From: Arnd Bergmann <arnd@arndb.de>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Detlef Vollmann <dv@vollmann.ch>,
david@lang.hm,
"Russell King - ARM Linux" <linux@arm.linux.org.uk>,
Nicolas Pitre <nico@fluxnic.net>,
Tony Lindgren <tony@atomide.com>,
Catalin Marinas <catalin.marinas@arm.com>,
lkml <linux-kernel@vger.kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@elte.hu>,
linux-omap@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
David Brown <davidb@codeaurora.org>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [GIT PULL] omap changes for v2.6.39 merge window
Date: Mon, 4 Apr 2011 02:14:16 +0200 [thread overview]
Message-ID: <201104040214.16581.arnd@arndb.de> (raw)
In-Reply-To: <1301869097.2549.36.camel@pasglop>
On Monday 04 April 2011, Benjamin Herrenschmidt wrote:
> On Fri, 2011-04-01 at 16:28 +0200, Detlef Vollmann wrote:
> > > * No board files
> > Where do you put code that needs to run very early (e.g. pinging the
> > watchdog)?
>
> Even on powerpc I keep board files :-)
>
> The main thing is:
>
> - The generic -> board linkage must not be hard (ie, no
> platform_restart, but a board_ops.restart() etc....)
>
> - An average board file is a few hundreds line long, that's it, mostly
> it hooks up to generically provided functions, tho it gets the choice of
> _which_ ones to hookup.
I believe a machine_type is more general than a board file, i.e. what
gets described as a machine in powerpc would often currently correspond
to multiple board files, if I am not mistaken.
The fact that we have a more diverse set of hardware on ARM, and that
it's growing quicker than powerpc also means that we should try harder
to reduce duplication than is necessary there.
> - It can still quirk/fixup a thing or two if needed, I thinkt it's
> useful to keep that around, as long as such "quirks" remain small and
> few. At the end of the day, if dealing with one board special case gives
> you the choice between changing a ton of infrastructure/core to
> introduce a new abstraction to deal with -that- special case vs. having
> a one liner fixup in the platform code, the later is the most sensible
> option. The hard part of course is to have sensible maintainers to make
> sure this doesn't grow back to the old mess.
I guess quirks are fine, as long as it's not required to have a them
for each board. We can have a function that gets called for any matching
"compatible" property of the root node, but I think the default should
be not to need it eventually.
This is one area where I think I can illustrate how a gradual change
from the status quo differs from a parallel new platform implementation:
To gradually change one board file, you would convert the existing
machine description to match the compatible property of the device
tree root node and possibly at a later stage remove that code again
once it's possible to work without it.
When starting out with a fresh implementation, we first need to
change all device drivers that are used on the board to work
without a machine description, but then would not have to change
any code twice, and the work for a similar board is almost done.
