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 -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany