uboot: Bad eraseblock 0 at 0x0

I am using TI platform for AM335x, and download SDK from the following URL
http://software-dl.ti.com/sitara_linux/esd/AM335xSDK/06_00_00_00/index_FDS.html

The following is the u-boot initial message.

U-Boot 2013.01.01 (Oct 03 2014 - 16:41:36)
 
I2C:   ready
DRAM:  64 MiB
WARNING: Caches not enabled
Incorrect magic number (0x0) in EEPROM
Could not get board ID.
NAND:  NAND device: Manufacturer ID: 0x20, Chip ID: 0xf1 (ST Micro NAND 128MiB 3,3V 8-bit)
128 MiB
Try Accessing DDR memory
Scanning device for bad blocks
Bad eraseblock 0 at 0x000000000000
Bad eraseblock 1 at 0x000000020000
Bad eraseblock 2 at 0x000000040000
Bad eraseblock 3 at 0x000000060000
.....
.....
Bad eraseblock 175 at 0x0000015e0000

Skipping bad block at  0x00000000                                          
Skipping bad block at  0x00020000                                          
Skipping bad block at  0x00040000                                          
Skipping bad block at  0x00060000                                          
Skipping bad block at  0x00080000    
.....
.....
Skipping bad block at  0x015c0000                                          
Skipping bad block at  0x015e0000

Erasing at 0x1600000 --  17% complete.
Erasing at 0x1700000 --  18% complete.
Erasing at 0x1840000 --  19% complete.
Erasing at 0x1980000 --  20% complete.
...
...
Erasing at 0x7fe0000 -- 100% complete.
Erase OK

It shows a lot of Bad Block information when I do erase or write operation on Nand flash, how do I  solve this issue? Thanks.