[U-Boot] Common arch-specific header files for SOCs

[Simon Glass]

Hi,

I am looking at generalizing Tegra20 to support other Tegra parts. I
can easily create

arch/arm/cpu/armv7/tegra-common

and I see that this is done for OMAP and Samsung with this little
fragment in the Makefile:

ifeq ($(SOC),omap3)
LIBS += $(CPUDIR)/omap-common/libomap-common.o
endif
ifeq ($(SOC),omap4)
LIBS += $(CPUDIR)/omap-common/libomap-common.o
endif

ifeq ($(SOC),s5pc1xx)
LIBS += $(CPUDIR)/s5p-common/libs5p-common.o
endif
ifeq ($(SOC),s5pc2xx)
LIBS += $(CPUDIR)/s5p-common/libs5p-common.o
endif

Not a long term solution with dozens of SOCs, but fine for now.

But I also have common header files and it isn't so clear what to do there.

The arch/arm/include/asm/arch symlink needs to point to arch-tegra2 in
my case, which is fine, but I also want to be able to include common
files.

#include <asm/arch/clock.h>

This points to arch/arm/include/asm/arch-tegra2/clock.h but this would
not be available from a tegra3 architecture, for example.

One solution is a symlink inside arch-tegra2 to what is effectively
arch/arm/include/asm/tegra-common

and then add this path to the flags somehow. Then I can do, in both
tegra2 and tegra3 code:

#include <asm/arch/common/clock.h>

Any other suggestions? It almost feels like we need an 'SOC family'
field in boards.cfg (as distinct from SOC). Then we could perhaps have
this work automatically.

Regards,
Simon