[SLOF] [PATCH slof v5 3/6] fdt: Pass the resulting device tree to QEMU

[Segher Boessenkool]

On Wed, Oct 18, 2017 at 04:15:05PM +0530, Nikunj A Dadhania wrote:
> Segher Boessenkool <segher at kernel.crashing.org> writes:
> > On Wed, Oct 18, 2017 at 08:34:57PM +1100, Alexey Kardashevskiy wrote:
> >> > Or even not define words for the phandle and ihandle if you don't use
> >> > them.  Your choice :-)
> >> 
> >> I need either:
> >> - a variable for the unit address or
> >> - a word to get it ("chosen-cpu-unit").
> >> 
> >> They both are better be defined nearby set-chosen-cpu. But fdt.fs is parsed
> >> before that.
> >
> > Well, set-chosen-cpu shouldn't really decide what the boot cpu is
> > anyway -- it should just set the link in /chosen!
> >
> > The current method of just picking whatever is the first device in /cpus
> > isn't so great anyway.
> 
> Earlier, there was an assumption of /cpus/@0, with addition of cpu
> hotplug in QEMU, I had added code to remove this dependency. That was
> the reason to find the first device in /cpus

Right, but is there any guarantee that will actually be the boot cpu;
maybe on qemu it is, but certainly not elsewhere!  (In practice it will
usually work of course).


Segher