From patchwork Thu Mar 20 12:11:00 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gautham R Shenoy X-Patchwork-Id: 3865521 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id ED63FBF540 for ; Thu, 20 Mar 2014 12:11:49 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1B20F20240 for ; Thu, 20 Mar 2014 12:11:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D19792024C for ; Thu, 20 Mar 2014 12:11:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757213AbaCTMLr (ORCPT ); Thu, 20 Mar 2014 08:11:47 -0400 Received: from e23smtp02.au.ibm.com ([202.81.31.144]:60656 "EHLO e23smtp02.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757211AbaCTMLq (ORCPT ); Thu, 20 Mar 2014 08:11:46 -0400 Received: from /spool/local by e23smtp02.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Thu, 20 Mar 2014 22:11:43 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 5D2A03578055 for ; Thu, 20 Mar 2014 23:11:13 +1100 (EST) Received: from d23av01.au.ibm.com (d23av01.au.ibm.com [9.190.234.96]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s2KCAx3211993504 for ; Thu, 20 Mar 2014 23:10:59 +1100 Received: from d23av01.au.ibm.com (localhost [127.0.0.1]) by d23av01.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s2KCBCXZ004168 for ; Thu, 20 Mar 2014 23:11:13 +1100 Received: from sofia.in.ibm.com (sofia.in.ibm.com [9.124.35.168]) by d23av01.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id s2KCB2Mt003964; Thu, 20 Mar 2014 23:11:11 +1100 From: "Gautham R. Shenoy" To: linuxppc-dev@ozlabs.org, linux-pm@vger.kernel.org Cc: benh@kernel.crashing.org, svaidy@linux.vnet.ibm.com, "Gautham R. Shenoy" Subject: [PATCH v3 5/5] powernv:cpufreq: Implement the driver->get() method Date: Thu, 20 Mar 2014 17:41:00 +0530 Message-Id: <1395317460-14811-6-git-send-email-ego@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1395317460-14811-1-git-send-email-ego@linux.vnet.ibm.com> References: <1395317460-14811-1-git-send-email-ego@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14032012-5490-0000-0000-0000053676F2 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Gautham R. Shenoy" The current frequency of a cpu is reported through the sysfs file cpuinfo_cur_freq. This requires the driver to implement a "->get(unsigned int cpu)" method which will return the current operating frequency. Implement a function named powernv_cpufreq_get() which reads the local pstate from the PMSR and returns the corresponding frequency. Set the powernv_cpufreq_driver.get hook to powernv_cpufreq_get(). Signed-off-by: Gautham R. Shenoy --- drivers/cpufreq/powernv-cpufreq.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 46bee8a..ef6ed8c 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -206,6 +206,43 @@ static inline void set_pmspr(unsigned long sprn, unsigned long val) BUG(); } +/* + * Computes the current frequency on this cpu + * and stores the result in *ret_freq. + */ +static void powernv_read_cpu_freq(void *ret_freq) +{ + unsigned long pmspr_val; + s8 local_pstate_id; + int *cur_freq, freq, pstate_id; + + cur_freq = (int *)ret_freq; + pmspr_val = get_pmspr(SPRN_PMSR); + + /* The local pstate id corresponds bits 48..55 in the PMSR. + * Note: Watch out for the sign! */ + local_pstate_id = (pmspr_val >> 48) & 0xFF; + pstate_id = local_pstate_id; + + freq = pstate_id_to_freq(pstate_id); + pr_debug("cpu %d pmsr %lx pstate_id %d frequency %d \n", + smp_processor_id(), pmspr_val, pstate_id, freq); + *cur_freq = freq; +} + +/* + * Returns the cpu frequency as reported by the firmware for 'cpu'. + * This value is reported through the sysfs file cpuinfo_cur_freq. + */ +unsigned int powernv_cpufreq_get(unsigned int cpu) +{ + int ret_freq; + + smp_call_function_any(cpu_sibling_mask(cpu), powernv_read_cpu_freq, + &ret_freq, 1); + return ret_freq; +} + static void set_pstate(void *pstate) { unsigned long val; @@ -297,6 +334,7 @@ static int powernv_cpufreq_target(struct cpufreq_policy *policy, static struct cpufreq_driver powernv_cpufreq_driver = { .verify = powernv_cpufreq_verify, .target = powernv_cpufreq_target, + .get = powernv_cpufreq_get, .init = powernv_cpufreq_cpu_init, .exit = powernv_cpufreq_cpu_exit, .name = "powernv-cpufreq",