[U-Boot] [RFC PATCH] arm, davinci: Remove board specific code from da850_lowlevel.c

[Heiko Schocher <hs@denx.de>]

Hello Christian,

Christian Riesch wrote:
> Hello Heiko,
> Thank you for your reply!
> 
> On Wed, Nov 9, 2011 at 6:37 AM, Heiko Schocher <hs@denx.de> wrote:
>> Hello Christian,
>>
>> Christian Riesch wrote:
>>> Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
>>> ---
>>>
>>> Hello Heiko,
>>>
>>> On my board I cannot use your code in arch_cpu_init() in da850_lowlevel.c
>>> since I have different versions of my board with different input
>>> clock frequencies. Here u-boot should first determine the board
>>> revision number and then configure the SoC accordingly. Therefore I would
>>> like to move all board-specific parts (and PLL and memory configuration is
>>> board-specific since it depends on the memory chips and oscillators
>>> deployed on the board) to board_early_init_f which is called right after
>>> arch_cpu_init() and keep only a few initializiation steps in arch_cpu_init().
>> Ok, if you have other needs on your board we must change something.
>> But I want to prevent, that all the code you remove in your patch is
>> moved to board code, so all boards must (copy?) it. Instead you should
>> move it to a weak function, which you can replace for your specific
>> needs. (I thought the code was common enough ...)
>>
>> What do you think?
> 
> That's fine for me, I tried it now with
> 
> __attribute__((weak))  int arch_cpu_init(void)
> 
> and added my own arch_cpu_init() to my board specific file.
> 
> Of course I had to add all those CONFIG_SYS_DA850_PINMUXn with dummy
> values to my board config file to make it build... I don't like those
> defines because the values are difficult to read and we already have

Why? They are in sync with the doc ...

> code for pinmuxing in board/davinci/common/davinci_pinmux.c so it is
> duplicate code. Couldn't we move this davinci_pinmux.c to
> arch/arm/cpu/arm926ejs/davinci and use it instead? What do you think?

Hmm.. if you use the http://www-s.ti.com/sc/techlit/spraba2.zip
utility from ti, you exactly get the values for the defines ...
so I prefered to go this way, but have no real objections against
using the code from board/davinci/common/davinci_pinmux.c
(Of course, it should be moved to arch/arm/cpu/arm926ejs/davinci)

added Sandeep to cc. Sandeep, what do you think?

> I'll submit a patch for adding the weak attribute.

Thanks!

bye,
Heiko
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