From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Fri, 6 Sep 2013 12:12:45 +0200 Subject: [Buildroot] [PATCH 2/2] arch/Config.in: Allow ARM to select BR2_BINFMT_FLAT In-Reply-To: <5229A990.7080906@zacarias.com.ar> References: <1378262598.32360.5.camel@phoenix> <1378262667.32360.6.camel@phoenix> <20130905234841.3bbfe0d4@skate> <20130906082537.08818fba@skate> <5229A990.7080906@zacarias.com.ar> Message-ID: <20130906121245.565c2208@skate> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Dear Gustavo Zacarias, On Fri, 06 Sep 2013 07:08:16 -0300, Gustavo Zacarias wrote: > On 09/06/2013 03:25 AM, Thomas Petazzoni wrote: > > > On Fri, 6 Sep 2013 03:08:10 +0200, Thomas De Schampheleire wrote: > > > >> Don't we/shouldn't we have something like ARCH_HAS_MMU and/or > >> ARCH_SUPPORTS_FLAT_BINARY? > > > > Yes, we should probably have something like this (and ditto for other > > binary formats: ELF, FDPIC and so on). > > On a side note, remember that HAS_MMU doesn't mean it's using it - from > what i've read you can use MMU-bearing processors to test uclinux > MMU-less scenarios (dunno if it can be done with every SOC out there, > probably depends on the linux support for each one, at least a couple of > Atmel ones were used this way for testing and/or masochism). Right. We could distinguish what the hardware is capable of (i.e BR2_HAS_MMU vs. !BR2_HAS_MMU) and what the user wants to do (BR2_USE_MMU vs. !BR2_USE_MMU). Of course, BR2_USE_MMU depends on BR2_HAS_MMU. That said, until now, we've been hiding BR2_USE_MMU on many architectures for which !MMU doesn't exist/isn't supported. On ARM, I believe it doesn't make much sense to expose !MMU for MMU-capable variants. Best regards, Thomas -- Thomas Petazzoni, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com