Hi Sascha, Le Mon, 9 Jul 2012 09:09:39 +0200, Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> a écrit : > We have the following in the tree: > > |commit af42feb9d255bc3ea3b514180f265479ea8834f9 > |Author: Enrico Scholz <enrico.scholz@xxxxxxxxxxxxxxxxx> > |Date: Mon Jan 2 11:49:17 2012 +0100 > | > | ARM: set SCTRL[A] only when architecture does not support unaligned access > | > | Recent gcc generates code with unaligned access when architecture > | supports it. Setting A bit unconditionally causes data-aborts on such > | code rendering barebox unusable. > | > | Signed-off-by: Enrico Scholz <enrico.scholz@xxxxxxxxxxxxxxxxx> > | Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > > What the patch tried is correct: We should set the A bit only when the architecture > does not support unaligned accesses. To figure out whether the architecture supports > unaligned accesses the patch tested for the U bit which is wrong. The U bit may be > 0 after a reset, so instead of testing for the U bit we have to set it. This can > be done on armv6 and later. All others have the A bit set to trap unaligned accesses. > > Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > --- > > Enrico, can you confirm this is correct? > > Thanks > Sascha > > arch/arm/cpu/start.c | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-) > > diff --git a/arch/arm/cpu/start.c b/arch/arm/cpu/start.c > index 3c282ee..523179d 100644 > --- a/arch/arm/cpu/start.c > +++ b/arch/arm/cpu/start.c > @@ -81,13 +81,11 @@ void __naked __bare_init reset(void) > r &= ~(CR_M | CR_C | CR_B | CR_S | CR_R | CR_V); > r |= CR_I; > > - if (!(r & CR_U)) > - /* catch unaligned access on architectures which do not > - * support unaligned access */ > - r |= CR_A; > - else > - r &= ~CR_A; > - > +#if __LINUX_ARM_ARCH__ >= 6 > + r |= CR_U; > +#else > + r |= CR_A; > +#endif > > #ifdef __ARMEB__ > r |= CR_B; Tested-by: Eric Bénard <eric@xxxxxxxxxx> this patch fix the crash we had in show_progress. Eric _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
