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 BC202EB64DB for ; Thu, 15 Jun 2023 07:52:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245233AbjFOHwn (ORCPT ); Thu, 15 Jun 2023 03:52:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37094 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244924AbjFOHwe (ORCPT ); Thu, 15 Jun 2023 03:52:34 -0400 Received: from mail-lf1-x130.google.com (mail-lf1-x130.google.com [IPv6:2a00:1450:4864:20::130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C79112724 for ; Thu, 15 Jun 2023 00:52:13 -0700 (PDT) Received: by mail-lf1-x130.google.com with SMTP id 2adb3069b0e04-4f766777605so2431534e87.1 for ; Thu, 15 Jun 2023 00:52:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1686815529; x=1689407529; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=OnLAb/o5l2EuhHYqpE8y7BrnGhDNpYQ/A+Vx7BWAr88=; b=wp56Ds3X9nkSr0F9ISHqBFM4O4uRWA1NeoaGxPwb6kiQi+kk/eQZdCCTtv3Nsm1OSB 6sUSNcaqWAmbQO6qBPjhrlbTIhIVOnOdsdscPQD7utiRhUsQktfmZmsJ4a52zMWauGX2 zgghpDCVOZDmQOs2TVaW3irBNAbVz+tErqkdOvYu0/pHwviwCdcJsHbTf21gd1/JyPPR fkxUPmXDEVjk4bjx+tlRH3+sgrOY7L5x+Xu23R44MwyWa+Dt/yEYCwOH6Ie3uP2GfZeY y/vxaIj/CtXOIEoGzjaUJ/UiJexwcqhdzmB+XwPMQjeFbKMSyyuBCXFDV/9bJnq4CJuh XbjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686815529; x=1689407529; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=OnLAb/o5l2EuhHYqpE8y7BrnGhDNpYQ/A+Vx7BWAr88=; b=bVRGg2l0IMHxUFvgIak/HgPykP19xdGqaFcHmEG4xlKfj6ALCAo6u9AMST+FJa8Ylh RTpI1yFgBllp6gWDO77c4jO/h9lStxfuqojimbWAvxxBNuaCMorMdxEtlvNUe+XCXTgM ZOpl8MUGrSLhUFjitT+Lebrl/+8PQk/iD0aYBAl9cLsdKYQr3GCPbryHuAsVlazVC/Zi lYYSQfunrMoPmWapS2N0grcsbJDMGk0HpEj4DJDBJAwAZ30A9o4nF4RzBWn1aQ/wkuyA uPpwH750gWGjSLNUBYFZbOCV29OGnVARR99mwU0CLihRkGA5T9AXArygo6vJicV5rTYQ I3Kg== X-Gm-Message-State: AC+VfDzkiu6y9K1UwSwtaL+dIoW5PQiRajT2zeEpddp/GGlizQdLqMTG hlkd23uCGztW2bJL+cLz/BU5ng== X-Google-Smtp-Source: ACHHUZ6byeATepKDfRbb48D1WYuexmYDvekDU3GjrZKiJbCCViAjaUqDxWYYkI3TFgnr+axOqZQCiw== X-Received: by 2002:a05:6512:1cd:b0:4f4:dd51:aec7 with SMTP id f13-20020a05651201cd00b004f4dd51aec7mr8412115lfp.54.1686815529466; Thu, 15 Jun 2023 00:52:09 -0700 (PDT) Received: from [192.168.1.101] (abyj190.neoplus.adsl.tpnet.pl. [83.9.29.190]) by smtp.gmail.com with ESMTPSA id w15-20020ac2598f000000b004f138ecab11sm2482805lfn.24.2023.06.15.00.52.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 15 Jun 2023 00:52:09 -0700 (PDT) Message-ID: <8568eead-90f6-ce15-d483-4d72dbab6294@linaro.org> Date: Thu, 15 Jun 2023 09:52:07 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.2 Subject: Re: [PATCH v6 00/22] Restructure RPM SMD ICC Content-Language: en-US To: Stephen Boyd , Andy Gross , Bjorn Andersson , Conor Dooley , Evan Green , Georgi Djakov , Krzysztof Kozlowski , Leo Yan , Michael Turquette , Rob Herring Cc: Marijn Suijten , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-pm@vger.kernel.org, devicetree@vger.kernel.org, Krzysztof Kozlowski , Dmitry Baryshkov , Stephan Gerhold References: <20230526-topic-smd_icc-v6-0-263283111e66@linaro.org> <0764b5fda92acb995ffbd05c4b3d2b2f.sboyd@kernel.org> From: Konrad Dybcio In-Reply-To: <0764b5fda92acb995ffbd05c4b3d2b2f.sboyd@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 15.06.2023 02:49, Stephen Boyd wrote: > Quoting Konrad Dybcio (2023-06-14 11:04:19) >> This series reshuffles things around, moving the management of SMD RPM >> bus clocks to the interconnect framework where they belong. This helps >> us solve a couple of issues: >> >> 1. We can work towards unused clk cleanup of RPMCC without worrying >> about it killing some NoC bus, resulting in the SoC dying. >> Deasserting actually unused RPM clocks (among other things) will >> let us achieve "true SoC-wide power collapse states", also known as >> VDD_LOW and VDD_MIN. >> >> 2. We no longer have to keep tons of quirky bus clock ifs in the icc >> driver. You either have a RPM clock and call "rpm set rate" or you >> have a single non-RPM clock (like AHB_CLK_SRC) or you don't have any. >> >> 3. There's less overhead - instead of going through layers and layers of >> the CCF, ratesetting comes down to calling max() and sending a single >> RPM message. ICC is very very dynamic so that's a big plus. >> >> The clocks still need to be vaguely described in the clk-smd-rpm driver, >> as it gives them an initial kickoff, before actually telling RPM to >> enable DVFS scaling. After RPM receives that command, all clocks that >> have not been assigned a rate are considered unused and are shut down >> in hardware, leading to the same issue as described in point 1. > > Why can't we move the enable of DVFS scaling call to the interconnect > driver as well? We want the clk driver to not reference the interconnect > resources at all. That would result in no rpmcc ratesetting on platforms without a functional interconnect driver. The DVFS call concerns both bus and !bus clocks. Konrad