[mirror_ubuntu-bionic-kernel.git] / arch / arm / plat-omap / cpu-omap.c

/*
 *  linux/arch/arm/plat-omap/cpu-omap.c
 *
 *  CPU frequency scaling for OMAP
 *
 *  Copyright (C) 2005 Nokia Corporation
 *  Written by Tony Lindgren <tony@atomide.com>
 *
 *  Based on cpu-sa1110.c, Copyright (C) 2001 Russell King
 *
 * 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.
 */
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/cpufreq.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/clk.h>

#include <mach/hardware.h>
#include <asm/io.h>
#include <asm/system.h>

#define VERY_HI_RATE	900000000

#ifdef CONFIG_ARCH_OMAP1
#define MPU_CLK		"mpu"
#else
#define MPU_CLK		"virt_prcm_set"
#endif

static struct clk *mpu_clk;

/* TODO: Add support for SDRAM timing changes */

int omap_verify_speed(struct cpufreq_policy *policy)
{
	if (policy->cpu)
		return -EINVAL;

	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
				     policy->cpuinfo.max_freq);

	policy->min = clk_round_rate(mpu_clk, policy->min * 1000) / 1000;
	policy->max = clk_round_rate(mpu_clk, policy->max * 1000) / 1000;
	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
				     policy->cpuinfo.max_freq);
	return 0;
}

unsigned int omap_getspeed(unsigned int cpu)
{
	unsigned long rate;

	if (cpu)
		return 0;

	rate = clk_get_rate(mpu_clk) / 1000;
	return rate;
}

static int omap_target(struct cpufreq_policy *policy,
		       unsigned int target_freq,
		       unsigned int relation)
{
	struct cpufreq_freqs freqs;
	int ret = 0;

	freqs.old = omap_getspeed(0);
	freqs.new = clk_round_rate(mpu_clk, target_freq * 1000) / 1000;
	freqs.cpu = 0;

	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
	ret = clk_set_rate(mpu_clk, target_freq * 1000);
	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);

	return ret;
}

static int __init omap_cpu_init(struct cpufreq_policy *policy)
{
	mpu_clk = clk_get(NULL, MPU_CLK);
	if (IS_ERR(mpu_clk))
		return PTR_ERR(mpu_clk);

	if (policy->cpu != 0)
		return -EINVAL;
	policy->cur = policy->min = policy->max = omap_getspeed(0);
	policy->cpuinfo.min_freq = clk_round_rate(mpu_clk, 0) / 1000;
	policy->cpuinfo.max_freq = clk_round_rate(mpu_clk, VERY_HI_RATE) / 1000;
	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;

	return 0;
}

static int omap_cpu_exit(struct cpufreq_policy *policy)
{
	clk_put(mpu_clk);
	return 0;
}

static struct cpufreq_driver omap_driver = {
	.flags		= CPUFREQ_STICKY,
	.verify		= omap_verify_speed,
	.target		= omap_target,
	.get		= omap_getspeed,
	.init		= omap_cpu_init,
	.exit		= omap_cpu_exit,
	.name		= "omap",
};

static int __init omap_cpufreq_init(void)
{
	return cpufreq_register_driver(&omap_driver);
}

