Le 01/11/2010 20:44, Graeme Russ a écrit : > On Tuesday, November 2, 2010, Albert ARIBAUD<albert.arib...@free.fr> wrote: >> Le 01/11/2010 20:23, Wolfgang Denk a écrit : >>> Dear Albert ARIBAUD, >>> >>> In message<4ccef2e4.5080...@free.fr> you wrote: >>>> >>>> Also, I understand why the second RFC change I did was harmful to tx25. >>>> Contrary to u-boot itself, u-boot-spl is not compiled to be position >>>> independent; it actually loads at a given address then copies itself, >>>> without relocating, to its home location. >>> >>> It copies _itself_? Not the U-Boot payload? >>> >>> Heiko, is this intentional? Do we really first load the whole image, >>> then copy the U-Boot payload to some other address, then relocate it >>> to yet another one? >> >> I haven't been clear. >> >> The boot ROM or IPL loads u-boot-spl in RAM at a fixed location and >> jumps to it. >> >> u-boot-spl copies itself at its intended location if not already there, >> and jumps to tiself at that new location. >> >> u-boot-spl loads u-boot at a fixed location and jumps to it. >> >> u-boot relocates (copies and fixes up) itself at top of ram if not >> already there, and jumps to itself at that new location. >> > > Wow, what a terrible waste! > > Why does u-boot-spl need to relocate?
As I said, u-boot-spl does not relocate, it only copies itself to its link-time location and jumps there, and it does this only if loaded somewhere else to boot (if I may say so). *Usually* it will be loaded at the right place and thus won't copy itself and jump to itself. It still takes up some space, though. The copy and jump could actually be #ifdef's on CONFIG_NAND_SPL if everyone thinks it is safe -- please comment quickly as I'm preparing a patch set and that could go in it if agreed to. > Can't u-boot-spl load AND relocate u-boot, or does u-boot-spl have > tight space constraints? It has; it comes from a (usually small) NAND page. > Regards > > Graeme Amicalement, -- Albert. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot