imx25 booting from a NAND flash using internal boot(MT29F8G08ADBDAH4)

[chandansingh]

Hi All,

We have designed and built our custom board which has micron NAND flash(MT29F8G08ADBDAH4).

Able to download u.boot on the board in UART/USB dowload mode (bootmode=11) and checked back by enabling "Read Back check" flag.

but tried to boot from internal NAND boot(boot mode == 00) and it doesn't work.

Verified the BT_ pins used to configure all the boot parameters and they seems to be ok

After reset i can see "read enable(RE)" signal on the nand and i see some access on the nand bus for some time and it seems to be the first 4K read but nothing more.

If  i look at the signal on the Evalboard(iMX257-3pdk) i see a very long read access : of course the rom boot read the uboot total size image.

Now i have no idea what to look for.

Is there any way through which we can check that processor has gone in uart/usb boot again after encountering failure during processing of first 4kb NAND Flash?

How to read the errors logged by bootROM?

Thanks & Regards,

Chandan

[JorgeRama_rezRi · Accepted solution]

Hi Chandan,

That sounds similar to a problem I had a couple of years ago. The issue was in the timing between the RB signal toggle and the first RESET command. If it was too long (in my case, more than 460us), the processor wasn't able to boot. Do you have a board that boots so you can compare this timing?

And another possible cause: Have you already addes SW support to the BSP for the NAND you are using?

Best regards.

Jorge.