i.MX8QM uses separate MDIO interface cannot make 2nd ethernet work

[eric_lee1]

We are working on i.MX8QM custom board with two AR8035 Ethernet PHYs attached by separate MDIO interfaces (ETH0_MDC, ETH0_MDIO)(ETH1_MDC,ETH1_MDIO). The BSP we are working is 5.4.70. The device tree setting is as follows.

pinctrl_fec1: fec1grp {
fsl,pins = <
IMX8QM_COMP_CTL_GPIO_1V8_3V3_ENET_ENETB_PAD 0x000014a0
IMX8QM_ENET0_MDC_CONN_ENET0_MDC 0x06000020
IMX8QM_ENET0_MDIO_CONN_ENET0_MDIO 0x06000020
IMX8QM_ENET0_RGMII_TX_CTL_CONN_ENET0_RGMII_TX_CTL 0x06000020
IMX8QM_ENET0_RGMII_TXC_CONN_ENET0_RGMII_TXC 0x06000020
IMX8QM_ENET0_RGMII_TXD0_CONN_ENET0_RGMII_TXD0 0x06000020
IMX8QM_ENET0_RGMII_TXD1_CONN_ENET0_RGMII_TXD1 0x06000020
IMX8QM_ENET0_RGMII_TXD2_CONN_ENET0_RGMII_TXD2 0x06000020
IMX8QM_ENET0_RGMII_TXD3_CONN_ENET0_RGMII_TXD3 0x06000020
IMX8QM_ENET0_RGMII_RXC_CONN_ENET0_RGMII_RXC 0x06000020
IMX8QM_ENET0_RGMII_RX_CTL_CONN_ENET0_RGMII_RX_CTL 0x06000020
IMX8QM_ENET0_RGMII_RXD0_CONN_ENET0_RGMII_RXD0 0x06000020
IMX8QM_ENET0_RGMII_RXD1_CONN_ENET0_RGMII_RXD1 0x06000020
IMX8QM_ENET0_RGMII_RXD2_CONN_ENET0_RGMII_RXD2 0x06000020
IMX8QM_ENET0_RGMII_RXD3_CONN_ENET0_RGMII_RXD3 0x06000020
>;
};

pinctrl_fec2: fec2grp {
fsl,pins = <
IMX8QM_COMP_CTL_GPIO_1V8_3V3_ENET_ENETA_PAD 0x000014a0
IMX8QM_ENET1_MDC_CONN_ENET1_MDC 0x06000020
IMX8QM_ENET1_MDIO_CONN_ENET1_MDIO 0x06000020
IMX8QM_ENET1_RGMII_TX_CTL_CONN_ENET1_RGMII_TX_CTL 0x00000060
IMX8QM_ENET1_RGMII_TXC_CONN_ENET1_RGMII_TXC 0x00000060
IMX8QM_ENET1_RGMII_TXD0_CONN_ENET1_RGMII_TXD0 0x00000060
IMX8QM_ENET1_RGMII_TXD1_CONN_ENET1_RGMII_TXD1 0x00000060
IMX8QM_ENET1_RGMII_TXD2_CONN_ENET1_RGMII_TXD2 0x00000060
IMX8QM_ENET1_RGMII_TXD3_CONN_ENET1_RGMII_TXD3 0x00000060
IMX8QM_ENET1_RGMII_RXC_CONN_ENET1_RGMII_RXC 0x00000060
IMX8QM_ENET1_RGMII_RX_CTL_CONN_ENET1_RGMII_RX_CTL 0x00000060
IMX8QM_ENET1_RGMII_RXD0_CONN_ENET1_RGMII_RXD0 0x00000060
IMX8QM_ENET1_RGMII_RXD1_CONN_ENET1_RGMII_RXD1 0x00000060
IMX8QM_ENET1_RGMII_RXD2_CONN_ENET1_RGMII_RXD2 0x00000060
IMX8QM_ENET1_RGMII_RXD3_CONN_ENET1_RGMII_RXD3 0x00000060
>;
};

&fec1 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_fec1>;
phy-mode = "rgmii-txid";
phy-handle = <&ethphy0>;
fsl,magic-packet;
fsl,rgmii_rxc_dly;
status = "okay";

mdio {
compatible = "snps,dwmac-mdio";
#address-cells = <1>;
#size-cells = <0>;

ethphy0: ethernet-phy@6 {
compatible = "ethernet-phy-ieee802.3-c22";
reg = <6>;
at803x,eee-disabled;
at803x,vddio-1p8v;
};

};
};

&fec2 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_fec2>;
phy-mode = "rgmii-txid";
phy-handle = <&ethphy1>;
fsl,magic-packet;
fsl,rgmii_rxc_dly;
status = "okay";

mdio {
#address-cells = <1>;
#size-cells = <0>;

ethphy1: ethernet-phy@6 {
compatible = "ethernet-phy-ieee802.3-c22";
reg = <6>;
at803x,eee-disabled;
at803x,vddio-1p8v;
};
};
};

Only eth0 can work and eth1 complain about "fec 5b050000.ethernet eth1: Unable to connect to phy"

We knew that the mek uses a shared MDIO bus to implement two PHYs. My question is that could i.MX8QM uses separate MDIO to implement two ethernet PHYs? (We also refer the i.MX8MP EVK setting, but no licks.)

-Eric

[jimmychan]

FYI. This may help you

https://www.toradex.com/community/questions/55635/apalis-imx8qm-external-rgmii-interface-issue.html

[eric_lee1]

Could anyone reply If i.MX8QM can use separate MDIO (MDIO0 and MDIO1) to connect two Ethernet PHYs? It seems that only i.MX8MP and i.MX8DXL can do that. The common things in these two processors are the Ethernet pins are pinmuxed to EQOS. 

-Eric