a09e64fbc0
This just leaves include/asm-arm/plat-* to deal with. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
121 lines
2.8 KiB
C
121 lines
2.8 KiB
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);
|