From patchwork Wed Oct 14 09:36:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sumit Gupta X-Patchwork-Id: 269744 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=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 7B7D6C43457 for ; Wed, 14 Oct 2020 09:36:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 18E8821D81 for ; Wed, 14 Oct 2020 09:36:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="I9hRcMpX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726452AbgJNJgX (ORCPT ); Wed, 14 Oct 2020 05:36:23 -0400 Received: from hqnvemgate26.nvidia.com ([216.228.121.65]:6440 "EHLO hqnvemgate26.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725960AbgJNJgX (ORCPT ); Wed, 14 Oct 2020 05:36:23 -0400 Received: from hqmail.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate26.nvidia.com (using TLS: TLSv1.2, AES256-SHA) id ; Wed, 14 Oct 2020 02:36:09 -0700 Received: from HQMAIL109.nvidia.com (172.20.187.15) by HQMAIL109.nvidia.com (172.20.187.15) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Wed, 14 Oct 2020 09:36:18 +0000 Received: from sumitg-l4t.nvidia.com (172.20.13.39) by mail.nvidia.com (172.20.187.15) with Microsoft SMTP Server id 15.0.1473.3 via Frontend Transport; Wed, 14 Oct 2020 09:36:15 +0000 From: Sumit Gupta To: , , , , , , , , CC: , , Subject: [PATCH v3] cpufreq: tegra194: get consistent cpuinfo_cur_freq Date: Wed, 14 Oct 2020 15:06:11 +0530 Message-ID: <1602668171-30104-1-git-send-email-sumitg@nvidia.com> X-Mailer: git-send-email 2.7.4 X-NVConfidentiality: public MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1602668169; bh=nJXHQmA8SJehW7u27ymHyIMfAp9QzF0a30R0l0W0ccY=; h=From:To:CC:Subject:Date:Message-ID:X-Mailer:X-NVConfidentiality: MIME-Version:Content-Type; b=I9hRcMpXYVEMOYPv3b65uisktBZmMlkA1NAwI6Rsi5F8yQWTLcqGa8HZXFw2jfwcN KRZvsk+toi82mkENMo6imd3A+E9HskH2np3Dr/+/YVZlNuJf/fHRz9Vnaszsh+KbQx 1LKATsBjfGJLRwtqbmE3Xx2OnhWyys2oX8bJ/6jJNhMcOkLPmlPzdgJvoZlbzwgZFj k8CaJgRBDjI8r190U6IpBeYt4MotlQ401n2sU5OBf6LyHOTglRlWXc7jnJ23Xen5CN xpLKly1Yu2YBEMwN7EK3+CyFK5/f4vPmsetjqafSjlJWJWEEwE9p52Q0I0LBKC7W1c d+vuEO0A2r+Ig== Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Frequency returned by 'cpuinfo_cur_freq' using counters is not fixed and keeps changing slightly. This change returns a consistent value from freq_table. If the reconstructed frequency has acceptable delta from the last written value, then return the frequency corresponding to the last written ndiv value from freq_table. Otherwise, print a warning and return the reconstructed freq. Signed-off-by: Sumit Gupta --- Sending only this patch as other patch not required after the change to convert 'pr_warn' to 'pr_info' in cpufreq core for unlisted freq. Changelog v1[2] -> v3: - Removed unwanted checks for cpu_online and max cluster number - Used WARN_ON_ONCE to avoid print flooding. v1[1] -> v2: - Minor changes to improve comments and reduce debug prints. - Get freq table from cluster specific data instead of policy. [2] https://marc.info/?l=linux-tegra&m=160216218511280&w=2 [1] https://marc.info/?l=linux-arm-kernel&m=160028821117535&w=2 drivers/cpufreq/tegra194-cpufreq.c | 62 ++++++++++++++++++++++++++++++++------ 1 file changed, 53 insertions(+), 9 deletions(-) diff --git a/drivers/cpufreq/tegra194-cpufreq.c b/drivers/cpufreq/tegra194-cpufreq.c index e1d931c..7901587 100644 --- a/drivers/cpufreq/tegra194-cpufreq.c +++ b/drivers/cpufreq/tegra194-cpufreq.c @@ -180,9 +180,61 @@ static unsigned int tegra194_get_speed_common(u32 cpu, u32 delay) return (rate_mhz * KHZ); /* in KHz */ } +static void get_cpu_ndiv(void *ndiv) +{ + u64 ndiv_val; + + asm volatile("mrs %0, s3_0_c15_c0_4" : "=r" (ndiv_val) : ); + + *(u64 *)ndiv = ndiv_val; +} + +static void set_cpu_ndiv(void *data) +{ + struct cpufreq_frequency_table *tbl = data; + u64 ndiv_val = (u64)tbl->driver_data; + + asm volatile("msr s3_0_c15_c0_4, %0" : : "r" (ndiv_val)); +} + static unsigned int tegra194_get_speed(u32 cpu) { - return tegra194_get_speed_common(cpu, US_DELAY); + struct tegra194_cpufreq_data *data = cpufreq_get_driver_data(); + struct cpufreq_frequency_table *pos; + unsigned int rate; + u64 ndiv; + int ret; + u32 cl; + + smp_call_function_single(cpu, get_cpu_cluster, &cl, true); + + /* reconstruct actual cpu freq using counters */ + rate = tegra194_get_speed_common(cpu, US_DELAY); + + /* get last written ndiv value */ + ret = smp_call_function_single(cpu, get_cpu_ndiv, &ndiv, true); + if (WARN_ON_ONCE(ret)) + return rate; + + /* + * If the reconstructed frequency has acceptable delta from + * the last written value, then return freq corresponding + * to the last written ndiv value from freq_table. This is + * done to return consistent value. + */ + cpufreq_for_each_valid_entry(pos, data->tables[cl]) { + if (pos->driver_data != ndiv) + continue; + + if (abs(pos->frequency - rate) > 115200) { + pr_warn("cpufreq: cpu%d,cur:%u,set:%u,set ndiv:%llu\n", + cpu, rate, pos->frequency, ndiv); + } else { + rate = pos->frequency; + } + break; + } + return rate; } static int tegra194_cpufreq_init(struct cpufreq_policy *policy) @@ -209,14 +261,6 @@ static int tegra194_cpufreq_init(struct cpufreq_policy *policy) return 0; } -static void set_cpu_ndiv(void *data) -{ - struct cpufreq_frequency_table *tbl = data; - u64 ndiv_val = (u64)tbl->driver_data; - - asm volatile("msr s3_0_c15_c0_4, %0" : : "r" (ndiv_val)); -} - static int tegra194_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) {