Hi Russell
Thanks for the reply. I guess I'll be doing a lot of trial and error unless
I go the whole hog and do x86 emulation too. The only problem there is that
I'll have to port it to Java, a non-trivial task. Which emulator are you
using?
Also, have you made any attempt to look at the BIOS disassembly in order to
copy the initialization code? I thought I might take that route.
Thanks again for responding.
Roland
p.s. I posted to the list too just in case anyone else is interested
-----Original Message-----
From: Russell King - ARM Linux Admin <[EMAIL PROTECTED]>
To: Roland Paterson-Jones <[EMAIL PROTECTED]>
Cc: [EMAIL PROTECTED] <[EMAIL PROTECTED]>
Date: 28 September 2000 17:35
Subject: Re: Video Cards
>Roland Paterson-Jones writes:
>> I notice that there is some mention of an S3 card in the diary, but what
>> scares me is the mention that an x86 emulator had been compiled into the
>> image to get it working. What was wrong with manual initialization?
>
>I used to do my own initialisation, but there were problems with doing
>this. Some of the settings had to be guessed and trialed, and it was
>never perfect. By this, I mean I had white text on grey background.
>In addition, dispite there being links on the card to tell the chip
>what type of video memory the board contained, these links were set
>wrong, so the only accurate source of this information was presumably
>buried in the BIOS.
>
>The PCI standard allows two different types of ROM format - one is based
>on Forth, the other is x86 machine code. Unfortunately, most cards
>contain x86 machine code.
>
>Therefore, the only reliable way to initialise such cards is to actually
>run the BIOS, which, in this case is the x86 code.
>
>The only other way is to be limited to just one video card with one
>fixed initialisation method. In an industry where things go obsolete
>very quickly, this IMHO is not a good answer.
>
>Therefore, I took the decision to include an x86 emulator core into the
>EBSA285 BIOS so that most video cards could and should work.
>
>Currently, the emulator is not all that fast, mainly because its running
>in the BIOS without the D-cache and writebuffers on. However, I am
>considering turning these on for better performance.
> _____
> |_____| ------------------------------------------------- ---+---+-
> | | Russell King [EMAIL PROTECTED] --- ---
> | | | | http://www.arm.linux.org.uk/ / / |
> | +-+-+ --- -+-
> / | THE developer of ARM Linux |+| /|\
> / | | | --- |
> +-+-+ ------------------------------------------------- /\\\ |
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