IMX6UL how to read or write from secure non-volatile storage (SNVS)

[wayneshih]

Hi,

I am currently using YOCTO sumo linux kernel L4.14.98-2.3.1 with imx6ul.

In my application, we need to store our secure data (e.g key) inside secure non-volatile storage (SNVS) region. I don't know how to read/write the SNVS from either linux kernel space or user space.

Is there any example of how to read/write SNVS region?

[haichao]

Hi @wayneshih 

Have you solved your problem? I have the same needs, I also need to store my secure data  inside secure non-volatile storage (SNVS) region，Can you share your experience

Thanks

[igorpadykov]

Hi wayneshih

for secure ram / secure storage examples one can refer to

AN12554 Demo Application to Generate Red/Black Blobs Using CAAM and Encrypt/Decrypt Data

https://www.nxp.com/docs/en/application-note/AN12554.pdf

https://source.codeaurora.org/external/imxsupport/imx_sec_apps/tree/demo-caam-blobs/README.txt

Best regards
igor

[wayneshih]

Thank for your quick reply igor.

The solutions you provide doesn't mention the secure non-volatile storage in imx6ul.

Is it because there is no easy way to access this region or this region is not design for storage security data?

[igorpadykov]

if you are looking for examples for access to snvs registers, one can look at snvs rtc :

https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/rtc/rtc-snvs.c?h=imx_5.4.47_2.2.0

https://source.codeaurora.org/external/imx/imx-test/tree/test/mxc_rtc?h=imx_5.4.47_2.2.0

Best regards
igor