Re: [PATCH v2 12/12] [UNTESTED] riscv: dts: starfive: beaglev-starlight: Enable gmac

From: Emil Renner Berthing
Date: Tue Nov 28 2023 - 07:08:27 EST


Cristian Ciocaltea wrote:
> On 11/26/23 23:10, Emil Renner Berthing wrote:
> > Cristian Ciocaltea wrote:
> >> The BeagleV Starlight SBC uses a Microchip KSZ9031RNXCA PHY supporting
> >> RGMII-ID.
> >>
> >> TODO: Verify if manual adjustment of the RX internal delay is needed. If
> >> yes, add the mdio & phy sub-nodes.
> >
> > Sorry for being late here. I've tested that removing the mdio and phy nodes on
> > the the Starlight board works fine, but the rx-internal-delay-ps = <900>
> > property not needed on any of my VisionFive V1 boards either.
>
> No problem, thanks a lot for taking the time to help with the testing!
>
> > So I wonder why you need that on your board
>
> I noticed you have a patch 70ca054e82b5 ("net: phy: motorcomm: Disable
> rgmii rx delay") in your tree, hence I you please confirm the tests were
> done with that commit reverted?
>
> > Also in the driver patch you add support for phy-mode = "rgmii-txid", but here
> > you still set it to "rgmii-id", so which is it?
>
> Please try with "rgmii-id" first. I added "rgmii-txid" to have a
> fallback solution in case the former cannot be used.

Ah, I see. Sorry I should have read up on the whole thread. Yes, the Starlight
board with the Microchip phy works with "rgmii-id" as is. And you're right,
with "rgmii-id" my VF1 needs the rx-internal-delay-ps = <900> property too.

>
> > You've alse removed the phy reset gpio on the Starlight board:
> >
> > snps,reset-gpios = <&gpio 63 GPIO_ACTIVE_LOW>
> >
> > Why?
>
> I missed this in v1 as the gmac handling was done exclusively in
> jh7100-common. Thanks for noticing!
>
> >>
> >> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxxxxxx>
> >> ---
> >> arch/riscv/boot/dts/starfive/jh7100-beaglev-starlight.dts | 5 +++++
> >> 1 file changed, 5 insertions(+)
> >>
> >> diff --git a/arch/riscv/boot/dts/starfive/jh7100-beaglev-starlight.dts b/arch/riscv/boot/dts/starfive/jh7100-beaglev-starlight.dts
> >> index 7cda3a89020a..d3f4c99d98da 100644
> >> --- a/arch/riscv/boot/dts/starfive/jh7100-beaglev-starlight.dts
> >> +++ b/arch/riscv/boot/dts/starfive/jh7100-beaglev-starlight.dts
> >> @@ -11,3 +11,8 @@ / {
> >> model = "BeagleV Starlight Beta";
> >> compatible = "beagle,beaglev-starlight-jh7100-r0", "starfive,jh7100";
> >> };
> >> +
> >> +&gmac {
> >> + phy-mode = "rgmii-id";
> >> + status = "okay";
> >> +};
> >
> > Lastly the phy-mode and status are the same for the VF1 and Starlight boards,
> > so why can't these be set in the jh7100-common.dtsi?
>
> I wasn't sure "rgmii-id" can be used for both boards and I didn't want
> to unconditionally enable gmac on Starlight before getting a
> confirmation that this actually works.
>
> If there is no way to make it working with "rgmii-id" (w/ or w/o
> adjusting rx-internal-delay-ps), than we should switch to "rgmii-txid".

Yeah, I don't exactly know the difference, but both boards seem to work fine
with "rgmii-id", so if that is somehow better and/or more correct let's just go
with that.

Thanks!
/Emil

>
> Thanks,
> Cristian