Hi Greg, On Fri, Jun 08, 2012 at 10:19:43PM +1000, Greg Ungerer wrote: > Hi Philippe, > > On 06/08/2012 08:39 PM, Philippe De Muyter wrote: >> On Fri, Jun 08, 2012 at 03:43:00PM +1000, g...@snapgear.com wrote: >>> From: Greg Ungerer<g...@uclinux.org> >>> >>> All current ColdFire CPUs are able to support unaligned memory accesses. >>> So remove the CONFIG_CPU_HAS_NO_UNALIGNED option selection for ColdFire. >>> >>> It seems that the current restriction was inherrited from the early >>> non-MMU >>> support for the basic 68000 proecssors - which do not support unaligned >>> accesses. >> >> It seems that the first ColdFires needed the restriction : >> >> I read in the "MCF5200 ColdFire Family ProgrammerÆs Reference Manual" >> : >> >> The ColdFire processor default configuration supports word- and >> longword-sized operand references on 0-modulo-2 and 0-modulo-4 >> addresses, respectively. All other references are defined as >> misaligned accesses. Any attempt to access a misaligned operand >> generates an address-error exception, unless the optional hardware >> module for handling misalignment is present. This misalignment >> module converts any misaligned operand references into a series >> of aligned bus cycles to access the data. The existence of the >> misalignment module is implementation-dependent and is documented >> in the appropriate ColdFire userÆs manual.
I mentionned that only to make you able to soften the commit comment :) > > I wish Freescale really did make that clear within the doco for each > part! > > The oldest (and I assume simplest) part we support is the 5206, and it > does explicitly state in the MCF5206UM that it supports unaligned > accesses (Section 6.6). It is not as clear as this in some of the > other CPU/SoC User Manuals that I looked through. > > I am pretty confident that all the parts we currently support in Linux > do unaligned accesses. I agree. And if some parts did not implement it, we'd see it quickly. Regards Philippe _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
