From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Andrew F. Davis" <afd@ti.com>
Date: Sun, 25 Oct 2015 19:45:54 +0000
Subject: Re: [GIT PULL] On-demand device probing
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To: Tim Bird <tim.bird@sonymobile.com>, "frowand.list@gmail.com" <frowand.list@gmail.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>, Rob Herring <robh+dt@kernel.org>, Mark Brown <broonie@kernel.org>, Russell King <linux@arm.linux.org.uk>, Michael Turquette <mturquette@baylibre.com>, Stephen Boyd <sboyd@codeaurora.org>, Vinod Koul <vinod.koul@intel.com>, Dan Williams <dan.j.williams@intel.com>, Linus Walleij <linus.walleij@linaro.org>, Alexandre Courbot <gnurou@gmail.com>, Thierry Reding <thierry.reding@gmail.com>, David Airlie <airlied@linux.ie>, =?UTF-8?Q?Terje_Bergstr=c3=b6m?= <tbergstrom@nvidia.com>, Stephen Warren <swarren@wwwdotorg.org>, Wolfram Sang <wsa@the-dreams.de>, Grant Likely <grant.likely@linaro.org>, Kishon Vijay Abraham I <kishon@ti.com>, Sebastian Reichel <sre@kernel.org>, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>, David Woodhouse <dwmw2@infradead.org>, Liam Girdwood <lgirdwood@gmail.com>, Felipe Balbi <balbi@ti.com>, Jingoo

On 10/23/2015 10:45 AM, Tim Bird wrote:
> I've been worried about DT overhead adding to boot time for a while.
> And IMHO probe deferral is just about the lamest way to solve boot
> order dependencies I can imagine, from a computer science perspective.
> (Well, there's a certain elegance to it, but it's a stupid "make
> everything re-doable, back up and start over, time-wasting" elegance.)
>

It has a bogosort kind of elegance. :)

Also this might be a silly question (I haven't been following this issue
for very long), but as the only place that can really know what devices
depend on each other, in a generic kernel, is the DT (or whatever
abstraction) will we not eventually need to solve this issue there? Could
we just add a "depends-on = <&phandle>;" to nodes when we know they are
needed for our board?