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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 6F948C433DF for ; Thu, 21 May 2020 06:25:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4C2D320748 for ; Thu, 21 May 2020 06:25:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726938AbgEUGZi (ORCPT ); Thu, 21 May 2020 02:25:38 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:4831 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726506AbgEUGZi (ORCPT ); Thu, 21 May 2020 02:25:38 -0400 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 1BDDE98CBFABEE69D726; Thu, 21 May 2020 14:25:35 +0800 (CST) Received: from [127.0.0.1] (10.166.215.101) by DGGEMS409-HUB.china.huawei.com (10.3.19.209) with Microsoft SMTP Server id 14.3.487.0; Thu, 21 May 2020 14:25:26 +0800 Subject: Re: [RFC PATCH v3 2/2] CPPC: add support for SW BOOST To: Viresh Kumar CC: , , , , , , , , References: <1589888489-13828-1-git-send-email-wangxiongfeng2@huawei.com> <1589888489-13828-3-git-send-email-wangxiongfeng2@huawei.com> <20200520050014.qpnnmyas2z7mvcss@vireshk-i7> From: Xiongfeng Wang Message-ID: <161082be-0df8-0128-bc77-58aee8d43bf6@huawei.com> Date: Thu, 21 May 2020 14:25:26 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200520050014.qpnnmyas2z7mvcss@vireshk-i7> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.166.215.101] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Hi Viresh, On 2020/5/20 13:00, Viresh Kumar wrote: > On 19-05-20, 19:41, Xiongfeng Wang wrote: >> To add SW BOOST support for CPPC, we need to get the max frequency of >> boost mode and non-boost mode. ACPI spec 6.2 section 8.4.7.1 describe >> the following two CPC registers. >> >> "Highest performance is the absolute maximum performance an individual >> processor may reach, assuming ideal conditions. This performance level >> may not be sustainable for long durations, and may only be achievable if >> other platform components are in a specific state; for example, it may >> require other processors be in an idle state. >> >> Nominal Performance is the maximum sustained performance level of the >> processor, assuming ideal operating conditions. In absence of an >> external constraint (power, thermal, etc.) this is the performance level >> the platform is expected to be able to maintain continuously. All >> processors are expected to be able to sustain their nominal performance >> state simultaneously." >> >> To add SW BOOST support for CPPC, we can use Highest Performance as the >> max performance in boost mode and Nominal Performance as the max >> performance in non-boost mode. If the Highest Performance is greater >> than the Nominal Performance, we assume SW BOOST is supported. >> >> The current CPPC driver does not support SW BOOST and use 'Highest >> Performance' as the max performance the CPU can achieve. 'Nominal >> Performance' is used to convert 'performance' to 'frequency'. That >> means, if firmware enable boost and provide a value for Highest >> Performance which is greater than Nominal Performance, boost feature is >> enabled by default. >> >> Because SW BOOST is disabled by default, so, after this patch, boost >> feature is disabled by default even if boost is enabled by firmware. >> >> Signed-off-by: Xiongfeng Wang >> --- >> drivers/cpufreq/cppc_cpufreq.c | 39 +++++++++++++++++++++++++++++++++++++-- >> 1 file changed, 37 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c >> index bda0b24..792ed9e 100644 >> --- a/drivers/cpufreq/cppc_cpufreq.c >> +++ b/drivers/cpufreq/cppc_cpufreq.c >> @@ -37,6 +37,7 @@ >> * requested etc. >> */ >> static struct cppc_cpudata **all_cpu_data; >> +static bool boost_supported; >> >> struct cppc_workaround_oem_info { >> char oem_id[ACPI_OEM_ID_SIZE + 1]; >> @@ -310,7 +311,7 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) >> * Section 8.4.7.1.1.5 of ACPI 6.1 spec) >> */ >> policy->min = cppc_cpufreq_perf_to_khz(cpu, cpu->perf_caps.lowest_nonlinear_perf); >> - policy->max = cppc_cpufreq_perf_to_khz(cpu, cpu->perf_caps.highest_perf); >> + policy->max = cppc_cpufreq_perf_to_khz(cpu, cpu->perf_caps.nominal_perf); >> >> /* >> * Set cpuinfo.min_freq to Lowest to make the full range of performance >> @@ -318,7 +319,7 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) >> * nonlinear perf >> */ >> policy->cpuinfo.min_freq = cppc_cpufreq_perf_to_khz(cpu, cpu->perf_caps.lowest_perf); >> - policy->cpuinfo.max_freq = cppc_cpufreq_perf_to_khz(cpu, cpu->perf_caps.highest_perf); >> + policy->cpuinfo.max_freq = cppc_cpufreq_perf_to_khz(cpu, cpu->perf_caps.nominal_perf); >> >> policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu_num); >> policy->shared_type = cpu->shared_type; >> @@ -343,6 +344,13 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) >> >> cpu->cur_policy = policy; >> >> + /* >> + * If 'highest_perf' is greater than 'nominal_perf', we assume CPU Boost >> + * is supported. >> + */ >> + if (cpu->perf_caps.highest_perf > cpu->perf_caps.nominal_perf) >> + boost_supported = true; >> + >> /* Set policy->cur to max now. The governors will adjust later. */ >> policy->cur = cppc_cpufreq_perf_to_khz(cpu, >> cpu->perf_caps.highest_perf); >> @@ -410,6 +418,32 @@ static unsigned int cppc_cpufreq_get_rate(unsigned int cpunum) >> return cppc_get_rate_from_fbctrs(cpu, fb_ctrs_t0, fb_ctrs_t1); >> } >> >> +static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state) >> +{ >> + struct cppc_cpudata *cpudata; >> + int ret = 0; > > No need to initialize this. I will change it in the next version. Thanks for your advice. I will add your 'Suggested-by' for these two patches. Thanks, Xiongfeng > >> + >> + if (!boost_supported) { >> + pr_err("BOOST not supported by CPU or firmware\n"); >> + return -EINVAL; >> + } >> + >> + cpudata = all_cpu_data[policy->cpu]; >> + if (state) >> + policy->max = cppc_cpufreq_perf_to_khz(cpudata, >> + cpudata->perf_caps.highest_perf); >> + else >> + policy->max = cppc_cpufreq_perf_to_khz(cpudata, >> + cpudata->perf_caps.nominal_perf); >> + policy->cpuinfo.max_freq = policy->max; >> + >> + ret = freq_qos_update_request(policy->max_freq_req, policy->max); >> + if (ret < 0) >> + return ret; >> + >> + return 0; >> +} >> + >> static struct cpufreq_driver cppc_cpufreq_driver = { >> .flags = CPUFREQ_CONST_LOOPS, >> .verify = cppc_verify_policy, >> @@ -417,6 +451,7 @@ static unsigned int cppc_cpufreq_get_rate(unsigned int cpunum) >> .get = cppc_cpufreq_get_rate, >> .init = cppc_cpufreq_cpu_init, >> .stop_cpu = cppc_cpufreq_stop_cpu, >> + .set_boost = cppc_cpufreq_set_boost, >> .name = "cppc_cpufreq", >> }; >> >> -- >> 1.7.12.4 >