imx6 boot fail for OTP - imxotp and HW_OCOTP_CFG

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

imx6 boot fail for OTP - imxotp and HW_OCOTP_CFG

1,588 Views
TracyZhang
Contributor I

         Please help me to save the main board.
The main boards I use are imx6q, kernel 3.0.35, Android 4.4.2
I use the fuse mechanism to prepare for the production of the factory.
echo 0x00005860 >/sys/fsl_otp/HW_OCOTP_CFG4
echo 0x00000010 >/sys/fsl_otp/HW_OCOTP_CFG5
Then it is true that the device can be used.
         But I accidentally operated on the following statement:
echo 0x0000787B >/sys/fsl_otp/HW_OCOTP_CFG4
Then it operates again.
echo 0x00005860 >/sys/fsl_otp/HW_OCOTP_CFG4
cat /sys/fsl_otp/HW_OCOTP_CFG4
The result is 0x0000787B, not 0x00005860.
Then the system can't start.
          I used mfgtool to burn a uboot that was started from memory, modified the command imxotp, forced to write to 0x00005860, and used the command operation as follows:
         MX6Q SABRESD U-Boot >imxotp blow --force 5 0x5860
Current fuse at (index: 0x5) value: 0x787B
Blowing fuse at index: 0x5, value: 0x5860
Reloading shadow registers...
Operation succeeded fuse at (index: 0x5) value: 0x787B
But it still doesn't become 0x00005860.
         MX6Q SABRESD U-Boot >imxotp read 0x5
Reading fuse at index: 0x5
Fuse at (index: 0x5) value: 0x787B

        Or enter the system, as follows:

echo 0x00005860 >/sys/fsl_otp/HW_OCOTP_CFG4

The result is 0x0000787B, not 0x00005860.

         I can't help me. Please help me.

How to remove its value or write to 0x5860.

What's the matter with this situation?

       Online wait!

       Help, thank you!

0 Kudos
2 Replies

875 Views
igorpadykov
NXP Employee
NXP Employee

Hi tracy

if board is developed to boot from fuse, I am afraid there is no way to recover

it if fuses are incorrectly blown. Seems only option is to use it with jtag debugger or

load images through usb, using mfg tool or usb loader:

GitHub - boundarydevices/imx_usb_loader: USB & UART loader for i.MX5/6/7 series 

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

0 Kudos

875 Views
TracyZhang
Contributor I

Hi igor,

         It looks like it's not saved. It's too dangerous to use fuse.
         Does imx6 leave behind some back doors to solve similar problems?
         Should it be possible to solve the problem if the CPU is replaced?

         Thank you very much! Look forward to your reply!

0 Kudos