Re: [Qemu-devel] Building QEMU with multiple CPU targets.

[Anthony Liguori <anthony@codemonkey.ws>]

Peter Maydell <peter.maydell@linaro.org> writes:

> On 8 October 2012 07:39, Peter Crosthwaite
> <peter.crosthwaite@petalogix.com> wrote:
>> Im currently investigating the possibility of building QEMU with
>> multiple CPU architectures active concurrently. That is, I have a
>> binary with both an target-arm and target-microblaze and wish to run
>> them as a heterogeneous multiprocessor platform.
>>
>> Given the recent QOM development in making CPUs just another object,
>> shouldn't be possible with a bit of Makefile and configure rework to
>> build qemu-system-arm+microblaze and then create machine models
>> instantiating both CPU types?
>>
>> Are the major complications here from either a Make or QOM perspective?
>
> I certainly think this would be a nice feature to have, but I suspect
> the makefile/QOM bits are probably the easy parts :-)
>
> At the moment things like the translated code cache are basically
> globals and would need to be moved to be per-CPU. Also there are
> still various settings that are compile time which would need to
> become runtime (though we just got rid of the 'size of physical
> address type' one at least).
>
> -- PMM

It may be possible to cheat and compile the TCG + CPU code multiple
times as dynamic libraries.  You can then load the libraries with
dlopen() with local symbol resolution.

Then it's mostly just a build file exercise.

Regards,

Anthony Liguori