[U-Boot] Not able read more than 12kb with fatload command

[sadashiva reddy]

 *Hi Sir,*
**
*    I am able read 12kb size into my memory using below command *
**
*=> fatload usb 0:1 400000 debug.txt 3000
reading debug.txt*
*12288 bytes read*
**
*   but I give same command even one byte more the board crashes and
restarts.*
**
*suppose if I given *

=> fatload usb 0:1 400000 debug.txt 3001
reading debug.txt
Device NOT ready
   Request Sense returned 00 00 00
12289 bytes read
Machine Check Exception.
Caused by (from msr): regs 07b693e8 Data machine check.
NIP: 00000000 XER: 20000000 LR: 07FA1D60 REGS: 07b693e8 TRAP: 0200 DEAR:
00000000
MSR: 00000000 EE: 0 PR: 0 FP: 0 ME: 0 IR/DR: 00
GPR00: CFDFC648 07B694D8 07B69724 07FB64EC 07FB64F5 07B69518 07FFB72C
00000010
GPR08: FFFFFFFF 00264000 00000020 00000012 42022082 00000000 00000000
00000000
GPR16: 07FC6664 00000000 00000000 07FB3AF8 07FB3AF8 00000000 00000000
0DF7D828
GPR24: 0129FCAE 0129FCAE 07FFB72C 07B69518 00000000 07FB64ED 07FCAABC
00000000
Call backtrace:
00000000 07F7B9E0 07F7BE0C 07F7308C 07F8567C 07F84BB0 07F84DBC
07F89534 07F6EFFC 07F6C5F4
machine check

U-Boot 2011.03 (Oct 28 2011 - 15:52:40)
(c) MIP405, MIP405 - 001 released
CPU:   AMCC PowerPC 405GPr Rev. B at 396 MHz (PLB=132 OPB=66 EBC=33)
       Internal PCI arbiter enabled, PCI sync clock at 33 MHz
       16 kB I-Cache 16 kB D-Cache
Board: ### No HW ID - assuming MIP405-8 Rev A Boot Config: 0x80
I2C:   ready
DRAM:  REFRESH, Need to revisit128 MiB
Boot:  FLASH
Flash: 8 MiB
  ### pci_pip405_fixup_irq entered
  ### pci_pip405_fixup_irq entered
  ### pci_pip405_fixup_irq entered
  ### pci_pip405_fixup_irq entered
Net:   ppc_4xx_eth0
IDE:   Bus 0: not available
Rev:   MIP405-8 Rev A PLD 1 Vers 1
Can't overwrite "ethaddr"
INFO:  old environment ajusted, use saveenv
Hit any key to stop autoboot:  5 4 3 2 1 0

*This I am trynig to do with USB operations. If I format the pen drive with
ext2 type and copy the image or text file into pen drive*
*and use the below command like.*

=> ext2load usb 0:1 400000 vxWorks.img
Loading file "vxWorks.img" from usb device 0:1 (usbda1)
458887 bytes read.

Can you please help reading the fatload command issue.
Thanks in advance.

Best Regards,
Sadashiv