cmd: gpt: backup boot code before writing MBR

On some cases the first 440 bytes of MBR are used to keep an additional
information for ROM boot loader. 'gpt write' command doesn't preserve
that area and makes boot code gone.

Preserve boot code area when run 'gpt write' command.

Signed-off-by: Vincent Tinelli <vincent.tinelli@intel.com>
Signed-off-by: Brennan Ashton <brn@deako.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Vincent Tinelli 2017-01-30 15:46:07 +03:00 committed by Tom Rini
parent d726f225f5
commit e163a931af

View file

@ -324,6 +324,13 @@ static int set_protective_mbr(struct blk_desc *dev_desc)
printf("%s: calloc failed!\n", __func__); printf("%s: calloc failed!\n", __func__);
return -1; return -1;
} }
/* Read MBR to backup boot code if it exists */
if (blk_dread(dev_desc, 0, 1, p_mbr) != 1) {
error("** Can't read from device %d **\n", dev_desc->devnum);
return -1;
}
/* Append signature */ /* Append signature */
p_mbr->signature = MSDOS_MBR_SIGNATURE; p_mbr->signature = MSDOS_MBR_SIGNATURE;
p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT; p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;