mirror of
https://github.com/torvalds/linux.git
synced 2024-11-16 17:12:06 +00:00
61 lines
1.1 KiB
C
61 lines
1.1 KiB
C
/*
|
|
* Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
|
|
* Mostly copied from arch/x86/lib/delay.c
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/delay.h>
|
|
#include <asm/param.h>
|
|
|
|
void __delay(unsigned long loops)
|
|
{
|
|
asm volatile(
|
|
"test %0,%0\n"
|
|
"jz 3f\n"
|
|
"jmp 1f\n"
|
|
|
|
".align 16\n"
|
|
"1: jmp 2f\n"
|
|
|
|
".align 16\n"
|
|
"2: dec %0\n"
|
|
" jnz 2b\n"
|
|
"3: dec %0\n"
|
|
|
|
: /* we don't need output */
|
|
: "a" (loops)
|
|
);
|
|
}
|
|
EXPORT_SYMBOL(__delay);
|
|
|
|
inline void __const_udelay(unsigned long xloops)
|
|
{
|
|
int d0;
|
|
|
|
xloops *= 4;
|
|
asm("mull %%edx"
|
|
: "=d" (xloops), "=&a" (d0)
|
|
: "1" (xloops), "0"
|
|
(loops_per_jiffy * (HZ/4)));
|
|
|
|
__delay(++xloops);
|
|
}
|
|
EXPORT_SYMBOL(__const_udelay);
|
|
|
|
void __udelay(unsigned long usecs)
|
|
{
|
|
__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
|
|
}
|
|
EXPORT_SYMBOL(__udelay);
|
|
|
|
void __ndelay(unsigned long nsecs)
|
|
{
|
|
__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
|
|
}
|
|
EXPORT_SYMBOL(__ndelay);
|