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 38470C19F2D for ; Sat, 6 Aug 2022 20:20:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229639AbiHFUU5 (ORCPT ); Sat, 6 Aug 2022 16:20:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232126AbiHFUUz (ORCPT ); Sat, 6 Aug 2022 16:20:55 -0400 Received: from mail-lj1-x230.google.com (mail-lj1-x230.google.com [IPv6:2a00:1450:4864:20::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BF57F5B6 for ; Sat, 6 Aug 2022 13:20:53 -0700 (PDT) Received: by mail-lj1-x230.google.com with SMTP id w15so6291547ljw.1 for ; Sat, 06 Aug 2022 13:20:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc; bh=QVvsJ9CeX2LySg7T0a1qFniCTfiEl+1nmmOnQ6I/W54=; b=m0DytzPcDjf+Z/i78J8beCsf8lFs2h7nq5LA4XoB4RUuZ6OuqRiCPaHU1ADZ9nasVx UGLfqyKfPfGFA+imUTd8FtvIu/MH0sCh2b3ofv3W9Nu/H7JA9LpbIK+gksqQGV6KQZFh hAGvJJveTRt0y6G0hClbxtTvtD6EwyWdO3I+zGrQBuWdDXKMzEMIlrzcv8w0pUroXL8A jCqRnOkSFaHiVyLNyAVzyB1a3wanG3QxIcVLjeALGjruziQ6jnVEOn6Qd+WcjeMKQ0i/ VnQae5ZHloUn7l9pnWA9BW5bGo9iedpcapJOeyvtqNr4WypkPe+wjGeFsZjsBexun7Jj X0mg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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; bh=QVvsJ9CeX2LySg7T0a1qFniCTfiEl+1nmmOnQ6I/W54=; b=KxwwFQ6CJKAEE7mY6T8jPkToQERFB/AOZZqqBWOyxyK22c/uL5NCSo+SCv3DirLiFj MqnUkpXO62kc8s2K61C4qZjKqmlwBDyWbCZVj1sfYcIGDJSj2JPwO7ZvjtZzKhfZ9slW /vgVP5bnN7oWoV7NrysZy6p4ukvLFeLwSLa4GWzQPCny1IdOBAZ1ZicltoTS8u1ovi/r sEu/eMj/+eG9Ba2CqCXTr1PUC/8DiajQblKwyYkEF6ka+da4iyqroem+REkX9uPE5/Ro oVIOtSjR/MWfcwvmv18AEaPWNurZ0tFbwWrwg4JxflDOWflnsFYYlvFDcZPUrWbDK0dM Lz4w== X-Gm-Message-State: ACgBeo3nrCE1VvhTuoUK4+vnQX2d+Hpw6L8qBkNRZyUXUT4eXteV+fT8 AsLb2mYi0rZf+p3V3xvnShik9w== X-Google-Smtp-Source: AA6agR5Kqg8Mpuqsnv2emPbDL4T7Y79AFQz4eRCHargpsWvNUlbqO8mxGrJxanpWRr3pij4v4ogvgg== X-Received: by 2002:a2e:921a:0:b0:25e:b171:1f39 with SMTP id k26-20020a2e921a000000b0025eb1711f39mr2132144ljg.3.1659817251284; Sat, 06 Aug 2022 13:20:51 -0700 (PDT) Received: from [192.168.1.211] ([37.153.55.125]) by smtp.gmail.com with ESMTPSA id be9-20020a056512250900b0048b03ec561fsm866689lfb.150.2022.08.06.13.20.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 06 Aug 2022 13:20:50 -0700 (PDT) Message-ID: Date: Sat, 6 Aug 2022 23:20:50 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 Subject: Re: [PATCH] soc: qcom: rpmhpd: Use highest corner until sync_state Content-Language: en-GB To: Bjorn Andersson , Andy Gross , Konrad Dybcio Cc: linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Abel Vesa , Rajendra Nayak References: <20220806155035.968340-1-bjorn.andersson@linaro.org> From: Dmitry Baryshkov In-Reply-To: <20220806155035.968340-1-bjorn.andersson@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/08/2022 18:50, Bjorn Andersson wrote: > In some cases the hardware that the bootloader has left configured > depends on RPMH power domains for their operation up until the point > where the related Linux device driver probes and can inherit that > configuration, or power down the hardware gracefully. > > Unfortunately as Linux probes the releavant drivers in sequence there > are periods during the Linux boot flow where either the genpd refcount > will