52 lines
1.1 KiB
C
52 lines
1.1 KiB
C
/* MN10300 Short delay interpolation routines
|
|
*
|
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/delay.h>
|
|
#include <asm/div64.h>
|
|
|
|
/*
|
|
* basic delay loop
|
|
*/
|
|
void __delay(unsigned long loops)
|
|
{
|
|
int d0;
|
|
|
|
asm volatile(
|
|
" bra 1f \n"
|
|
" .align 4 \n"
|
|
"1: bra 2f \n"
|
|
" .align 4 \n"
|
|
"2: add -1,%0 \n"
|
|
" bne 2b \n"
|
|
: "=&d" (d0)
|
|
: "0" (loops)
|
|
: "cc");
|
|
}
|
|
EXPORT_SYMBOL(__delay);
|
|
|
|
/*
|
|
* handle a delay specified in terms of microseconds
|
|
*/
|
|
void __udelay(unsigned long usecs)
|
|
{
|
|
unsigned long start, stop, cnt;
|
|
|
|
/* usecs * CLK / 1E6 */
|
|
stop = __muldiv64u(usecs, MN10300_TSCCLK, 1000000);
|
|
start = TMTSCBC;
|
|
|
|
do {
|
|
cnt = start - TMTSCBC;
|
|
} while (cnt < stop);
|
|
}
|
|
EXPORT_SYMBOL(__udelay);
|