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From: arnd@arndb•de (Arnd Bergmann)
To: linux-arm-kernel@lists•infradead.org
Subject: Building for MMU-less vexpress targets
Date: Mon, 5 Nov 2012 19:08:34 +0000	[thread overview]
Message-ID: <201211051908.34291.arnd@arndb.de> (raw)
In-Reply-To: <20121105173640.GR3351@mudshark.cambridge.arm.com>

On Monday 05 November 2012, Will Deacon wrote:
> I was playing around with !CONFIG_MMU today and to my dismay noticed that
> you can't select ARCH_VEXPRESS without CONFIG_MMU=y! This is because
> ARCH_VEXPRESS is only selectable via ARCH_MULTI_V7, which depends on
> ARCH_MULTIPLATFORM which in turn depends on MMU.
> 
> I'm inclined to add a dummy VEXPRESS entry to arm/Kconfig which depends on
> !ARCH_MULTIPLATFORM and just selects ARCH_VEXPRESS (with the if ARCH_MULTI_V7
> dependency dropped) but I wondered if you'd got any better ideas?
> 

I don't actually remember what the reason for making ARCH_MULTIPLATFORM
depend on MMU was. Maybe it just works if you drop the dependency.

Presumably it's related to ARM_PATCH_PHYS_VIRT and AUTO_ZRELADDR not
working on NOMMU, but if that's the case, we could make it


ARCH_MULTIPLATFORM
	bool "Allow multiple platforms to be selected"
	select ARM_PATCH_PHYS_VIRT if !MMU
	select AUTO_ZRELADDR if !MMU

but maybe those actually work without MMU as well. I have never looked too
closely at NOMMU configurations, every time I tried, they were broken in
combination with something else I wanted to enable.

	Arnd

  parent reply	other threads:[~2012-11-05 19:08 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-05 17:36 Building for MMU-less vexpress targets Will Deacon
2012-11-05 18:03 ` Pawel Moll
2012-11-05 18:13   ` Will Deacon
2012-11-05 19:08 ` Arnd Bergmann [this message]
2012-11-06 12:20   ` Will Deacon
2012-11-06 17:33     ` Arnd Bergmann
2012-11-06 18:34       ` Will Deacon
2012-11-06 20:35         ` Arnd Bergmann
2012-11-06 20:58       ` Nicolas Pitre
2012-11-06 21:14         ` Arnd Bergmann
2012-11-06 22:14           ` Russell King - ARM Linux
2012-11-06 22:59             ` Rob Herring
2012-11-07 12:59             ` Arnd Bergmann
2012-11-07 13:39               ` Russell King - ARM Linux
2012-11-06 23:14           ` Nicolas Pitre
2012-11-07 10:21             ` Will Deacon
2012-11-07 13:29             ` Arnd Bergmann
2013-01-08 19:01             ` Jonathan Austin
2013-01-08 19:11               ` Arnd Bergmann
2013-01-08 19:22                 ` Nicolas Pitre
2012-11-06 22:51         ` Jamie Lokier
2012-11-06 23:40           ` Nicolas Pitre
2012-11-06 23:46             ` Jamie Lokier

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