linux/drivers/cpufreq/unicore2-cpufreq.c
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  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 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 #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00

77 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* clock scaling for the UniCore-II
*
* Code specific to PKUnity SoC and UniCore ISA
*
* Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
* Copyright (C) 2001-2010 Guan Xuetao
*/
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <mach/hardware.h>
static struct cpufreq_driver ucv2_driver;
/* make sure that only the "userspace" governor is run
* -- anything else wouldn't make sense on this platform, anyway.
*/
static int ucv2_verify_speed(struct cpufreq_policy *policy)
{
if (policy->cpu)
return -EINVAL;
cpufreq_verify_within_cpu_limits(policy);
return 0;
}
static int ucv2_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct cpufreq_freqs freqs;
int ret;
freqs.old = policy->cur;
freqs.new = target_freq;
cpufreq_freq_transition_begin(policy, &freqs);
ret = clk_set_rate(policy->clk, target_freq * 1000);
cpufreq_freq_transition_end(policy, &freqs, ret);
return ret;
}
static int __init ucv2_cpu_init(struct cpufreq_policy *policy)
{
if (policy->cpu != 0)
return -EINVAL;
policy->min = policy->cpuinfo.min_freq = 250000;
policy->max = policy->cpuinfo.max_freq = 1000000;
policy->clk = clk_get(NULL, "MAIN_CLK");
return PTR_ERR_OR_ZERO(policy->clk);
}
static struct cpufreq_driver ucv2_driver = {
.flags = CPUFREQ_STICKY | CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING,
.verify = ucv2_verify_speed,
.target = ucv2_target,
.get = cpufreq_generic_get,
.init = ucv2_cpu_init,
.name = "UniCore-II",
};
static int __init ucv2_cpufreq_init(void)
{
return cpufreq_register_driver(&ucv2_driver);
}
arch_initcall(ucv2_cpufreq_init);