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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 73138C433E7 for ; Mon, 31 Aug 2020 05:45:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 52CDB20578 for ; Mon, 31 Aug 2020 05:45:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="p1JxEcI9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726384AbgHaFpy (ORCPT ); Mon, 31 Aug 2020 01:45:54 -0400 Received: from mail29.static.mailgun.info ([104.130.122.29]:26190 "EHLO mail29.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726244AbgHaFpx (ORCPT ); Mon, 31 Aug 2020 01:45:53 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1598852751; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=Iy+aS17ropB49yr1viRv2PHOc4XtCCzAiTjV0hpucD0=; b=p1JxEcI9zwLiaKMteissaxp/AgYcNC/xAx3Xeuo2yBCsrUt3ZoGUjg7uDeyETAOUdKFHHlqk pjrfuT2+Ce6QyabfLzHBatCiZ1vzi61y4g9yLL6c78+ssX1z9k6B/B7cW2fG2s3KowsnhQwR oXrM6u+AmWtPYpjqEJs2YBf2HYw= X-Mailgun-Sending-Ip: 104.130.122.29 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-west-2.postgun.com with SMTP id 5f4c8e8f2583507e9292f1a0 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 31 Aug 2020 05:45:51 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id B1961C43395; Mon, 31 Aug 2020 05:45:50 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: sibis) by smtp.codeaurora.org (Postfix) with ESMTPSA id 24F6DC433CA; Mon, 31 Aug 2020 05:45:50 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 31 Aug 2020 11:15:50 +0530 From: Sibi Sankar To: Viresh Kumar Cc: Ansuel Smith , vincent.guittot@linaro.org, saravanak@google.com, Sudeep Holla , "Rafael J. Wysocki" , Rob Herring , linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v3 0/2] Add Krait Cache Scaling support In-Reply-To: <20200824104053.kpjpwzl2iw3lpg2m@vireshk-i7> References: <20200821140026.19643-1-ansuelsmth@gmail.com> <20200824104053.kpjpwzl2iw3lpg2m@vireshk-i7> Message-ID: X-Sender: sibis@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-08-24 16:10, Viresh Kumar wrote: > +Vincent/Saravana/Sibi > > On 21-08-20, 16:00, Ansuel Smith wrote: >> This adds Krait Cache scaling support using the cpufreq notifier. >> I have some doubt about where this should be actually placed (clk or >> cpufreq)? >> Also the original idea was to create a dedicated cpufreq driver (like >> it's done in >> the codeaurora qcom repo) by copying the cpufreq-dt driver and adding >> the cache >> scaling logic but i still don't know what is better. Have a very >> similar driver or >> add a dedicated driver only for the cache using the cpufreq notifier >> and do the >> scale on every freq transition. >> Thanks to everyone who will review or answer these questions. > > Saravana was doing something with devfreq to solve such issues if I > wasn't mistaken. > > Sibi ? IIRC the final plan was to create a devfreq device and devfreq-cpufreq based governor to scale them, this way one can switch to a different governor if required. (I don't see if ^^ applies well for l2 though). In the interim until such a solution is acked on the list we just scale the resources directly from the cpufreq driver. On SDM845/SC7180 SoCs, L3 is modeled as a interconnect provider and is directly scaled from the cpufreq-hw driver. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.