From patchwork Fri Jul 31 17:43:08 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 6915231 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 7D7289F358 for ; Fri, 31 Jul 2015 17:48:42 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EF4C2203A0 for ; Fri, 31 Jul 2015 17:48:40 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5ED1A203DC for ; Fri, 31 Jul 2015 17:48:36 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZLEOu-00043D-4S; Fri, 31 Jul 2015 17:47:20 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZLELj-0000Kc-Dg for linux-arm-kernel@lists.infradead.org; Fri, 31 Jul 2015 17:44:08 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E15565E2; Fri, 31 Jul 2015 10:43:41 -0700 (PDT) Received: from e103737-lin.cambridge.arm.com (e103737-lin.cambridge.arm.com [10.1.207.150]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DAB0C3F483; Fri, 31 Jul 2015 10:43:32 -0700 (PDT) From: Sudeep Holla To: arm@kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Olof Johansson , Kevin Hilman Subject: [PATCH v6 5/8] cpufreq: arm_big_little: add SCPI interface driver Date: Fri, 31 Jul 2015 18:43:08 +0100 Message-Id: <1438364591-1144-6-git-send-email-sudeep.holla@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1438364591-1144-1-git-send-email-sudeep.holla@arm.com> References: <1438364591-1144-1-git-send-email-sudeep.holla@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150731_104403_620518_8C9C09D9 X-CRM114-Status: GOOD ( 19.93 ) X-Spam-Score: -8.3 (--------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Jon Medhurst \(Tixy\)" , "Rafael J. Wysocki" , Lorenzo Pieralisi , Arnd Bergmann , linux-pm@vger.kernel.org, Viresh Kumar , Punit Agrawal , Liviu Dudau , Sudeep Holla MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On some ARM based systems, a separate Cortex-M based System Control Processor(SCP) provides the overall power, clock, reset and system control including CPU DVFS. SCPI Message Protocol is used to communicate with the SCPI. This patch adds a interface driver for adding OPPs and registering the arm_big_little cpufreq driver for such systems. Signed-off-by: Sudeep Holla Acked-by: Viresh Kumar Cc: Viresh Kumar Cc: "Rafael J. Wysocki" Cc: linux-pm@vger.kernel.org --- MAINTAINERS | 1 + drivers/cpufreq/Kconfig.arm | 9 +++ drivers/cpufreq/Makefile | 1 + drivers/cpufreq/scpi-cpufreq.c | 124 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 135 insertions(+) create mode 100644 drivers/cpufreq/scpi-cpufreq.c diff --git a/MAINTAINERS b/MAINTAINERS index 690122bb4426..d4b912664a93 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8966,6 +8966,7 @@ L: linux-arm-kernel@lists.infradead.org S: Maintained F: Documentation/devicetree/bindings/arm/arm,scpi.txt F: drivers/clk/clk-scpi.c +F: drivers/cpufreq/scpi-cpufreq.c F: drivers/firmware/arm_scpi.c F: include/linux/scpi_protocol.h diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index cc8a71c267b8..c46b495169af 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -24,6 +24,15 @@ config ARM_VEXPRESS_SPC_CPUFREQ This add the CPUfreq driver support for Versatile Express big.LITTLE platforms using SPC for power management. +config ARM_SCPI_CPUFREQ + tristate "SCPI based CPUfreq driver" + depends on ARM_BIG_LITTLE_CPUFREQ && ARM_SCPI_PROTOCOL + help + This adds the CPUfreq driver support for ARM big.LITTLE platforms + using SCPI protocol for CPU power management. + + This driver uses SCPI Message Protocol driver to interact with the + firmware providing the CPU DVFS functionality. config ARM_EXYNOS_CPUFREQ tristate "SAMSUNG EXYNOS CPUfreq Driver" diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 2169bf792db7..7e07f5535c3a 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -78,6 +78,7 @@ obj-$(CONFIG_ARM_SA1110_CPUFREQ) += sa1110-cpufreq.o obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o obj-$(CONFIG_ARM_TEGRA_CPUFREQ) += tegra-cpufreq.o obj-$(CONFIG_ARM_VEXPRESS_SPC_CPUFREQ) += vexpress-spc-cpufreq.o +obj-$(CONFIG_ARM_SCPI_CPUFREQ) += scpi-cpufreq.o ################################################################################## # PowerPC platform drivers diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c new file mode 100644 index 000000000000..2c3b16fd3a01 --- /dev/null +++ b/drivers/cpufreq/scpi-cpufreq.c @@ -0,0 +1,124 @@ +/* + * System Control and Power Interface (SCPI) based CPUFreq Interface driver + * + * It provides necessary ops to arm_big_little cpufreq driver. + * + * Copyright (C) 2015 ARM Ltd. + * Sudeep Holla + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include + +#include "arm_big_little.h" + +static struct scpi_ops *scpi_ops; + +static struct scpi_dvfs_info *scpi_get_dvfs_info(struct device *cpu_dev) +{ + u8 domain = topology_physical_package_id(cpu_dev->id); + + if (domain < 0) + return ERR_PTR(-EINVAL); + return scpi_ops->dvfs_get_info(domain); +} + +static int scpi_opp_table_ops(struct device *cpu_dev, bool remove) +{ + int idx, ret = 0; + struct scpi_opp *opp; + struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev); + + if (IS_ERR(info)) + return PTR_ERR(info); + + if (!info->opps) + return -EIO; + + for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) { + if (remove) + dev_pm_opp_remove(cpu_dev, opp->freq); + else + ret = dev_pm_opp_add(cpu_dev, opp->freq, + opp->m_volt * 1000); + if (ret) { + dev_warn(cpu_dev, "failed to add opp %uHz %umV\n", + opp->freq, opp->m_volt); + while (idx-- > 0) + dev_pm_opp_remove(cpu_dev, (--opp)->freq); + return ret; + } + } + return ret; +} + +static int scpi_get_transition_latency(struct device *cpu_dev) +{ + struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev); + + if (IS_ERR(info)) + return PTR_ERR(info); + return info->latency; +} + +static int scpi_init_opp_table(struct device *cpu_dev) +{ + return scpi_opp_table_ops(cpu_dev, false); +} + +static void scpi_free_opp_table(struct device *cpu_dev) +{ + scpi_opp_table_ops(cpu_dev, true); +} + +static struct cpufreq_arm_bL_ops scpi_cpufreq_ops = { + .name = "scpi", + .get_transition_latency = scpi_get_transition_latency, + .init_opp_table = scpi_init_opp_table, + .free_opp_table = scpi_free_opp_table, +}; + +static int scpi_cpufreq_probe(struct platform_device *pdev) +{ + scpi_ops = get_scpi_ops(); + if (!scpi_ops) + return -EIO; + + return bL_cpufreq_register(&scpi_cpufreq_ops); +} + +static int scpi_cpufreq_remove(struct platform_device *pdev) +{ + bL_cpufreq_unregister(&scpi_cpufreq_ops); + scpi_ops = NULL; + return 0; +} + +static struct platform_driver scpi_cpufreq_platdrv = { + .driver = { + .name = "scpi-cpufreq", + .owner = THIS_MODULE, + }, + .probe = scpi_cpufreq_probe, + .remove = scpi_cpufreq_remove, +}; +module_platform_driver(scpi_cpufreq_platdrv); + +MODULE_AUTHOR("Sudeep Holla "); +MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver"); +MODULE_LICENSE("GPL v2");