From patchwork Wed Jan 11 19:19:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Baryshkov X-Patchwork-Id: 641407 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00ED2C678D9 for ; Wed, 11 Jan 2023 19:20:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235532AbjAKTUb (ORCPT ); Wed, 11 Jan 2023 14:20:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34270 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232785AbjAKTUO (ORCPT ); Wed, 11 Jan 2023 14:20:14 -0500 Received: from mail-lj1-x232.google.com (mail-lj1-x232.google.com [IPv6:2a00:1450:4864:20::232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1CD82164BC for ; Wed, 11 Jan 2023 11:20:13 -0800 (PST) Received: by mail-lj1-x232.google.com with SMTP id bx6so17090971ljb.3 for ; Wed, 11 Jan 2023 11:20:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=lRtL6Eef4RVgyfHAkdoUF1I7EUT/FswJ9g5onTCIfoQ=; b=hhLFIE8mcq9jQntC6JKJYrzOWorc0tkPXXeghVqmKf+tK5KMecdQlacVW8jxqIPNXk Dcq7j5q602MMahelnW0Lb/bjS75CR/MCOZJSs5YbB8ARelab8Rn3I8AnW3IZXqJLkzM0 aspaywfNlRnqT3laWvposvhfro0C+z8X7iMlXbR9IleaAMGKN4pZjIKK/fVPSuwYvrUL 7P1ihnx2J5ECEnyPO/H/95tzaWN/ec5eABaXBtuZOTSM4RHdV4XxR1zje6xGJiUocJTG NUGf6U7A/Ywf9Uvb4DewL0FTdUQdWNUCfpWZuFqcfjkynNjmMO+PZNwEcMOGmvQ68M+V URtA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lRtL6Eef4RVgyfHAkdoUF1I7EUT/FswJ9g5onTCIfoQ=; b=KyYOPnsPAgq3oMW5aCKqJiArcoeOiBn7El2aHLIt/GtP9TUIv4b8cGNmVdWfEQ3Fd7 x5IpDpCr3PXrohgxCcU+kUPy71ArlNMbILQnBHV0PcyfoBVd/J2QVmAng2vcX9oSbscg 5kttPSDo03tviAYGgCiNyT+t3vW4RBYJEuVsc/RGRBhGesD4uwpxf70YYXqpy93WXK3N vrv+uIRwCgK9NGrbCF9CtrPil95TccJthVcQE7B6CwTHf5+cdRJDaC/eOkCZtgjQNFQL GJe7/iUSMJnNEuwsWd16R1Itr1Qa6oFcvUHlbwwD8Cfqnx3QO0K0Mb1+SdvShMielNoJ pipw== X-Gm-Message-State: AFqh2kqixeuQnG/5G4bqHCIvYI9udtCBhDcloqfqGg/HniobVkGW3OgL elE5aUXlFynhz5ihiadBlfbvyQ== X-Google-Smtp-Source: AMrXdXvCBIkAEZGDbN/ZqLtvndgjBWGXqt3p/tDjEf4UH4lqYIbGvE+PTCzH+rfOp05DrRSehw+yfw== X-Received: by 2002:a05:651c:2004:b0:27f:ff67:91cb with SMTP id s4-20020a05651c200400b0027fff6791cbmr6924851ljo.12.1673464811513; Wed, 11 Jan 2023 11:20:11 -0800 (PST) Received: from umbar.unikie.fi ([192.130.178.91]) by smtp.gmail.com with ESMTPSA id bj36-20020a2eaaa4000000b0027ff2fabcb5sm1807787ljb.104.2023.01.11.11.20.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Jan 2023 11:20:11 -0800 (PST) From: Dmitry Baryshkov To: Andy Gross , Bjorn Andersson , Konrad Dybcio , Stephen Boyd , Michael Turquette , Rob Herring , Krzysztof Kozlowski , Taniya Das Cc: linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH 06/13] clk: qcom: cpu-8996: simplify the cpu_clk_notifier_cb Date: Wed, 11 Jan 2023 22:19:57 +0300 Message-Id: <20230111192004.2509750-7-dmitry.baryshkov@linaro.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230111192004.2509750-1-dmitry.baryshkov@linaro.org> References: <20230111192004.2509750-1-dmitry.baryshkov@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org - Do not use the Alt PLL completely. Switch to smux when necessary to prevent overvolting - Restore the parent in case the rate change aborts for some reason - Do not duplicate resetting the parent in set_parent operation. Signed-off-by: Dmitry Baryshkov --- drivers/clk/qcom/clk-cpu-8996.c | 31 +++++++++++++++++++------------ 1 file changed, 19 insertions(+), 12 deletions(-) diff --git a/drivers/clk/qcom/clk-cpu-8996.c b/drivers/clk/qcom/clk-cpu-8996.c index 7e5246ca7e7f..ee7e18b37832 100644 --- a/drivers/clk/qcom/clk-cpu-8996.c +++ b/drivers/clk/qcom/clk-cpu-8996.c @@ -506,27 +506,34 @@ static int cpu_clk_notifier_cb(struct notifier_block *nb, unsigned long event, { struct clk_cpu_8996_pmux *cpuclk = to_clk_cpu_8996_pmux_nb(nb); struct clk_notifier_data *cnd = data; - int ret; switch (event) { case PRE_RATE_CHANGE: - ret = clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, ALT_INDEX); qcom_cpu_clk_msm8996_acd_init(base); + + /* + * Avoid overvolting. clk_core_set_rate_nolock() walks from top + * to bottom, so it will change the rate of the PLL before + * chaging the parent of PMUX. This can result in pmux getting + * clocked twice the expected rate. + * + * Manually switch to PLL/2 here. + */ + if (cnd->new_rate < DIV_2_THRESHOLD && + cnd->old_rate > DIV_2_THRESHOLD) + clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, SMUX_INDEX); + break; - case POST_RATE_CHANGE: - if (cnd->new_rate < DIV_2_THRESHOLD) - ret = clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, - SMUX_INDEX); - else - ret = clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, - ACD_INDEX); - break; + case ABORT_RATE_CHANGE: + /* Revert manual change */ + if (cnd->new_rate < DIV_2_THRESHOLD && + cnd->old_rate > DIV_2_THRESHOLD) + clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, ACD_INDEX); default: - ret = 0; break; } - return notifier_from_errno(ret); + return NOTIFY_OK; }; static int qcom_cpu_clk_msm8996_driver_probe(struct platform_device *pdev)