stall.s

来自「Windows CE 6.0 BSP for the Beagle Board.」· S 代码 · 共 37 行

;
; Copyright (c) Special Computing.  All rights reserved. 
; Copyright (c) Microsoft Corporation.  All rights reserved.
;
;------------------------------------------------------------------------------
;
;  File:  stall.s

        INCLUDE kxarm.h

        INCLUDE bsp_cfg.inc

        TEXTAREA

;-------------------------------------------------------------------------------
;
;  Function:  OALStall
;
;  This function implements busy stall loop. On entry r0 contains number
;  of microseconds to stall. We assume that system is already on final CPU
;  frequency.
;
        LEAF_ENTRY OALStall

10      ldr     r1, =25 ;BSP_STALL_DELAY
20      subs    r1, r1, #1
        bne     %B20
        subs    r0, r0, #1
        bne     %B10
        bx      lr
        
        ENTRY_END OALStall
        
;------------------------------------------------------------------------------

        END