[PATCH 1/3] cmd: avoid duplicate weak flush_dcache_all()

[Heinrich Schuchardt]

On 19.06.24 14:23, Ilias Apalodimas wrote:
> On Sun, 16 Jun 2024 at 20:31, Heinrich Schuchardt
> <heinrich.schuchardt at canonical.com> wrote:
>>
>> If we have multiple weak implementations of functions, the linker might
>> choose any of these. ARM and RISC-V already provide a weak implementation
>> of flush_dcache_all().
>>
>> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
>> ---
>>   cmd/cache.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/cmd/cache.c b/cmd/cache.c
>> index 0254ff17f9b..16fa0f7c652 100644
>> --- a/cmd/cache.c
>> +++ b/cmd/cache.c
>> @@ -52,11 +52,14 @@ static int do_icache(struct cmd_tbl *cmdtp, int flag, int argc,
>>          return 0;
>>   }
>>
>> +/* ARM and RISC-V define a weak flush_dcache_all() themselves. */
>> +#if !defined(CONFIG_ARM) && !defined(CONFIG_RISCV)
>>   void __weak flush_dcache_all(void)
>>   {
>>          puts("No arch specific flush_dcache_all available!\n");
>>          /* please define arch specific flush_dcache_all */
>>   }
> 
> Aren't we supposed to add a single __weak function so the linker can
> replace it? IOW why is the declaration for Arm/riscv a weak one?

Some sub-architectures override the architecture specific weak 
implementation, e.g.

arch/riscv/cpu/andes/cache.c:44:
void flush_dcache_all(void)

arch/arm/cpu/arm926ejs/cache.c:17:
void flush_dcache_all(void)

Best regards

Heinrich

> 
> Thanks
> /Ilias
>> +#endif
>>
>>   static int do_dcache(struct cmd_tbl *cmdtp, int flag, int argc,
>>                       char *const argv[])
>> --
>> 2.43.0
>>