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IMX53 - NAND - Kernel 4.4.xx - ONE BYTE OFFSET IN READS

Question asked by Noel Vellemans on Jul 12, 2017
Latest reply on Jul 14, 2017 by Noel Vellemans

Hi All

 

We have been running 2.6.35.x for some time now on our IMX53 custom boards ( booting from nand)

 

Recently we started in UPGRADING the kernel to a more recent version ( 4.4.75 currently).

Al fine so far.

 

In the lab I'm using different boards ( +10 pieces)  to test drive the new kernel.

9 out of the 10 boards are running fine with this new KERNEL , 1 board is failing to recognize the NAND-FLASH ( 8 bits , 2 chips , hardware ECC enabled, Micron MT29F16G08ABACAWP) with this NEW kernel ( with the old kernel all seems to be fine...)

 

 

The reason for this failure is that when trying to read the ONFI-Parameter PAGE, there seems to be a one BYTE offset into the bytes READ from the NAND-CHIP ( command NAND_CMD_PARAM)

 

For 9 of the 10 boards... the data read back STARTS ( as specified ) with ONFI.

 

For the failing CPU/BOARD board is starts with NFI ( O is missing) ( all 256 bytes are shifted one byte , or otherwise said, the FIRST byte is missing ... ( if the First Byte would be there all would be OK.. so it is no rubbish.. ))

 

Reading Manufacturer ID: 0x2c, Chip ID: 0x48 , is working... reading ONFI PARAMETER PAGE... is failing ! ( with the 4.4.x-kernel) 

 

I do have swapped the FLASHES  and the ERROR stays with the CPU/BOARD.

 

{ Note putting the OLD kernel back ... 2.6.35.x .. and all is working fine.. must be related to NEW-kernel drivers , but could be a silicon bug triggered by some exception if you ask me .. been digging for more than a week on this}

 

I've been cross checking ERATA's but can not find anything that would fit.

I've been triple checking each NFC register as well .. all registers are setup correctly  ( comparing good/ bad board.=> same register settings)  !

 

 

Any clue ? any hints .. to get me  going  ( as said before,  i've been searching for one week on this.. no luck so far, in understanding / solving the issue .. ! )

 

Just for info, type of NAND used ( 2 chips , 8 bit mode) :

nand: device found, Manufacturer ID: 0x2c, Chip ID: 0x48
nand: Micron MT29F16G08ABACAWP
nand: 2048 MiB, SLC, erase size: 512 KiB, page size: 4096, OOB size: 224

 

 

 

 

Best Regards

Noel

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