On 02/04/2015 04:11 AM, Masahiro Yamada wrote: > Hi Michal, > > > On Tue, 3 Feb 2015 10:11:39 +0100 > Michal Simek <michal.si...@xilinx.com> wrote: > >> Hi Simon, >> >> On 02/03/2015 03:02 AM, Masahiro Yamada wrote: >>> Hi. >>> >>> >>> On Mon, 2 Feb 2015 16:57:15 -0700 >>> Simon Glass <s...@chromium.org> wrote: >>> >>>> Hi Michal, >>>> >>>> On 2 February 2015 at 08:31, Michal Simek <michal.si...@xilinx.com> wrote: >>>>> Targets with CONFIG_NEEDS_MANUAL_RELOC do not use REL/RELA >>>>> relocation (mostly only GOT) where functions aray are not >>>>> updated. This patch is fixing function pointers for DM core >>>>> and serial-uclass to ensure that relocated functions are called. >>>>> >>>>> Signed-off-by: Michal Simek <michal.si...@xilinx.com> >>>>> --- >>>>> >>>>> drivers/core/root.c | 64 >>>>> ++++++++++++++++++++++++++++++++++++++++++ >>>>> drivers/serial/serial-uclass.c | 16 +++++++++++ >>>>> 2 files changed, 80 insertions(+) >>>> >>>> How long will we have to carry this patch? It seems that if we add any >>>> new driver we will have to add more code like this? >>> >>> >>> >>> This patch is unfortunate. >>> Can we discontinue CONFIG_NEEDS_MANUAL_RELOC some day? >> >> This patch (or similar one) has to be alive when we have platform >> which requires CONFIG_NEEDS_MANUAL_RELOC for full u-boot. >> There is an option to move to REL/RELA but the question is if >> all platforms have it/support it. Unfortunately I think that >> it will be in the tree for a long time. >> >>> >>> If we use SPL, we do not have to relocate code, I think. >> >> SPL doesn't have relocation that's why this code is not used there. >> > > It is not what I meant. > > > If SPL can directly load the main u-boot image > to the DRAM address where it is linked, > we do not relocate the code in the main image.
Current behavior is that SPL is reading u-boot.img entry point which can be in any location and jump to it and u-boot self relocate to the end of memory. If SPL adds u-boot directly to the location where it should run after relocation then relocation is not needed. To ensure this capability (based on my poor GOT/REL/RELA) experience it means that SPL loads u-boot to that location and patch REL/RELA section based on this location and internal relocation should be skipped. This is definitely doable for REL/RELA case and it can also speedup boot process (I don't think there is easy way how to solve this with just GOT relocation because of that MANUAL_RELOC code which is patching arrays with function pointers). Thanks, Michal _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
