diff options
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/Kconfig.arm | 10 | ||||
| -rw-r--r-- | drivers/cpufreq/Makefile | 1 | ||||
| -rw-r--r-- | drivers/cpufreq/scpi-cpufreq.c | 124 |
3 files changed, 135 insertions, 0 deletions
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index 642fd49793b0..1582c1c016b0 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -199,6 +199,16 @@ config ARM_SA1100_CPUFREQ config ARM_SA1110_CPUFREQ bool +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_SPEAR_CPUFREQ bool "SPEAr CPUFreq support" depends on PLAT_SPEAR diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index d11309c487d0..c0af1a1281c8 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -71,6 +71,7 @@ obj-$(CONFIG_ARM_S3C64XX_CPUFREQ) += s3c64xx-cpufreq.o obj-$(CONFIG_ARM_S5PV210_CPUFREQ) += s5pv210-cpufreq.o obj-$(CONFIG_ARM_SA1100_CPUFREQ) += sa1100-cpufreq.o obj-$(CONFIG_ARM_SA1110_CPUFREQ) += sa1110-cpufreq.o +obj-$(CONFIG_ARM_SCPI_CPUFREQ) += scpi-cpufreq.o obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o obj-$(CONFIG_ARM_TEGRA20_CPUFREQ) += tegra20-cpufreq.o obj-$(CONFIG_ARM_TEGRA124_CPUFREQ) += tegra124-cpufreq.o 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 <sudeep.holla@arm.com> + * + * 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 <linux/cpufreq.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_opp.h> +#include <linux/scpi_protocol.h> +#include <linux/types.h> + +#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 <sudeep.holla@arm.com>"); +MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver"); +MODULE_LICENSE("GPL v2"); |