Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752846AbdHDOcx (ORCPT ); Fri, 4 Aug 2017 10:32:53 -0400 Received: from foss.arm.com ([217.140.101.70]:54512 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752594AbdHDOcu (ORCPT ); Fri, 4 Aug 2017 10:32:50 -0400 From: Sudeep Holla To: ALKML , LKML , DTML Cc: Sudeep Holla , Roy Franz , Harb Abdulhamid , Nishanth Menon , Arnd Bergmann , Loc Ho , Alexey Klimov , Ryan Harkin , Jassi Brar , "Rafael J. Wysocki" , Viresh Kumar , linux-pm@vger.kernel.org Subject: [PATCH v2 18/18] cpufreq: scmi: add support for fast frequency switching Date: Fri, 4 Aug 2017 15:31:44 +0100 Message-Id: <1501857104-11279-19-git-send-email-sudeep.holla@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1501857104-11279-1-git-send-email-sudeep.holla@arm.com> References: <1501857104-11279-1-git-send-email-sudeep.holla@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2235 Lines: 65 The cpufreq core provides option for drivers to implement fast_switch callback which is invoked for frequency switching from interrupt context. This patch adds support for fast_switch callback in SCMI cpufreq driver by making use of polling based SCMI transfer. It also sets the flag fast_switch_possible. Cc: "Rafael J. Wysocki" Cc: Viresh Kumar Cc: linux-pm@vger.kernel.org Signed-off-by: Sudeep Holla --- drivers/cpufreq/scmi-cpufreq.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index 034359cafea5..cb1084cb1ef1 100644 --- a/drivers/cpufreq/scmi-cpufreq.c +++ b/drivers/cpufreq/scmi-cpufreq.c @@ -61,6 +61,19 @@ scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) return perf_ops->freq_set(priv->handle, priv->domain_id, freq, false); } +static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct scmi_data *priv = policy->driver_data; + struct scmi_perf_ops *perf_ops = priv->handle->perf_ops; + + if (!perf_ops->freq_set(priv->handle, priv->domain_id, + target_freq * 1000, true)) + return target_freq; + + return CPUFREQ_ENTRY_INVALID; +} + static int scmi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask) { @@ -164,6 +177,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) policy->cpuinfo.transition_latency = latency; + policy->fast_switch_possible = true; return 0; out_free_cpufreq_table: @@ -180,6 +194,7 @@ static int scmi_cpufreq_exit(struct cpufreq_policy *policy) { struct scmi_data *priv = policy->driver_data; + policy->fast_switch_possible = false; cpufreq_cooling_unregister(priv->cdev); dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table); dev_pm_opp_cpumask_remove_table(policy->related_cpus); @@ -228,6 +243,7 @@ static struct cpufreq_driver scmi_cpufreq_driver = { .init = scmi_cpufreq_init, .exit = scmi_cpufreq_exit, .ready = scmi_cpufreq_ready, + .fast_switch = scmi_cpufreq_fast_switch, }; static int scmi_cpufreq_probe(struct platform_device *pdev) -- 2.7.4