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Date: Mon, 09 Nov 2009 22:25:34 +0100
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To: Blue Swirl <blauwirbel@gmail.com>
Cc: Avi Kivity <avi@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

On 11/09/09 21:38, Blue Swirl wrote:
>> As Michael notes, devices have physical address sizes independent of the
>> target platform; a PCI device that supports 64-bit addresses can be plugged
>> into a motherboard that supports 32-bit address bus processors.
>
> True. But I think the solution is not to make all buses maximum width,
> but support multiple buses with width translation in between.

I suspect translating between 32 and 64 bit is more complex and more 
overhead than simply using 64bit all the time.

> We could improve the compilation system so that on 64 bit hosts the
> benefit of single size target_phys_addr_t results in compiling the
> files only once.

I think this is already the case.  When building on x86_64 host (both 
32bit and 64bit targets) I find the libhw32 directory empty ...

cheers,
   Gerd