On Tue, Oct 5, 2010 at 4:34 PM, Wolfgang Denk <[email protected]> wrote: > Dear Graeme Russ, > > In message <[email protected]> you > wrote: >> >> Can NAND SPL initialise and size memory before loading U-Boot into RAM? > > It has to. You cannot load into and run from uninitialized RAM ;-) > >> If so, could the relocation code be added to NAND SPL so only one copy >> operation is performed? > > I'm afraid it cannot, due to size limitations. The NAND loader often > hast to fit into as little a 2 or 4 KiB... >
For x86, the actual relocation calculations can be done in a probably a few dozen bytes of code. It contains: - One offset calculation - A single tight loop - Two comparisons (probably not needed in the generic case as they are used to filter out x86 specific code outside .text) - An offset addition If the only constraint is space then it _may_ be possible in some scenarios (although I do acknowledge that previous trival changes have caused the size constaint to be violated) Regards, Graeme _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
