How to fix RAM size limit 256MB on realview-pbxa9 platform.

Adam Lackorzynski adam at
Sat Dec 24 10:29:43 CET 2011


On Thu Dec 22, 2011 at 14:40:42 +0300, e.fedotov wrote:
> This post is about how to eliminate memory restriction 256MB in
> realview-pbxa9 platform (ARM Cortex A9 processor). The problem is
> that L4 bootstrap doesn't scan all RAM memory presented on this
> board. In QEMU source code for this platform (see hw/realview.c in
> QEMU source directory, function: realview_init) we can find that it
> can be 3 memory intervals in pbx a9:

The first 512MB are at 0x70000000, at 0 there's just an alias of the
first 256MB of that memory. So what can be done is this in the build-dir:
$ make switch_ram_base RAM_BASE=0x70000000
Which will change the ram-base to 0x70000000 and make 512MB available.

Adam                 adam at

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