Re: [PATCH RFC] ARM: dts: add support for Turris Omnia

[tomas.hlavacek@nic.cz]

Hi Uwe!

On Sun, Nov 20, 2016 at 9:30 PM, Uwe Kleine-König 
<uwe@kleine-koenig.org> wrote:
> Hello Tomas,
> 
> On Sat, Nov 19, 2016 at 09:09:07PM +0100, tomas.hlavacek@nic.cz wrote:
>>  On Mon, Nov 14, 2016 at 9:28 PM, Andrew Lunn <andrew@lunn.ch> wrote:
>>  > Interrupts don't seem to work very well with the nxp,pca9538. 
>> Which
>>  > is probably why it is disabled by default.
>> 
>>  I was thinking about this issue and I can remember that there was 
>> an earlier
>>  prototype that had a shared interrupt line from PHY (88E1514) and 
>> from the
>>  PCA9538. In this case we needed to specifically disable the 
>> interrupt of the
>>  PHY to release the interrupt line (which needed a hack into PHY 
>> driver
>>  code). The IRQ from PHY is connected as an ordinary input to 
>> PCA9538 in
>>  later board prototype. And the same holds for the production 
>> version.
> 
> That would explain why I see an "irq but nobody cared" message when
> booting the original system.
> 
> This isn't the problem I meant though. When adding interrupt-parent =
> <&pcawan>; interrupts = <7 IRQ_TYPE_LEVEL_LOW>; to the phy node I get 
> an
> error saying that there is no irq domain associated with this device.
> 
>>  Do you have CZ11NIC13 or older board revision?
> 
> CZ11NIC12 is indicated on my board.

:-( Well, this board version has wrongly matched length of some 
differential pairs, IRQ from 88E1514 is connected differently, there 
are slight differences in power supplies and (if I am not mistaken) 
something changed in RTC support circuitry. It looks like a huge 
mistake on our side.

Anyway I took your patch and tried few things:
- clean up comments
- add pca9538 interrupt-controller
- remove rtc disable (WFM with CZ11NIC13, which is the production board)
- add MBUS mem regions for CESA
- add IRQ for 88E1514 PHY - and there is a problem:

It seems that libphy is probed before pca9538 and we end up with:
[    4.217550] libphy: orion_mdio_bus: probed
[    4.221777] irq: no irq domain found for 
/soc/internal-regs/i2c@11000/i2cmux@70/i2c@7/gpio@71 !

Any clue where to look in order to defer probing libphy or at least 
orion_mdio_bus?

I'll post my version of the patch without the PHY IRQ (therefore 
polling will kick in).

Thanks,
Tomas