From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dirk Behme Date: Wed, 8 Feb 2012 07:51:56 +0100 Subject: [U-Boot] [PATCH] arm: Add option to disable code relocation In-Reply-To: <20120207233628.0F9A282373@gemini.denx.de> References: <1328424259-12914-1-git-send-email-sjg@chromium.org> <4F2F9294.4030805@gmail.com> <201202061427.02208.vapier@gentoo.org> <4F30C794.50206@de.bosch.com> <20120207232317.D164482373@gemini.denx.de> <20120207233628.0F9A282373@gemini.denx.de> Message-ID: <4F321B8C.3090907@de.bosch.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 08.02.2012 00:36, Wolfgang Denk wrote: > Dear Graeme Russ, > > In message you wrote: >>> If SPL was to determing the relocation address, it would also have to >>> read the environment, because there are a number of environment >>> variables which can cause (dynamically) the relocation address to >>> change. >> But this is not neccessarily the case for every board (or even every arch) > > Not neccessarily, but possible. > >> For those boards/arches which CAN calculate the relocation address (either >> because it is fixed do to npn-variable RAM size, or fixed in relation to >> the maximum RAM address) why should we prohibit a method of skipping the >> redundant copy operation in a way which is 100% transparent to everyone >> else? > > Can we please focus on unifying the boot process first, before we try > to come up with micro-optimizations? > > Most of the people who complain here that they need to skip > relocation are probably wrong in at least two accounts: > > - They are not actually talking about relocation at all. > - They don't base their accessment on any real, measured timings, or > otherwise they would start optimizing completely different areas of > the code. Maybe they are looking at all areas (including the different ones) of possible optimizations. And this thread is only one topic (note 1). Best regards Dirk note 1: I agree that the different topics will give more improvement. E.g. [1]. Looking at that thread, unfortunately there is less discussion than here while it will give more improvement :( [1] http://lists.denx.de/pipermail/u-boot/2012-February/117270.html