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=-8.2 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 6567BC2D0C0 for ; Thu, 19 Dec 2019 14:34:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46AA024672 for ; Thu, 19 Dec 2019 14:34:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726891AbfLSOec (ORCPT ); Thu, 19 Dec 2019 09:34:32 -0500 Received: from foss.arm.com ([217.140.110.172]:39490 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726947AbfLSOec (ORCPT ); Thu, 19 Dec 2019 09:34:32 -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 7907931B; Thu, 19 Dec 2019 06:34:31 -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 7E8A83F6CF; Thu, 19 Dec 2019 06:34:29 -0800 (PST) Date: Thu, 19 Dec 2019 14:34:27 +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 , Kevin Hilman , Sudeep Holla , linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v4 13/14] cpuidle: psci: Add support for PM domains by using genpd Message-ID: <20191219143427.GF20746@bogus> References: <20191211154343.29765-1-ulf.hansson@linaro.org> <20191211154343.29765-14-ulf.hansson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191211154343.29765-14-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 Wed, Dec 11, 2019 at 04:43:42PM +0100, Ulf Hansson wrote: > When the hierarchical CPU topology layout is used in DT and the PSCI OSI > mode is supported by the PSCI FW, let's initialize a corresponding PM > domain topology by using genpd. This enables a CPU and a group of CPUs, > when attached to the topology, to be power-managed accordingly. > > To trigger the attempt to initialize the genpd data structures let's use a > subsys_initcall, which should be early enough to allow CPUs, but also other > devices to be attached. > > The initialization consists of parsing the PSCI OF node for the topology > and the "domain idle states" DT bindings. In case the idle states are > compatible with "domain-idle-state", the initialized genpd becomes > responsible of selecting an idle state for the PM domain, via assigning it > a genpd governor. > > Note that, a successful initialization of the genpd data structures, is > followed by a call to psci_set_osi_mode(), as to try to enable the OSI mode > in the PSCI FW. In case this fails, we fall back into a degraded mode > rather than bailing out and returning an error code. > > Co-developed-by: Lina Iyer > Signed-off-by: Lina Iyer > Signed-off-by: Ulf Hansson > --- > > Changes in v4: > - None. > > --- > drivers/cpuidle/cpuidle-psci-domain.c | 267 ++++++++++++++++++++++++++ > drivers/cpuidle/cpuidle-psci.c | 4 +- > drivers/cpuidle/cpuidle-psci.h | 5 + > 3 files changed, 274 insertions(+), 2 deletions(-) > > diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c > index 656ef3d59149..c2f94ba42222 100644 > --- a/drivers/cpuidle/cpuidle-psci-domain.c > +++ b/drivers/cpuidle/cpuidle-psci-domain.c > @@ -7,14 +7,281 @@ > * > */ > > +#define pr_fmt(fmt) "CPUidle PSCI: " fmt > + > #include > #include > #include > #include > #include > +#include > +#include > +#include > > #include "cpuidle-psci.h" > > +struct psci_pd_provider { > + struct list_head link; > + struct device_node *node; > +}; > + > +static LIST_HEAD(psci_pd_providers); > +static bool osi_mode_enabled; > + > +static int psci_pd_power_off(struct generic_pm_domain *pd) > +{ > + struct genpd_power_state *state = &pd->states[pd->state_idx]; > + u32 *pd_state; > + > + /* If we have failed to enable OSI mode, then abort power off. */ > + if (!osi_mode_enabled) > + return -EBUSY; > + Why is above check needed ? Shouldn't we have disable/remove pd of OSI is not enabled ? > + if (!state->data) > + return 0; > + > + /* OSI mode is enabled, set the corresponding domain state. */ > + pd_state = state->data; > + psci_set_domain_state(*pd_state); > + > + return 0; > +} > + [...] > +static const struct of_device_id psci_of_match[] __initconst = { > + { .compatible = "arm,psci" }, I think we can drop the above one as it's for v0.1 which didn't support OSI. > + { .compatible = "arm,psci-0.2" }, > + { .compatible = "arm,psci-1.0" }, > + {} > +}; > + > +static int __init psci_idle_init_domains(void) > +{ > + struct device_node *np = of_find_matching_node(NULL, psci_of_match); > + struct device_node *node; > + int ret = 0, pd_count = 0; > + > + if (!np) > + return -ENODEV; > + > + /* Currently limit the hierarchical topology to be used in OSI mode. */ > + if (!psci_has_osi_support()) > + goto out; > + > + /* > + * Parse child nodes for the "#power-domain-cells" property and > + * initialize a genpd/genpd-of-provider pair when it's found. > + */ > + for_each_child_of_node(np, node) { > + if (!of_find_property(node, "#power-domain-cells", NULL)) > + continue; > + > + ret = psci_pd_init(node); > + if (ret) > + goto put_node; > + > + pd_count++; > + } > + > + /* Bail out if not using the hierarchical CPU topology. */ > + if (!pd_count) > + goto out; > + > + /* Link genpd masters/subdomains to model the CPU topology. */ > + ret = psci_pd_init_topology(np); > + if (ret) > + goto remove_pd; > + > + /* Try to enable OSI mode. */ > + ret = psci_set_osi_mode(); > + if (ret) > + pr_warn("failed to enable OSI mode: %d\n", ret); Same question as above: shouldn't we disable and goto remove_pd ? -- Regards, Sudeep