of Si needing warming... I think I'd just expect the power domain provider to know which domains to power on then. Rob