[U-Boot] mkconfig "arch" link generation

[Matteo Facchinetti <matteo.facchinetti@sirius-es.it>]

Stefano Babic wrote:
> Matteo Facchinetti wrote:
>   
>> Hi,
>>
>>     
>
> Hi Matteo,
>
>   
Hi Stefano,
>> I'm updating my uboot to mainline and I have a question about a link 
>> generate from mkconfig (with mpc5121_config).
>> Follwing link in "include/asm", I found a link named "arch" genarated by 
>> mkconfig.
>> This is broken so point to "arch-mpc512x" instead of 
>> "arch/powerpc/cpu/mpc512x".
>>     
>
> Yes, the link is broken. However, all boards in the mainline using the
> MPC512x are compiled clean. This is because asm-offsets.h is included
> only by arch/powerpc/cpu/mpc512x/start.S with "#include "asm-offsets.h",
> and the compiler search for the file in the same directory of start.S
> and can find it.
> The link is not required to compile the 512x boards supported currently
> by u-boot, but it must be set for the ARM architecture. Under the
> kernel, asm-offsets.h is auto-generated (I know, this is the best solution).
>
> However, why do you need this file ? It should be required only by low
> level initialization in assembly, as it is done by start.S. After that,
> it is required in u-boot to access to registers/peripherals via C
> structures and not using offsets.
>   
Yes, you're rigth,
but I'm tring to write nand_spl driver for add nand boot support for my 
TWR-MPC5125 evaluation board.
In first step I take what I need from LTIB (freescale) and  then I 
adjust the code for uboot mainline.
The part takes from LTIB of 2k first stage nandboot code uses directly 
SRAMBAR and SWCRR defines.

Now, I suppose, correct develop is to use the common c code in nand_spl 
directory and eventually customizing for my board unless use 
"include/asm/arch/..." for powerpc arch.
Is it true?

>> Result is "#include <asm/arch/asm-offsets.h>" or similar are be broken.
>>
>> How is the correct way to modify mkconfig?
>>     
>
> Probably not setting the link for powerpc, because it is not required.
>
> Regards,
> Stefano Babic
>
>