From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [RFC PATCH 0/3] ARM: uncompress.h multi-platform enablement Date: Wed, 26 Sep 2012 11:44:22 +0100 Message-ID: <20120926104421.GA7040@n2100.arm.linux.org.uk> References: <1348613212-21897-1-git-send-email-swarren@wwwdotorg.org> <201209261038.36223.arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <201209261038.36223.arnd-r2nGTMty4D4@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann Cc: Stephen Warren , Olof Johansson , Rob Herring , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Stephen Warren List-Id: linux-tegra@vger.kernel.org On Wed, Sep 26, 2012 at 10:38:36AM +0000, Arnd Bergmann wrote: > On Tuesday 25 September 2012, Stephen Warren wrote: > > > > From: Stephen Warren > > > > Tegra's uncompress and debug-macro.S communicate to each-other. Hence, > > we can't be left without uncompress.h in a multi-platform enabled kernel, > > or we'll lose features. This series allows uncompress.h to be used in a > > multi-platform kernel, restores the mvebu uncompress.h, and finally moves > > the Tegra debug macros into the common location. The series as mainly an > > RFC due to the outstanding question of where to put Tegra's > > in the final patch. > > > To follow up on the IRC discussion we had yesterday leading to this patch > set, I had another idea of how to handle the same: Since the decompressor > code is actually fairly separate from the kernel, we could also build > multiple versions of it, and link in the same compressed vmlinux. That rubbishes the idea of a single kernel though, which is to give distros a single kernel image that they can boot on different ARM platforms. They want a single kernel binary that works everywhere, not one which they need to select the right binary to work on platform X. Yes, the _internal_ uncompressed bulk may be the same, but it would require distros to carry around N different kernel images for N different platforms. From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Wed, 26 Sep 2012 11:44:22 +0100 Subject: [RFC PATCH 0/3] ARM: uncompress.h multi-platform enablement In-Reply-To: <201209261038.36223.arnd@arndb.de> References: <1348613212-21897-1-git-send-email-swarren@wwwdotorg.org> <201209261038.36223.arnd@arndb.de> Message-ID: <20120926104421.GA7040@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Sep 26, 2012 at 10:38:36AM +0000, Arnd Bergmann wrote: > On Tuesday 25 September 2012, Stephen Warren wrote: > > > > From: Stephen Warren > > > > Tegra's uncompress and debug-macro.S communicate to each-other. Hence, > > we can't be left without uncompress.h in a multi-platform enabled kernel, > > or we'll lose features. This series allows uncompress.h to be used in a > > multi-platform kernel, restores the mvebu uncompress.h, and finally moves > > the Tegra debug macros into the common location. The series as mainly an > > RFC due to the outstanding question of where to put Tegra's > > in the final patch. > > > To follow up on the IRC discussion we had yesterday leading to this patch > set, I had another idea of how to handle the same: Since the decompressor > code is actually fairly separate from the kernel, we could also build > multiple versions of it, and link in the same compressed vmlinux. That rubbishes the idea of a single kernel though, which is to give distros a single kernel image that they can boot on different ARM platforms. They want a single kernel binary that works everywhere, not one which they need to select the right binary to work on platform X. Yes, the _internal_ uncompressed bulk may be the same, but it would require distros to carry around N different kernel images for N different platforms.