Arnd
next prev parent reply other threads:[~2011-04-04 0:15 UTC|newest]
Thread overview: 159+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-17 18:30 [GIT PULL] omap changes for v2.6.39 merge window Tony Lindgren
2011-03-18 2:50 ` Linus Torvalds
2011-03-18 7:06 ` Tony Lindgren
2011-03-18 10:15 ` Russell King - ARM Linux
2011-03-18 11:13 ` Uwe Kleine-König
2011-03-30 17:06 ` Arnd Bergmann
2011-03-30 19:21 ` Linus Torvalds
2011-03-30 20:41 ` Nicolas Pitre
2011-03-30 21:02 ` Linus Torvalds
2011-03-30 23:31 ` Nicolas Pitre
2011-03-30 23:59 ` Russell King - ARM Linux
2011-03-31 0:15 ` Tony Lindgren
2011-03-31 0:31 ` Bill Gatliff
2011-03-31 0:39 ` david
2011-03-31 3:17 ` Nicolas Pitre
2011-03-31 3:29 ` Dave Airlie
2011-03-31 4:38 ` Nicolas Pitre
2011-03-31 9:54 ` Alan Cox
2011-03-31 10:50 ` Russell King - ARM Linux
2011-03-31 12:23 ` Jean-Christophe PLAGNIOL-VILLARD
2011-03-31 12:38 ` Catalin Marinas
2011-03-31 13:01 ` Russell King - ARM Linux
2011-03-31 14:55 ` Bill Gatliff
2011-04-01 12:41 ` Arnd Bergmann
2011-03-31 18:12 ` Sam Ravnborg
2011-03-31 18:17 ` Russell King - ARM Linux
2011-03-31 18:34 ` Jesse Barnes
2011-03-31 13:54 ` Thomas Gleixner
2011-03-31 17:22 ` david
2011-03-31 18:08 ` Koen Kooi
2011-03-31 5:05 ` david
2011-03-31 7:15 ` Nicolas Pitre
2011-03-31 8:06 ` Ingo Molnar
2011-03-31 8:30 ` Russell King - ARM Linux
2011-03-31 10:41 ` Ingo Molnar
2011-03-31 13:25 ` Russell King - ARM Linux
2011-03-31 12:04 ` Thomas Gleixner
2011-03-31 14:43 ` Kevin Hilman
2011-03-31 15:01 ` Thomas Gleixner
2011-03-31 15:05 ` Russell King - ARM Linux
2011-03-31 15:45 ` david
2011-03-31 15:23 ` Arnd Bergmann
2011-03-31 16:58 ` Thomas Gleixner
2011-03-31 18:23 ` Nicolas Pitre
2011-03-31 18:55 ` Thomas Gleixner
2011-04-01 11:32 ` Arnd Bergmann
2011-03-31 20:35 ` Kevin Hilman
2011-04-01 11:29 ` Arnd Bergmann
2011-04-01 7:32 ` Tomi Valkeinen
2011-04-01 11:22 ` Arnd Bergmann
2011-04-01 11:55 ` Tomi Valkeinen
2011-04-01 12:07 ` Arnd Bergmann
2011-04-01 12:15 ` Tomi Valkeinen
2011-03-31 16:03 ` david
2011-03-31 16:45 ` Russell King - ARM Linux
2011-03-31 17:17 ` Linus Torvalds
2011-03-31 19:25 ` Nicolas Pitre
2011-03-31 20:05 ` Linus Torvalds
2011-03-31 20:28 ` Linus Torvalds
2011-03-31 22:49 ` Nicolas Pitre
2011-04-01 0:53 ` Mark Brown
2011-04-01 4:50 ` David Brown
2011-04-01 7:45 ` Ingo Molnar
2011-04-01 13:54 ` Arnd Bergmann
[not found] ` <4D95E112.4020400@vollmann.ch>
2011-04-01 14:59 ` Arnd Bergmann
[not found] ` <4D95EF8E.9080902@vollmann.ch>
2011-04-01 15:50 ` Arnd Bergmann
2011-04-01 17:44 ` Russell King - ARM Linux
2011-04-01 19:54 ` Nicolas Pitre
2011-04-01 21:00 ` Uwe Kleine-König
2011-04-01 22:08 ` Arnd Bergmann
2011-04-02 2:24 ` Nicolas Pitre
2011-04-03 15:26 ` Arnd Bergmann
2011-04-03 16:03 ` Russell King - ARM Linux
2011-04-04 0:59 ` Arnd Bergmann
2011-04-04 8:26 ` Marc Zyngier
2011-04-04 11:03 ` Catalin Marinas
2011-04-04 11:21 ` Russell King - ARM Linux
2011-04-04 13:24 ` Marc Zyngier
2011-04-04 13:31 ` Russell King - ARM Linux
2011-04-04 13:57 ` Marc Zyngier
2011-04-04 20:08 ` Linus Walleij
2011-04-05 6:40 ` Santosh Shilimkar
2011-04-05 7:45 ` Russell King - ARM Linux
