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/*
* MC9328MXL Intererrupt handler
*
* Copyright (c) 2002 by Jay Monkman <jtm@lopingdog.com>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
*
* http://www.rtems.com/license/LICENSE.
*
*
* $Id$
*/
#define __asm__
/*
* BSP specific interrupt handler for INT or FIQ. In here
* you do determine which interrupt happened and call its
* handler.
*/
.globl bsp_interrupt_dispatch
bsp_interrupt_dispatch :
/*
* Look at interrupt status register to determine source.
* From source, determine offset into expanded vector table
* and load handler address into r0.
*/
ldr r0, =0x00223040 /* Read the vector number */
ldr r1, [r0]
mov r1, r1, LSR #16 /* get the NIVECTOR into 16 LSbits */
/* find the ISR's address based on the vector */
ldr r0, =bsp_vector_table
mov r1, r1, LSL #3 /* Shift vector to get offset into table */
add r1, r0, r1 /* r1 has address of vector entry */
ldr r0, [r1, #4] /* Get the data pointer */
ldr r1, [r1] /* Get the vector */
stmdb sp!,{lr}
ldr lr, =IRQ_return /* prepare the return from handler */
mov pc, r1 /* EXECUTE INT HANDLER */
IRQ_return:
ldmia sp!,{lr}
mov pc, lr
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