Dear Zhong Hongbo, this is arm related and should therefore apply to all the different arch/arm/cpu/*/start.S (as long as they have SPL support).
On 05.07.2012 16:35, Zhong Hongbo wrote: > From: Zhong Hongbo <bocui...@gmail.com> > > In currently, when __bss_start is equal to __bss_end__, > The bss loop will clear all the things in memory space. I ask myself why there is no bss at all. Have you just initialized data in your spl code? > > But just only when __bss_end__ greater than __bss_start__, > we do the clear bss section operation. > > Signed-off-by: Hongbo Zhong <bocui...@gmail.com> > --- > arch/arm/cpu/armv7/start.S | 9 ++++++--- > 1 files changed, 6 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S > index 22a3ced..2e583ee 100644 > --- a/arch/arm/cpu/armv7/start.S > +++ b/arch/arm/cpu/armv7/start.S > @@ -259,10 +259,13 @@ clear_bss: > #endif > mov r2, #0x00000000 /* clear */ > > -clbss_l:str r2, [r0] /* clear loop... */ > +clbss_l: > + cmp r1, r0 > + bls clbss_end > + str r2, [r0] /* clear loop... */ > add r0, r0, #4 > - cmp r0, r1 > - bne clbss_l > + b clbss_l > +clbss_end: Looks sane, I maybe had checked before clbss_l, jumped over clear loop if r0 and r1 equal (to emphasize the fact that this is a check for entry correctness) and wouldn't change the loop at all. To be more precise we could also check if end is after start. > > /* > * We are done. Do not return, instead branch to second part of board > Best regards Andreas Bießmann _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
