According to the UEFI Spec (Table 16, section 5.2.3 of the version 2.4 Errata B), the protective MBR partition record size must be set to the size of the disk minus one, in LBAs.
However, the current code was setting the size as the total number of LBAs on the disk, resulting in an off-by-one error.
This confused the AM335x ROM code, and will probably confuse other tools as well.
Signed-off-by: Maxime Ripard maxime.ripard@free-electrons.com --- disk/part_efi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/disk/part_efi.c b/disk/part_efi.c index 612f0926b62b..5ca17c138e96 100644 --- a/disk/part_efi.c +++ b/disk/part_efi.c @@ -240,7 +240,7 @@ static int set_protective_mbr(block_dev_desc_t *dev_desc) p_mbr->signature = MSDOS_MBR_SIGNATURE; p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT; p_mbr->partition_record[0].start_sect = 1; - p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba; + p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba - 1;
/* Write MBR sector to the MMC device */ if (dev_desc->block_write(dev_desc->dev, 0, 1, p_mbr) != 1) {