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From: Brian Johnson <bjj4@charter.net>
Date: Wed, 02 Jan 2008 09:28:49 -0600
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Subject: [Qemu-devel] Re: [RFC] 64 bit i/o
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To: qemu-devel@nongnu.org

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.

Brian