start.s

bootup code for Barebone, it s useful for bring up new chip

/*
 * Copyright (C) 2001 MontaVista Software Inc.
 * Author: Jun Sun, [e-mail] or [e-mail]
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 *
 */

#include "regdef.h"
#include "cp0regdef.h"
#include "asm.h"

LEAF(_start)
	
	.set	mips2
	.set	reorder

	/* Disable interrupts */
	mtc0	zero, CP0_STATUS

        /* Disable watch exception. */
        mtc0    zero, CP0_WATCHLO
        mtc0    zero, CP0_WATCHHI

	/* disable kernel mode cache */
	mfc0	t0, CP0_CONFIG
	and	t0, ~0x7
	ori	t0, 0x2
	mtc0	t0, CP0_CONFIG

	/* set up stack */
	li	sp, 0xa0000000 + RAMSIZE - 16
	
	/* jump to main */
	jal	main
			
loop:
	j	loop
	nop
END(_start)