[U-Boot-Users] [PATCH0/2] Re-do the patch for adding DO_SYNC in flash_write_cmd

Tolunay Orkun listmember at orkun.us
Sat Feb 10 08:57:36 CET 2007


Stefan Roese wrote:
> On Saturday 10 February 2007 08:23, Tolunay Orkun wrote:
>>>> We need to define SYNC as asm("sync;").
>>> Or, to be sure, ""sync;isync"
>> OK.
> 
> I would not do this. Please let a "sync" instruction _not_ do a "isync" too. 
 > There will be times when you explicitly _don't_ what this.

Could you give a specific example.

There is also "eieio" and "msync" to consider though these usually map 
to former two (or vice versa).

>>> Where is the problem? Which code includes include/ppc_asm.tmpl ?  Why
>>> cannot  we  have  the  same  definition  once  for  C  and  again for
>>> assembler?
>> I agree, I think we can define the equivalent one in a C header file
>>
>> #define SYNC asm("sync; isync;")
>>
>> I am not sure if the assembler one is ever included in the C code.
> 
> Why not use
> 
> #define sync()  __asm__ __volatile__ ("sync" : : : "memory");
> 
> from include/asm-ppc/io.h? This seems to be exactly what we need.
> 

I would rather prefer an uppercase SYNC since it is a macro but whatever 
style you guys choose is OK with me.

Please you and Wolfgang decide on this matter. I do not want to confuse 
Haiying with conflicting messages.

Tolunay




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