Honored Contributor
Honored ContributorOne of the problems supporting misaligned transfers is that you can get a TLB miss and/or page fault (or even an external bus error) when accessing the second word. This is rather problematical to deal with properly - especially for writes and what are supposed to be locked bus transfers (which the nios and the Avalon MM bus don't support).
It might be worth looking at the code generated by gcc for sparc - to see if it can generate multiple memory accesses for pointers to 'packed' integers. If it does (or possibly anyway!) it might be possible to modify gcc's code generatotor to detect the 'packed' property and perform the required cycles. For someone who understands gcc code generation that probably isn't that hard!
