Hello Albert, Albert ARIBAUD wrote: > Le 04/10/2010 09:27, Reinhard Meyer a écrit : >> Dear Albert ARIBAUD, >>> >>> Right now I can build (not run, mind you) u-boot for edminiv2 without >>> -fPIC/-fPIE, with -pie and a modified u-boot.lds and start.S. Almost all >>> of the .rel.dyn fixup entries are type 23, that is, relative to the base >>> address, which is good. However, here are about ten at the end which are >>> type 2 -- symbol-relative -- and I am studying them in order to see if >>> they are needed. >>> >>> If type 23 relocations are all that is needed, then a first ARM ELF >>> relocation implementation should 'simply' trade GOT vs .rel.dyn >>> relocation in start.S (I am almost there) and remove fixups in >>> board_init_r. Start.S would apply type 23 fixups only and ignore the >>> rest. Later on we could add a build stage to rewrite the .rel.dyn >>> section as suggested, by filtering out non-type-23 relocs and keeping >>> only the address part of type-23 ones, reducing the .rel.dyn table >>> roughly by half. >>> >>> The good news is, I can spare a couple more hours today on this. I'll >>> let you all know how this fares! >> >> Thats good news! How much did the image size increase with this table? > > ./MAKEALL edminiv2 results: > > text data bss dec hex filename > 141376 4388 16640 162404 27a64 ./u-boot (for GOT > reloc) > 150160 3819 16640 170619 29a7b ./u-boot (for ELF > reloc) > > u-boot.bin size in bytes: > > 145764 (for GOT reloc) > 153976 (for ELF reloc)
Huh... > The .rel.dyn table is 18472 bytes, and should eventually shrink by half, > losing about 9 KB. That would bring the u-boot.bin size down to > 145 KB, roughly the same size as GOT reloc -- plus we'd save a few code ... puuh ;-) > bytes since reloc fixup functions in board_init_r would not be needed > any more. Sounds good. And we can easy test this, by defining CONFIG_RELOC_FIXUP_WORKS for all arm boards ... >> And I am willing to test your efforts on AT91 here, maybe you can send me >> the changes to .lds and start.S beforehand so I can see what type of >> relocation info gets produced here. > > I'll post an RFC patch within one or two hours. Thanks! I am wating for it, and try your patches too. bye, Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
