[U-Boot] [PATCH] at91: board specific lowlevel_init.S

[Jean-Christophe PLAGNIOL-VILLARD]

On 15:07 Wed 22 Oct     , Ilko Iliev wrote:
> Jean-Christophe PLAGNIOL-VILLARD wrote:
>> On 13:12 Wed 22 Oct     , Ilko Iliev wrote:
>>   
>>> Dear Mr. Denk,
>>>
>>>     
>>>> Dear Ilko Iliev,
>>>>
>>>> In message <48FDFCA0.4090608 at ronetix.at> you wrote:
>>>>         
>>>>>> Maybe instead of adding mor #ifdef'ery here, we can turn
>>>>>> lowlevel_init() into a "weak" function that can be redefined by board
>>>>>> specific code?
>>>>>>                 
>>>>> The lowlevel_init() is an assembler function called from another  
>>>>> assembler function and the attribute .weak doesn't work.
>>>>>             
>>>> What do you mean by "attribute .weak doesn't work" ?
>>>>
>>>>         
>>>>> There are no assembler file in the U-BOOT tree which use weak functions.
>>>>> Do you know how can I make an assembler function weak?
>>>>>             
>>>> Well, if you don't know, then don't ask me, ask your compiler - he
>>>> knows how to do this.
>>>>
>>>> For example, common/cmd_boot.c has this code snippet right at the
>>>> beginning:
>>>>
>>>>  30
>>>>  31 /* Allow ports to override the default behavior */
>>>>  32 __attribute__((weak))
>>>>  33 unsigned long do_go_exec (ulong (*entry)(int, char *[]), int argc, char *argv[])
>>>>  34 {
>>>>  35         return entry (argc, argv);
>>>>  36 }
>>>>
>>>> Compile this with -S option, and you get this:
>>>>
>>>>  12 .Ltext0:
>>>>  13         .align 2
>>>>  14         .weak   do_go_exec
>>>>  15         .type   do_go_exec, @function
>>>>  16 do_go_exec:
>>>>  17 .LFB87:
>>>>  18         .file 1 "cmd_boot.c"
>>>>  19         .loc 1 34 0
>>>>  20 .LVL0:
>>>>  21         mflr 0
>>>>  22 .LCFI0:
>>>>  23         stwu 1,-16(1)
>>>> ...
>>>>
>>>>
>>>> So to me it seems as if the attribute .weak is supposed to work just fine.
>>>>
>>>> What exactly is not working for you?
>>>>
>>>>         
>>> With ".weak lowlevel_init" the function is marked as weak (I can see  
>>> this in the ELF file) but it is not overwritten from the another  
>>> lowlevel_init().
>>>     
>> try

>>   
> I tried and the result is:
> lowlevel_init.S:32: Error: junk at end of line, first unrecognized  
> character is `='
>
	sorry try this

	.global __default_lowlevel_init
		.....
	.weak	lowlevel_init
	.set	lowlevel_init,__default_lowlevel_init

	after in the other asm
	.global lowlevel_init
		.......

Best Regards,
J.