[RFC] powerpc: Document new property called interrupt-parents
segher at kernel.crashing.org
Thu Mar 1 05:54:31 EST 2007
>> Well, whatever Segher says, I'm still very concerned about the
>> potential for extra difficulty in debugging with this approach.
> The issue, as I understand it, is the potential for an old
> kernel parser to silently misparse a new dev tree with this
> new property.
Exactly. Note that such such an old parser will misparse
the "interrupt-array" property as well, namely, not at all.
Debugging *could* be a bit easier though, who knows.
> Do the version and last_comp_version in the blob header
> help here?
That's not what those version fields are for.
The real solution is to just not use too old kernels with
too new a firmware/bootloader/device tree. This issue
has existed for since forever and is in no way specific
to adding new OF bindings, or specific to Linux, or
anything like that.
> It's more of a general problem.
It might be worthwhile to add a device tree property
"minimum-linux-version" (in the tree root) that the kernel
will parse and complain about loudly if it doesn't match;
at a minimum it will make it super-duper clear to users
of a DTS with that property which combos work. Documentation
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