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Kernel data corruption while flashing u-boot with kobs-ng

Question asked by Ravi Kumar on Mar 29, 2016
Latest reply on Apr 8, 2016 by Ravi Kumar

I am using IMX53 based custom board with micron flash. I have flashed NAND as follows after booting with sdcard, but in Kernel partition (/dev/mtd1) specific memory locations (2002 byte, 4050=2002+2048 byte, 6098=4050+2048 byte) at end of every 2048 byte was corrupted(the values is always FF).

 

Step 1. Flashed kernel image using nandwrite.

  #flash_erase /dev/mtd1 0 0

  #nandwrite -b 1 -n /dev/mtd1 -p /home/uImage

 

Step 2. Flashed u-boot using kobs-ng.

  #flash_erase /dev/mtd0 0 0

  #kobs-ng init -v --chip_0_device_path=/dev/mtd0 /home/u-boot.bin

 

After Step1 the memory locations(2002 byte, 4050=2002+2048 byte, 6098=4050+2048 byte etc...) are having correct values, but after flashing u-boot with kobs-ng those memory locations(2002 byte, 4050 (2002+2048)byte, 6098(4050+2048) etc...) of kernel partition values are changes to FF.

 

Following is the first memory location corruption example:

Actual value after Step 1:

---------------------------------

# nanddump -c -n -l 1 /dev/mtd2 | grep "000007d0:"

Block size 131072, page size 2048, OOB size 64

Dumping data starting at 0x00000000 and ending at 0x00000001...

0x000007d0: 10 af 40 ee 9a af 07 ee 15 af 07 ee 9a af 07 ee  |..@.............|

#

 

Corrupted value after Step 2:

--------------------------------------

# nanddump -c -n -l 1 /dev/mtd2 | grep "000007d0:"

Block size 131072, page size 2048, OOB size 64

Dumping data starting at 0x00000000 and ending at 0x00000001...

0x000007d0: ff af 40 ee 9a af 07 ee 15 af 07 ee 9a af 07 ee  |..@.............|

#

 

The corrupted value(10 changes to ff) highlighted with bold.

 

My doubht here is why kernel partition value is corrupted while flasing u-boot using kobs-ng. When I flash u-boot also with nandwrite then values are not corrupted.

 

When I flash u-boot first( using kobs-ng) and kernel second then also same issue.

 

Can you guide me to debug the issue while using kobs-ng for flashing u-boot.

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