Message-ID: <7e219aef-88a0-4184-9553-30dcbc8dbd79@lunn.ch>
Date: Tue, 7 Oct 2025 16:57:32 +0200
From: Andrew Lunn <andrew@...n.ch>
To: jjm2473 <jjm2473@...il.com>
Cc: robh@...nel.org, krzk+dt@...nel.org, conor+dt@...nel.org,
	heiko@...ech.de, quentin.schulz@...rry.de,
	kever.yang@...k-chips.com, naoki@...xa.com, honyuenkwun@...il.com,
	inindev@...il.com, ivan8215145640@...il.com,
	neil.armstrong@...aro.org, mani@...nel.org, dsimic@...jaro.org,
	pbrobinson@...il.com, alchark@...il.com, didi.debian@...ow.org,
	jbx6244@...il.com, devicetree@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-rockchip@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 3/3] arm64: dts: rockchip: add LinkEase EasePi R1

On Tue, Oct 07, 2025 at 10:32:26PM +0800, jjm2473 wrote:
> Andrew Lunn <andrew@...n.ch> 于2025年10月6日周一 23:51写道：
> >
> > > +&gmac0 {
> > > +     phy-mode = "rgmii";
> >
> > Did i really miss this patch series in its earlier version, or did you
> > ignore me?
> >
> > https://elixir.bootlin.com/linux/v6.15/source/Documentation/devicetree/bindings/net/ethernet-controller.yaml#L287
> >
> > > +     tx_delay = <0x3c>;
> > > +     rx_delay = <0x2f>;
> >
> > Please change it to rgmii-id, and smaller tx/rx_delay values. Or show
> > us the schematics which clearly show extra long clock lines.
> >
> > > +/* Micro SD card slot is not mounted */
> > > +&sdmmc0 {
> > > +     max-frequency = <150000000>;
> > > +     no-sdio;
> > > +     no-mmc;
> > > +     bus-width = <4>;
> > > +     cap-mmc-highspeed;
> > > +     cap-sd-highspeed;
> > > +     disable-wp;
> > > +     pinctrl-names = "default";
> > > +     pinctrl-0 = <&sdmmc0_bus4 &sdmmc0_clk &sdmmc0_cmd &sdmmc0_det>;
> > > +     vmmc-supply = <&vcc3v3_sd>;
> > > +     vqmmc-supply = <&vccio_sd>;
> > > +     status = "disabled";
> > > +};
> > > +
> > > +/* Wifi module is not mounted */
> > > +&sdmmc2 {
> >
> > What do you mean by "not mounted"?
> >
> > Often you would say "not populated", to indicate the PCB has all the
> > tracks in place, but the chip has simply not been soldered in place.
> >
> > Or is there a connector here, and nothing plugged into the connector?
> >
> >    Andrew
> 
> Andrew:
>  Hello! I ran `./scripts/get_maintainer.pl
> patches-v4/v4-0003-arm64-dts-rockchip-add-LinkEase-EasePi-R1.patch`
> to get maintainer list, and got:
> ```
> Rob Herring <robh@...nel.org> (maintainer:OPEN FIRMWARE AND FLATTENED
> DEVICE TREE BINDINGS)
> Krzysztof Kozlowski <krzk+dt@...nel.org> (maintainer:OPEN FIRMWARE AND
> FLATTENED DEVICE TREE BINDINGS,commit_signer:3/41=7%)
> Conor Dooley <conor+dt@...nel.org> (maintainer:OPEN FIRMWARE AND
> FLATTENED DEVICE TREE BINDINGS)
> Heiko Stuebner <heiko@...ech.de> (maintainer:ARM/Rockchip SoC
> support,commit_signer:43/41=100%,authored:4/41=10%,added_lines:12/117=10%,commit_signer:5/6=83%)
> Quentin Schulz <quentin.schulz@...rry.de>
> (commit_signer:10/41=24%,authored:8/41=20%,added_lines:63/117=54%)
> Dragan Simic <dsimic@...jaro.org> (commit_signer:5/41=12%,commit_signer:1/6=17%)
> FUKAUMI Naoki <naoki@...xa.com>
> (commit_signer:3/41=7%,authored:3/41=7%,removed_lines:1/1=100%)
> Peter Robinson <pbrobinson@...il.com>
> (added_lines:9/117=8%,commit_signer:1/6=17%,authored:1/6=17%)
> Alexey Charkov <alchark@...il.com> (added_lines:6/117=5%)
> Diederik de Haas <didi.debian@...ow.org>
> (commit_signer:4/6=67%,authored:3/6=50%)
> Liangbin Lian <jjm2473@...il.com> (commit_signer:1/6=17%,authored:1/6=17%)
> Johan Jonker <jbx6244@...il.com> (authored:1/6=17%)
> devicetree@...r.kernel.org (open list:OPEN FIRMWARE AND FLATTENED
> DEVICE TREE BINDINGS)
> linux-arm-kernel@...ts.infradead.org (moderated list:ARM/Rockchip SoC support)
> linux-rockchip@...ts.infradead.org (open list:ARM/Rockchip SoC support)
> linux-kernel@...r.kernel.org (open list)
> ```
> your email address is not listed above.

What i eventually found is that you posted v3 separately, and then
threaded v4 to v2, which makes no sense.

Please always start a new thread for each patchset.

> > What do you mean by "not mounted"?
> >
> > Often you would say "not populated", to indicate the PCB has all the
> > tracks in place, but the chip has simply not been soldered in place.
> >
> > Or is there a connector here, and nothing plugged into the connector?
> 
> The chip/slot has not been soldered. So here should be "not
> populated", forgive my poor English.

Thanks for the clarification. I'm not sure it is worth adding these DT
properties. When a new board is produced which does populate these
devices, you are going to need a new .dts file. So you can put the
properties into that new file.

> 
> > Please change it to rgmii-id, and smaller tx/rx_delay values. Or show
> > us the schematics which clearly show extra long clock lines.
> 
> In fact, the RTL8211F's RXDLY and TXDLY signals are both pulled low,
> just like the Banana Pi BPI-R2 Pro, so the configuration is also referenced:
> https://elixir.bootlin.com/linux/v6.15/source/arch/arm64/boot/dts/rockchip/rk3568-bpi-r2-pro.dts#L237

Pull low makes no difference to the 2ns RGMII delays.

> The tx_delay and rx_delay values were obtained using Rockchip's
> automatic scanning tool:
> https://github.com/istoreos/istoreos/blob/54746dfdb5bd34d1f281cf41d1d1620d0c3ee686/target/linux/rockchip/files/drivers/net/ethernet/stmicro/stmmac/dwmac-rk-tool.c
> https://gitlab.com/firefly-linux/docs/-/blob/rk356x/firefly/Common/GMAC/Rockchip_Developer_Guide_Linux_GMAC_RGMII_Delayline_EN.pdf
> https://github.com/axlrose/rkdocs/blob/main/Common/GMAC/Rockchip_Developer_Guide_Linux_GMAC_RGMII_Delayline_EN.pdf

Vendors get things wrong, including this. 'rgmii' means the PCB adds
the 2ns delay. Nearly every Rockchip board follows Rockchip broken
vendor recommendations, and then i come along, point out how it is
wrong, and ask for it to be fixed, before being merged to Mainline.

	Andrew

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