From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: Change of TEXT_OFFSET for multi_v7_defconfig Date: Fri, 18 Apr 2014 09:41:41 +0100 Message-ID: <20140418084141.GB24070@n2100.arm.linux.org.uk> References: <534D0D91.8020406@linaro.org> <534EAD6C.3040502@codeaurora.org> <20140417201645.GU24070@n2100.arm.linux.org.uk> <20140417213502.GX24070@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from gw-1.arm.linux.org.uk ([78.32.30.217]:39504 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751034AbaDRIma (ORCPT ); Fri, 18 Apr 2014 04:42:30 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Rob Herring Cc: Nicolas Pitre , Peter Maydell , Daniel Thompson , Joel Fernandes , linux-arm-msm , Stephen Boyd , Peter Crosthwaite , QEMU Developers , Christopher Covington , "linux-arm-kernel@lists.infradead.org" , Kumar Gala On Thu, Apr 17, 2014 at 09:53:23PM -0500, Rob Herring wrote: > On Thu, Apr 17, 2014 at 4:35 PM, Russell King - ARM Linux > wrote: > > No. You simply can't eliminate any of the above - each one has been > > negotiated through quite an amount of discussion with relevant parties > > and/or due to technical requirements and they just can't be magic'd > > away. > > > > Plus the ARM64 image format is different from our zImage format. It > > would make far *more* sense to align our Image format with our zImage > > format so existing boot loaders which look for the zImage magic numbers > > can boot plain Image files too. > > > > Moreover, since we could *never* align zImage with the ARM64 format, > > why on earth would we want to start using the ARM64 format for the > > Image format? > > I'm not talking about zImage. I'm talking about Image files only. The > arm64 Image header could be added to ARM Image files and that would > not hurt or change a thing for existing users. The cost is 64 bytes. No it isn't. The cost is 64-bytes *and* user confusion with two completely different "headers" for no reason what so ever. Why use the ARM64 version and then have it *block* existing boot loaders which look for the zImage magic from being able to boot an Image. It's a much saner idea to use the ARM32 zImage header than to use the ARM64 version - or nothing at all. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it.