File: [local] / prex-old / dev / power / cpufreq.c (download)
Revision 1.1.1.1 (vendor branch), Tue Jun 3 09:38:42 2008 UTC (16 years, 3 months ago) by nbrk
Branch: MAIN, KOHSUKE
CVS Tags: PREX_0_7_BASE, HEAD Branch point for: PREX_0_8_BASE
Changes since 1.1: +0 -0 lines
Yeah, this is an initial import of Prex, portable real-time microkernel
operating system. I wanna hack it for non-profit but fun, so let it in.
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/*-
* Copyright (c) 2007, Kohsuke Ohtani
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* cpufreq.c - CPU frequency control
*/
#include <sys/ioctl.h>
#include <driver.h>
#include <pm.h>
#include "dvs.h"
/* #define DEBUG_CPUFREQ 1 */
#ifdef DEBUG_CPUFREQ
#define cf_printf(fmt, args...) printk("cpufreq: " fmt, ## args)
#else
#define cf_printf(fmt...) do {} while (0)
#endif
static int cpufreq_open(device_t dev, int mode);
static int cpufreq_ioctl(device_t dev, int cmd, u_long arg);
static int cpufreq_close(device_t dev);
static int cpufreq_init(void);
/*
* Driver structure
*/
struct driver cpufreq_drv = {
/* name */ "CPU Frequency Control",
/* order */ 3, /* Must larger than pm driver */
/* init */ cpufreq_init,
};
static struct devio cpufreq_io = {
/* open */ cpufreq_open,
/* close */ cpufreq_close,
/* read */ NULL,
/* write */ NULL,
/* ioctl */ cpufreq_ioctl,
/* event */ NULL,
};
static device_t cpufreq_dev; /* Device object */
/*
* Frequecy control policy
*/
static int cpufreq_policy;
static int
cpufreq_open(device_t dev, int mode)
{
return 0;
}
static int
cpufreq_close(device_t dev)
{
return 0;
}
static int
cpufreq_ioctl(device_t dev, int cmd, u_long arg)
{
return 0;
}
void
cpufreq_setpolicy(int policy)
{
switch (cpufreq_policy) {
case CPUFREQ_ONDEMAND:
if (policy == PM_POWERSAVE)
dvs_enable();
else
dvs_disable();
break;
case CPUFREQ_MAXSPEED:
break;
case CPUFREQ_MINSPEED:
break;
}
}
static int
cpufreq_init(void)
{
int policy;
/* Create device object */
cpufreq_dev = device_create(&cpufreq_io, "cpufreq", DF_CHR);
ASSERT(cpufreq_dev);
dvs_init();
policy = pm_getpolicy();
if (policy == PM_POWERSAVE)
dvs_enable();
return 0;
}