linux-imx

/*

 * Cpufreq driver for the loongson-2 processors

 *

 * The 2E revision of loongson processor not support this feature.

 *

 * Copyright (C) 2006 - 2008 Lemote Inc. & Institute of Computing Technology

 * Author: Yanhua, yanh@lemote.com

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/cpufreq.h>

#include <linux/module.h>

#include <linux/err.h>

#include <linux/sched.h>    /* set_cpus_allowed() */

#include <linux/delay.h>

#include <linux/platform_device.h>

​

#include <asm/clock.h>

#include <asm/idle.h>

​

#include <asm/mach-loongson64/loongson.h>

​

static uint nowait;

​

static void (*saved_cpu_wait) (void);

​

static int loongson2_cpu_freq_notifier(struct notifier_block *nb,

                    unsigned long val, void *data);

​

static struct notifier_block loongson2_cpufreq_notifier_block = {

    .notifier_call = loongson2_cpu_freq_notifier

};

​

static int loongson2_cpu_freq_notifier(struct notifier_block *nb,

                    unsigned long val, void *data)

{

    if (val == CPUFREQ_POSTCHANGE)

        current_cpu_data.udelay_val = loops_per_jiffy;

​

    return 0;

}

​

/*

 * Here we notify other drivers of the proposed change and the final change.

 */

static int loongson2_cpufreq_target(struct cpufreq_policy *policy,

                     unsigned int index)

{

    unsigned int freq;

​

    freq =

        ((cpu_clock_freq / 1000) *

         loongson2_clockmod_table[index].driver_data) / 8;

​

    /* setting the cpu frequency */

    clk_set_rate(policy->clk, freq * 1000);

​

    return 0;