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=-15.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 D96DDC4338F for ; Wed, 4 Aug 2021 11:08:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B20FC60200 for ; Wed, 4 Aug 2021 11:08:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237342AbhHDLIu (ORCPT ); Wed, 4 Aug 2021 07:08:50 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:34053 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236976AbhHDLIs (ORCPT ); Wed, 4 Aug 2021 07:08:48 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1628075316; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: References: Cc: To: From: Subject: Sender; bh=UVTxmTbmqtIP0faK96taKsK1cEYi8KSQOq1LNUgnXtI=; b=W5SmWbbtzE6BLevG3qAqD2o9OGYejomMJV1EQe7jp/bUU+sB3+TEqNrLkdG5Js9aHd1+xBdM mIgwpbGPjSjIrXeiTWpmrFWd2vHY9NvOM3KAQkmDwG/xmAyZeFkntfNHnBz25ElA8+dBpMCy ERmJamXq+BDfPxXPX3qalPTumqA= X-Mailgun-Sending-Ip: 198.61.254.9 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== 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-east-1.postgun.com with SMTP id 610a75205c73bba6fb3a57de (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 04 Aug 2021 11:08:16 GMT Sender: rnayak=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id E6450C43217; Wed, 4 Aug 2021 11:08:15 +0000 (UTC) Received: from [192.168.1.102] (unknown [49.207.203.214]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: rnayak) by smtp.codeaurora.org (Postfix) with ESMTPSA id F06DDC433D3; Wed, 4 Aug 2021 11:08:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org F06DDC433D3 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=rnayak@codeaurora.org Subject: Re: [PATCH v5 1/2] PM / Domains: Add support for 'required-opps' to set default perf state From: Rajendra Nayak To: Ulf Hansson Cc: Bjorn Andersson , Viresh Kumar , Linux PM , DTML , Linux Kernel Mailing List , linux-arm-msm , Stephen Boyd , Roja Rani Yarubandi , Stephan Gerhold References: <1626764876-10229-1-git-send-email-rnayak@codeaurora.org> <1626764876-10229-2-git-send-email-rnayak@codeaurora.org> <35950d34-5cab-1b09-9864-49217a83f68d@codeaurora.org> Message-ID: <6fe7d326-1822-5a49-cca7-df9a2739dca8@codeaurora.org> Date: Wed, 4 Aug 2021 16:38:09 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <35950d34-5cab-1b09-9864-49217a83f68d@codeaurora.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 8/3/2021 10:08 AM, Rajendra Nayak wrote: > > On 8/2/2021 6:29 PM, Ulf Hansson wrote: >> On Tue, 20 Jul 2021 at 09:12, Rajendra Nayak wrote: >>> >>> Some devices within power domains with performance states do not >>> support DVFS, but still need to vote on a default/static state >>> while they are active. They can express this using the 'required-opps' >>> property in device tree, which points to the phandle of the OPP >>> supported by the corresponding power-domains. >>> >>> Add support to parse this information from DT and then set the >>> specified performance state during attach and drop it on detach. >>> runtime suspend/resume callbacks already have logic to drop/set >>> the vote as needed and should take care of dropping the default >>> perf state vote on runtime suspend and restore it back on runtime >>> resume. >>> >>> Signed-off-by: Rajendra Nayak >>> --- >>>   drivers/base/power/domain.c | 28 +++++++++++++++++++++++++--- >>>   include/linux/pm_domain.h   |  1 + >>>   2 files changed, 26 insertions(+), 3 deletions(-) >>> >>> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c >>> index a934c67..f454031 100644 >>> --- a/drivers/base/power/domain.c >>> +++ b/drivers/base/power/domain.c >>> @@ -2598,6 +2598,12 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off) >>> >>>          dev_dbg(dev, "removing from PM domain %s\n", pd->name); >>> >>> +       /* Drop the default performance state */ >>> +       if (dev_gpd_data(dev)->default_pstate) { >>> +               dev_pm_genpd_set_performance_state(dev, 0); >>> +               dev_gpd_data(dev)->default_pstate = 0; >>> +       } >>> + >>>          for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) { >>>                  ret = genpd_remove_device(pd, dev); >>>                  if (ret != -EAGAIN) >>> @@ -2635,9 +2641,10 @@ static void genpd_dev_pm_sync(struct device *dev) >>>   static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev, >>>                                   unsigned int index, bool power_on) >>>   { >>> +       struct device_node *np; >>>          struct of_phandle_args pd_args; >>>          struct generic_pm_domain *pd; >>> -       int ret; >>> +       int ret, pstate; >>> >>>          ret = of_parse_phandle_with_args(dev->of_node, "power-domains", >>>                                  "#power-domain-cells", index, &pd_args); >>> @@ -2675,10 +2682,25 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev, >>>                  genpd_unlock(pd); >>>          } >>> >>> -       if (ret) >>> +       if (ret) { >>>                  genpd_remove_device(pd, dev); >>> +               return -EPROBE_DEFER; >>> +       } >>> + >>> +       /* Set the default performance state */ >>> +       np = base_dev->of_node; >> >> Please use dev->of_node instead (it is set to the same of_node as >> base_dev by the callers of __genpd_dev_pm_attach) as it's more >> consistent with existing code. >> >>> +       if (of_parse_phandle(np, "required-opps", index)) { >>> +               pstate = of_get_required_opp_performance_state(np, index); >>> +               if (pstate < 0) { >>> +                       ret = pstate; >>> +                       dev_err(dev, "failed to set required performance state for power-domain %s: %d\n", >>> +                               pd->name, ret); >>> +               } >>> +               dev_pm_genpd_set_performance_state(dev, pstate); >>> +               dev_gpd_data(dev)->default_pstate = pstate; >> >> This doesn't look entirely correct to me. If we fail to translate a >> required opp to a performance state, we shouldn't try to set it. > > yeah, that does not seem right at all :( > >> Perhaps it's also easier to call >> of_get_required_opp_performance_state() unconditionally of whether a >> "required-opps" specifier exists. If it fails with the translation, >> then we just skip setting a default state and continue with returning >> 1. >> >> Would that work? Looks like calling of_get_required_opp_performance_state() unconditionally makes it spit out a pr_err() in case the node is missing "required-opps" property, so I posted a v6 [1] with the check in place and adding the missing else condition. [1] https://lore.kernel.org/patchwork/project/lkml/list/?series=510727 -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation