hello???
2010/7/29 yaojin liu lanmanck@gmail.com
hi,all: I encounter strange thing again. :(
it seems the vsprintf will overrun. have someone met before?
To debug it ,I define a function writing character directly to the register: "u_sendstring()"
Here is the code for debugging printf:
void printf(const char *fmt, ...)
{
va_list args;
uint i;
char printbuffer[CONFIG_SYS_PBSIZE];
va_start(args, fmt);
/* For this to work, printbuffer must be larger than
- anything we ever want to print.
*/
u_sendstring("printf2\n");
i = vsprintf(printbuffer, fmt, args);
u_sendstring("printf3\n");
va_end(args);
puts(printbuffer);
}
and here is the output:
DM3xx=>>: DONEprintf2
DM3xx=>>: printf3
DM3xx=>>: U-Boot 2009.03 ( 2010 - 23:14:17)
DM3xx=>>: I2C: ready
DM3xx=>>: DRAM: printf2
DM3xx=>>: printf3
DM3xx=>>: 128printf2
DM3xx=>>: printf3
DM3xx=>>: MB
DM3xx=>>: NAND: board_nand_init end
DM3xx=>>: nand_scan1
DM3xx=>>: nand_scan_ident1
DM3xx=>>: nand_scan_ident2
DM3xx=>>: nand_get_flash_type1
DM3xx=>>: nand_get_flash_type2
DM3xx=>>: nand_get_flash_type4
DM3xx=>>: printf2n BOOTME
DM3xx=>>: BOOTME
DM3xx=>>: BOOTME
DM3xx=>>: BOOTME
/////////////////////// weill, you can see that the first string will output correctly,such as "128" "MB", but when it ran to nand_get_flash_type(), the chip reboot.
static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, struct nand_chip *chip, int busw, int *maf_id)
{
struct nand_flash_dev *type = NULL;
int i, dev_id, maf_idx;
int tmp_id, tmp_manf;
/* Select the device */
chip->select_chip(mtd, 0);
u_sendstring("nand_get_flash_type1\n");
.....
u_sendstring("nand_get_flash_type4\n");
printk("NAND device: Manufacturer ID:"
" 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id, dev_id, nand_manuf_ids[maf_idx].name, type->name);u_sendstring("nand_get_flash_type5\n");
return type;
}
printk is just printf. So as i describe above, the code ran to vsprintf and no respond anymore. How could this happen? Is it another hardware bug?