Re: Question about xserve G5
"Brandon Bergren" <[email protected]>
| Newsgroups | gmane.os.freebsd.devel.ppc |
|---|---|
| Message-ID | <[email protected]> |
In any case, without the interpreter, what we have to do on a per model basis is manually decode the platform functions from a dumped device tree and do the same sequences in C, and then run that code when encountering that model. On Fri, Oct 30, 2020, at 10:25 AM, Brandon Bergren wrote: > > > On Fri, Oct 30, 2020, at 10:02 AM, Javi Hotmail wrote: > > Is there any documentation that I could read about this? Also why is not > > possible from the kernel to run functions from the DT?. I just started > > looking at the code now; It seems to me that depends on some sort of > > openfirmware functionality. Why is this? > > > > Regards, > > > > It's not possible because we don't have an implementation of the > platform function interpreter written. > > If someone were to write a BSD-licensed platform function interpreter, > it would be pretty easy to hook it in. > > The (GPL) linux interpreter is an example of a platform function > interpreter. > https://github.com/torvalds/linux/blob/master/arch/powerpc/platforms/powermac/pfunc_core.c > > Darwin has one as well but when I looked at it it was a bunch of > Objective C that would be less work to just reimplement rather than > trying to use. (I think the license wasn't BSD either) > > The device tree has a series of platform functions that contain > bytecode that the kernel runs to do a function like change the cpu > clockrate, etc. It's done this way so it can be run without having to > context-switch, and have platform drivers that automatically work on > all Mac99 machines. > > I'm not sure off the top of my head what documentation there is available. > _______________________________________________ > [email protected] mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-ppc > To unsubscribe, send any mail to "[email protected]" > -- Brandon Bergren [email protected] _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-ppc To unsubscribe, send any mail to "[email protected]"