Chinaunix首页 | 论坛 | 博客
  • 博客访问: 176539
  • 博文数量: 34
  • 博客积分: 0
  • 博客等级: 民兵
  • 技术积分: 374
  • 用 户 组: 普通用户
  • 注册时间: 2013-10-30 10:46
文章分类

全部博文(34)

文章存档

2018年(5)

2015年(13)

2014年(13)

2013年(3)

我的朋友

分类: 嵌入式

2013-10-30 11:04:31

转载原文路径:http://blog.csdn.net/abc47bca/article/details/6306005

原文内容:

ntroduction:

=====

 

The idea is to build a mini u-boot(same as UBL in Davinci?) out of the u-boot tree that fits into SoC's internal SRAM (<=64K) and bootloads the real u-boot into the SDRAM, then the real u-boot will load the kernel into the SDRAM and boot it. :-).

 

Such a mini u-boot is typically called SPL(Second Program Loader) in u-boot terminology.

 

Duty of SPL:

=====

 

1> Basic ARM initialization

2> UART console initialization

3> Clocks and DPLL locking (minimal)

4> SDRAM initialization

5> Mux (minimal)

6> BootDevice initialization(based on where we are booting from.MMC1/MMC2/Nand/Onenand)

7> Bootloading real u-boot from the BootDevice and passing control to it.

 

BTW:

TI's X-loader is just one implemention of SPL out of the u-boot tree, And it depends on the u-boot source tree. same framework with u-boot. The u-boot guys will implement their own SPL in the tree. and then our system will boot without x-loader's help. :-)

 

 

Reference:

 


阅读(1577) | 评论(0) | 转发(0) |
0

上一篇:没有了

下一篇:uboot 跳转入ram执行代码分析(重映射分析)

给主人留下些什么吧!~~