Hello,
what is the reason that linux on the AT91SAM9G45-EKES use only 128MB from the 256MB RAM onboard?

Thanks

The Linux kernel uses only the physical RAM it is told about. This information is passed from the boot program (in this case U-Boot) in the kernel command line (the "mem= " parameter), ATAGS and a list of physical memory regions. The Linux kernel does _not_ perform any main memory sizing or SDRAM initialization; that has to be performed by the boot program(s).

You probably should inspect the U-Boot environment variables for the value of mem that is passed to the kernel.

Regards

hello,
k thanks for the information.

but what is the reason that the shipped linux use only 128MB?
is there any reason?
thx

Please refer to this thread http://comments.gmane.org/gmane.linux.p ... eral/11751 and the patch provided in this thread.

goshik