ipl_startup2.c

来自「i.mx31 3DS平台Nandboot引导程序源码」· C语言 代码 · 共 57 行

#include <string.h>
void *memcpy(void *dest, const void *src, size_t n);
typedef unsigned short u16;
typedef unsigned int u32;
typedef unsigned char u8;

/* These variable come from linker */

extern u32 __end_ipl_startup; 
extern u32 __start_ipl_main; 
extern u32 __end_ipl_main;

extern u32 main(void);

//#define IPL_DEBUG

#ifdef IPL_DEBUG
/* Debug before serial is available */
/* Debug message buffer */
u32     *dbg = (u32 *)0x80010000;       
#define DBG(_msg, _param)       \
        *dbg++ = (u32)_msg;    \
        *dbg++ = (u32)_param;
#else
#define DBG(_msg, _param)  do {} while(0)
#endif

u32 copy_jump_main()
{
        volatile u16     *src;
        volatile u16     *dst;
        u32     len;
        u32     (*fptr)(void);
        u32     ret;
        volatile int tmp;


        src = (u16 *)&__end_ipl_startup;
        dst = (u16 *)&__start_ipl_main;
        len = (&__end_ipl_main - &__start_ipl_main) * 2;

        DBG(1, src);
        DBG(2, dst);
        DBG(3, &__end_ipl_main);
        DBG(4, len);

       while (len-- > 0)
        {
                *dst++ = *src++;
        } 

        asm("ldr r1, =main");
        asm("blx r1");
        /* Should never return here! */
}