arch_initcall(omap_cpufreq_init);
Commit	Line	Data
ec6bced6 TL	1	/*
	2	* linux/arch/arm/plat-omap/cpu-omap.c
	3	*
	4	* CPU frequency scaling for OMAP
	5	*
	6	* Copyright (C) 2005 Nokia Corporation
	7	* Written by Tony Lindgren <tony@atomide.com>
	8	*
	9	* Based on cpu-sa1110.c, Copyright (C) 2001 Russell King
	10	*
	11	* This program is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License version 2 as
	13	* published by the Free Software Foundation.
	14	*/
	15	#include <linux/types.h>
	16	#include <linux/kernel.h>
	17	#include <linux/sched.h>
	18	#include <linux/cpufreq.h>
	19	#include <linux/delay.h>
	20	#include <linux/init.h>
	21	#include <linux/err.h>
f8ce2547	22	#include <linux/clk.h>
ec6bced6	23
a09e64fb	24	#include <mach/hardware.h>
ec6bced6 TL	25	#include <asm/io.h>
	26	#include <asm/system.h>
	27
a7ca9d2b TL	28	#define VERY_HI_RATE 900000000
	29
	30	#ifdef CONFIG_ARCH_OMAP1
	31	#define MPU_CLK "mpu"
	32	#else
	33	#define MPU_CLK "virt_prcm_set"
	34	#endif
	35
b8488fbe HD	36	static struct clk *mpu_clk;
b8488fbe HD	37
ec6bced6 TL	38	/* TODO: Add support for SDRAM timing changes */
	39
	40	int omap_verify_speed(struct cpufreq_policy *policy)
	41	{
ec6bced6 TL	42	if (policy->cpu)
	43	return -EINVAL;
	44
	45	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
	46	policy->cpuinfo.max_freq);
b8488fbe	47
ec6bced6 TL	48	policy->min = clk_round_rate(mpu_clk, policy->min * 1000) / 1000;
	49	policy->max = clk_round_rate(mpu_clk, policy->max * 1000) / 1000;
	50	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
	51	policy->cpuinfo.max_freq);
ec6bced6 TL	52	return 0;
	53	}
	54
	55	unsigned int omap_getspeed(unsigned int cpu)
	56	{
ec6bced6 TL	57	unsigned long rate;
	58
	59	if (cpu)
	60	return 0;
	61
ec6bced6	62	rate = clk_get_rate(mpu_clk) / 1000;
ec6bced6 TL	63	return rate;
	64	}
	65
	66	static int omap_target(struct cpufreq_policy *policy,
	67	unsigned int target_freq,
	68	unsigned int relation)
	69	{
ec6bced6 TL	70	struct cpufreq_freqs freqs;
	71	int ret = 0;
	72
ec6bced6 TL	73	freqs.old = omap_getspeed(0);
	74	freqs.new = clk_round_rate(mpu_clk, target_freq * 1000) / 1000;
	75	freqs.cpu = 0;
	76
	77	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
	78	ret = clk_set_rate(mpu_clk, target_freq * 1000);
	79	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
ec6bced6 TL	80
	81	return ret;
	82	}
	83
	84	static int __init omap_cpu_init(struct cpufreq_policy *policy)
	85	{
a7ca9d2b	86	mpu_clk = clk_get(NULL, MPU_CLK);
ec6bced6 TL	87	if (IS_ERR(mpu_clk))
	88	return PTR_ERR(mpu_clk);
	89
	90	if (policy->cpu != 0)
	91	return -EINVAL;
	92	policy->cur = policy->min = policy->max = omap_getspeed(0);
ec6bced6	93	policy->cpuinfo.min_freq = clk_round_rate(mpu_clk, 0) / 1000;
a7ca9d2b	94	policy->cpuinfo.max_freq = clk_round_rate(mpu_clk, VERY_HI_RATE) / 1000;
ec6bced6	95	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
ec6bced6 TL	96
	97	return 0;
	98	}
	99
b8488fbe HD	100	static int omap_cpu_exit(struct cpufreq_policy *policy)
	101	{
	102	clk_put(mpu_clk);
	103	return 0;
	104	}
	105
ec6bced6 TL	106	static struct cpufreq_driver omap_driver = {
	107	.flags = CPUFREQ_STICKY,
	108	.verify = omap_verify_speed,
	109	.target = omap_target,
	110	.get = omap_getspeed,
	111	.init = omap_cpu_init,
b8488fbe	112	.exit = omap_cpu_exit,
ec6bced6 TL	113	.name = "omap",
	114	};
	115
	116	static int __init omap_cpufreq_init(void)
	117	{
	118	return cpufreq_register_driver(&omap_driver);
	119	}
	120
	121	arch_initcall(omap_cpufreq_init);