[U-Boot] [PATCH v2 12/23] sunxi: provide default DRAM config for sun50i in Kconfig

[Andre Przywara]

Hi,

On 06/12/16 10:56, Maxime Ripard wrote:
> On Mon, Dec 05, 2016 at 01:52:19AM +0000, Andre Przywara wrote:
>> To avoid enumerating the very same DRAM values in defconfig files
>> for each and every Allwinner A64 board out there, let's put some sane
>> default values in the Kconfig file.
>> Boards with different needs can override them at any time.
> 
> Did you check other boards to see what their values were before
> calling it a default?

I sampled all the boards (two ;-) I have access to and got a 100%
coverage ;-)
As far as I know, this 672 MHz seems to be an Allwinner recommendation,
though it needs to be worked out how stable this is under load.
I have no idea if the ZQ value is similarly common.

If you have any other data, I am all ears and happy to use a different
safe default if this is the intention.
But we could use a "most common value" approach here to avoid pointless
defconfig entries with the same value for lots of boards, so even if
there are board with can't do 672 MHz, for instance, we still put it in
Kconfig and let that one board override it.

Cheers,
Andre.