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Message-ID: <1445474088.30295.5.camel@ellerman.id.au>
Subject: Re: [PATCH v6 22/22] of/platform: Defer probes of registered devices
From: Michael Ellerman <mpe@ellerman.id.au>
To: Scott Wood <scottwood@freescale.com>,
        Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: devicetree@vger.kernel.org, linux-acpi@vger.kernel.org,
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        Mark Brown <broonie@kernel.org>,
        Thierry Reding <thierry.reding@gmail.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        Hu Mingkai-B21284 <Mingkai.Hu@freescale.com>,
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Date: Thu, 22 Oct 2015 11:34:48 +1100
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On Wed, 2015-10-21 at 00:54 -0500, Scott Wood wrote:

> On Mon, 2015-09-21 at 16:03 +0200, Tomeu Vizoso wrote:

> > Instead of trying to match and probe platform and AMBA devices right
> > after each is registered, delay their probes until device_initcall_sync.
> > 
> > This means that devices will start probing once all built-in drivers
> > have registered, and after all platform and AMBA devices from the DT
> > have been registered already.
> > 
> > This allows us to prevent deferred probes by probing dependencies on
> > demand.
> > 
> > Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> > ---
> > 
> > Changes in v4:
> > - Also defer probes of AMBA devices registered from the DT as they can
> >   also request resources.
> > 
> >  drivers/of/platform.c | 11 ++++++++---
> >  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> This breaks arch/powerpc/sysdev/fsl_pci.c.  The PCI bus is an OF platform 
> device, and it must be probed before pcibios_init() which is a 
> subsys_initcall(), or else the PCI bus never gets scanned.

Ah right. This is presumably why I'm not seeing any PCI devices on my p5020ds
with linux-next.

cheers