[LinuxBIOS] More MCP55 hacking

ron minnich rminnich at gmail.com
Tue Dec 12 22:40:17 CET 2006

On 12/12/06, Stefan Reinauer <stepan at coresystems.de> wrote:
> * Lu, Yinghai <yinghai.lu at amd.com> [061212 20:24]:
> > Forget about ACPI for irq routing, They said dsdt is under IBV
> > copyright. I don't think you can prove to implement one dsdt in clean
> > room. (If you can access the system with BIOS, you are contaminated.)
> We need to be very careful here.
> So, since ACPI is also used for bus enumeration these days, am I
> contaminated after running lspci on such a system? I can draw
> conclusions on their bus mapping from that.

There are two lines. There is the line that is real, and the line that
the IBV will want you to think is real. Obviously, since they don't
like the idea of a free bios, they are going to want you to think that
they own everything in ACPI, and that you violate a copyright
everytime you do an lspci. But, ACPI represents real hardware. The
hardware is wired as it is wired .If you learn about how a wire is
connected from ACPI, it is hard for me to see how an IBV can own that

> If I look at their interrupt mapping because my linux kernel prints it
> out with a debug option, am I contaminated then?

I am sure the IBV would love for you to to think so. I don't see how
this is possible.

That said, can we poke at hardware registers etc. to determine what we need?

It's not surprising that ACPI is turning into another form of DRM.
It's a lousy standard, designed to make the world ever safer for the
status quo of proprietary BIOS and OS implementations. I'm not
surprised that the IBV's are now using it as a cudgel.

> How can we _reliably_ find out where the border is here?

who knows ...


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