linux-imx

/*

 * (C) 2004-2006  Sebastian Witt <se.witt@gmx.net>

 *

 *  Licensed under the terms of the GNU GPL License version 2.

 *  Based upon reverse engineered information

 *

 *  BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/init.h>

#include <linux/cpufreq.h>

#include <linux/pci.h>

#include <linux/delay.h>

​

#define NFORCE2_XTAL 25

#define NFORCE2_BOOTFSB 0x48

#define NFORCE2_PLLENABLE 0xa8

#define NFORCE2_PLLREG 0xa4

#define NFORCE2_PLLADR 0xa0

#define NFORCE2_PLL(mul, div) (0x100000 | (mul << 8) | div)

​

#define NFORCE2_MIN_FSB 50

#define NFORCE2_SAFE_DISTANCE 50

​

/* Delay in ms between FSB changes */

/* #define NFORCE2_DELAY 10 */

​

/*

 * nforce2_chipset:

 * FSB is changed using the chipset

 */

static struct pci_dev *nforce2_dev;

​

/* fid:

 * multiplier * 10

 */

static int fid;

​

/* min_fsb, max_fsb:

 * minimum and maximum FSB (= FSB at boot time)

 */

static int min_fsb;

static int max_fsb;

​

MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>");

MODULE_DESCRIPTION("nForce2 FSB changing cpufreq driver");

MODULE_LICENSE("GPL");

​

module_param(fid, int, 0444);

module_param(min_fsb, int, 0444);

​

MODULE_PARM_DESC(fid, "CPU multiplier to use (11.5 = 115)");

MODULE_PARM_DESC(min_fsb,

        "Minimum FSB to use, if not defined: current FSB - 50");

​

/**

 * nforce2_calc_fsb - calculate FSB

 * @pll: PLL value