[U-Boot] litesom.c: Board stuff in SOC ?

[Marcin Niestroj]

Hi Stefano,

On 18.05.2017 16:28, Stefano Babic wrote:
> Hi Marcin,
> 
> even if it was already merged (and maybe I am guilty of it because I
> have not noted before), it is completely crazy that a board is stored
> inside the SOC directory. The litesom board is in fact in
> ./arch/arm/cpu/armv7/mx6/litesom.c, and there is nothing that justify
> this. The code has just board related stuff and nothing common for all SOC.

litesom is not a board, but a SOM. It has only RAM and eMMC memory
included with the processor. litesom cannot work on it's own. It needs
to be part of some board. An example board is liteboard, which support
is included in board/grinn/liteboard/. Please visit [2] to visualize
what the litesom device is.

The idea about creating a separate file in arch/arm/cpu/armv7/mx6/
was to be able to reuse code when new boards, that use litesom
as it's core, will be added. And these boards need not to be
manufactured or designed by Grinn. So if some other vendor wants
to add support for it's board (which will be based on litesom),
the code to initialize RAM and eMMC can be reused. When litesom
code would be part of board/grinn/ directory, then other vendors
could not easily add support for their boards without copying
litesom sources.

[2] http://grinn-global.com/litesom/

> 
> I just took again the commit and I see:
> 
> Moving arch/arm/mach-litesom/ to arch/arm/cpu/armv7/mx6/ was requested
> in [1] during discussion of chiliSOM support patches.
> 
> [1] http://lists.denx.de/pipermail/u-boot/2017-January/279137.html
> 
> 
> But [1] has nothing to do with the context.  I will tend to revert this
> patch and wait for an appropriate patch that add support for the board
> just like all other boards in U-Boot - as it is currently, it is wrong.

Link [1] was a discussion of adding chilisom support into u-boot.
The idea was the same - allow to reuse SOM code for vendors creating
their own board based on our SOMs.

Regards,
Marcin

> 
> Regards,
> Stefano
> 

-- 
Marcin Niestroj