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

[Simon Glass]

Hi Mike,

On Wed, Aug 31, 2011 at 7:44 AM, Mike Frysinger <vapier at gentoo.org> wrote:
> On Wednesday, August 31, 2011 01:30:56 Simon Glass wrote:
>> On Tue, Aug 30, 2011 at 9:36 PM, Mike Frysinger wrote:
>> > On Tuesday, August 30, 2011 17:13:51 Simon Glass wrote:
>> >> 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.
>> >
>> > $ cat arch/arm/include/asm/arch-tegra3/clock.h
>> > #include <asm/arch-tegra2/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.
>> >
>> > maybe create asm/arch-tegra/ for the common stuff and have the other
>> > tegras include that for common stuff ?
>>
>> That sort-of works. My concern is when drivers start doing
>>
>> #include <asm/arch-tegra/clock.h>
>>
>> Doesn't that break the rule that architecture should be set at config
>> time? Not that it matters much I suppose, since the only drivers
>> including this file are architecture-specific.
>
> the driver is broken then ? :)
>
> easy to catch this ala bits/ C library headers:
> arch-tegra2/clock.h:
> #ifndef _ARCH_TEGRA_CLOCK_H_
> #define _ARCH_TEGRA_CLOCK_H_
> ...
> #include <asm/arch-tegra/clock.h>
> ...
> #endif
>
> arch-tegra3/clock.h:
> #ifndef _ARCH_TEGRA_CLOCK_H_
> #define _ARCH_TEGRA_CLOCK_H_
> ...
> #include <asm/arch-tegra/clock.h>
> ...
> #endif
>
> asm/arch-tegra/clock.h:
> #ifndef _ARCH_TEGRA_CLOCK_H_
> # error "do not include this header directly"
> #endif
> #ifndef _ARCH_TEGRA_COMMON_CLOCK_H_
> #define _ARCH_TEGRA_COMMON_CLOCK_H_
> ...
> #endif
> -mike
>

Thank you. I have gone with having

asm/arch-tegra/clock.h

for the generic stuff and

asm/arch-tegra2/clock.h, asm/arch-tegra3/clock.h

which include that. It seems to work ok.

Regards,
Simon