taihu.s

利用开发板上的/dev/mem设备,进行内存映射,驱动cpu的GPIO口,点亮和熄灭led灯.附makefile文件

#include <config.h>
#include <mpc8xx.h>
#include <ppc4xx.h>
#include <version.h>

#include <ppc_asm.tmpl>
#include <ppc_defs.h>

#include <asm/cache.h>
#include <asm/mmu.h>
	.section ".text"
/*------------------------------------------------------------------------------- */
/* Function:	 out32 */
/* Description:	 Output 32 bits */
/*------------------------------------------------------------------------------- */
	.globl	out32
out32:
	stw	4,0x0000(3)	/*原来是:stw r4,0x0000(r3),但是#include <ppc_asm.tmpl>没成功,就只能直接填写4,3了*/
	blr

/*------------------------------------------------------------------------------- */
/* Function:	 in32 */
/* Description:	 Input 32 bits */
/*------------------------------------------------------------------------------- */
	.globl	in32
in32:
	lwz	3,0x0000(3)
	blr