The values all changed and are dependent on RAM size, but their relationship to one another didn't - they all just increased by 0x7fff0000. So practically speaking, we do need to know where the bss is at link time - its address is not dynamic like the malloc pool or stack - its tied directly to the address of the other sections at link time. (Unless we added some bss-specific fixups I imagine)
Right, that's the current situation.
My suggestion was NOT to put the bss at a fixed _offset_ to the U-Boot image, but to a fixed absolute address. My hope is that this might simplify the linker scripts at the cost of adding a little code to the relocation routine - for addresses in the bss we would have to add a different relocation offset.
I think I see what you're getting at. If we have a bss-specific fixup routine I don't give a hoot where the bss is located at link time. Its just that that bss-aware fixup routine doesn't exist right now:)
It seems like a clean solution. Adding a bss-aware fixup routine or putting the bss after the U-Boot image both seem good to me. The bss-aware fixup routine has a clearer readelf output and slightly more complicated code while the bss-after-uboot change has a misleading readelf output and simpler code. In any case I'd give a thumbs up to either of them.
Best, Peter