[U-Boot] [RFC] ARM ISA/cpu/SoC code organization for cache and other functions

[Albert ARIBAUD <albert.u.boot@aribaud.net>]

Le 14/10/2011 06:43, Mike Frysinger a ?crit :
> On Thursday 15 September 2011 17:42:12 Albert ARIBAUD wrote:
>> The object files shall be linked in decreasing precedence order, i.e.
>> SoC file first, then cpu file, then isa file, then lib last, so that for
>> each cache op, the weak symbol mechanism uses the most specific one.
>
> as long as the weak symbols don't cause a pain in terms of making sure the
> right one is selected.  having one depth of weak and strong is fine, but two
> deep sounds like it could be fragile.

I did some checks, and the symbol take is always the first one met by 
the linker.

> i wonder if cascading aliases would work ?  that way each symbol only has one
> weak/strong pair to deal with.  hopefully it's not too confusing ?
>
>>           (isa)   (cpu)     SoC)
>> arch/arm
>>           /armv5t/
>>                   cache-ops.c
>
> __weak void arm_isa_icache_flush(...) { ... }
> void icache_flush(...) __attribute__((alias("arm_isa_icache_flush")));
>
>>                   arm926ejs/
>>                             cache-ops.c
>
> __weak void arm_cpu_icache_flush(...) { ... }
> void arm_isa_icache_flush(...) __attribute__((alias("arm_cpu_icache_flush")));
>
>>                             orion5x/
>>                                     cache-ops.c
>
> void arm_soc_icache_flush(...) { ... }
> void arm_cpu_icache_flush(...) __attribute__((alias("arm_soc_icache_flush")));
> -mike

How would priority order work?

Amicalement,
-- 
Albert.