[OpenBIOS] Intel holding back information
David J. Coffin
dcoffin at shore.net
Sat Aug 7 20:46:07 CEST 1999
You cannot get a DRAM-sizing algorithm from Intel with-
out signing an NDA, and the NDA forbids you to share your
source code without Intel's written permission.
This is necessary to protect Intel's "competitive ad-
vantage", even for a chipset that was discontinued two years
VIA Technologies publishes their DRAM-sizing algorithms
without restriction. The VIA 580VP chipset matches the Intel
430FX almost bit-for-bit, so this is a good place to start.
For an example of actual code, disassemble an Award,
AMI, or Phoenix BIOS. Don't read the BIOS from shadow RAM;
copy it off the chip or find it on the web. The DRAM- and
cache-sizing code are easy to find, because most everything
else is compressed to resemble random noise.
There is no way for the BIOS writer to conceal Intel's
secrets. DRAM-sizing code must run directly off the flash
chip, so it can never be compressed or encrypted.
Dave Coffin 8/7/99
On Fri, Aug 06, 1999 at 01:16:27AM +0200, Niklas Ekström wrote:
> I have been in contact with Intel about obtaining the BIOS specifications
> for various chipsets (in particular the 430FX which is the chipset of my
> testing environment), but they seem very reluctant to give them away. I
> guess it might depend on that a) you normally have to sign a
> Non-Disclosure Agreement to obtain them (which doesn't go well with the
> fact that I will make the source for the BIOS publicly available) and
> possibly b) that I'm a private person and not a well recogized BIOS
> manufacturing company.
> Does anyone have a good suggestion as how to solve this issue? I think
> this is quite a major issue. Even though I think I have a clue on how to
> do most things (detecting memory size and type (FPM/EDO)), I also believe
> there are some things that you would actually need the BIOS specification
> for (atleast so I don't have to _guess_ how to do some things).
> I believe some of you here (professional BIOS programmers) have read these
> specifications. Can you give any hint to how much information these
> specifications contain and how vital that information is? Also, is it
> possible to obtain that information for any other source?
> / Niklas
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