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/*
* linux/arch/arm/mach-pxa/pxa25x.c
*
* Author: Nicolas Pitre
* Created: Jun 15, 2001
* Copyright: MontaVista Software Inc.
*
* Code specific to PXA21x/25x/26x variants.
*
* 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.
*
* Since this file should be linked before any other machine specific file,
* the __initcall() here will be executed first. This serves as default
* initialization stuff for PXA machines which can be overridden later if
* need be.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <asm/hardware.h>
#include <asm/arch/pxa-regs.h>
#include "generic.h"
/*
* Various clock factors driven by the CCCR register.
*/
/* Crystal Frequency to Memory Frequency Multiplier (L) */
static unsigned char L_clk_mult[32] = { 0, 27, 32, 36, 40, 45, 0, };
/* Memory Frequency to Run Mode Frequency Multiplier (M) */
static unsigned char M_clk_mult[4] = { 0, 1, 2, 4 };
/* Run Mode Frequency to Turbo Mode Frequency Multiplier (N) */
/* Note: we store the value N * 2 here. */
static unsigned char N2_clk_mult[8] = { 0, 0, 2, 3, 4, 0, 6, 0 };
/* Crystal clock */
#define BASE_CLK 3686400
/*
* Get the clock frequency as reflected by CCCR and the turbo flag.
* We assume these values have been applied via a fcs.
* If info is not 0 we also display the current settings.
*/
unsigned int get_clk_frequency_khz(int info)
{
unsigned long cccr, turbo;
unsigned int l, L, m, M, n2, N;
cccr = CCCR;
asm( "mrc\tp14, 0, %0, c6, c0, 0" : "=r" (turbo) );
l = L_clk_mult[(cccr >> 0) & 0x1f];
m = M_clk_mult[(cccr >> 5) & 0x03];
n2 = N2_clk_mult[(cccr >> 7) & 0x07];
L = l * BASE_CLK;
M = m * L;
N = n2 * M / 2;
if(info)
{
L += 5000;
printk( KERN_INFO "Memory clock: %d.%02dMHz (*%d)\n",
L / 1000000, (L % 1000000) / 10000, l );
M += 5000;
printk( KERN_INFO "Run Mode clock: %d.%02dMHz (*%d)\n",
M / 1000000, (M % 1000000) / 10000, m );
N += 5000;
printk( KERN_INFO "Turbo Mode clock: %d.%02dMHz (*%d.%d, %sactive)\n",
N / 1000000, (N % 1000000) / 10000, n2 / 2, (n2 % 2) * 5,
(turbo & 1) ? "" : "in" );
}
return (turbo & 1) ? (N/1000) : (M/1000);
}
EXPORT_SYMBOL(get_clk_frequency_khz);
/*
* Return the current memory clock frequency in units of 10kHz
*/
unsigned int get_memclk_frequency_10khz(void)
{
return L_clk_mult[(CCCR >> 0) & 0x1f] * BASE_CLK / 10000;
}
EXPORT_SYMBOL(get_memclk_frequency_10khz);
/*
* Return the current LCD clock frequency in units of 10kHz
*/
unsigned int get_lcdclk_frequency_10khz(void)
{
return get_memclk_frequency_10khz();
}
EXPORT_SYMBOL(get_lcdclk_frequency_10khz);
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