Re: [PATCH v2 10/11] ARM: dts: stm32: add ethernet1 and ethernet2 for STM32MP135F-DK board

[Alexandre TORGUE <alexandre.torgue@xxxxxxxxxxx>]

Hi Marek

On 4/26/24 17:44, Marek Vasut wrote:
> On 4/26/24 2:57 PM, Christophe Roullier wrote:
> > Add dual Ethernet:
> > -Ethernet1: RMII with crystal
> > -Ethernet2: RMII without crystal
> > PHYs used are SMSC (LAN8742A)
> >
> > With Ethernet1, we can performed WoL from PHY instead of GMAC point
> > of view.
> > (in this case IRQ for WoL is managed as wakeup pin and configured
> > in OS secure).
>
> How does the Linux PHY driver process such a PHY IRQ ?
>
> Or is Linux unaware of the PHY IRQ ? Doesn't that cause issues ?

In this case, we want to have an example to wakeup the system from 
Standby low power mode (VDDCPU and VDD_CORE off) thanks to a magic 
packet detected by the PHY. The PHY then assert his interrupt output signal.
On MP13 DK platform, this PHY signal is connected to a specific GPIO
aka "Wakeup pins" (only 6 wakeup pins an MP13). Those specific GPIOs are 
handled by the PWR peripheral which is controlled by the secure OS.

On WoL packet, the Secure OS catches the PHY interrupt and uses 
asynchronous notification mechanism to warn Linux (on our platform we 
use a PPI). On Linux side, Optee core driver creates an irq 
domain/irqchip triggered on the asynchronous notification. Each device 
which use a wakeup pin need then to request an IRQ on this "Optee irq 
domain".

This OPTEE irq domain will be pushed soon.

cheers
Alex

> > diff --git a/arch/arm/boot/dts/st/stm32mp135f-dk.dts 
> > b/arch/arm/boot/dts/st/stm32mp135f-dk.dts
> > index 567e53ad285f..3b8eb0ab9ab9 100644
> > --- a/arch/arm/boot/dts/st/stm32mp135f-dk.dts
> > +++ b/arch/arm/boot/dts/st/stm32mp135f-dk.dts
> > @@ -19,6 +19,8 @@ / {
> >       compatible = "st,stm32mp135f-dk", "st,stm32mp135";
> >       aliases {
> > +        ethernet0 = &ethernet1;
> > +        ethernet1 = &ethernet2;
> >           serial0 = &uart4;
> >           serial1 = &usart1;
> >           serial2 = &uart8;
> > @@ -141,6 +143,52 @@ &cryp {
> >       status = "okay";
> >   };
> > +&ethernet1 {
> > +    status = "okay";
> > +    pinctrl-0 = <&eth1_rmii_pins_a>;
> > +    pinctrl-1 = <&eth1_rmii_sleep_pins_a>;
> > +    pinctrl-names = "default", "sleep";
> > +    phy-mode = "rmii";
> > +    max-speed = <100>;
> > +    phy-handle = <&phy0_eth1>;
>
> Keep the list sorted please (is the max-speed even needed? if not, drop it)
>
> > +    mdio {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +        compatible = "snps,dwmac-mdio";
> > +
> > +        phy0_eth1: ethernet-phy@0 {
> > +            compatible = "ethernet-phy-id0007.c131";
> > +            reset-gpios =  <&mcp23017 9 GPIO_ACTIVE_LOW>;
> > +            reg = <0>;
> > +            wakeup-source;
> > +        };
> > +    };
> > +};
> > +
> > +&ethernet2 {
> > +    status = "okay";
> > +    pinctrl-0 = <&eth2_rmii_pins_a>;
> > +    pinctrl-1 = <&eth2_rmii_sleep_pins_a>;
> > +    pinctrl-names = "default", "sleep";
> > +    phy-mode = "rmii";
> > +    max-speed = <100>;
> > +    phy-handle = <&phy0_eth2>;
> > +    st,ext-phyclk;
> > +    phy-supply = <&scmi_v3v3_sw>;
>
> Sort please
>
> [...]