mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-25 02:30:52 +07:00
47ac9aa165
The TC2(i.e. CA15_A7) Versatile Express has external Cortex M3 based power controller which is responsible for CPU DVFS and SPC provides the interface for the same. This patch adds a tiny interface driver to check if OPPs are initialised by SPC platform code and register the arm_big_little cpufreq driver. Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
71 lines
1.9 KiB
C
71 lines
1.9 KiB
C
/*
|
|
* Versatile Express SPC CPUFreq Interface driver
|
|
*
|
|
* It provides necessary ops to arm_big_little cpufreq driver.
|
|
*
|
|
* Copyright (C) 2013 ARM Ltd.
|
|
* Sudeep KarkadaNagesha <sudeep.karkadanagesha@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/types.h>
|
|
|
|
#include "arm_big_little.h"
|
|
|
|
static int ve_spc_init_opp_table(struct device *cpu_dev)
|
|
{
|
|
/*
|
|
* platform specific SPC code must initialise the opp table
|
|
* so just check if the OPP count is non-zero
|
|
*/
|
|
return dev_pm_opp_get_opp_count(cpu_dev) <= 0;
|
|
}
|
|
|
|
static int ve_spc_get_transition_latency(struct device *cpu_dev)
|
|
{
|
|
return 1000000; /* 1 ms */
|
|
}
|
|
|
|
static struct cpufreq_arm_bL_ops ve_spc_cpufreq_ops = {
|
|
.name = "vexpress-spc",
|
|
.get_transition_latency = ve_spc_get_transition_latency,
|
|
.init_opp_table = ve_spc_init_opp_table,
|
|
};
|
|
|
|
static int ve_spc_cpufreq_probe(struct platform_device *pdev)
|
|
{
|
|
return bL_cpufreq_register(&ve_spc_cpufreq_ops);
|
|
}
|
|
|
|
static int ve_spc_cpufreq_remove(struct platform_device *pdev)
|
|
{
|
|
bL_cpufreq_unregister(&ve_spc_cpufreq_ops);
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver ve_spc_cpufreq_platdrv = {
|
|
.driver = {
|
|
.name = "vexpress-spc-cpufreq",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = ve_spc_cpufreq_probe,
|
|
.remove = ve_spc_cpufreq_remove,
|
|
};
|
|
module_platform_driver(ve_spc_cpufreq_platdrv);
|
|
|
|
MODULE_LICENSE("GPL");
|