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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 7A0E2C2D0D3 for ; Mon, 30 Dec 2019 16:35:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 561E120718 for ; Mon, 30 Dec 2019 16:35:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727217AbfL3QfL (ORCPT ); Mon, 30 Dec 2019 11:35:11 -0500 Received: from foss.arm.com ([217.140.110.172]:56426 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726597AbfL3QfL (ORCPT ); Mon, 30 Dec 2019 11:35:11 -0500 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 72C4631B; Mon, 30 Dec 2019 08:35:10 -0800 (PST) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 77BCB3F703; Mon, 30 Dec 2019 08:35:08 -0800 (PST) Date: Mon, 30 Dec 2019 16:35:03 +0000 From: Sudeep Holla To: Ulf Hansson Cc: Lorenzo Pieralisi , Rob Herring , linux-pm@vger.kernel.org, "Rafael J . Wysocki" , Daniel Lezcano , Mark Rutland , Lina Iyer , Vincent Guittot , Stephen Boyd , Andy Gross , Bjorn Andersson , Sudeep Holla , Kevin Hilman , linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v5 10/15] cpuidle: psci: Prepare to use OS initiated suspend mode via PM domains Message-ID: <20191230163503.GA16256@bogus> References: <20191230144402.30195-1-ulf.hansson@linaro.org> <20191230144402.30195-11-ulf.hansson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191230144402.30195-11-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 Mon, Dec 30, 2019 at 03:43:57PM +0100, Ulf Hansson wrote: > The per CPU variable psci_power_state, contains an array of fixed values, > which reflects the corresponding arm,psci-suspend-param parsed from DT, for > each of the available CPU idle states. > > This isn't sufficient when using the hierarchical CPU topology in DT, in > combination with having PSCI OS initiated (OSI) mode enabled. More > precisely, in OSI mode, Linux is responsible of telling the PSCI FW what > idle state the cluster (a group of CPUs) should enter, while in PSCI > Platform Coordinated (PC) mode, each CPU independently votes for an idle > state of the cluster. > > For this reason, introduce a per CPU variable called domain_state and > implement two helper functions to read/write its value. Then let the > domain_state take precedence over the regular selected state, when entering > and idle state. > > To avoid executing the above OSI specific code in the ->enter() callback, > while operating in the default PSCI Platform Coordinated mode, let's also > add a new enter-function and use it for OSI. > > Co-developed-by: Lina Iyer > Signed-off-by: Lina Iyer > Signed-off-by: Ulf Hansson > --- > > Changes in v5: > - None. > > --- > drivers/cpuidle/cpuidle-psci.c | 56 ++++++++++++++++++++++++++++++---- > 1 file changed, 50 insertions(+), 6 deletions(-) > > diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c > index 6a87848be3c3..9600fe674a89 100644 > --- a/drivers/cpuidle/cpuidle-psci.c > +++ b/drivers/cpuidle/cpuidle-psci.c > @@ -29,14 +29,47 @@ struct psci_cpuidle_data { > }; > > static DEFINE_PER_CPU_READ_MOSTLY(struct psci_cpuidle_data, psci_cpuidle_data); > +static DEFINE_PER_CPU(u32, domain_state); > + > +static inline void psci_set_domain_state(u32 state) > +{ > + __this_cpu_write(domain_state, state); > +} > + > +static inline u32 psci_get_domain_state(void) > +{ > + return __this_cpu_read(domain_state); > +} > + > +static inline int psci_enter_state(int idx, u32 state) > +{ > + return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, idx, state); > +} > + > +static int psci_enter_domain_idle_state(struct cpuidle_device *dev, > + struct cpuidle_driver *drv, int idx) > +{ > + struct psci_cpuidle_data *data = this_cpu_ptr(&psci_cpuidle_data); > + u32 *states = data->psci_states; > + u32 state = psci_get_domain_state(); > + int ret; > + > + if (!state) > + state = states[idx]; > + > + ret = psci_enter_state(idx, state); > + > + /* Clear the domain state to start fresh when back from idle. */ > + psci_set_domain_state(0); > + return ret; > +} > > static int psci_enter_idle_state(struct cpuidle_device *dev, > struct cpuidle_driver *drv, int idx) > { > u32 *state = __this_cpu_read(psci_cpuidle_data.psci_states); > > - return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, > - idx, state[idx]); > + return psci_enter_state(idx, state[idx]); > } > > static struct cpuidle_driver psci_idle_driver __initdata = { > @@ -79,7 +112,8 @@ static int __init psci_dt_parse_state_node(struct device_node *np, u32 *state) > return 0; > } > > -static int __init psci_dt_cpu_init_idle(struct device_node *cpu_node, > +static int __init psci_dt_cpu_init_idle(struct cpuidle_driver *drv, > + struct device_node *cpu_node, > unsigned int state_count, int cpu) > { > int i, ret = 0; > @@ -118,6 +152,15 @@ static int __init psci_dt_cpu_init_idle(struct device_node *cpu_node, > ret = PTR_ERR(data->dev); > goto free_mem; > } > + > + /* > + * Using the deepest state for the CPU to trigger a potential > + * selection of a shared state for the domain, assumes the > + * domain states are all deeper states. > + */ > + if (data->dev) Do we still need this check ? I thought we won't attach genpd if OSI is not enabled. If possible, please drop the check. Other than that, looks good to me. Reviewed-by: Sudeep Holla -- Regards, Sudeep