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From:   Mathieu Malaterre <malat@debian.org>
Date:   Tue, 24 Apr 2018 20:48:00 +0200
Message-ID: <CA+7wUsyO1QR6wzR9_Lj856m9OKOpvz4OjQKKY8SXe-iG+TbWRg@mail.gmail.com>
Subject: Re: [PATCH] powerpc: Allow selection of CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
To:     Michael Ellerman <mpe@ellerman.id.au>
Cc:     Christophe LEROY <christophe.leroy@c-s.fr>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Wed, Apr 18, 2018 at 5:13 PM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> 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.

Right I see them now.

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

Exactly !

> I assume it doesn't have a serial port.

- 56K Modem line (yes really!)
- 2 USB
- 1 Firewire

:(

> cheers