DM816x EVM NAND ECC problem

Hyunho Youn

Intellectual 260 points

Hi,

I'm using EZSDK 5_02_01_59 at DM816x EVM.

I have written some data to NAND flash at u-boot, after linux booting I read the data.

Following messages is occured.

Error: Bad compare! failed
Error: Bad compare! failed

So, I check NAND OOB area.

When I write some data to nand at uboot, the OOB is like as following,

OOB:
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        56 56 ff 9c 9c 44 77 88
        1e 00 00 00 ff ff ff ff
        ff ff ff ff ff ff ff ff

And I write some data to nand after linux booting, the OOB is

OOB:
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff
        ff ff ff ff 04 04 00 fb
        04 07 fd 02 07 00 00 00

ECC position is different and ECC valus is simpler.

In my thought, the MTD of EZSDK linux kernel may have some problem.

Is there anyon to help me?

over 14 years ago

0 Parth Saxena over 14 years ago

TI__Intellectual 1265 points

Youn,

Yes, the ECC schemes to write in Uboot and Kernel were different and we have verified that ourselves also. We have created a patch to resolve this and the patch is under validation.

However, using this release, we have tested that when a FS image is flashed from Uboot or Kernel, it can be read by the kernel in both cases. After the above patch is applied, flashing from kernel and then reading in Uboot will also be possible.

Regrads,

Parth

0 Hyunho Youn over 14 years ago in reply to Parth Saxena

Intellectual 260 points

Dear Parth Saxena,

Thanks for your reply.

What is the "FS images", you mentioned ?

And, when I get the patch ?

Regards,

0 Parth Saxena over 14 years ago in reply to Hyunho Youn

TI__Intellectual 1265 points

Hyunho,

'FS images' stands for File System images.

The patch will be integrated in our next release. You won't observe similar issue then.

Regards,

Parth

0 Tomokazu Miyazaki over 14 years ago in reply to Parth Saxena

Intellectual 270 points

Hello.

Now, I have encountered this NAND issue.

Is this issue cleared by EZ SDK 5.03?

Which of uboot and Kernel did you revise?

Regards,

-Miyazaki

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DM816x EVM NAND ECC problem