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=-11.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 143C4C433E6 for ; Tue, 1 Sep 2020 13:35:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E56B6206EB for ; Tue, 1 Sep 2020 13:35:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728245AbgIANeu (ORCPT ); Tue, 1 Sep 2020 09:34:50 -0400 Received: from foss.arm.com ([217.140.110.172]:41646 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727937AbgIANcY (ORCPT ); Tue, 1 Sep 2020 09:32:24 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D0C4B1FB; Tue, 1 Sep 2020 06:32:23 -0700 (PDT) Received: from bogus (unknown [10.57.5.92]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 116403F66F; Tue, 1 Sep 2020 06:32:20 -0700 (PDT) Date: Tue, 1 Sep 2020 14:32:18 +0100 From: Sudeep Holla To: Ulf Hansson Cc: Lorenzo Pieralisi , linux-pm@vger.kernel.org, "Rafael J . Wysocki" , Daniel Lezcano , Mark Rutland , Lina Iyer , Lukasz Luba , Vincent Guittot , Stephen Boyd , Sudeep Holla , Bjorn Andersson , Benjamin Gaignard , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 2/2] cpuidle: psci: Allow PM domain to be initialized even if no OSI mode Message-ID: <20200901133218.GB27090@bogus> References: <20200901121226.217568-1-ulf.hansson@linaro.org> <20200901121226.217568-3-ulf.hansson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200901121226.217568-3-ulf.hansson@linaro.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Tue, Sep 01, 2020 at 02:12:26PM +0200, Ulf Hansson wrote: > If the PSCI OSI mode isn't supported or fails to be enabled, the PM domain > topology with the genpd providers isn't initialized. This is perfectly fine > from cpuidle-psci point of view. > > However, since the PM domain topology in the DTS files is a description of > the HW, no matter of whether the PSCI OSI mode is supported or not, other > consumers besides the CPUs may rely on it. > > Therefore, let's always allow the initialization of the PM domain topology > to succeed, independently of whether the PSCI OSI mode is supported. > Consequentially we need to track if we succeed to enable the OSI mode, as > to know when a domain idlestate can be selected. > > Note that, CPU devices are still not being attached to the PM domain > topology, unless the PSCI OSI mode is supported. > > Signed-off-by: Ulf Hansson > --- > > Changes in v2: > - Assign the genpd ->power_off() callback, only when the PSCI OSI mode > has been successfully enabled. > > --- > drivers/cpuidle/cpuidle-psci-domain.c | 57 ++++++++++++++------------- > 1 file changed, 29 insertions(+), 28 deletions(-) > > diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c > index b6ab0415f450..256e7e35b5af 100644 > --- a/drivers/cpuidle/cpuidle-psci-domain.c > +++ b/drivers/cpuidle/cpuidle-psci-domain.c > @@ -105,7 +105,7 @@ static void psci_pd_free_states(struct genpd_power_state *states, > kfree(states); > } > > -static int psci_pd_init(struct device_node *np) > +static int psci_pd_init(struct device_node *np, bool use_osi) > { > struct generic_pm_domain *pd; > struct psci_pd_provider *pd_provider; > @@ -135,11 +135,14 @@ static int psci_pd_init(struct device_node *np) > > pd->free_states = psci_pd_free_states; > pd->name = kbasename(pd->name); > - pd->power_off = psci_pd_power_off; > pd->states = states; > pd->state_count = state_count; > pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN; > > + /* Use the ->power_off() callback when OSI is enabled. */ IIUC, you did mention that we need to attach PD even when the OSI fails as this could be shared domain. With the below conditional assignment of power_off, I understand that if OSI fails and we have domains attached, then it will be always ON ? Other than that, this patch looks good. Acked-by: Sudeep Holla -- Regards, Sudeep