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Date: Wed, 2 Jan 2008 20:17:42 +0200
From: "Blue Swirl" <blauwirbel@gmail.com>
Subject: Re: [Qemu-devel] Re: [RFC] 64 bit i/o
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To: qemu-devel@nongnu.org

On 1/2/08, Brian Johnson <bjj4@charter.net> wrote:
> Robert Reif wrote:
> > Paul Brook wrote:
> >>
> >> Couldn't you just latch the value when one half is accessed?
> >>
> > In this one specific case you could do that but this is not the only
> > case in sparc32 (TOD, MXCC, ...) and other architectures with 64 bit
> > hardware have similar requirements.
> >
> > This is a generic solution that fills a hole in the qemu
> > implementation.
>
> Agreed.  Some non-PC hardware has 64-bit registers which need to be
> accessed as 64-bit quantities, in order to read or write all fields at
> once.  Qemu should support 64-bit I/O.

On Sparc64 many registers can only be handled using 64 bit accesses,
other methods should raise an exception.