[Fwd: Re: Linuxbios and Linspire laptop]

Stefan Reinauer stepan at openbios.org
Wed Jun 2 03:32:00 CEST 2004


* ron minnich <rminnich at lanl.gov> [040601 22:50]:
> word from someone who knows that acpi tables have many errors. Windows 
> drivers work around the bugs in acpi tables. Linux follows the spec 
> closely, hence the problems people see with linux+acpi. 

Ron, 

you are perfectly right with the fact that ACPI tables are very often
buggy. But this strengthens the case against (some) commercial bios writers
rather than against ACPI as a concept. Still it is a sound argument that
the complexity of something that could be really simple drives bios
writers to include these bugs.

Yet, there's often the case of ACPI tables working around bugs in
Windows' ACPI implementation which can cause problems on Linux. Another
one of the most stupid things I've ever seen is that ACPI can have
different code paths for different OSes.  Thus, of course ACPI writers
go the usual way: "Works with Windows, we can ship it." I have seen
quite a couple boards that were able to cope fine with Linux ACPI after
Linux has been told to pass the Windows ID string to the ACPI code.

One thing that is generally good about ACPI (well in some sense) is that
it is free of callbacks, which I often hear as a disadvantage of Open
Firmware's interface. (While dropping callbacks in OF is just a matter
of directly providing the FCode drivers to the OS and let a hosted Open 
Source OF implementation use it there)

Stefan




More information about the coreboot mailing list