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From: Michael Ellerman <mpe@ellerman.id.au>
To: Mathieu Malaterre <malat@debian.org>,
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Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
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Subject: Re: [PATCH] powerpc: Allow selection of
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Date: Thu, 19 Apr 2018 01:13:18 +1000
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Mathieu Malaterre <malat@debian.org> writes:
> On Wed, Apr 18, 2018 at 8:34 AM, Christophe LEROY
...
>
>> Can you also provide a copy of the messages you can see (prom_init ...) when
>> boot is ok ?
>
> Hum. I've always been interested in seeing it also myself. Is there a
> way to setup env to see those message (netconsole, delayed boot
> messages ...) ? I never found a clear documentation on how to do that
> on (closed) Apple hardware.

If you see nothing after prom_init it usually indicates the kernel died
very early in boot before it could find the console.

The only option then is to enable one of the hard-coded EARLY_DEBUG
options.

I don't know which one works on a G4, maybe CONFIG_PPC_EARLY_DEBUG_BOOTX ?

I assume it doesn't have a serial port.

cheers