Uboot對非Linux kernel的引導

實現了uboot對非linux kernel的引導。雖然有一個IH_TYPE_STANDALONE，但是沒有實現。nnd。只能自己想辦法。實現詳細見下面。

1、兩個命令

set bootcmd tftp 84000000 uImage;bootm 84000000

set bootdelay 1

2、非linux kernel的引導實現方法：

一共三個函數： jump，selectboot 和 system_boot

把jump放在需要跳轉的地方，參數就是要跳轉的地址。然后返回，重啟系統。select放在main的開頭。通過判斷ram的特定地址的特定信息實現跳轉。

system_boot實現系統的重新啟動

#define FDMA_SRAM_TOP_ADDRESS 0xB9229800

#define MAGIC_NUM 0x71097100

#define DEAD_PATTERN 0xBAD0BADF

#define ST40_CPG_REGS_BASE 0xFFC00000#define

ST40_CPG_WTCNT (ST40_CPG_REGS_BASE + 0x08)

#define ST40_CPG_WTCSR (ST40_CPG_REGS_BASE + 0x0C)

#define ST40_CPG_WTCSR2 (ST40_CPG_REGS_BASE + 0x1C)

void Jump(unsigned int address)

{

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*1, MAGIC_NUM);

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*2, address);

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*3, ~address);

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*4, ~MAGIC_NUM);

STSYS_WriteRegDev16LE(ST40_CPG_WTCNT, 0x5AF0); /*Watchdog counter*/

STSYS_WriteRegDev16LE(ST40_CPG_WTCSR, 0xA547); /*Watchdog control*/

STSYS_WriteRegDev16LE(ST40_CPG_WTCSR2, 0xAA00); /*Watchdog control2*/

STSYS_WriteRegDev16LE(ST40_CPG_WTCSR, 0xA5C7); /*Start watchdog counter*/ for(;;);

}

void SelectBoot(void)

{

unsigned int MagicNum = 0;

unsigned int NotMagicNum = 0;

unsigned int JumpAddress = 0;

unsigned int NotJumpAddress = 0; void (*entry)(void);

/* entry=0xa0100000;

entry();*/ //if((STSYS_ReadRegDev16LE(ST40_CPG_WTCSR2) 0xFF) != 0x0)

{

MagicNum = STSYS_ReadRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*1);

JumpAddress = STSYS_ReadRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*2);

NotJumpAddress = STSYS_ReadRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*3);

NotMagicNum = STSYS_ReadRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*4);

if((MagicNum == MAGIC_NUM)

(MagicNum == (~NotMagicNum))

(JumpAddress == (~NotJumpAddress)))

{

entry = (void (*)(void))JumpAddress;

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*1, DEAD_PATTERN);

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*2, DEAD_PATTERN);

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*3, DEAD_PATTERN);

STSYS_WriteRegDev32LE(FDMA_SRAM_TOP_ADDRESS - 4*4, DEAD_PATTERN);

#if 0/*Setup For watchdog in case jump failed.*/

STSYS_WriteRegDev16LE(ST40_CPG_WTCNT, 0x5AF0);

STSYS_WriteRegDev16LE(ST40_CPG_WTCSR, 0xA543);

STSYS_WriteRegDev16LE(ST40_CPG_WTCSR2, 0xAA01);

STSYS_WriteRegDev16LE(ST40_CPG_WTCSR, 0xA5C7);

#endif entry(); while(1);

}

}

}void system_reboot(void)

{

ulong sr;

asm (stc sr, %0:=r (sr));

sr 　= (1 28); /* set block bit */

asm (ldc %0, sr: :r (sr));

asm volatile (trapa #0);

}