[U-Boot] [PATCH v1 2/2] arm: mvebu: Define NAND interface pins for A-38x

[Chris Packham]

On Tue, Aug 23, 2016 at 6:57 PM, Stefan Roese <sr at denx.de> wrote:
> Hi Chris,
>
> On 22.08.2016 02:38, Chris Packham wrote:
>>
>> From: Chris Packham <chris.packham at alliedtelesis.co.nz>
>>
>> Add pin control settings for the NAND flash interface. This interface
>> is multiplexed with the device bus interface to the function is "dev"
>> not "nand" as one might expect.
>>
>> Signed-off-by: Chris Packham <chris.packham at alliedtelesis.co.nz>
>> Cc: Luka Perkov <luka.perkov at sartura.hr>
>> Cc: Dirk Eibach <eibach at gdsys.de>
>> ---
>> I don't think this is strictly necessary. A quick scan of boards that
>> use this family of processor all seem to set their MPP configurations
>> manually.
>
>
> Correct. Unfortunately we don't have a pin-ctrl driver for AXP / A38x
> in U-Boot yet. Such a driver would be very welcome though. ;)
>
>> Another issue is that technically on the Armada-385 there are 4 possible
>> CE pins. The board I'm looking at happens to use CE#0 (mpp25) but mpp26,
>> mpp27 and mpp6 are all potentially available. I guess if any boards
>> actually use them they can add them to their pin specification. At the
>> very least such boards would need to update the num-cs property anyway.
>
>
> How is this handled in the kernel?

I haven't seen anything in the kernel yet that uses these chip selects.

> I would very much like to see
> these changes in the dts in sync with the kernel as much as
> possible. Does the kernel also use "dev" instead of "nand" here?

Yes I based this on
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/armada-39x.dtsi
I haven't got round to porting the kernel to my board so I imagine a
similar change will be required to armada-38x.dtsi in the kernel.

>
> Thanks,
> Stefan