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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 264FDC04AAF for ; Mon, 20 May 2019 12:41:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0658F20645 for ; Mon, 20 May 2019 12:41:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389850AbfETMbN (ORCPT ); Mon, 20 May 2019 08:31:13 -0400 Received: from mout.kundenserver.de ([212.227.126.131]:57939 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390275AbfETMbM (ORCPT ); Mon, 20 May 2019 08:31:12 -0400 Received: from [192.168.178.167] ([109.104.33.162]) by mrelayeu.kundenserver.de (mreue010 [212.227.15.167]) with ESMTPSA (Nemesis) id 1MVMuN-1h3E3m0KCl-00SRFw; Mon, 20 May 2019 14:30:53 +0200 Subject: Re: [RFC v2 5/5] cpufreq: add driver for Raspbery Pi To: Nicolas Saenz Julienne , "Rafael J. Wysocki" , Viresh Kumar Cc: mbrugger@suse.de, sboyd@kernel.org, eric@anholt.net, f.fainelli@gmail.com, bcm-kernel-feedback-list@broadcom.com, ptesarik@suse.com, linux-rpi-kernel@lists.infradead.org, ssuloev@orpaltech.com, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, mturquette@baylibre.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org References: <20190520104708.11980-1-nsaenzjulienne@suse.de> <20190520104708.11980-6-nsaenzjulienne@suse.de> From: Stefan Wahren Message-ID: Date: Mon, 20 May 2019 14:30:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190520104708.11980-6-nsaenzjulienne@suse.de> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Provags-ID: V03:K1:8EPy0TEJACtLRM++yjvBbmbVCw2iG8lr+b2JXdcGP7gvIcA4EEF 56n5p7w6xmP6ibp3AyK5HtXHzKAv9Bq8BsS2bg2iccrymCgCiJAjQ4TkTr7vGZecgfh5pVx hFT+McXrzs0zuDaAwa4gcZC2IHmf/QjzYzdSV0nE1ZKWOFCxpfSuORzsoNbnkSWwGgwXnAk 9AUB7HqT/Rv21BjVmbEKA== X-UI-Out-Filterresults: notjunk:1;V03:K0:oYIxwR3Gy8w=:WYzhHcJaMcyZ+BIqULb+5H ci6BYAOtjHdDZOMuqgG/ejVx61x9vJMvtKwcYw3PhVtnxd8ZA9wBsdxOkUlpPK27+z915WKKa 3eeBGNa82w2KtxWzBhfLqeP+xdcmQjau0I+c2cWaqVL+wBntXBwbzM8rfvLfQdXv3FUYsH9j8 eYr26BuKzVpPA/pYl9KbZVC47cfubAtziM5tnxwSwPRlWrgHP39RrxVyuB2ecxHH49Ge/Rt6K dJA7T/91PuYfMtxRzz+5gZ3aZf6nnpT9NhQbbtCAhtg6YRGx6SL/H36Tdt2emsnD1GlhXlcij OQFyYDLP6lJHTb8iStv6FAzGDTHdNxKETDeTsG9Pmdih9bc29n8mhFYvsIsA/9YsmsffEN4jT SHdd0HPsTrTW4tCcgfbVgTMq+Phfkl+SiAIA0kmNOthusgaDyeyKwvq67+tJpzaxyAmg6ZQIV YfkNYqPQ0hFY6DI1BE54Hpu27Mlh+xltQQdXzzB5yjljibFYwuJNYV3OcR/hV34EOdrlrV6rF wPliF0seMgDjg0NVDBwLfDMmSmPCNMzFh+heKtdH0eeVbq3Riw5LzNbYtmrP0WdeP3/yecUtr 1p5nwjAdlxXQaFI/0Q/TYr8wCFrCHHze2e7j1Afeiwmbk9Kg6TkF/VuJuMlAB+/yr94rbDOGe 0mgpn/IN1+gnN3rGeWR/P/lM5tdgqnXu8jNWrK2ta1i5fmzql4gRS8odH5lc/3GQ6fpsfuQGc CCcxFE/fS+qf0Ojx1BpdZ6fT2n7XQT/vgR/Z9EJx0JWHtmNpQ7Ln9jK/xtg= Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 20.05.19 12:47, Nicolas Saenz Julienne wrote: > Raspberry Pi's firmware offers and interface though which update it's > performance requirements. It allows us to request for specific runtime > frequencies, which the firmware might