移植u-boot到mini2440--用openjtag加载

  到现在已经把 u-boot 启动代码大概过了一遍，可以开始尝试从 openjtag 加载启动了。
配置方式 include/configs/mini2440.h：

#define CONFIG_SKIP_LOWLEVEL_INIT
#define CONFIG_SYS_TEXT_BASE /*0x0*/ 0x33F80000

然后make menuconfig 还要一个选项 Use private libgcc：

  因为刚开始我没选择这个选项，在做除法运算的时候链接了工具链的除法库，导致生成的代码有armv5指令集，而 s3c2440 属于 arm920t 只支持 armv4 指令集，就出现了异常指令。
编译之后用命令行：

arm-linux-gdb -x s3c2440_gdb.init u-boot

开启调试。

可见u-boot可以正常启动：

  这里附上 s3c2440_gdb.init 脚本代码。主要是初始化dram。

target remote 127.0.0.1:3333

monitor reset

monitor halt

monitor wait_halt

monitor arm920t cp15 2 0

monitor step



echo Configuring system...\n

#disable watchdog

monitor mww 0x53000000 0



#disalbe interrupt --- int-mask register 

monitor mww 0x4A000008 0xFFFFFFFF



#disalbe interrupt --- int-sub-mask register 

monitor mww 0x4A00001C 0x7FFF 



#initialize system clocks --- locktime register

monitor mww 0x4C000000 0xFF000000



#initialize system clocks --- clock-divn register

#CLKDVIN_400_148£¬Èç¹ûÊÇS3C2410(1:2:4), žÄΪ0x3

monitor mww 0x4C000014 0x5



#initialize system clocks --- upll register

# Èç¹ûÊÇS3C2410£¬žÄΪ0x280102

monitor mww 0x4C000008 0x38022



#initialize system clocks --- mpll register

# 12M for FCLK=400M, Èç¹ûÊÇS3C2410(200MHz)£¬žÄΪ0x5c0400

monitor mww 0x4C000004 0x5c011



#setup memory controller

echo Configuring the SDRAM controller...\n

#conw

monitor mww 0x48000000 0x2201d110

#bank0

monitor mww 0x48000004 0x00000700

#bank1

monitor mww 0x48000008 0x00000700

#bank2

monitor mww 0x4800000c 0x00000700

#bank3

monitor mww 0x48000010 0x00001f4c

#bank4

monitor mww 0x48000014 0x00001f88

#bank5

monitor mww 0x48000018 0x00007ffc

#bank6

monitor mww 0x4800001c 0x00018005

#bank7

monitor mww 0x48000020 0x00018005

#vREFRESH HCLK=100MHz

monitor mww 0x48000024 0x008C04F4

#vBANKSIZE

monitor mww 0x48000028 0xB1

#vMRSRB6

monitor mww 0x4800002c 0x30

#vMRSRB7

monitor mww 0x48000030 0x30



#load

#break main

#continue