Booting from NOR Flash Failure

echo tong

Prodigy 45 points

Other Parts Discussed in Thread: AM3715

I am using a board with CPU(TI AM3715). A NOR Flash(Micron PC28F512G18FF) attaches to GPMC CS0.

The CPU can not boot from the NOR Flash.

The operations are following,

Step 1: sys_boot[4:0] = 0b00110, boot from MMC1.

Configure the registers GPMC_CONFIGi_0(i=1,2,...7) related to CS0 in U-BOOT.

CS0 CONFIG 1: 0xe9401213

CS0 CONFIG 2: 0x000c1503

CS0 CONFIG 3: 0x00050503

CS0 CONFIG 4: 0x0b051506

CS0 CONFIG 5: 0x020e0c15

CS0 CONFIG 6: 0x0b0603c3

CS0 CONFIG 7: 0x00000c50

Copy x-load.bin to NOR Flash through the commands below.

OMAP3_Mulan # protect off all Un-Protect Flash Bank # 1

OMAP3_Mulan # erase 0x10000000 0x1003FFFF

. done

Erased 1 sectors

OMAP3_Mulan # mmc init mmc1 is available

OMAP3_Mulan # fatload mmc 0 0x80800000 MLO reading MLO

17788 bytes read

OMAP3_Mulan # cp.b 0x80800000 0x10000000 0x457C

Copy to Flash... done

Check data on the first sector of the NOR Flash through the following command,

OMAP3_Mulan # md 0x10000000 0x457C

The data on the first sector of the NOR Flash is the same as x-load.bin.

Step 2: sys_boot[4:0] = 0b01110, boot from NOR Flash.

After CPU powers on, the debug UART prints NOTHING.

I think that the CPU does not boot from NOR Flash.

Step 3: sys_boot[4:0] = 0b00110, boot from MMC1.

Added source code in the function void start_armboot (void) in the file lib/board.c in x-load.

void start_armboot (void)

{

init_fnc_t **init_fnc_ptr;

int i;

uchar *buf;

for (init_fnc_ptr = init_sequence; *init_fnc_ptr; ++init_fnc_ptr) {

if ((*init_fnc_ptr)() != 0) {

hang ();

}

misc_init_r();

buf = (uchar*) CFG_LOADADDR;

/* Added source code below to get the register value related to GPMC_CONFIG CS0 and read x-load from NOR Flash */

#if 1

u32 temp;

#define __raw_readl(a) (*(volatile unsigned int *)(a))

#define __raw_writel(v,a) (*(volatile unsigned int *)(a) = (v))

#define __raw_readw(a) (*(volatile unsigned short *)(a))

#define __raw_writew(v,a) (*(volatile unsigned short *)(a) = (v))

#define BIT0 (1<<0)

#define BIT1 (1<<1)

#define BIT2 (1<<2)

#define BIT3 (1<<3)

#define BIT4 (1<<4)

#define BIT5 (1<<5)

#define SYSBOOT_MASK (BIT0|BIT1|BIT2|BIT3|BIT4)

/************************************************

* get_sysboot_value(void) - return SYS_BOOT[4:0]

************************************************/

int mode;

mode = __raw_readl(CONTROL_STATUS) & (SYSBOOT_MASK);

printf("SYS_BOOT: 0x%08x\n", mode);

i = 1;

temp = __raw_readl(GPMC_CONFIG1 + GPMC_CONFIG_CS0);