From patchwork Thu Jan 14 12:40:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Pali_Roh=C3=A1r?= X-Patchwork-Id: 12019423 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=-22.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 17C2DC433E9 for ; Thu, 14 Jan 2021 12:42:56 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CBC11239FD for ; Thu, 14 Jan 2021 12:42:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CBC11239FD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=n/GuvIOJNyRLu92V8yrA01+M7XzR2ZI9m2eE2QISqAk=; b=t2nYS8aekNOmQ2Wx1NMHhiAzH 5vFAo5a+QrmR6o1LYQCj6PSVu12tSM1zYHiS7n/eikFXsIzs9WKc7sTQLeL6pGZHmLsAyFJcW1E0T dZ83GBMfS8xtHDBuTb3dTxfUHR8v2uebKdyrGbWxkD+70xJpSlh17p5ZjwU4FD3lXaWXLmo3PL0rj EFQQ2KEfOzar+vU6LYPc7RZwD2QPPshAiE7lOB4zYiwupraiPCECMGrM/+kA6DYZy+Bz2SGp3r8Pq cu1Lk3yhd2HmSPfyHzjsVjoD1brPsJOTcIyxaUD5SJFnKJOoj2fUh1bpUBTvfFk9+DGUwLEgPoWvt uThnn0lsA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l01w2-0001ip-PL; Thu, 14 Jan 2021 12:41:06 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l01vs-0001fH-8m for linux-arm-kernel@lists.infradead.org; Thu, 14 Jan 2021 12:40:58 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2A14A23A57; Thu, 14 Jan 2021 12:40:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1610628055; bh=YkOKDLNCBPwojBLyeWcbId+gm+N8mW6chmEkVygO2ME=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SU4O4fCGB9WqZsSK7fXE59VQISGJkx/UkV+rRvFT8Og8tyiqyJNif0mHC2IRwRLIw LVboZuY5sSIVhiRPHj4tU8UHyvZT5TezsWWdVzlF+CDV0DN0W902qgKBlse4WYResG UXfIiW7JbYmiXWe95mvOQB2PxtpVBSPctgYgUTqlQmRiOWyQB9wvSvR61DxZ5kvMZ7 1JkUuouuG9WLjdt4kyhBYH4js7JWgvZawMnSubswn6vVKgi9a31DbBxE8DUai/Qqk9 4kThi0IWLj/P/Hu2tOxM7ppmAuUHHN+d9CZ1bCnrDA6b9su+85Pt5RyT38NWAOVK8h KA0YUIRNbQE9A== Received: by pali.im (Postfix) id 4B4077C1; Thu, 14 Jan 2021 13:40:53 +0100 (CET) From: =?utf-8?q?Pali_Roh=C3=A1r?= To: Gregory Clement , Andrew Lunn , Michael Turquette , Stephen Boyd , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org Subject: [PATCH mvebu v2 02/10] cpufreq: armada-37xx: Fix setting TBG parent for load levels Date: Thu, 14 Jan 2021 13:40:24 +0100 Message-Id: <20210114124032.12765-3-pali@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210114124032.12765-1-pali@kernel.org> References: <20210114124032.12765-1-pali@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210114_074056_555499_917A58FB X-CRM114-Status: GOOD ( 22.18 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?utf-8?q?Marek_Beh=C3=BAn?= , Tomasz Maciej Nowak , Luka Perkov , Andre Heider , Vladimir Vid , Russell King , =?utf-8?q?G=C3=A9rald_Kerma?= , Miquel Raynal , Konstantin Porotchkin Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Marek Behún With CPU frequency determining software [1] we have discovered that after this driver does one CPU frequency change, the base frequency of the CPU is set to the frequency of TBG-A-P clock, instead of the TBG that is parent to the CPU. This can be reproduced on EspressoBIN and Turris MOX: cd /sys/devices/system/cpu/cpufreq/policy0 echo powersave >scaling_governor echo performance >scaling_governor Running the mhz tool before this driver is loaded reports 1000 MHz, and after loading the driver and executing commands above the tool reports 800 MHz. The change of TBG clock selector is supposed to happen in function armada37xx_cpufreq_dvfs_setup. Before the function returns, it does this: parent = clk_get_parent(clk); clk_set_parent(clk, parent); The armada-37xx-periph clock driver has the .set_parent method implemented correctly for this, so if the method was actually called, this would work. But since the introduction of the common clock framework in commit b2476490ef11 ("clk: introduce the common clock..."), the clk_set_parent function checks whether the