/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 1994 by Waldorf Electronics * Copyright (C) 1995 - 2000, 01, 03 by Ralf Baechle * Copyright (C) 1999, 2000 Silicon Graphics, Inc. */#ifndef _ASM_DELAY_H#define _ASM_DELAY_H#include <linux/param.h>#include <linux/smp.h>#include <asm/compiler.h>static inline void __delay(unsigned long loops){ if (sizeof(long) == 4) __asm__ __volatile__ ( " .set noreorder \n" " .align 3 \n" "1: bnez %0, 1b \n" " subu %0, 1 \n" " .set reorder \n" : "=r" (loops) : "0" (loops)); else if (sizeof(long) == 8) __asm__ __volatile__ ( " .set noreorder \n" " .align 3 \n" "1: bnez %0, 1b \n" " dsubu %0, 1 \n" " .set reorder \n" : "=r" (loops) : "0" (loops));}/* * Division by multiplication: you don't have to worry about * loss of precision. * * Use only for very small delays ( < 1 msec). Should probably use a * lookup table, really, as the multiplications take much too long with * short delays. This is a "reasonable" implementation, though (and the * first constant multiplications gets optimized away if the delay is * a constant) */static inline void __udelay(unsigned long usecs, unsigned long lpj){ unsigned long lo; /* * The rates of 128 is rounded wrongly by the catchall case * for 64-bit. Excessive precission? Probably ... */#if defined(CONFIG_64BIT) && (HZ == 128) usecs *= 0x0008637bd05af6c7UL; /* 2**64 / (1000000 / HZ) */#elif defined(CONFIG_64BIT) usecs *= (0x8000000000000000UL / (500000 / HZ));#else /* 32-bit junk follows here */ usecs *= (unsigned long) (((0x8000000000000000ULL / (500000 / HZ)) + 0x80000000ULL) >> 32);#endif if (sizeof(long) == 4) __asm__("multu\t%2, %3" : "=h" (usecs), "=l" (lo) : "r" (usecs), "r" (lpj) : GCC_REG_ACCUM); else if (sizeof(long) == 8) __asm__("dmultu\t%2, %3" : "=h" (usecs), "=l" (lo) : "r" (usecs), "r" (lpj) : GCC_REG_ACCUM); __delay(usecs);}#define __udelay_val cpu_data[smp_processor_id()].udelay_val#define udelay(usecs) __udelay((usecs),__udelay_val)/* make sure "usecs *= ..." in udelay do not overflow. */#if HZ >= 1000#define MAX_UDELAY_MS 1#elif HZ <= 200#define MAX_UDELAY_MS 5#else#define MAX_UDELAY_MS (1000 / HZ)#endif#endif /* _ASM_DELAY_H */
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 by Waldorf Electronics
* Copyright (C) 1995 - 2000, 01, 03 by Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_DELAY_H
#define _ASM_DELAY_H
#include <linux/param.h>
#include <linux/smp.h>
#include <asm/compiler.h>
static inline void __delay(unsigned long loops)
{
if (sizeof(long) == 4)
__asm__ __volatile__ (
" .set noreorder \n"
" .align 3 \n"
"1: bnez %0, 1b \n"
" subu %0, 1 \n"
" .set reorder \n"
: "=r" (loops)
: "0" (loops));
else if (sizeof(long) == 8)
__asm__ __volatile__ (
" .set noreorder \n"
" .align 3 \n"
"1: bnez %0, 1b \n"
" dsubu %0, 1 \n"
" .set reorder \n"
: "=r" (loops)
: "0" (loops));
}
/*
* Division by multiplication: you don't have to worry about
* loss of precision.
*
* Use only for very small delays ( < 1 msec). Should probably use a
* lookup table, really, as the multiplications take much too long with
* short delays. This is a "reasonable" implementation, though (and the
* first constant multiplications gets optimized away if the delay is
* a constant)
*/
static inline void __udelay(unsigned long usecs, unsigned long lpj)
{
unsigned long lo;
/*
* The rates of 128 is rounded wrongly by the catchall case
* for 64-bit. Excessive precission? Probably ...
*/
#if defined(CONFIG_64BIT) && (HZ == 128)
usecs *= 0x0008637bd05af6c7UL; /* 2**64 / (1000000 / HZ) */
#elif defined(CONFIG_64BIT)
usecs *= (0x8000000000000000UL / (500000 / HZ));
#else /* 32-bit junk follows here */
usecs *= (unsigned long) (((0x8000000000000000ULL / (500000 / HZ)) +
0x80000000ULL) >> 32);
#endif
if (sizeof(long) == 4)
__asm__("multu\t%2, %3"
: "=h" (usecs), "=l" (lo)
: "r" (usecs), "r" (lpj)
: GCC_REG_ACCUM);
else if (sizeof(long) == 8)
__asm__("dmultu\t%2, %3"
: "=h" (usecs), "=l" (lo)
: "r" (usecs), "r" (lpj)
: GCC_REG_ACCUM);
__delay(usecs);
}
#define __udelay_val cpu_data[smp_processor_id()].udelay_val
#define udelay(usecs) __udelay((usecs),__udelay_val)
/* make sure "usecs *= ..." in udelay do not overflow. */
#if HZ >= 1000
#define MAX_UDELAY_MS 1
#elif HZ <= 200
#define MAX_UDELAY_MS 5
#else
#define MAX_UDELAY_MS (1000 / HZ)
#endif
#endif /* _ASM_DELAY_H */