As the reset vector is located at 0xfffffffc, all flash sectors from the
beginning of the U-Boot binary to 0xffffffff must be protected. On the
TQM8548-AG having small sectors at the end of the flash it happened that
the last two sector were not protected and an "erase all" left an
un-bootable system behind:
Bank # 2: CFI conformant FLASH (32 x 16) Size: 32 MB in 270 Sectors
AMD Standard command set, Manufacturer ID: 0xEC, Device ID: 0x257E
Erase timeout: 8192 ms, write timeout: 1 ms
FFFA0000 E RO
FFFC0000 RO
FFFE0000 RO
FFFE4000 RO
FFFE8000 RO
FFFEC000 RO
FFFF0000 RO
FFFF4000 RO
FFFF8000 E
FFFFC000
The same bug seems to be in drivers/mtd/cfi_flash.c:flash_init() and many
board BSPs as well.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
/* Monitor protection ON by default */
flash_protect (FLAG_PROTECT_SET,
- CONFIG_SYS_MONITOR_BASE,
- CONFIG_SYS_MONITOR_BASE + monitor_flash_len - 1,
+ CONFIG_SYS_MONITOR_BASE, 0xffffffff,
&flash_info[CONFIG_SYS_MAX_FLASH_BANKS - 1]);
/* Environment protection ON by default */