[PATCH v3] powerpc/boot: Don't always pass -mcpu=powerpc when building 32-bit uImage

[Pali Rohár]

On Saturday 24 December 2022 18:44:52 Pali Rohár wrote:
> On Thursday 08 December 2022 19:57:39 Christophe Leroy wrote:
> > Le 08/12/2022 à 20:16, Pali Rohár a écrit :
> > > On Sunday 28 August 2022 17:43:53 Christophe Leroy wrote:
> > >> Le 28/08/2022 à 19:41, Pali Rohár a écrit :
> > >>> On Sunday 28 August 2022 17:39:25 Christophe Leroy wrote:
> > >>>> Le 28/08/2022 à 19:33, Christophe Leroy a écrit :
> > >>>>>
> > >>>>>
> > >>>>> Le 28/08/2022 à 11:56, Pali Rohár a écrit :
> > >>>>>> When CONFIG_TARGET_CPU is specified then pass its value to the compiler
> > >>>>>> -mcpu option. This fixes following build error when building kernel with
> > >>>>>> powerpc e500 SPE capable cross compilers:
> > >>>>>>
> > >>>>>>        BOOTAS  arch/powerpc/boot/crt0.o
> > >>>>>>      powerpc-linux-gnuspe-gcc: error: unrecognized argument in option
> > >>>>>> ‘-mcpu=powerpc’
> > >>>>>>      powerpc-linux-gnuspe-gcc: note: valid arguments to ‘-mcpu=’ are:
> > >>>>>> 8540 8548 native
> > >>>>>>      make[1]: *** [arch/powerpc/boot/Makefile:231:
> > >>>>>> arch/powerpc/boot/crt0.o] Error 1
> > >>>>>
> > >>>>> corenet64_smp_defconfig :
> > >>>>>
> > >>>>>      BOOTAS  arch/powerpc/boot/crt0.o
> > >>>>> powerpc64-linux-gcc: error: missing argument to '-mcpu='
> > >>>>> make[1]: *** [arch/powerpc/boot/Makefile:237 : arch/powerpc/boot/crt0.o]
> > >>>>> Erreur 1
> > >>>>> make: *** [arch/powerpc/Makefile:253 : uImage] Erreur 2
> > >>>>>
> > >>>>>
> > >>>>
> > >>>> Seems like in fact, E5500_CPU and E6500_CPU are not taken into account
> > >>>> in CONFIG_TARGET_CPU, and get special treatment directly in
> > >>>> arch/powerpc/Makefile.
> > >>>>
> > >>>> This goes unnoticed because of CFLAGS-$(CONFIG_TARGET_CPU_BOOL) +=
> > >>>> $(call cc-option,-mcpu=$(CONFIG_TARGET_CPU))
> > >>>>
> > >>>> I think we need to fix that prior to your patch.
> > >>>
> > >>> It looks like that CONFIG_TARGET_CPU is broken.
> > >>>
> > >>>     $ make ARCH=powerpc corenet64_smp_defconfig CROSS_COMPILE=powerpc64-linux-gnu-
> > >>>     ...
> > >>>     # configuration written to .config
> > >>>
> > >>>     $ grep CONFIG_TARGET_CPU .config
> > >>>     CONFIG_TARGET_CPU_BOOL=y
> > >>>
> > >>> CONFIG_TARGET_CPU_BOOL is set but CONFIG_TARGET_CPU not!
> > >>
> > >> Yes, because there is no default value for E5500_CPU and E6500_CPU. We
> > >> need to add one for each.
> > > 
> > > With "[PATCH v1] powerpc/64: Set default CPU in Kconfig" patch from
> > > https://lore.kernel.org/linuxppc-dev/3fd60c2d8a28668a42b766b18362a526ef47e757.1670420281.git.christophe.leroy@csgroup.eu/
> > > this change does not throw above compile error anymore.
> > 
> > 
> > That patch should land in powerpc/next soon. When it has landed, could 
> > you resent this patch so that snowpatch checks the build again ?
> 
> Yes. But I'm still waiting because patch is not in powerpc/next yet.

Seems that it still has not landed. Any suggestions to move forward?

> > Because at the time being it is flagged as "failed", see 
> > https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220828095659.4061-1-pali@kernel.org/
> > 
> > Christophe