But I actually think that is overkill. v2 by default and design enables all of the shadow ranges as memory. So we just need to use those ranges. That should be much easier having to patch ADLO each time. It is fairly unlikely a writable ROM segment is going to break anything.
FWIW, I actually do remember someone on the list saying that they had to disable rom write since the things DID break otherwise... anyone else remembers more?
it was in context of ollie's work, not adlo:
Date: Thu, 13 Jan 2005 16:38:47 -0600 From: Richard Smith smithbone@gmail.com To: LinuxBIOS linuxbios@clustermatic.org, YhLu YhLu@tyan.com Subject: Re: Running with VGA
it from normal BIOS, it will skip some operation. In this case, it is probably init font buffer.
I have word from an ATI tech who says they don't do that.
I should clarify this. I thought you guys were talking about zeroing the entry pointer so that if you copied it from ram you would not get a working copy.
Buy yes the ATI bios looks for a bit already set and if so then will skip RAM init and various other things.
My copy checks to see if it can write the into the shadow space before it self-modifies and if not I believe it tries to use some bits in the CMOS. So if you disable writes to your c000 shadow you might trick it to not skip things.