[mirror_ubuntu-jammy-kernel.git] / drivers / cpufreq / unicore2-cpufreq.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_data *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);
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
64909882	2	/*
73cc9c8c	3	* clock scaling for the UniCore-II
64909882 G	4	*
	5	* Code specific to PKUnity SoC and UniCore ISA
	6	*
	7	* Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
	8	* Copyright (C) 2001-2010 Guan Xuetao
64909882 G	9	*/
64909882 G	10
652ed95d	11	#include <linux/err.h>
64909882 G	12	#include <linux/kernel.h>
	13	#include <linux/types.h>
	14	#include <linux/init.h>
	15	#include <linux/clk.h>
	16	#include <linux/cpufreq.h>
	17
	18	#include <mach/hardware.h>
	19
	20	static struct cpufreq_driver ucv2_driver;
	21
	22	/* make sure that only the "userspace" governor is run
	23	* -- anything else wouldn't make sense on this platform, anyway.
	24	*/
1e4f63ae	25	static int ucv2_verify_speed(struct cpufreq_policy_data *policy)
64909882 G	26	{
	27	if (policy->cpu)
	28	return -EINVAL;
	29
be49e346	30	cpufreq_verify_within_cpu_limits(policy);
64909882 G	31	return 0;
	32	}
	33
64909882 G	34	static int ucv2_target(struct cpufreq_policy *policy,
	35	unsigned int target_freq,
	36	unsigned int relation)
	37	{
64909882	38	struct cpufreq_freqs freqs;
ab1b1c4e	39	int ret;
64909882	40
ab1b1c4e VK	41	freqs.old = policy->cur;
ab1b1c4e VK	42	freqs.new = target_freq;
64909882	43
8fec051e	44	cpufreq_freq_transition_begin(policy, &freqs);
b4ddad95	45	ret = clk_set_rate(policy->clk, target_freq * 1000);
8fec051e	46	cpufreq_freq_transition_end(policy, &freqs, ret);
64909882	47
ab1b1c4e	48	return ret;
64909882 G	49	}
	50
	51	static int __init ucv2_cpu_init(struct cpufreq_policy *policy)
	52	{
	53	if (policy->cpu != 0)
	54	return -EINVAL;
652ed95d	55
64909882 G	56	policy->min = policy->cpuinfo.min_freq = 250000;
64909882 G	57	policy->max = policy->cpuinfo.max_freq = 1000000;
652ed95d	58	policy->clk = clk_get(NULL, "MAIN_CLK");
8ab4e2b3	59	return PTR_ERR_OR_ZERO(policy->clk);
64909882 G	60	}
	61
	62	static struct cpufreq_driver ucv2_driver = {
fe829ed8	63	.flags = CPUFREQ_STICKY \| CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING,
64909882 G	64	.verify = ucv2_verify_speed,
64909882 G	65	.target = ucv2_target,
652ed95d	66	.get = cpufreq_generic_get,
64909882 G	67	.init = ucv2_cpu_init,
	68	.name = "UniCore-II",
	69	};
	70
	71	static int __init ucv2_cpufreq_init(void)
	72	{
	73	return cpufreq_register_driver(&ucv2_driver);
	74	}
	75
	76	arch_initcall(ucv2_cpufreq_init);