From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] Re: QEMU-KVM and video performance
Date: Wed, 21 Apr 2010 19:39:31 +0100
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References: <alpine.LFD.2.00.1004192101000.10357@bbs.intern> <4BCEBE5C.4020404@redhat.com> <20100421100840.GF13114@shareable.org> <4BCED82C.9020702@redhat.com>
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Cc: Gerhard Wiesinger <lists@wiesinger.com>, qemu-devel@nongnu.org,
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To: Avi Kivity <avi@redhat.com>
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Avi Kivity wrote:
> Writes to vga in 16-color mode don't change set a memory location to a 
> value, instead they change multiple memory locations.

While code is just writing to the VGA memory, not reading(*) and not
touching the VGA I/O register that control the write latches, is it
possible in principle to swizzle the format around in memory to make
regular writes work?

(*) Reading should be ok for some settings of the write latches, I
think.

I wonder if guests of interest behave like that.

> >Is this a case where TCG would run significantly faster for code blocks
> >that have been detected to access the VGA memory?
> 
> Yes.

$ date
Wed Apr 21 19:37:38 2015
$ modprobe ktcg
;-)

-- Jamie