[Arm-netbook] Mele A1000 defective memory and related

[Valery Yundin]

Hello,

I've found that my Mele A1000 box has defective memory. The testing with
memtester program revealed (after remapping to physical range) that there
is a bunch of unstable addresses of this form 0x54XXX3A4, which corresponds
to 16M after first 320M of RAM.

I've tested both in Ubuntu and in stock Android (with statically
linked memtester).
The picture is the same, so kernel and driver issues are probably ruled out.

So far I've fixed it by excluding offending region in kernel command line.
Unfortunately memmap option does not work on arm, but one can just specify
disjoint memory regions as separate mem commands (kernel will merge them)
mem=320M at 0x40000000 mem=112M at 0x55000000 console=ttyS0,115200
At first glance it seems to fix the issue.

I wonder if anyone had similar problems. Also I've spotted a few DRAM
related options in script.fex[bin], does anybody know what they mean? Can I
reduce ram clocking or increase latencies to make it more stable? Is there
any chance it would it help or it is just defective chip?

Another related question. Why we use only the first 448M out of 512?
Is it reserved for GPU? Would it be possible to utilize it if I'm running
a headless box and do not need graphics?

PS sorry if this message appears twice.

With best regards, Valery Yundin.