From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tim Bird Subject: Re: [RFC PATCH 0/3] ARM: uncompress.h multi-platform enablement Date: Wed, 26 Sep 2012 06:48:16 -0700 Message-ID: <506307A0.7010701@am.sony.com> References: <1348613212-21897-1-git-send-email-swarren@wwwdotorg.org> <201209261038.36223.arnd@arndb.de> <20120926104421.GA7040@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120926104421.GA7040-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Russell King - ARM Linux Cc: Arnd Bergmann , Stephen Warren , Stephen Warren , Rob Herring , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Olof Johansson , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: linux-tegra@vger.kernel.org On 09/26/2012 03:44 AM, Russell King - ARM Linux wrote: > 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. Will those of us not interested in a single kernel binary that works everywhere be able to configure an ARM kernel image without a lot of bloat? -- Tim ============================= Tim Bird Architecture Group Chair, CE Workgroup of the Linux Foundation Senior Staff Engineer, Sony Network Entertainment ============================= From mboxrd@z Thu Jan 1 00:00:00 1970 From: tim.bird@am.sony.com (Tim Bird) Date: Wed, 26 Sep 2012 06:48:16 -0700 Subject: [RFC PATCH 0/3] ARM: uncompress.h multi-platform enablement In-Reply-To: <20120926104421.GA7040@n2100.arm.linux.org.uk> References: <1348613212-21897-1-git-send-email-swarren@wwwdotorg.org> <201209261038.36223.arnd@arndb.de> <20120926104421.GA7040@n2100.arm.linux.org.uk> Message-ID: <506307A0.7010701@am.sony.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 09/26/2012 03:44 AM, Russell King - ARM Linux wrote: > 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. Will those of us not interested in a single kernel binary that works everywhere be able to configure an ARM kernel image without a lot of bloat? -- Tim ============================= Tim Bird Architecture Group Chair, CE Workgroup of the Linux Foundation Senior Staff Engineer, Sony Network Entertainment =============================