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Date: Mon, 16 Oct 2017 05:20:59 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: David Gibson <david@gibson.dropbear.id.au>, Thomas Huth <thuth@redhat.com>,
 Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>,
 Greg Kurz <groug@kaod.org>, slof@lists.ozlabs.org,
 Paul Mackerras <paulus@samba.org>, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH kernel] RFC: prom_init: Fetch flatten device tree from the
 system firmware
Message-ID: <20171016102058.GH4406@gate.crashing.org>
References: <20171016054917.21577-1-aik@ozlabs.ru>
 <20171016061125.GD2776@umbus.fritz.box>
 <00ec0e99-45dd-dbe0-d75f-4413253e8093@ozlabs.ru>
 <20171016064633.GE2776@umbus.fritz.box>
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On Mon, Oct 16, 2017 at 06:07:06PM +1100, Alexey Kardashevskiy wrote:
> On 16/10/17 17:46, David Gibson wrote:

> >>>> +		/* Fixup the boot cpuid */
> >>>> +		hdr->boot_cpuid_phys = cpu_to_be32(prom.cpu);
> >>>
> >>> If SLOF is generating a tree it really should get this header field
> >>> right as well.
> >>
> >>
> >> Ah, I did not realize it is just a phandle from /chosen/cpu. Will
> >> fix.
> > 
> > It's not a phandle.  It's just the "address" (i.e. reg value) of the
> > boot cpu.
> 
> Well, it is "reg" of a CPU with phandle==/chosen/cpu so my fdt code needs
> to look there to pick the right "reg" rather than just plain 0. I'll fix
> this but in general can it possibly be not a zero in QEMU/SLOF?

/chosen/cpu is an ihandle, not a phandle.  Most (if not all) references
in /chosen are.


Segher