From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757279AbaCRRXm (ORCPT ); Tue, 18 Mar 2014 13:23:42 -0400 Received: from mail-pb0-f44.google.com ([209.85.160.44]:41866 "EHLO mail-pb0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757237AbaCRRWz (ORCPT ); Tue, 18 Mar 2014 13:22:55 -0400 From: dirk.brandewie@gmail.com To: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, rjw@rjwysocki.net, patrick.marlier@gmail.com, viresh.kumar@linaro.org, srivatsa.bhat@linux.vnet.ibm.com, dirk.brandewie@gmail.com, Dirk Brandewie Subject: [PATCH 1/2] cpufreq: Add stop callback to cpufreq_driver interface Date: Tue, 18 Mar 2014 10:22:40 -0700 Message-Id: <1395163361-26380-2-git-send-email-dirk.j.brandewie@intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1395163361-26380-1-git-send-email-dirk.j.brandewie@intel.com> References: <1394831037-15553-1-git-send-email-dirk.j.brandewie@intel.com> <1395163361-26380-1-git-send-email-dirk.j.brandewie@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dirk Brandewie This callback allows the driver to do clean up before the CPU is completely down and its state cannot be modified. This is used by the intel_pstate driver to reduce the requested P state prior to the core going away. This is required because the requested P state of the offline core is used to select the package P state. This effectively sets the floor package P state to the requested P state on the offline core. Signed-off-by: Dirk Brandewie --- Documentation/cpu-freq/cpu-drivers.txt | 8 +++++++- drivers/cpufreq/cpufreq.c | 3 ++- include/linux/cpufreq.h | 1 + 3 files changed, 10 insertions(+), 2 deletions(-) diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt index 8b1a445..79def80 100644 --- a/Documentation/cpu-freq/cpu-drivers.txt +++ b/Documentation/cpu-freq/cpu-drivers.txt @@ -61,7 +61,13 @@ target_index - See below on the differences. And optionally -cpufreq_driver.exit - A pointer to a per-CPU cleanup function. +cpufreq_driver.exit - A pointer to a per-CPU cleanup + function called during CPU_POST_DEAD + phase of cpu hotplug process. + +cpufreq_driver.stop - A pointer to a per-CPU stop function + called during CPU_DOWN_PREPARE phase of + cpu hotplug process. cpufreq_driver.resume - A pointer to a per-CPU resume function which is called with interrupts disabled diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index cf485d9..6e6beae 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1336,7 +1336,8 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, __func__, new_cpu, cpu); } } - } + } else if (cpufreq_driver->stop) + cpufreq_driver->stop(policy); return 0; } diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 4d89e0e..ff8db19 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -224,6 +224,7 @@ struct cpufreq_driver { int (*bios_limit) (int cpu, unsigned int *limit); int (*exit) (struct cpufreq_policy *policy); + int (*stop) (struct cpufreq_policy *policy); int (*suspend) (struct cpufreq_policy *policy); int (*resume) (struct cpufreq_policy *policy); struct freq_attr **attr; -- 1.8.3.1