Subversion Repositories or1k

/*

 *  linux/arch/arm/lib/delay.S

 *

 *  Copyright (C) 1995-2003 Russell King

 *

 * 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 

#include 

#include 

                .text

/*

 * See linux/include/asm-arm/delay.h for a description of the maths.

 */

#if NDELAY_FACTOR > 255

#error NDELAY_FACTOR out of range

#endif

#if UDELAY_FACTOR > 65535

#error UDELAY_FACTOR out of range

#endif

LC0:            .word   SYMBOL_NAME(loops_per_jiffy)

ENTRY(__const_delay)

                ldr     r3, LC0

                mov     r1, r0, lsr #11

                ldr     r2, [r3, #0]

                b       2f

ENTRY(__ndelay)

                mov     r2, #NDELAY_FACTOR

                b       1f

ENTRY(__udelay)

                mov     r2,     #UDELAY_FACTOR & 0xff00

                orr     r2, r2, #UDELAY_FACTOR & 0x00ff

1:              ldr     r3, LC0

                mul     r1, r0, r2

                ldr     r2, [r3, #0]

                mov     r1, r1, lsr #11

2:              mov     r2, r2, lsr #12

                mul     r0, r1, r2

                movs    r0, r0, lsr #5

                RETINSTR(moveq,pc,lr)

/*

 * loops = (r0 * 0x10c6 * HZ * loops_per_jiffy) / 2^32

 *

 * Oh, if only we had a cycle counter...

 */

ENTRY(__delay)

                subs    r0, r0, #1

                bcs     SYMBOL_NAME(__delay)

                RETINSTR(mov,pc,lr)