[Qemu-devel] Fwd: How to increase ram beyond 756 MB ?

["मनीष शर्मा " <manishs.in@gmail.com>]

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---------- Forwarded message ----------
From: मनीष शर्मा <manishs.in@gmail.com>
Date: 2011/6/14
Subject: Re: [Qemu-devel] How to increase ram beyond 756 MB ?
To: Peter Maydell <peter.maydell@linaro.org>


Thanks Peter.

I am able to change memory size in guest  to 1024 MB now.
After making small change in my kernel file realview_pbx.c.
To changed the address to 0x70000000 instead of 0x80000000
where qemu 0.14.0 is registering the memory.
realview_pbx_fixup () {
....
*-meminfo->bank[2].start = 0x80000000   *
+ meminfo->bank[2].start = 0x70000000
...
}

And to enable *High Memory support* in my kernel.
Now its showing 1024 MB.

Thanks a lot for such a quick reply.

regards,
Manish
2011/6/14 Peter Maydell <peter.maydell@linaro.org>

> 2011/6/14 मनीष शर्मा <manishs.in@gmail.com>:
> > I am using arm on x86, running Linux 2.6.33 as guest and fedora 14 as
> host.
> > And using Realview board inside Qemu Machine.
>
> Do you mean "realview-eb", "realview-eb-mpcore", "realview-pb-a9",
> or "realview-pbx-a9" ? They are different models.
>
> > Even though I passed 1024 MB as qemu memory in command line,
> > I can only see ~756MB given to guest. Also I tried passing more than
> > 1024 MB say 2048 MB But I am unable to see increase in RAM in Guest OS.
> > I checked the /proc/meminfo for guest OS memory details.
>
> For both "realview-eb" and "realview-eb-mpcore" the maximum memory
> allowed is 256MB, because the hardware we are modelled has an
> address space layout which does not permit more. If you're using
> those models, then to use more RAM you must use a different model.
>
> "realview-pb-a9" and "realview-pbx-a9" should both in theory
> support 1024MB of RAM as a maximum. Typically to make this work
> you need to both pass QEMU the "-m 1024" option (to model the
> extra RAM) and also pass the guest kernel an option like "mem=1024M".
> (However the pb-a9 hardware has 512MB of RAM as a maximum and
> we are providing extra modelled RAM in a "reserved" section of
> the address space, so it's possible the guest kernel wouldn't
> try to use it.)
>
> -- PMM
>



-- 
-मनीष



-- 
-मनीष

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