From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id AFC3817753 for ; Mon, 18 Mar 2024 01:13:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710724392; cv=none; b=XaHQN8m20sQ1+X23FQPpXxT5tVVCsSEbZG1jmZIDgp3fX2qnXlrns7La2kL+e5tDFrzssGclLM/JXhkY/z0yuYMS25M/KBPpqnKk4eg3HJOSV2BspdscnBRIqhduXio0lYdV9UVh21Q0UcvA1biDId9OL57YLmHUwTr6bKHkrBE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710724392; c=relaxed/simple; bh=m33hWOJXIw085kW48MyDjARBe58ZmVTMGPmErP2tLqo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=lqdNml883toQ2B1aXC2/+OrmaQ8y5N9piP5TeVWrLCn9TLnpN4TsFSvQZkBkn2KuLS4DBOgjHP8rOsCNn14tE3ja7MZeyrn8Jcp9daN8lplyPuFZ0dF4WU0pHz7VQ3JFrhah8rBUu2IBGH6ufIBkI/KBBOvR6Rsf+Xw1KrwEPDU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A07E512FC; Sun, 17 Mar 2024 18:13:44 -0700 (PDT) Received: from localhost.localdomain (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7B62A3F23F; Sun, 17 Mar 2024 18:13:07 -0700 (PDT) From: Andre Przywara To: Yangtao Li , Viresh Kumar , Nishanth Menon , Stephen Boyd , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , "Rafael J . Wysocki" Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-sunxi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Brandon Cheo Fusi , Martin Botka , Martin Botka Subject: [PATCH v2 5/8] cpufreq: sun50i: Add support for opp_supported_hw Date: Mon, 18 Mar 2024 01:12:25 +0000 Message-Id: <20240318011228.2626-6-andre.przywara@arm.com> X-Mailer: git-send-email 2.35.8 In-Reply-To: <20240318011228.2626-1-andre.przywara@arm.com> References: <20240318011228.2626-1-andre.przywara@arm.com> Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The opp_supported_hw DT property allows the DT to specify a mask of chip revisions that a certain OPP is eligible for. This allows for easy limiting of maximum frequencies, for instance. Add support for that in the sun50i-cpufreq-nvmem driver. We support both the existing opp-microvolt suffix properties as well as the opp-supported-hw property, the generic code figures out which is needed automatically. However if none of the DT OPP nodes contain an opp-supported-hw property, the core code will ignore all OPPs and the driver will fail probing. So check the DT's eligibility first before using that feature. Signed-off-by: Andre Przywara --- drivers/cpufreq/sun50i-cpufreq-nvmem.c | 62 ++++++++++++++++++++++---- 1 file changed, 54 insertions(+), 8 deletions(-) diff --git a/drivers/cpufreq/sun50i-cpufreq-nvmem.c b/drivers/cpufreq/sun50i-cpufreq-nvmem.c index 7b44f3b13e7d2..bd170611c7906 100644 --- a/drivers/cpufreq/sun50i-cpufreq-nvmem.c +++ b/drivers/cpufreq/sun50i-cpufreq-nvmem.c @@ -57,6 +57,41 @@ static const struct of_device_id cpu_opp_match_list[] = { {} }; +/** + * dt_has_supported_hw() - Check if any OPPs use opp-supported-hw + * + * If we ask the cpufreq framework to use the opp-supported-hw feature, it + * will ignore every OPP node without that DT property. If none of the OPPs + * have it, the driver will fail probing, due to the lack of OPPs. + * + * Returns true if we have at least one OPP with the opp-supported-hw property. + */ +static bool dt_has_supported_hw(void) +{ + bool has_opp_supported_hw = false; + struct device_node *np, *opp; + struct device *cpu_dev; + + cpu_dev = get_cpu_device(0); + if (!cpu_dev) + return -ENODEV; + + np = dev_pm_opp_of_get_opp_desc_node(cpu_dev); + if (!np) + return -ENOENT; + + for_each_child_of_node(np, opp) { + if (of_find_property(opp, "opp-supported-hw", NULL)) { + has_opp_supported_hw = true; + break; + } + } + + of_node_put(np); + + return has_opp_supported_hw; +} + /** * sun50i_cpufreq_get_efuse() - Determine speed grade from efuse value * @@ -110,7 +145,8 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev) { int *opp_tokens; char name[MAX_NAME_LEN]; - unsigned int cpu; + unsigned int cpu, supported_hw; + struct dev_pm_opp_config config = {}; int speed; int ret; @@ -125,7 +161,18 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev) return speed; } + /* + * We need at least one OPP with the "opp-supported-hw" property, + * or else the upper layers will ignore every OPP and will bail out. + */ + if (dt_has_supported_hw()) { + supported_hw = 1U << speed; + config.supported_hw = &supported_hw; + config.supported_hw_count = 1; + } + snprintf(name, MAX_NAME_LEN, "speed%d", speed); + config.prop_name = name; for_each_possible_cpu(cpu) { struct device *cpu_dev = get_cpu_device(cpu); @@ -135,12 +182,11 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev) goto free_opp; } - opp_tokens[cpu] = dev_pm_opp_set_prop_name(cpu_dev, name); - if (opp_tokens[cpu] < 0) { - ret = opp_tokens[cpu]; - pr_err("Failed to set prop name\n"); + ret = dev_pm_opp_set_config(cpu_dev, &config); + if (ret < 0) goto free_opp; - } + + opp_tokens[cpu] = ret; } cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1, @@ -155,7 +201,7 @@ static int sun50i_cpufreq_nvmem_probe(struct platform_device *pdev) free_opp: for_each_possible_cpu(cpu) - dev_pm_opp_put_prop_name(opp_tokens[cpu]); + dev_pm_opp_clear_config(opp_tokens[cpu]); kfree(opp_tokens); return ret; @@ -169,7 +215,7 @@ static void sun50i_cpufreq_nvmem_remove(struct platform_device *pdev) platform_device_unregister(cpufreq_dt_pdev); for_each_possible_cpu(cpu) - dev_pm_opp_put_prop_name(opp_tokens[cpu]); + dev_pm_opp_clear_config(opp_tokens[cpu]); kfree(opp_tokens); } -- 2.35.8