From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?ISO-8859-1?Q?Andreas_Bie=DFmann?= Date: Fri, 26 Aug 2011 13:22:42 +0200 Subject: [U-Boot] [PATCH V3 3/8] arm: Add savebp implementation for arm In-Reply-To: <4E57711D.6020103@gmail.com> References: <1314182363-25732-1-git-send-email-simonschwarzcor@gmail.com> <1314261196-23197-1-git-send-email-simonschwarzcor@gmail.com> <1314261196-23197-4-git-send-email-simonschwarzcor@gmail.com> <4E562D3A.4090103@gmail.com> <4E57711D.6020103@gmail.com> Message-ID: <4E578202.5060400@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Simon, Am 26.08.2011 12:10, schrieb Simon Schwarz: > Dear Andreas, > >> BTW while reading this patch I got another idea to solve problem 'how >> get we saved the boot information to'. >> The required information regardless of whether it is ATAGS or FDT is >> only a blob at some place in ram after the 'bootm x' commands used in >> 'Add savebp command'. Saving a blob from location X with size Y to >> location Z is easy and already implemented. >> >> So the only required thing is to get the 'blob' prepared in RAM. In my >> opinion this could be a subcommand of bootm instead of a new command. >> >> How about: >> >> ---8<--- >> # bootm savebp >> ...done boot information is @0x80000100 with size 0x100 >> # nandecc hw >> # nand erase ... >> # nand write 80000100 ... >> --->8--- > > This was actually my first implementation (although not with a switch): > http://thread.gmane.org/gmane.comp.boot-loaders.u-boot/102669 > > It was criticised because saving the parameter images is not the > responsibility of bootm - which is true. Although adding a switch would > be a cleaner solution than my first implementation - would that be > acceptable? > > How about implementing it as bootm subcommand? Another question, how often will one change the boot information for SPL booting? I guess most people will use the normal u-boot to test different configurations and start directly into the OS. When one has some satisfying configuration he will store this for SPL boot into flash regardless whether it is a separate command or a list of commands. The current solution (having savebp command utilize do_bootm()) couples these two commands in a way which may lead to problems in future (but I don't know what others think about ... Wolfgang?). I vote for a well documented guide or an example script to gather the boot information and store it for SPL booting (at least for this patch set). I know your bachelor thesis filing date is end of September and I would appreciate to have this functionality in before. The rest of this series seems quite good to me. Except for some minor changes to the arm-bootm prep command ... but read my answer to that patch. best regards Andreas Bie?mann