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=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 8F64EC432C3 for ; Fri, 15 Nov 2019 17:13:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B9FC20728 for ; Fri, 15 Nov 2019 17:13:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727585AbfKORNm (ORCPT ); Fri, 15 Nov 2019 12:13:42 -0500 Received: from foss.arm.com ([217.140.110.172]:34036 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727567AbfKORNl (ORCPT ); Fri, 15 Nov 2019 12:13:41 -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 D726531B; Fri, 15 Nov 2019 09:13:40 -0800 (PST) Received: from bogus (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D05C03F6C4; Fri, 15 Nov 2019 09:13:38 -0800 (PST) Date: Fri, 15 Nov 2019 17:13:36 +0000 From: Sudeep Holla To: Ulf Hansson Cc: "Rafael J . Wysocki" , Daniel Lezcano , Lorenzo Pieralisi , Mark Rutland , Lina Iyer , linux-pm@vger.kernel.org, Rob Herring , 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 v2 08/13] cpuidle: psci: Add a helper to attach a CPU to its PM domain Message-ID: <20191115171336.GC27170@bogus> References: <20191029164438.17012-1-ulf.hansson@linaro.org> <20191029164438.17012-9-ulf.hansson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191029164438.17012-9-ulf.hansson@linaro.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Tue, Oct 29, 2019 at 05:44:33PM +0100, Ulf Hansson wrote: > Introduce a PSCI DT helper function, psci_dt_attach_cpu(), which takes a > CPU number as an in-parameter and tries to attach the CPU's struct device > to its corresponding PM domain. > > Let's makes use of dev_pm_domain_attach_by_name(), as it allows us to > specify "psci" as the "name" of the PM domain to attach to. Additionally, > let's also prepare the attached device to be power managed via runtime PM. > > Note that, the implementation of the new helper function is in a new > separate c-file, which may seems a bit too much at this point. However, > subsequent changes that implements the remaining part of the PM domain > support for cpuidle-psci, helps to justify this split. > > Signed-off-by: Ulf Hansson > --- > > Changes in v2: > - Reorder patch to be the first one that starts adding the PM domain > support. > - Rebased. > > --- > drivers/cpuidle/Makefile | 4 ++- > drivers/cpuidle/cpuidle-psci-domain.c | 36 +++++++++++++++++++++++++++ > drivers/cpuidle/cpuidle-psci.h | 12 +++++++++ > 3 files changed, 51 insertions(+), 1 deletion(-) > create mode 100644 drivers/cpuidle/cpuidle-psci-domain.c > create mode 100644 drivers/cpuidle/cpuidle-psci.h > > diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile > index ee70d5cc5b99..cc8c769d7fa9 100644 > --- a/drivers/cpuidle/Makefile > +++ b/drivers/cpuidle/Makefile > @@ -21,7 +21,9 @@ obj-$(CONFIG_ARM_U8500_CPUIDLE) += cpuidle-ux500.o > obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o > obj-$(CONFIG_ARM_EXYNOS_CPUIDLE) += cpuidle-exynos.o > obj-$(CONFIG_ARM_CPUIDLE) += cpuidle-arm.o > -obj-$(CONFIG_ARM_PSCI_CPUIDLE) += cpuidle-psci.o > +obj-$(CONFIG_ARM_PSCI_CPUIDLE) += cpuidle_psci.o > +cpuidle_psci-y := cpuidle-psci.o > +cpuidle_psci-$(CONFIG_PM_GENERIC_DOMAINS_OF) += cpuidle-psci-domain.o This was super confusing for a minute until I noticed the difference between _ and - used here. I know such pattern is used in the kernel, just that it's difficult to notice on first go :) > > ############################################################################### > # MIPS drivers > diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c > new file mode 100644 > index 000000000000..bc7df4dc0686 > --- /dev/null > +++ b/drivers/cpuidle/cpuidle-psci-domain.c > @@ -0,0 +1,36 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * PM domains for CPUs via genpd - managed by cpuidle-psci. > + * > + * Copyright (C) 2019 Linaro Ltd. > + * Author: Ulf Hansson > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include "cpuidle-psci.h" > + > +struct device *psci_dt_attach_cpu(int cpu) > +{ > + struct device *dev; > + > + /* Currently limit the hierarchical topology to be used in OSI mode. */ > + if (!psci_has_osi_support()) > + return NULL; > + > + dev = dev_pm_domain_attach_by_name(get_cpu_device(cpu), "psci"); > + if (IS_ERR_OR_NULL(dev)) > + return dev; > + > + pm_runtime_irq_safe(dev); > + if (cpu_online(cpu)) > + pm_runtime_get_sync(dev); I probably have to wait till I see the user of this, but until then I assume we have some way to deal with CPU HP machinery for this. Other than that, it looks fine. I will get back to this to ack or with more questions as I review further. -- Regards, Sudeep