Dear Leon, in message <[EMAIL PROTECTED]> you wrote: > > triggered by the e-mail below (which solved my issue, thanks Kim) I > have the following question: > > For how long can I expect current u-boot (say 1.3.4) to be forward > compatible with newer Linux kernels?
I think chances are pretty good. Please keep in mind that we're right in the middle of a really big change - the merging of the arch/ppc and arch/ppc64 code into a common arch/powerpc tree is something that hits many areas pretty heavily, and the device tree support which many things depend upon is still a (fast) moving target. But even today you can build a current Linux kernel using the cuImage wrapper and boot it on an old (say, version 1.2.0) U-Boot. Please do not confuse compatibility with "having all the latest and greatest new interfaces as well". I think you have to get used to the thought that the Linux kernel is undergoing serious changes right now (which means you cannot consider it stable enough to use the latest version in a project where long- term compatibility is an issue). > It seems the u-boot from only half a year old cannot boot a current > Linux kernel (!). Only if you try to use the latest features. Use a cuImage, and it should just work fine. > I typically work on products where the initial boot loader is adapted > to provide fail-safe upgrades and itself is never upgraded to prevent > the chance of non-flashable (bricked) products in the very small > chance something goes wrong during the boot loader update. Been there, too. > How do people deal with using u-boot in a fail-safe environment where > the chance of brickage must be zero and the (initial) bootloader > itself cannot be updated? You will probably have to accept that software updates are restricted to certain versions. If you started with a root file system build around a 2.4 Linux kernel, you will probably have problems when trying to use a current 2.6 kernel with this file system image as well. There may (or may not) be compatibility layers (like the cuImage wrapper) that extend that period, but there is no guarantee. > Should I plan for a second stage loader? You already have one - Linux. Use kexec if you really think you must. > Also, is there any plan to add fail-safe features to u-boot? What are you thinking of? Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: [EMAIL PROTECTED] "Wagner's music is better than it sounds." - Mark Twain ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ U-Boot-Users mailing list U-Boot-Users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/u-boot-users
