I am using u-boot 2017.03 in my system and enabled the debug in fs/fat/fat.c I had a USB disk formatted in FAT16 in Linux, I put a bigfile.bin into / in the USB disk and plugged the disk into by board. Then I want to read/load the bigfile.bin into RAM with u-boot's fatload command, I did followings.
# usb reset # fatls usb 0, it showd, VFAT Support enabled FAT16, fat_sect: 128, fatlength: 128 Rootdir begins at cluster: 0, sector: 384, offset: 30000 Data begins at: 256 Sector size: 512, cluster size: 128 FAT read(sect=384, cnt:2), clust_size=128, DIRENTSPERBLOCK=16 36438016 bigfile.bin 1012 s01syslogd 1004 s02klogd 1876 s02sysctl 1684 s20urandom 214 s21mount END LOOP: buffer_blk_cnt=0 clust_size=128 FAT read(sect=385, cnt:2), clust_size=128, DIRENTSPERBLOCK=16 1635 s30dbus 438 s40network RootDentname == NULL - 13
8 file(s), 0 dir(s) # fatload usb 0 0x100000 bigfile.bin reading bigile.bin VFAT Support enabled FAT16, fat_sect: 128, fatlength: 128 Rootdir begins at cluster: 0, sector: 384, offset: 30000 Data begins at: 256 Sector size: 512, cluster size: 128 FAT read(sect=384, cnt:2), clust_size=128, DIRENTSPERBLOCK=16 Rootvfatname: |bigfile.bin| RootName: bigfile.bin, start: 0x3, size: 0x22c0000 Filesize: 36438016 bytes 36438016 bytes FAT16: entry: 0x0003 = 3, offset: 0x0003 = 3 FAT16: ret: 00000004, offset: 0003 FAT16: entry: 0x0004 = 4, offset: 0x0004 = 4 FAT16: ret: 00000005, offset: 0004 FAT16: entry: 0x0005 = 5, offset: 0x0005 = 5 FAT16: ret: 00000006, offset: 0005 FAT16: entry: 0x0006 = 6, offset: 0x0006 = 6 FAT16: ret: 00000007, offset: 0006 FAT16: entry: 0x0007 = 7, offset: 0x0007 = 7 FAT16: ret: 00000008, offset: 0007 FAT16: entry: 0x0008 = 8, offset: 0x0008 = 8 FAT16: ret: 00000009, offset: 0008 FAT16: entry: 0x0009 = 9, offset: 0x0009 = 9 FAT16: ret: 0000000a, offset: 0009 ..... ..... FAT16: entry: 0x020e = 526, offset: 0x020e = 526 FAT16: ret: 0000020f, offset: 020e FAT16: entry: 0x020f = 527, offset: 0x020f = 527 FAT16: ret: 00000210, offset: 020f FAT16: entry: 0x0210 = 528, offset: 0x0210 = 528 FAT16: ret: 0000ffff, offset: 0210 gc - clustnum: 3, startsect: 640 FAT16: entry: 0x0210 = 528, offset: 0x0210 = 528 FAT16: ret: 0000ffff, offset: 0210 curclust: 0xffff Invalid FAT entry Size: 36438016, got: 34471936
I have tried many times, even with "fatload usb 0 0x100000 bigfile.bin 2000000", it still failed with above error. I can not test newer version of u-boot, since there are lots of old drivers I am using.