Message-Id: <m10CRaX-000S61C@inti.gov.ar>
Comments: Authenticated sender is <salvador AT natacha DOT inti DOT gov DOT ar>
From: "Salvador Eduardo Tropea (SET)" <salvador AT inti DOT gov DOT ar>
Organization: INTI
To: Shawn Hargreaves <ShawnH AT Probe DOT co DOT uk>, djgpp AT delorie DOT com
Date: Mon, 15 Feb 1999 14:16:53 +0000
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Subject: Re: Line frame buffer speed problem
In-reply-to: <8D53104ECD0CD211AF4000A0C9D60AE3538051@probe-2.acclaim-euro.net>
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Reply-To: djgpp AT delorie DOT com

Shawn Hargreaves <ShawnH AT Probe DOT co DOT uk> wrote:

> Ludvig Larsson writes:
> > The testvalues from SciTech Display Control Center:
> >
> > mode: 640x480x16bit: Banked
> >
> > Clr screen: 75Mb/sec
> > BitBlt:     55Mb/sec
> > 
> > mode: 640x480x16bit: Linear buffer
> >
> > Clr screen: 21Mb/sec
> > BitBlt:     19Mb/sec
> 
> That is _really_ weird. Sorry, I don't have anything especially useful
> to suggest here other than to say that I've never heard of anything
> like this before :-) I would have put money on these results being
> due to something odd in your code rather than the video hardware,
> but that doesn't make sense when you see the poor performance in the
> SciTech test program as well as with your code, and when using a
> totally different VESA driver...

I saw this before in a TGUI9440 board. The Ivan Baldo board+motherboard 
combination makes the LFB slower than the banked mode. Looks like the problem 
is above/below 1Mb. That's why I'm blitting the accelerated things in the 
0xA0000 address instead of the LFB, it have the same performance in my 
motherboard, but is much faster in Ivan's computer.

SET

P.S. In the TGUI9440 only the first 32 bits of the memory are really used 
when blitting things that will be finally placed in the right 
place by the accelerator.
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