or might not respect, depending on > the firmware configuration and thermals. > > As the maximum and minimum frequencies are configurable in the firmware > there is no way to know in advance their values. So the Raspberry Pi > cpufreq driver queries them, builds an opp frequency table to then > launch cpufreq-dt. > > Signed-off-by: Nicolas Saenz Julienne > --- > drivers/cpufreq/Kconfig.arm | 8 +++ > drivers/cpufreq/Makefile | 1 + > drivers/cpufreq/raspberrypi-cpufreq.c | 83 +++++++++++++++++++++++++++ > 3 files changed, 92 insertions(+) > create mode 100644 drivers/cpufreq/raspberrypi-cpufreq.c > > diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm > index 179a1d302f48..f6eba7ae50d0 100644 > --- a/drivers/cpufreq/Kconfig.arm > +++ b/drivers/cpufreq/Kconfig.arm > @@ -308,3 +308,11 @@ config ARM_PXA2xx_CPUFREQ > This add the CPUFreq driver support for Intel PXA2xx SOCs. > > If in doubt, say N. > + > +config ARM_RASPBERRYPI_CPUFREQ > + tristate "Raspberry Pi cpufreq support" > + depends on RASPBERRYPI_FIRMWARE || COMPILE_TEST The driver doesn't really require the firmware driver to compile, how about: select RASPBERRYPI_FIRMWARE > + help > + This adds the CPUFreq driver for Raspberry Pi > + > + If in doubt, say N. > diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile > index 689b26c6f949..02678e9b2ff5 100644 > --- a/drivers/cpufreq/Makefile > +++ b/drivers/cpufreq/Makefile > @@ -84,6 +84,7 @@ obj-$(CONFIG_ARM_TEGRA124_CPUFREQ) += tegra124-cpufreq.o > obj-$(CONFIG_ARM_TEGRA186_CPUFREQ) += tegra186-cpufreq.o > obj-$(CONFIG_ARM_TI_CPUFREQ) += ti-cpufreq.o > obj-$(CONFIG_ARM_VEXPRESS_SPC_CPUFREQ) += vexpress-spc-cpufreq.o > +obj-$(CONFIG_ARM_RASPBERRYPI_CPUFREQ) += raspberrypi-cpufreq.o > > > ################################################################################## > diff --git a/drivers/cpufreq/raspberrypi-cpufreq.c b/drivers/cpufreq/raspberrypi-cpufreq.c > new file mode 100644 > index 000000000000..a85988867d56 > --- /dev/null > +++ b/drivers/cpufreq/raspberrypi-cpufreq.c > @@ -0,0 +1,83 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Raspberry Pi cpufreq driver > + * > + * Copyright (C) 2019, Nicolas Saenz Julienne > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +static const struct of_device_id machines[] __initconst = { > + { .compatible = "raspberrypi,3-model-b-plus" }, > + { .compatible = "raspberrypi,3-model-b" }, > + { /* sentinel */ } > +}; > + > +static int __init raspberrypi_cpufreq_driver_init(void) > +{ > + struct platform_device *pdev; > + struct device *cpu_dev; > + struct clk *clk; > + long min, max; > + long rate; > + int ret; > + > + if (!of_match_node(machines, of_root)) > + return -ENODEV; > + > + cpu_dev = get_cpu_device(0); > + if (!cpu_dev) { > + pr_err("Cannot get CPU for cpufreq driver\n"); > + return -ENODEV; > + } > + > + clk = clk_get(cpu_dev, 0); I suggest use the expected clock ID.