Re: MT7621 SoC Traffic Won't Flow on RGMII2 Bus/2nd GMAC

From: "Arınç ÜNAL" <arinc.unal@arinc9.com>
To: Andrew Lunn <andrew@lunn.ch>
Cc: "DENG Qingfang" <dqfext@gmail.com>,
	"Luiz Angelo Daros de Luca" <luizluca@gmail.com>,
	"Matthias Brugger" <matthias.bgg@gmail.com>,
	"John Crispin" <john@phrozen.org>,
	"Siddhant Gupta" <siddhantgupta416@gmail.com>,
	"Ilya Lipnitskiy" <ilya.lipnitskiy@gmail.com>,
	"Sergio Paracuellos" <sergio.paracuellos@gmail.com>,
	"Felix Fietkau" <nbd@nbd.name>,
	"Sean Wang" <sean.wang@mediatek.com>,
	"Mark Lee" <Mark-MC.Lee@mediatek.com>,
	"Russell King" <linux@armlinux.org.uk>,
	"Jakub Kicinski" <kuba@kernel.org>,
	"David Miller" <davem@davemloft.net>,
	"René van Dorst" <opensource@vdorst.com>,
	"moderated list:ARM/Mediatek SoC support"
	<linux-mediatek@lists.infradead.org>,
	netdev <netdev@vger.kernel.org>,
	linux-mips@vger.kernel.org,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
	<devicetree@vger.kernel.org>,
	openwrt-devel@lists.openwrt.org, erkin.bozoglu@xeront.com
Subject: Re: MT7621 SoC Traffic Won't Flow on RGMII2 Bus/2nd GMAC
Date: Sun, 23 Jan 2022 20:48:21 +0300	[thread overview]
Message-ID: <1c100b5b-1ea2-cb66-96e0-d0127b50f1a2@arinc9.com> (raw)
In-Reply-To: <Ye1zwIFUa5LPQbQm@lunn.ch>

On 23/01/2022 18:26, Andrew Lunn wrote:
> On Sun, Jan 23, 2022 at 11:33:04AM +0300, Arınç ÜNAL wrote:
>> Hey Deng,
>>
>> On 23/01/2022 09:51, DENG Qingfang wrote:
>>> Hi,
>>>
>>> Do you set the ethernet pinmux correctly?
>>>
>>> &ethernet {
>>>       pinctrl-names = "default";
>>>       pinctrl-0 = <&rgmii1_pins &rgmii2_pins &mdio_pins>;
>>> };
>>
>> This fixed it! We did have &rgmii2_pins on the gmac1 node (it was originally
>> on external_phy) so we never thought to investigate the pinctrl
>> configuration further! Turns out &rgmii2_pins needs to be defined on the
>> ethernet node instead.
> 
> PHYs are generally external, so pinmux on them makes no sense. PHYs in
> DT are not devices in the usual sense, so i don't think the driver
> core will handle pinmux for them, even if you did list them.
> 
> This could be interesting for the DT compliance checker. Ideally we
> want it to warn if it finds a pinmux configuration in a PHY node.

I don't see any warnings about it:

$ cpp -nostdinc -I include -I arch -undef -x assembler-with-cpp 
drivers/staging/mt7621-dts/mt7621.dtsi mt7621.dtsi.preprocessed
$ dtc -I dts -O dtb -p 0x1000 mt7621.dtsi.preprocessed -o mt7621.dtb
drivers/staging/mt7621-dts/mt7621.dtsi:28.21-33.4: Warning 
(unit_address_vs_reg): /cpuintc@0: node has a unit name, but no reg property
drivers/staging/mt7621-dts/mt7621.dtsi:40.34-47.6: Warning 
(unit_address_vs_reg): /fixedregulator@0: node has a unit name, but no 
reg property
drivers/staging/mt7621-dts/mt7621.dtsi:49.39-56.4: Warning 
(unit_address_vs_reg): /fixedregulator@1: node has a unit name, but no 
reg property
drivers/staging/mt7621-dts/mt7621.dtsi:410.11-449.7: Warning 
(unit_address_vs_reg): /ethernet@1e100000/mdio-bus/switch0@0/ports: node 
has a reg or ranges property, but no unit name
drivers/staging/mt7621-dts/mt7621.dtsi:28.21-33.4: Warning 
(unique_unit_address): /cpuintc@0: duplicate unit-address (also used in 
node /fixedregulator@0)

> 
> It also sounds like you had them somewhere else wrong?

Yes, it was under the phy_external node:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/staging/mt7621-dts/mt7621.dtsi#n350

I had put it under gmac1 node instead since we didn't enable the 
phy_external node.

Arınç