Re: [PATCH net-next 2/3] net: dsa: realtek: Add support for use of an optional mdio node

[Jonas Karlman <jonas@kwiboo.se>]

Hi Andrew,

On 7/28/2025 5:40 PM, Andrew Lunn wrote:
>> When it comes to having the switch being described as an interrupt
>> controller in the DT is also very wrong, the switch only consume a
>> single HW interrupt. The fact that the driver creates virtual irq for
>> each port is purely a software construct and is not something that
>> should be reflected in the DT.
> 
> I think that is not always clear cut. Switches can be considered SoC
> of their own. They have multiple hardware blocks, which can be
> described independent, just like a traditional SoC and its .dtsi
> file. The switch blocks can then be connected together in the same way
> SoCs are.

I guess you are correct, thanks for clarifying this :-)

> I've not looked at this particular switch driver, but the Marvell
> switches have a similar single interrupt output pin connected to the
> host SoC. Within the switch, there are at least two cascaded interrupt
> controllers. We implement standard Linux interrupt controllers for
> these. That allows us to use standard DT properties to link the
> internal PHY interrupts to these interrupt controllers.

Makes sense, I will describe the phy interrupts of the switch in a v2.

Regards,
Jonas

> 
> 	 Andrew