ARCv2 HSDK : About 4G memory

[charles8299]

Follow below instruction, we only get 1GB DDR after boot into Linux.

RC-Linux-for-HSDK
1G memory

As suggested by SNPS IPK team, after enable PAE support with corresponding DTS modification, we are able to recognize memory beyond 1GB address in linux system.
PAE
DTS

However, the system become unstable since extra 2GB memory is added.
For example, linux sudo command segmentation fault
sudo segmentation fault
vim segmentation fault

executable missing
sudo
Xfce

We can barely run linux system more than 1GB memory.
When switch back to 1GB memory, all system component works fine.
The total 4GB DDR is necessary for our application, thanks for your help.