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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09D23C43217 for ; Mon, 27 Sep 2021 17:06:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E00706120A for ; Mon, 27 Sep 2021 17:06:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236153AbhI0RIM (ORCPT ); Mon, 27 Sep 2021 13:08:12 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:57260 "EHLO fanzine.igalia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236030AbhI0RHM (ORCPT ); Mon, 27 Sep 2021 13:07:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:Subject; bh=U/wvgLLi41m18RNuqWjpTNZ1j3Iee5ygCK7QikzhmQI=; b=ehjomNjeRHeDwAM3pAbEpBO3dSKHbYD1adnhVgPiTW7u4mDahydMDn/fmVIjijydzqpEP1lW+/VMVf2OAOUiWes0MwdOOK/VywvnHfhyosr51vOhLlSDZE+fxLoGsdzNTtQVv3TRBw47vymbkpNJztrRs/+rctu6ANgIQnqMQrAUsQ+Tc/EOgd2fbgBkpDf0FNNzj9n6TVGudV2Tu5jgWs/3LVzMU7l+XZBlQYMfAAqRsprdyfACotr1MQ+aKveezfvX014VyhwQPxeFgx+t4mPMyvbVcylYUS9tRcTNOmdZPLuSjBOr2Yt40yuOuHS53Nme8fCw1RNbV1p0cyrIpw==; Received: from [177.95.15.66] (helo=[192.168.1.64]) by fanzine.igalia.com with esmtpsa (Cipher TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim) id 1mUtfA-0005rt-07; Mon, 27 Sep 2021 18:39:32 +0200 Subject: Re: [PATCH] arm64: dts: qcom: db820c: Improve regulator voltage range and mark it as always-on Cc: linux-arm-msm@vger.kernel.org, agross@kernel.org, bjorn.andersson@linaro.org, kernel@gpiccoli.net, rnayak@codeaurora.org, vkoul@kernel.org References: <20210927163745.2066610-1-gpiccoli@igalia.com> From: "Guilherme G. Piccoli" Message-ID: <1de7abe9-c809-952e-aab2-afedff411a83@igalia.com> Date: Mon, 27 Sep 2021 13:39:19 -0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210927163745.2066610-1-gpiccoli@igalia.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 27/09/2021 13:37, Guilherme G. Piccoli wrote: > Commit 2317b87a2a6f ("arm64: dts: qcom: db820c: Add vdd_gfx and tie it into mmcc") > introduced this voltage regulator which seems to be essential for the GPU, > according to the board schematics [0]. The problem is that such commit sets > the regulator min/max voltage range to a static value, which is a bit lower than > the range supported to such regulator [1]. With that, the GPU is not stable > as per my experiments (in a Dragonboard 820c-based board) - I've observed > sudden reboots into a FW bad state. > > More than that, my experiment showed that this regulator must be set to > always-on - this idea came from a commit in Linaro's tree, from Rajendra [2]. > With the voltage range updated plus set as always-on, the GPU is working > correctly, in a stable fashion. > > [0] See page 9 (VDD_GFX), at > https://www.96boards.org/documentation/consumer/dragonboard/dragonboard820c/hardware-docs/files/db820c-schematics.pdf > > [1] See section 3.5.3 (FT-SMPS) in the "PMI8994/PMI8996 Power Management IC", > at https://developer.qualcomm.com/download/sd820e/pmi8994pmi8996-power-management-ic-device-specification.pdf > > [2] https://git.linaro.org/landing-teams/working/qualcomm/kernel.git/commit/?h=release/qcomlt-4.14&id=75fb43f3a62 > > Cc: Rajendra Nayak > Cc: Vinod Koul > Fixes: 2317b87a2a6f ("arm64: dts: qcom: db820c: Add vdd_gfx and tie it into mmcc") > Signed-off-by: Guilherme G. Piccoli > --- > > Hi Andy/Bjorn/all, this patch was tested in 5.14, but I've tested it > in the linux-next tree as well and was able to apply there cleanly. > I'm new in the DTS world, so my apologies in advance for any rookie > mistake - suggestions are appreciated! Thanks in advance for the review, > > > Guilherme > > > arch/arm64/boot/dts/qcom/apq8096-db820c.dtsi | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/boot/dts/qcom/apq8096-db820c.dtsi b/arch/arm64/boot/dts/qcom/apq8096-db820c.dtsi > index 51e17094d7b1..977842068619 100644 > --- a/arch/arm64/boot/dts/qcom/apq8096-db820c.dtsi > +++ b/arch/arm64/boot/dts/qcom/apq8096-db820c.dtsi > @@ -699,8 +699,11 @@ &pmi8994_spmi_regulators { > vdd_gfx: s2@1700 { > reg = <0x1700 0x100>; > regulator-name = "VDD_GFX"; > - regulator-min-microvolt = <980000>; > - regulator-max-microvolt = <980000>; > + regulator-min-microvolt = <350000>; > + regulator-max-microvolt = <1350000>; > + regulator-always-on; > + status = "okay"; > + > }; > }; > > Sorry, due to a git bad config, it supressed all CCs - adding them now!