Hi Måns, On Tue, 15 Oct 2013 17:29:24 +0100, Måns Rullgård <[email protected]> wrote:
> Albert ARIBAUD <[email protected]> writes: > > > Hi Måns, > > > > On Tue, 15 Oct 2013 16:23:44 +0100, Måns Rullgård <[email protected]> > > wrote: > > > >> On the compiler side, gcc traditionally did not issue unaligned > >> load/store instructions on ARM. > > > > Please be specific: gcc did not emit *native* unaligned accesses. > > Please explain what you mean by "native unaligned access". By this I mean an unaligned access performed with a single transfer, initiated by a single processor instruction, as opposed to an unaligned access performed with a series of smaller, aligned, transfers (and possibly additional operations) initiated by a sequence of processor instructions (emulated, if you will). Prior to 4.7, gcc did emit unaligned accesses if instructed to at the source code level; they were however emulated. From 4.7 onward, it was possible to choose whether unaligned transfers should be performed native or emulated, the default being native for ARMv6+, and emulated for the rest. Amicalement, -- Albert. _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
