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Message-ID: <42E64B9C.8080202@geodb.org>
Date: Tue, 26 Jul 2005 16:41:32 +0200
From: Andreas Bollhalder <bolle@geodb.org>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] Writing to ROM-Range 0xC800-EFFF
References: <pan.2005.06.06.01.02.06.661201@free.fr>
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To: qemu-devel@nongnu.org

Hello Jim

Thank you for the tips. I will have a look into it. Would be nice if
QEMU could allow us to enable write access to the BIOS memory range
(shadow RAM) which isn't in use.

Andreas

Jim C. Brown wrote:
> On Tue, Jul 19, 2005 at 08:00:21PM +0200, Andreas Bollhalder wrote:
> 
>>Hello
>>
>>What does I need to change in the source code of QEMU that it would be
>>possible to enable write access to the ROM adresses from 0xC800 up to
>>0xEFFF ? For instance, "UMBPCI.SYS"
>>(http://www.uwe-sieber.de/umbpci_e.html) can made this range
>>accessible for direct access if no BIOS-ROM is using it. The original
>>chipset which QEMU emulate (Intel 440FX) does allow this, but in QEMU,
>>it won't work.
>>
>>Any ideas ?
>>
>>Andreas
>>
> 
> 
> I'd recommend looking at i440fx_init() in hw/pci.c as a starting point.
> 
> Also see if you can modify the constant IO_MEM_ROM.
>