IMX6UL u-boot read nand data error

[zhaopingyang_sg]

CPU : imx6ul

I'm tring to read data from nand flash,found some data is always fix with 0xFn or 0xnF，show as follows：

The error rule of the data is every two reads. The high quad bit of the 2018 byte in the second read data is fixed as 0xf, and the low quad bit of the 2019 byte is fixed as 0xf.

If two operations read the same page of nand flash, the second read is still wrong.

follows is some log add by myself and nand flash info

How can we solve this problem? 

thanks...

[Sanket_Parekh]

Hi @zhaopingyang_sg 

I hope you are doing well.

Please make sure you have correctly configured nand flash in u-boot.

Please refer to  imx6ul-14x14-evk-gpmi-weim.dts and specify the value of kernel_a env variable in u-boot.

Please try to reproduce this issue in Linux.

Thanks & Regards,

Sanket Parekh

[zhaopingyang_sg]

thanks for your reply.

I have changed the PINMUX  according to dtb. But the problem remains.Then I tested nand read operation in SPL and Linux,all of them works well.

the follows is the data read from nand for each page from 0xfe0 to 0xfe.Could you give me more advices? thanks...

[Sanket_Parekh]

Hi @zhaopingyang_sg 

I hope you are doing well.

Please make sure that the custom uboot configuration contains CONFIG_NAND_MXS=y option.

SPL and U-boot use separate drivers for nand, mxs_nand_spl.c, and mxs_nand.c respectively.

Please provide me with the u-boot version and kernel_a env variable for further debugging.

Thanks & Regards,

Sanket Parekh