参考http://cgxcn.blog.163.com/blog/static/132312422009101133251202/

参考：http://blog.chinaunix.net/uid-14833587-id-76499.html

参考：http://lixuefeng26.blog.sohu.com/204383842.html

原理就是：uboot将要传递的参数，保存到一个指定的物理位置；然后linux从该物理位置获取数据即可

1.先看一下uboot自带的参数传递过程：

A． 首先说明两个结构体：

boot/u-boot/include/asm-mips

typedef    struct       global_data {

bd_t          *bd;

unsigned long  flags;

unsigned long  baudrate;

unsigned long  have_console; /* serial_init() was called */

unsigned long  ram_size;         /* RAM size */

unsigned long  reloc_off; /* Relocation Offset */

unsigned long  env_addr;         /* Address  of Environment struct */

unsigned long  env_valid;         /* Checksum of Environment valid? */

void           **jt;          /* jump table */

} gd_t

和

boot/u-boot/include/asm-mips

typedef struct bd_info {

int              bi_baudrate;    /* serial console baudrate */

unsigned long  bi_ip_addr;       /* IP Address */

unsigned char  bi_enetaddr[6];        /* Ethernet adress */

unsigned long  bi_arch_number;     /* unique id for this board */

unsigned long  bi_boot_params;     /* where this board expects params */

unsigned long  bi_memstart;  /* start of DRAM memory */

unsigned long  bi_memsize;    /* size      of DRAM memory in bytes */

unsigned long  bi_flashstart;   /* start of FLASH memory */

unsigned long  bi_flashsize;     /* size  of FLASH memory */

unsigned long  bi_flashoffset; /* reserved area for startup monitor */

} bd_t;

B． 在do_bootm_linux（boot/u-boot/lib_mips/mips_linux.c）中，有如下处理：

字节的空间，来存放要传递的参数。