Unable to access complete OCRAM in i.mx8mm

[Jarvis3345]

Hi Team,

Iam currently working on i.mx8mm running linux 5.15 version and u-boot 2022.04, Iam using  OCRAM  to send and receive data from M4 to A53 core as per reference manual i could see that it has an unreserved OCRAM region from 0x00900000 to 0x0091ffff(128kb) and 0x00920000 to 0x0093ffff(128kb).

Iam able to access the complete first sector of OCRAM from 0x00900000 to 0x00910000 region from user space but when i tried to access the region from 0x00920000 to 0x00930000 the kernel crashes.
From u-boot using md command i can see that the second sector is getting initialised.

My questions are:
1.Can i use the complete 256 kb(128*2) of region from the userspace or is it reserved for some resource management service.
2.If i have to use the second sector from user space do i have to make any modifications(dts,driver,atf code),if so please do suggest the solution.

Thank You,
Abiram R

[Bio_TICFSL]

Hello,

The OCRAM is reserved, but you can write on it, if you are sure you don't need the space from OCRAM you can write it

Regards

[Jarvis3345]

Hi,

Can I write to the second sector 0x00920000 to 0x0093ffff?If so currently I am not able to do so, should I have to make any modification?