[coreboot] .cb files

Eric W. Biederman ebiederm at xmission.com
Sat Jan 8 11:25:48 CET 2011

Peter Stuge <peter at stuge.se> writes:

> Of course not, that would be redundant. As Kerry pointed out, they
> are very much part of the build process. You can also see this very
> clearly when watching the make output.
>> #device pci 1e.2 off end # AC'97 Audio
>> It means that AC'97 Audio is on Bus#=1 and Function#=2?
> I don't know about the bus number because you took the above line out
> of context, but device 0x1e function 2 yes.
>> But all the devices of the south bridge, ICH7 are on Bus number 0,
>> as far as I know.
>> Why you have not written, Bus number, Function number, Device number,
>> Register number clearly.
> Because it is not a list of registers. Device and function is there
> and bus is implicit, but the file encodes more complex knowledge
> about the board than simply a list of register/value pairs.

> The bus number is implicit because the file is structured rather than
> a simple list. The indentation and the "end" keywords try to make
> this obvious.

Bus numbers should be a deliberately not specified because in general
we need to wait until all of the devices are present both static and
dynamic before we can reasonably assign bus numbers.  There might
be a plugin card with a pci-pci bridge that changes our bus numbering


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