[U-Boot] [PATCH 2/2] SPL: Allow ARM926EJS to avoid compiling in the CPU support code

Marek Vasut
2011-10-21T23:45:08Z

On Saturday, October 22, 2011 01:08:43 AM Albert ARIBAUD wrote:
> Le 22/10/2011 00:46, Marek Vasut a ?crit :
> > On Saturday, October 22, 2011 12:44:06 AM Albert ARIBAUD wrote:
> >> Le 22/10/2011 00:00, Marek Vasut a ?crit :
> >>> On Friday, October 21, 2011 11:52:23 PM Albert ARIBAUD wrote:
> >>>> Hi Marek,
> >>>>
> >>>> Le 21/10/2011 22:44, Marek Vasut a ?crit :
> >>>>> On Thursday, October 06, 2011 02:13:26 AM Marek Vasut wrote:
> >>>>>> This allows the SPL to avoid compiling in the CPU support code.
> >>>>>>
> >>>>>> Signed-off-by: Marek Vasut<marek.vasut@gmail.com>
> >>>>>> Cc: Stefano Babic<sbabic@denx.de>
> >>>>>> Cc: Wolfgang Denk<wd@denx.de>
> >>>>>> Cc: Detlev Zundel<dzu@denx.de>
> >>>>>> Cc: Scott Wood<scottwood@freescale.com>
> >>>>>> ---
> >>>>>>
> >>>>>> arch/arm/cpu/arm926ejs/Makefile | 7 +++++++
> >>>>>> 1 files changed, 7 insertions(+), 0 deletions(-)
> >>>>>>
> >>>>>> diff --git a/arch/arm/cpu/arm926ejs/Makefile
> >>>>>> b/arch/arm/cpu/arm926ejs/Makefile index 930e0d1..3f9b0f1 100644
> >>>>>> --- a/arch/arm/cpu/arm926ejs/Makefile
> >>>>>> +++ b/arch/arm/cpu/arm926ejs/Makefile
> >>>>>> @@ -28,6 +28,13 @@ LIB = $(obj)lib$(CPU).o
> >>>>>>
> >>>>>> START = start.o
> >>>>>> COBJS = cpu.o
> >>>>>>
> >>>>>> +ifdef CONFIG_SPL_BUILD
> >>>>>> +ifdef CONFIG_SPL_NO_CPU_SUPPORT_CODE
> >>>>>> +START :=
> >>>>>> +COBJS :=
> >>>>>> +endif
> >>>>>> +endif
> >>>>>> +
> >>>>>>
> >>>>>> SRCS := $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
> >>>>>> OBJS := $(addprefix $(obj),$(COBJS) $(SOBJS))
> >>>>>> START := $(addprefix $(obj),$(START))
> >>>>>
> >>>>> Hi Albert,
> >>>>>
> >>>>> can we get this applied please?
> >>>>
> >>>> I still don't understand what this is supposed to do -- why not
> >>>> linking this code is required.
> >>>>
> >>>> Amicalement,
> >>>
> >>> Hi Albert,
> >>>
> >>> I use very different start.S in SPL. And I don't need cpu.o at all.
> >>
> >> That I understand; but is there a /problem/ in linking cpu.o in?
> >
> > I suppose it'll be optimized out at link time ?
>
> That indirectly answers my question: what you want to achieve is
> removing dead code.

The code IS USED in U-Boot, but IS NOT USED in SPL !

>
> Now, about your question, you can check this if you build the board you
> intend to apply this to, and do an objdump of the generated SPL: you'll
> see if the cpu.o functions are present or not.
>
> (my point being that if cpu.o is to disappear because its functions are
> either useless or should move elsewhere, then the interest of a patch
> making cpu.o optional is short-lived.)

I just prodded Hong about his cache patches.
>
> > Cheers
>
> Amicalement,