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 CE999C433FE for ; Fri, 1 Apr 2022 13:39:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346419AbiDANlR (ORCPT ); Fri, 1 Apr 2022 09:41:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48250 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233738AbiDANlQ (ORCPT ); Fri, 1 Apr 2022 09:41:16 -0400 Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36FF3369D0; Fri, 1 Apr 2022 06:39:26 -0700 (PDT) X-UUID: 8ab153cf2a174978a12d51ea01efde35-20220401 X-UUID: 8ab153cf2a174978a12d51ea01efde35-20220401 Received: from mtkmbs10n1.mediatek.inc [(172.21.101.34)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1530467067; Fri, 01 Apr 2022 21:39:20 +0800 Received: from mtkexhb02.mediatek.inc (172.21.101.103) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 1 Apr 2022 21:39:16 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkexhb02.mediatek.inc (172.21.101.103) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 1 Apr 2022 21:39:16 +0800 Received: from mtksdccf07 (172.21.84.99) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Fri, 1 Apr 2022 21:39:15 +0800 Message-ID: <126e0905c2eb9f22a0be46dd7aa8ac891622346d.camel@mediatek.com> Subject: Re: [PATCH 1/3] dt-bindings: devfreq: mediatek: add mtk cci devfreq dt-bindings From: Jia-Wei Chang To: Krzysztof Kozlowski , MyungJoo Ham , Kyungmin Park , Chanwoo Choi , Rob Herring , Matthias Brugger , Liam Girdwood , Mark Brown CC: , , , , , , , , , , , Jia-Wei Chang Date: Fri, 1 Apr 2022 21:39:15 +0800 In-Reply-To: References: <20220307122513.11822-1-jia-wei.chang@mediatek.com> <20220307122513.11822-2-jia-wei.chang@mediatek.com> <13482b1b4244df5c0c0a4d6a60cdb2a7ba88500a.camel@mediatek.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2022-03-24 at 13:44 +0100, Krzysztof Kozlowski wrote: > On 24/03/2022 13:11, Jia-Wei Chang wrote: > > > > > > Remove "driver Device Tree Bindings". "Devfreq" is Linuxism, so > > > this > > > maybe "bus frequency scaling"? Although later you call the device > > > node > > > as cci. > > > > Should I use "Binding for MediaTek's Cache Coherent Interconnect > > (CCI) > > frequency and voltage scaling" as new title? > > I just suggested to remove word "bindings" so do not add it again. > This > should be a title for hardware. Sure, I will remove the word "bindings" from title. > > Now what exactly is it - you should know better than me. :) > "MediaTek's Cache Coherent Interconnect (CCI) frequency and voltage > scaling" sounds good to me, assuming that this is the hardware we > talk > here about. :) Appreciate your comments. It's a bit hard to do upstream at first time, thank you for understanding. > > > > > > > > > > + > > > > +maintainers: > > > > + - Jia-Wei Chang > > > > + > > > > +description: | > > > > + This module is used to create CCI DEVFREQ. > > > > + The performance will depend on both CCI frequency and CPU > > > > frequency. > > > > + For MT8186, CCI co-buck with Little core. > > > > + Contain CCI opp table for voltage and frequency scaling. > > > > > > Half of this description (first and last sentence) does not > > > describe > > > the > > > actual hardware. Please describe hardware, not driver. > > > > Sure, I will fix it in the next version. > > > > > > > > > + > > > > +properties: > > > > + compatible: > > > > + const: "mediatek,mt8186-cci" > > > > > > No need for quotes. > > > > Sure, I will fix it in the next version. > > > > > > > > > + > > > > + clocks: > > > > + items: > > > > + - description: > > > > + The first one is the multiplexer for clock input of > > > > CPU > > > > cluster. > > > > + - description: > > > > + The other is used as an intermediate clock source > > > > when > > > > the original > > > > + CPU is under transition and not stable yet. > > > > + > > > > + clock-names: > > > > + items: > > > > + - const: "cci" > > > > + - const: "intermediate" > > > > > > No need for quotes. > > > > Sure, I will fix it in the next version. > > > > > > > > > + > > > > + operating-points-v2: > > > > + description: > > > > + For details, please refer to > > > > + Documentation/devicetree/bindings/opp/opp-v2.yaml > > > > + > > > > + opp-table: true > > > > > > Same comments as your CPU freq bindings apply. > > > > mtk-cci-devfreq is a new driver and its arch is same as mediatek- > > cpufreq so that the properties of mtk-cci are refer to mediatek- > > cpufreq > > bindings. > > operating-point-v2 is used to determine the voltage and frequency > > of > > dvfs which is further utilized by mtk-cci-devfreq. > > "operating-point-v2" is understood, but the same as in cpufreq > bindings, > I am questioning why do you have "opp-table: true". It's a bit > confusing, so maybe I miss something? Yes, you're correct. "opp-table: true" should be removed. I messed it up. > > > > > > > > > > + > > > > + proc-supply: > > > > + description: > > > > + Phandle of the regulator for CCI that provides the > > > > supply > > > > voltage. > > > > + > > > > + sram-supply: > > > > + description: > > > > + Phandle of the regulator for sram of CCI that provides > > > > the > > > > supply > > > > + voltage. When present, the cci devfreq driver needs to > > > > do > > > > + "voltage tracking" to step by step scale up/down Vproc > > > > and > > > > Vsram to fit > > > > + SoC specific needs. When absent, the voltage scaling > > > > flow is > > > > handled by > > > > + hardware, hence no software "voltage tracking" is > > > > needed. > > > > + > > > > +required: > > > > + - compatible > > > > + - clocks > > > > + - clock-names > > > > + - operating-points-v2 > > > > + - proc-supply > > > > + > > > > +additionalProperties: false > > > > + > > > > +examples: > > > > + - | > > > > + #include > > > > + cci: cci { > > > > > > Node names should be generic and describe type of device. Are you > > > sure > > > this is a CCI? Maybe "interconnect" suits it better? > > > > Yes, this is a CCI and it is generic type of device like CPU in my > > opinion. > > If my understanding is correct, CCI is more suitable. > > OK. :) > > > > > > > > > > + compatible = "mediatek,mt8186-cci"; > > > > + clocks = <&mcusys CLK_MCU_ARMPLL_BUS_SEL>, <&apmixedsys > > > > CLK_APMIXED_MAINPLL>; > > > > + clock-names = "cci", "intermediate"; > > > > + operating-points-v2 = <&cci_opp>; > > > > + proc-supply = <&mt6358_vproc12_reg>; > > > > + sram-supply = <&mt6358_vsram_proc12_reg>; > > > > + }; > > > > > > > > > Best regards, > > > Krzysztof > > > Best regards, > Krzysztof