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Date: Wed, 02 Jan 2008 09:54:35 -0500
From: Robert Reif <reif@earthlink.net>
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Subject: Re: [Qemu-devel] [RFC] 64 bit i/o
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	<200801021401.13611.paul@codesourcery.com>
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To: qemu-devel@nongnu.org

Paul Brook wrote:

>On Wednesday 02 January 2008, Robert Reif wrote:
>  
>
>>Sparc32 has a 64 bit counter that should be read and written as 64
>>bits but that isn't supported in QEMU.  I did a quick hack to add
>>64 bit i/o and converted sparc32 to use it and it seems to work.
>>I'm suppling the sparc changes to get comments on if this is worth
>>pursuing.
>>    
>>
>
>Couldn't you just latch the value when one half is accessed?
>
>Paul
>
>
>
>  
>
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.