From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sudeep Holla Subject: [PATCH v6 20/20] cpufreq: scmi: add support for fast frequency switching Date: Fri, 23 Feb 2018 16:23:50 +0000 Message-ID: <1519403030-21189-21-git-send-email-sudeep.holla@arm.com> References: <1519403030-21189-1-git-send-email-sudeep.holla@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1519403030-21189-1-git-send-email-sudeep.holla@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: ALKML , LKML , DTML Cc: Alexey Klimov , linux-pm@vger.kernel.org, Greg Kroah-Hartman , Arnd Bergmann , Sudeep Holla List-Id: devicetree@vger.kernel.org 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: linux-pm@vger.kernel.org Acked-by: Rafael J. Wysocki Acked-by: Viresh Kumar Signed-off-by: Sudeep Holla --- drivers/cpufreq/scmi-cpufreq.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index 3745dc5fe2a8..ec0c58ddc1ed 100644 --- a/drivers/cpufreq/scmi-cpufreq.c +++ b/drivers/cpufreq/scmi-cpufreq.c @@ -69,6 +69,22 @@ scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) return ret; } +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 = handle->perf_ops; + + if (!perf_ops->freq_set(handle, priv->domain_id, + target_freq * 1000, true)) { + arch_set_freq_scale(policy->related_cpus, target_freq, + policy->cpuinfo.max_freq); + return target_freq; + } + + return 0; +} + static int scmi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask) { @@ -168,6 +184,7 @@ 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: @@ -206,6 +223,7 @@ static struct cpufreq_driver scmi_cpufreq_driver = { .verify = cpufreq_generic_frequency_table_verify, .attr = cpufreq_generic_attr, .target_index = scmi_cpufreq_set_target, + .fast_switch = scmi_cpufreq_fast_switch, .get = scmi_cpufreq_get_rate, .init = scmi_cpufreq_init, .exit = scmi_cpufreq_exit, -- 2.7.4