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=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID 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 58304C3279B for ; Tue, 10 Jul 2018 23:01:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E24A72098B for ; Tue, 10 Jul 2018 23:01:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="HaT1fAHp"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="HaT1fAHp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E24A72098B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732388AbeGJXC4 (ORCPT ); Tue, 10 Jul 2018 19:02:56 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:45144 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732276AbeGJXC4 (ORCPT ); Tue, 10 Jul 2018 19:02:56 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id E776C60B24; Tue, 10 Jul 2018 23:01:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1531263697; bh=03P4ahAw4J17GVKiRMukkfFr13hJ3TSITwAWtW6ldaM=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=HaT1fAHpMAy+MTBtZR+s61a9tva71ozT4qZZ4W+rfuiwPQEMEjWnyHA1FcxjuyAwi 5zHAPBLrnDdnlJnCH4husMDrER1a7fCZ7oijr/GB1pKtQeC2M7GLngnkTBR/XTTMiL NJy3NTmcijdlDjLFPWRH3cR2otkzDRFX93wDFsrs= Received: from [10.46.160.165] (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: collinsd@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 6AAF860452; Tue, 10 Jul 2018 23:01:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1531263697; bh=03P4ahAw4J17GVKiRMukkfFr13hJ3TSITwAWtW6ldaM=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=HaT1fAHpMAy+MTBtZR+s61a9tva71ozT4qZZ4W+rfuiwPQEMEjWnyHA1FcxjuyAwi 5zHAPBLrnDdnlJnCH4husMDrER1a7fCZ7oijr/GB1pKtQeC2M7GLngnkTBR/XTTMiL NJy3NTmcijdlDjLFPWRH3cR2otkzDRFX93wDFsrs= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 6AAF860452 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=collinsd@codeaurora.org Subject: Re: [PATCH 2/3] arm64: dts: qcom: sdm845-mtp: Add RPMh VRM/XOB regulators To: Doug Anderson Cc: Andy Gross , Bjorn Andersson , Stephen Boyd , Tomasz Figa , Manu Gautam , Vivek Gautam , devicetree@vger.kernel.org, linux-arm-msm , LKML , Rob Herring , David Brown , Will Deacon , Mark Rutland , "open list:ARM/QUALCOMM SUPPORT" , Catalin Marinas , Linux ARM References: <20180710220202.116404-1-dianders@chromium.org> <20180710220202.116404-3-dianders@chromium.org> <0d334051-2ba5-075d-df8c-affe3e617e8d@codeaurora.org> From: David Collins Message-ID: <05f5afbf-61cd-77e8-3a02-1166d1c1ad4f@codeaurora.org> Date: Tue, 10 Jul 2018 16:01:35 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 07/10/2018 03:55 PM, Doug Anderson wrote: > On Tue, Jul 10, 2018 at 3:32 PM, David Collins wrote: >> On 07/10/2018 03:02 PM, Douglas Anderson wrote: >> ... >>> + vdd-s1-supply = <&vph_pwr>; >>> + vdd-s2-supply = <&vph_pwr>; >>> + vdd-s3-supply = <&vph_pwr>; >>> + vdd-s4-supply = <&vph_pwr>; >>> + vdd-s5-supply = <&vph_pwr>; >>> + vdd-s6-supply = <&vph_pwr>; >>> + vdd-s7-supply = <&vph_pwr>; >>> + vdd-s8-supply = <&vph_pwr>; >>> + vdd-s9-supply = <&vph_pwr>; >>> + vdd-s10-supply = <&vph_pwr>; >>> + vdd-s11-supply = <&vph_pwr>; >>> + vdd-s12-supply = <&vph_pwr>; >>> + vdd-s13-supply = <&vph_pwr>; >>> + vdd-l1-l27-supply = <&vreg_s7a_1p025>; >>> + vdd-l2-l8-l17-supply = <&vreg_s3a_1p35>; >>> + vdd-l3-l11-supply = <&vreg_s7a_1p025>; >>> + vdd-l4-l5-supply = <&vreg_s7a_1p025>; >>> + vdd-l6-supply = <&vph_pwr>; >>> + vdd-l7-l12-l14-l15-supply = <&vreg_s5a_2p04>; >>> + vdd-l9-supply = <&vreg_bob>; >>> + vdd-l10-l23-l25-supply = <&vreg_bob>; >>> + vdd-l13-l19-l21-supply = <&vreg_bob>; >>> + vdd-l16-l28-supply = <&vreg_bob>; >>> + vdd-l18-l22-supply = <&vreg_bob>; >>> + vdd-l20-l24-supply = <&vreg_bob>; >>> + vdd-l26-supply = <&vreg_s3a_1p35>; >>> + vin-lvs-1-2-supply = <&vreg_s4a_1p8>; >> >> I would suggest not specifying any of these regulator parent supplies in >> device tree. RPMh will be enforcing all regulator parent-child >> dependencies. Therefore, handling the dependencies in Linux is redundant. >> It will result in additional RPMh requests as well as more time spent in >> regulator framework calls. Overall, it will lead to slightly lower >> performance. Note that while specifying the parent supplies results in >> less efficient runtime behavior, it is not technically wrong so you could >> keep them in place if you prefer. > > Interesting. ...so RPMh will automatically turn on parent regulators > when their children are enabled (assuming that the parent regulator is > also RPMh controlled)? Yes, exactly. RPMh also ensures that the voltage of a parent regulator is sufficient to meet minimum headroom voltage requirements of all subregulated child regulators. > Personally I'd still prefer to see Linux managing its own state and > relying less on RPMh-automatic stuff, but I'd defer to Bjorn / Andy > (or others) to override me. Ok Take care, David -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project