2011-04-05 14:15 ` Catalin Marinas
2011-04-05 22:16 ` Linus Walleij
2011-04-06 6:43 ` Santosh Shilimkar
2011-04-05 22:22 ` Linus Walleij
2011-04-06 6:41 ` Santosh Shilimkar
2011-04-05 7:30 ` Marc Zyngier
2011-05-26 13:38 ` Pavel Machek
2011-04-02 2:59 ` Mark Brown
2011-04-04 5:16 ` Jean-Christophe PLAGNIOL-VILLARD
2011-04-04 9:27 ` Nicolas Ferre
2011-04-01 21:10 ` Kevin Hilman
2011-04-01 21:32 ` Arnd Bergmann
2011-04-01 21:51 ` Catalin Marinas
2011-04-03 22:18 ` Benjamin Herrenschmidt
2011-04-04 0:14 ` Arnd Bergmann [this message]
2011-04-04 2:49 ` Nicolas Pitre
2011-04-01 15:27 ` Will Deacon
2011-04-01 15:55 ` Arnd Bergmann
2011-04-01 16:39 ` Linus Torvalds
2011-04-03 22:26 ` Benjamin Herrenschmidt
2011-04-05 23:19 ` Linus Walleij
2011-04-06 8:41 ` Catalin Marinas
2011-04-07 1:44 ` Arnd Bergmann
2011-04-01 20:19 ` Nicolas Pitre
2011-04-02 4:38 ` Richard Cochran
2011-04-02 3:27 ` Mark Brown
2011-04-06 6:11 ` Barry Song
2011-04-06 7:31 ` Bryan Wu
2011-03-31 21:40 ` Thomas Gleixner
2011-03-31 17:56 ` Nicolas Pitre
2011-03-31 18:34 ` Thomas Gleixner
2011-03-31 19:02 ` Linus Torvalds
2011-03-31 8:09 ` Russell King - ARM Linux
2011-03-31 10:49 ` Felipe Balbi
2011-03-31 18:00 ` Alexander Holler
2011-03-31 5:45 ` Geert Uytterhoeven
2011-03-31 7:21 ` Nicolas Pitre
2011-03-30 22:08 ` Tony Lindgren
2011-03-30 21:10 ` Thomas Gleixner
2011-03-30 21:54 ` Tony Lindgren
2011-03-30 22:25 ` Thomas Gleixner
2011-03-30 22:45 ` Tony Lindgren
2011-03-30 22:56 ` Thomas Gleixner
2011-04-01 1:42 ` Mark Brown
2011-03-30 22:38 ` Paul E. McKenney
2011-03-30 22:47 ` Tony Lindgren
2011-03-30 23:13 ` Paul E. McKenney
2011-03-30 23:14 ` Thomas Gleixner
2011-03-30 23:28 ` Tony Lindgren
2011-03-31 11:00 ` Artem Bityutskiy
2011-03-31 13:54 ` Arnd Bergmann
2011-03-30 21:44 ` Tony Lindgren
2011-03-30 22:20 ` Linus Torvalds
2011-03-30 22:39 ` Tony Lindgren
2011-03-31 0:15 ` Russell King - ARM Linux
2011-03-31 0:55 ` Linus Torvalds
2011-03-31 1:15 ` Bill Gatliff
2011-03-31 1:37 ` Linus Torvalds
2011-03-31 1:44 ` Bill Gatliff
2011-03-31 1:56 ` Linus Torvalds
2011-03-31 2:20 ` Bill Gatliff
2011-03-31 3:24 ` Linus Torvalds
2011-03-31 6:42 ` Olof Johansson
2011-03-31 6:56 ` David Brown
2011-03-31 11:27 ` Felipe Balbi
2011-03-31 13:39 ` Thomas Gleixner
2011-03-31 4:09 ` Nicolas Pitre
2011-03-31 10:11 ` Thomas Gleixner
2011-03-30 21:07 ` Russell King - ARM Linux
2011-03-30 22:14 ` Tony Lindgren
2011-04-01 1:17 ` Mark Brown
2011-04-01 14:17 ` Arnd Bergmann
2011-03-18 3:02 ` Linus Torvalds
2011-03-18 7:09 ` Tony Lindgren
2011-03-18 8:06 ` Ohad Ben-Cohen
2011-03-18 23:43 ` Tony Lindgren
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=201104040214.16581.arnd@arndb.de \
--to=arnd@arndb.de \
--cc=benh@kernel.crashing.org \
--cc=catalin.marinas@arm.com \
--cc=david@lang.hm \
--cc=davidb@codeaurora.org \
--cc=dv@vollmann.ch \
--cc=hpa@zytor.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-omap@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=mingo@elte.hu \
--cc=nico@fluxnic.net \
--cc=tglx@linutronix.de \
--cc=tony@atomide.com \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).