On Tue, 2020-01-28 at 08:08 -0600, Rob Herring wrote: > On Tue, Jan 28, 2020 at 7:43 AM Tom Rini <trini@xxxxxxxxxxxx> wrote: > > > > [...] > > I still believe you have things wrong. There's not an unaligned access > > problem that libfdt needs to care about. ARM doesn't need help handling > > unaligned accesses. The only problem that's been reported is from when > > a user got themselves so far off in the weeds that nothing else matters. > > I think while the vast majority of DTBs don't have anything that would > cause unaligned accesses, that's not guaranteed by the FDT format. > libfdt needs to handle the worst case. > > What about ARMv5 and v4 which don't universally support unaligned > accesses or any other architecture. Do all mips, openrisc, riscv, arc, > microblaze, xtenza, etc. support unaligned accesses? > Unaligned support is optional even on armv6 and armv7. For quite a long time freebsd ran armv7 chips with strict alignment (mostly because we had no real need to do otherwise until people started complaining that 3rd-party opensource software often failed on freebsd because it's written with the assumption that the whole world is linux, and linux used relaxed alignment). -- Ian