reach 0, or worse where the active performance_state votes does not > meet the requirements of the state that the hardware was left in. > > One specific example of this is during boot of e.g. SM8150/SC8180X, > where the display clock controller probes, without any particular > performance state needs (to access its registers). This will drop the > MMCX rail to MIN_SVS, which isn't sufficient to sustain the clock rates > that the later probing MDP is configured to. This results in an > unrecoverable system state. > > Handle both these cases by keeping the RPMH power-domais that are > referenced voted for highest state, until sync_state indicates that all > devices referencing the RPMH power-domain driver has been probed. > > Signed-off-by: Bjorn Andersson Reviewed-by: Dmitry Baryshkov > --- > drivers/soc/qcom/rpmhpd.c | 35 ++++++++++++++++++++++++++++++++++- > 1 file changed, 34 insertions(+), 1 deletion(-) > > diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c > index 092f6ab09acf..494bb6c75ed7 100644 > --- a/drivers/soc/qcom/rpmhpd.c > +++ b/drivers/soc/qcom/rpmhpd.c > @@ -39,6 +39,7 @@ > * @res_name: Resource name used for cmd-db lookup > * @addr: Resource address as looped up using resource name from > * cmd-db > + * @state_synced: Indicator that sync_state has been invoked for the rpmhpd resource > */ > struct rpmhpd { > struct device *dev; > @@ -54,6 +55,7 @@ struct rpmhpd { > bool enabled; > const char *res_name; > u32 addr; > + bool state_synced; > }; > > struct rpmhpd_desc { > @@ -493,7 +495,13 @@ static int rpmhpd_aggregate_corner(struct rpmhpd *pd, unsigned int corner) > unsigned int this_active_corner = 0, this_sleep_corner = 0; > unsigned int peer_active_corner = 0, peer_sleep_corner = 0; > > - to_active_sleep(pd, corner, &this_active_corner, &this_sleep_corner); > + if (pd->state_synced) { > + to_active_sleep(pd, corner, &this_active_corner, &this_sleep_corner); > + } else { > + /* Clamp to highest corner if sync_state hasn't happened */ > + this_active_corner = pd->level_count - 1; > + this_sleep_corner = pd->level_count - 1; > + } > > if (peer && peer->enabled) > to_active_sleep(peer, peer->corner, &peer_active_corner, > @@ -708,11 +716,36 @@ static int rpmhpd_probe(struct platform_device *pdev) > return of_genpd_add_provider_onecell(pdev->dev.of_node, data); > } > > +static void rpmhpd_sync_state(struct device *dev) > +{ > + const struct rpmhpd_desc *desc = of_device_get_match_data(dev); > + struct rpmhpd **rpmhpds = desc->rpmhpds; > + unsigned int corner; > + struct rpmhpd *pd; > + unsigned int i; > + > + mutex_lock(&rpmhpd_lock); > + for (i = 0; i < desc->num_pds; i++) { > + pd = rpmhpds[i]; > + if (!pd) > + continue; > + > + pd->state_synced = true; > + if (pd->enabled) > + corner = max(pd->corner, pd->enable_corner); > + else > + corner = 0; > + rpmhpd_aggregate_corner(pd, corner); > + } > + mutex_unlock(&rpmhpd_lock); > +} > + > static struct platform_driver rpmhpd_driver = { > .driver = { > .name = "qcom-rpmhpd", > .of_match_table = rpmhpd_match_table, > .suppress_bind_attrs = true, > + .sync_state = rpmhpd_sync_state, > }, > .probe = rpmhpd_probe, > }; -- With best wishes Dmitry