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Date: Sun, 30 Mar 2008 13:07:03 -0400
From: Kevin O'Connor <kevin@koconnor.net>
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Subject: [Qemu-devel] Re: [Bochs-developers] [PATCH] BIOS delay_ms optimized
	away with?BX_QEMU enabled
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To: Volker Ruppert <info@vruppert.de>
Cc: bochs-developers@lists.sourceforge.net, David Wentzlaff <wentzlaf@cag.csail.mit.edu>, qemu-devel@nongnu.org

On Sun, Mar 30, 2008 at 06:48:29PM +0200, Volker Ruppert wrote:
> > Do you know why QEMU uses different code for the delay?  What's wrong
> > with using inb(0x61) for both bochs and qemu?
> 
> Bochs really supports the refresh toggle bit of port 0x61, but Qemu toggles on 
> every read access. I have created a patch for Qemu that implements the 15 
> usec toggle, but the Qemu developers haven't accepted it. They are not sure 
> whether the refresh toggle bit exists on modern hardware.

Ughh.  The same delay mechanism is used in the int/15/86 handler even
on qemu.  See rombios.c:int15_function32().

Is there a better way to implement a usleep function?

Thanks for the info.
-Kevin