[U-Boot-Users] Bug in fat_register_device() ?

hs at denx.de
2007-06-04T15:18:41Z

Hello,

I have on a CF Card a MBR with "FAT" on offset 0x36 (sektor 0). The actual
U-Boot Code assumes know, that this is a PBR, but it is a MBR ... So I prefer
First to check, if it is a valid MBR, and if not, check if it is maybe a PBR.
Like the following Patch:

diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index a823b5a..d0e99ec 100644
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -83,23 +83,25 @@ fat_register_device(block_dev_desc_t *dev_desc, int part_no)
/* no signature found */
return -1;
}
- if(!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET],"FAT",3)) {
- /* ok, we assume we are on a PBR only */
- cur_part = 1;
- part_offset=0;
- }
- else {
#if (CONFIG_COMMANDS & CFG_CMD_IDE) || (CONFIG_COMMANDS & CFG_CMD_SCSI) || \
(CONFIG_COMMANDS & CFG_CMD_USB) || defined(CONFIG_SYSTEMACE)
+ {
disk_partition_t info;
if(!get_partition_info(dev_desc, part_no, &info)) {
part_offset = info.start;
cur_part = part_no;
}
else {
- printf ("** Partition %d not valid on device %d **\n",part_no,dev_desc->dev);
- return -1;
+ if(!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET],"FAT",3)) {
+ /* ok, we assume we are on a PBR only */
+ cur_part = 1;
+ part_offset=0;
+ } else {
+ printf ("** Partition %d not valid on device %d **\n",part_no,dev_desc->dev);
+ return -1;
+ }
}
+ }
#else
/* FIXME we need to determine the start block of the
* partition where the DOS FS resides. This can be done
@@ -109,7 +111,6 @@ fat_register_device(block_dev_desc_t *dev_desc, int part_no)
part_offset=32;
cur_part = 1;
#endif
- }
return 0;
}

Some comments? Other ways to distinguish between a MBR or PBR?

Best regards
Heiko Schocher