Hi Helmut, On Wed, 02 Jul 2014 09:04:46 +0200, Helmut Raiger <helmut.rai...@hale.at> wrote:
> Hi, > > Hi, > > > > the commit 41623c91 breaks the SPL on i.mx31 platforms. > > The original startup code (start.S) was position independent to > > allow relocation in board_init_f. This is necessary as the internal > > RAM used by the IPL to load the first 2kB from NAND is also > > used by the NAND controller to buffer pages. > > As far as the issue goes: where and how exactly is the code not > > position independent now? > The first statement is now: > > ldr pc, _reset > _reset: .word reset > > reset is an address generated by the linker (here 0x87dc0060). > Originally this was: > > b reset > > which is a relative branch (here 0x60 bytes forward). > > I have to add, that changing this back does not fix the issue, something > else is in disorder. > I'm still working on it. > > >>> Does changing the startup code back to PIC generate any > >>> drawbacks on other ARM platforms? > > How would this changing back to PIC be implemented? Not by reverting > > the patch, I hope. > No, it will only be a minor change, I think, but I thought there might > have been an additional intention behind the change to position > dependent code. One could link the first part to 0xB8000000 > (the original position of the SPL when loaded by the IPL) and > the part after the relocation to CONFIG_SPL_TEXT_BASE. > >>> What was the intention of the change besides unifying? > > Any other intent would be stated in the commit message. > Ok, so the PIC issue was just an oversight. > > > Maybe Albert, Stefano or Magnus could help? > > I don't have mx31 hardware either. > > > > > It seems we are the only ones still dealing with this old lad ;-) Full position independence was a lucky side effect of the code, not an intended feature; relocation is precisely here because moving code around usually won't work. However, no relocation record (relative or other) are generated for the indirect vectors, so that'll need a fix as well. It basically works in U-Boot because most of the targets get loaded at their link-time base address, so the indirect vectors are correct. I suspect in your case, SPL was linked for one address and gets jumped into at another address. Can you tell me which board exactly you are experiencing the issue on? > Helmut Amicalement, -- Albert. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