parent is actually changing, and if the requested new parent is same as the old parent (which is obviously the case for the code above), the .set_parent method is not called at all. This patch fixes this issue by filling the correct TBG clock selector directly in the armada37xx_cpufreq_dvfs_setup during the filling of other registers at the same address. But the determination of CPU TBG index cannot be done via the common clock framework, therefore we need to access the North Bridge Peripheral Clock registers directly in this driver. [1] https://github.com/wtarreau/mhz Signed-off-by: Marek Behún Fixes: 92ce45fb875d ("cpufreq: Add DVFS support for Armada 37xx") Cc: stable@vger.kernel.org Cc: Gregory CLEMENT Cc: Miquel Raynal --- drivers/cpufreq/armada-37xx-cpufreq.c | 35 ++++++++++++++++++--------- 1 file changed, 23 insertions(+), 12 deletions(-) diff --git a/drivers/cpufreq/armada-37xx-cpufreq.c b/drivers/cpufreq/armada-37xx-cpufreq.c index b4af4094309b..b8dc6c849579 100644 --- a/drivers/cpufreq/armada-37xx-cpufreq.c +++ b/drivers/cpufreq/armada-37xx-cpufreq.c @@ -25,6 +25,10 @@ #include "cpufreq-dt.h" +/* Clk register set */ +#define ARMADA_37XX_CLK_TBG_SEL 0 +#define ARMADA_37XX_CLK_TBG_SEL_CPU_OFF 22 + /* Power management in North Bridge register set */ #define ARMADA_37XX_NB_L0L1 0x18 #define ARMADA_37XX_NB_L2L3 0x1C @@ -120,10 +124,15 @@ static struct armada_37xx_dvfs *armada_37xx_cpu_freq_info_get(u32 freq) * will be configured then the DVFS will be enabled. */ static void __init armada37xx_cpufreq_dvfs_setup(struct regmap *base, - struct clk *clk, u8 *divider) + struct regmap *clk_base, u8 *divider) { + u32 cpu_tbg_sel; int load_lvl; - struct clk *parent; + + /* Determine to which TBG clock is CPU connected */ + regmap_read(clk_base, ARMADA_37XX_CLK_TBG_SEL, &cpu_tbg_sel); + cpu_tbg_sel >>= ARMADA_37XX_CLK_TBG_SEL_CPU_OFF; + cpu_tbg_sel &= ARMADA_37XX_NB_TBG_SEL_MASK; for (load_lvl = 0; load_lvl < LOAD_LEVEL_NR; load_lvl++) { unsigned int reg, mask, val, offset = 0; @@ -142,6 +151,11 @@ static void __init armada37xx_cpufreq_dvfs_setup(struct regmap *base, mask = (ARMADA_37XX_NB_CLK_SEL_MASK << ARMADA_37XX_NB_CLK_SEL_OFF); + /* Set TBG index, for all levels we use the same TBG */ + val = cpu_tbg_sel << ARMADA_37XX_NB_TBG_SEL_OFF; + mask = (ARMADA_37XX_NB_TBG_SEL_MASK + << ARMADA_37XX_NB_TBG_SEL_OFF); + /* * Set cpu divider based on the pre-computed array in * order to have balanced step. @@ -160,14 +174,6 @@ static void __init armada37xx_cpufreq_dvfs_setup(struct regmap *base, regmap_update_bits(base, reg, mask, val); } - - /* - * Set cpu clock source, for all the level we keep the same - * clock source that the one already configured. For this one - * we need to use the clock framework - */ - parent = clk_get_parent(clk); - clk_set_parent(clk, parent); } /* @@ -358,11 +364,16 @@ static int __init armada37xx_cpufreq_driver_init(void) struct platform_device *pdev; unsigned long freq; unsigned int cur_frequency, base_frequency; - struct regmap *nb_pm_base, *avs_base; + struct regmap *nb_clk_base, *nb_pm_base, *avs_base; struct device *cpu_dev; int load_lvl, ret; struct clk *clk, *parent; + nb_clk_base = + syscon_regmap_lookup_by_compatible("marvell,armada-3700-periph-clock-nb"); + if (IS_ERR(nb_clk_base)) + return -ENODEV; + nb_pm_base = syscon_regmap_lookup_by_compatible("marvell,armada-3700-nb-pm"); @@ -439,7 +450,7 @@ static int __init armada37xx_cpufreq_driver_init(void) armada37xx_cpufreq_avs_configure(avs_base, dvfs); armada37xx_cpufreq_avs_setup(avs_base, dvfs); - armada37xx_cpufreq_dvfs_setup(nb_pm_base, clk, dvfs->divider); + armada37xx_cpufreq_dvfs_setup(nb_pm_base, nb_clk_base, dvfs->divider); clk_put(clk); for (load_lvl = ARMADA_37XX_DVFS_LOAD_0; load_lvl < LOAD_LEVEL_NR;