Writing to OTP fuse memory via nvmem file

[logman]

Hello,

I would like to program and override the fuse OTP memory on the imx6UL device via the nvmem file (Full path is /sys/bus/nvmem/devices/imx-ocotp0/nvmem)

I can successfully read fuse memory via the nvmem file, and I can read, override and program the fuses using the fuse commands in uboot.

Is it possible to write this memory via the nvmem file?  And is it possible to override the shadow registers using a similar mechanism?  I would like to do this from my application code.

Best Regards,

Tom.

@Dhruvit any ideas please?

[logman]

Thanks @joanxie 

So, this is a valid method to 'prog' the fuse memory from the custom application.  Is there anyway to override the memory instead?  This would be useful during code development, when mistakes are likely.

[joanxie]

Writing fuse through NVMEM is not supported in current LF6.1.1_1.0.0 release, the feature will be officially released in 2023 LF Q3 version, for current bsp, maybe you need change the source code,

maybe you can refer to this

https://community.nxp.com/t5/i-MX-Processors/OCOTP-write-support-on-i-mx8m/m-p/825028

https://community.nxp.com/t5/Security-Blog-NXP-Internal/How-to-fuse-key-through-nvmem/ta-p/1394179

[joanxie]

pls refer to the document as below, the default should be read only, you can change it in the dts file

https://www.digi.com/resources/documentation/digidocs/embedded/dey/3.0/cc6/bsp_r_otp_cc6cc6qp

this is another topic for imx6/7

https://community.nxp.com/t5/Security-Blog-NXP-Internal/Internal-Fuse-programming-error-with-NVMEM-O...