Device tree changes for dual Ethernet port usage

[memaher]

Currently chasing down problems with the Ethernet ports on a custom board. One of the issues may be because I’ve got 2x Ethernet ports allocated but not necessarily the correct device tree setup for them.

I’ve followed the steps given in your application note (https://octavosystems.com/app_notes/ethernet-am335x-system-in-package/), with regards the phy-ID’s etc. However, something which isn’t clear is the allocation of the 2nd Ethernet device, given the mac{} statement only assigns the 1st set of pins, leaving the 2nd unconnected/unassigned (I’m referencing osd335x-sm.dtsi)

It’s a really stupid point, but I’m stumped on where to allocate the 2nd port! Code so far is below, any ideas?

thanks
Mat

——————-

&cpsw_emac0
{
phy_id = <&davinci_mdio>, <0>;
phy-mode = “mii”;
};

&cpsw_emac1
{
phy_id = <&davinci_mdio>, <1>;
phy-mode = “mii”;
};

&mac
{
slaves = <1>;
pinctrl-names = “default”;
pinctrl-0 = <&mii1_pins_default>;
status = “okay”;
};

&davinci_mdio
{
pinctrl-names = “default”;
pinctrl-0 = <&mymdio1_pins_default>;
status = “okay”;
};

mii1_pins_default: mii1_pins_default
{
pinctrl-single,pins = <
AM33XX_IOPAD(0x108, PIN_INPUT | MUX_MODE0) /* (H16) gmii1_col.gmii1_col */
AM33XX_IOPAD(0x10c, PIN_INPUT | MUX_MODE0) /* (H17) gmii1_crs.gmii1_crs */
AM33XX_IOPAD(0x110, PIN_INPUT | MUX_MODE0) /* (J15) gmii1_rxer.gmii1_rxer */
AM33XX_IOPAD(0x114, PIN_OUTPUT | MUX_MODE0) /* (J16) gmii1_txen.gmii1_txen */
AM33XX_IOPAD(0x118, PIN_INPUT | MUX_MODE0) /* (J17) gmii1_rxdv.gmii1_rxdv */
AM33XX_IOPAD(0x12c, PIN_INPUT | MUX_MODE0) /* (K18) gmii1_txclk.gmii1_txclk */
AM33XX_IOPAD(0x130, PIN_INPUT | MUX_MODE0) /* (L18) gmii1_rxclk.gmii1_rxclk */
AM33XX_IOPAD(0x128, PIN_OUTPUT | MUX_MODE0) /* (K17) gmii1_txd0.gmii1_txd0 */
AM33XX_IOPAD(0x124, PIN_OUTPUT | MUX_MODE0) /* (K16) gmii1_txd1.gmii1_txd1 */
AM33XX_IOPAD(0x120, PIN_OUTPUT | MUX_MODE0) /* (K15) gmii1_txd2.gmii1_txd2 */
AM33XX_IOPAD(0x11c, PIN_OUTPUT | MUX_MODE0) /* (J18) gmii1_txd3.gmii1_txd3 */
AM33XX_IOPAD(0x140, PIN_INPUT | MUX_MODE0) /* (M16) gmii1_rxd0.gmii1_rxd0 */
AM33XX_IOPAD(0x13c, PIN_INPUT | MUX_MODE0) /* (L15) gmii1_rxd1.gmii1_rxd1 */
AM33XX_IOPAD(0x138, PIN_INPUT | MUX_MODE0) /* (L16) gmii1_rxd2.gmii1_rxd2 */
AM33XX_IOPAD(0x134, PIN_INPUT | MUX_MODE0) /* (L17) gmii1_rxd3.gmii1_rxd3 */
>;
};

mii2_pins_default: mii2_pins_default
{
pinctrl-single,pins = <
AM33XX_IOPAD(0x78, PIN_INPUT | MUX_MODE1) /* (U18) gpmc_be1n.gmii2_col */
AM33XX_IOPAD(0x70, PIN_INPUT | MUX_MODE1) /* (T17) gpmc_wait0.gmii2_crs */
AM33XX_IOPAD(0x74, PIN_INPUT | MUX_MODE1) /* (U17) gpmc_wpn.gmii2_rxer */
AM33XX_IOPAD(0x40, PIN_OUTPUT | MUX_MODE1) /* (R13) gpmc_a0.gmii2_txen */
AM33XX_IOPAD(0x44, PIN_INPUT | MUX_MODE1) /* (V14) gpmc_a1.gmii2_rxdv */
AM33XX_IOPAD(0x58, PIN_INPUT | MUX_MODE1) /* (U15) gpmc_a6.gmii2_txclk */
AM33XX_IOPAD(0x5c, PIN_INPUT | MUX_MODE1) /* (T15) gpmc_a7.gmii2_rxclk */
AM33XX_IOPAD(0x54, PIN_OUTPUT | MUX_MODE1) /* (V15) gpmc_a5.gmii2_txd0 */
AM33XX_IOPAD(0x50, PIN_OUTPUT | MUX_MODE1) /* (R14) gpmc_a4.gmii2_txd1 */
AM33XX_IOPAD(0x4c, PIN_OUTPUT | MUX_MODE1) /* (T14) gpmc_a3.gmii2_txd2 */
AM33XX_IOPAD(0x48, PIN_OUTPUT | MUX_MODE1) /* (U14) gpmc_a2.gmii2_txd3 */
AM33XX_IOPAD(0x6c, PIN_INPUT | MUX_MODE1) /* (V17) gpmc_a11.gmii2_rxd0 */
AM33XX_IOPAD(0x68, PIN_INPUT | MUX_MODE1) /* (T16) gpmc_a10.gmii2_rxd1 */
AM33XX_IOPAD(0x64, PIN_INPUT | MUX_MODE1) /* (U16) gpmc_a9.gmii2_rxd2 */
AM33XX_IOPAD(0x60, PIN_INPUT | MUX_MODE1) /* (V16) gpmc_a8.gmii2_rxd3 */
>;
};

[Eshtaartha Basu]

Hello memaher,

In case of a dual ethernet design, the pin mux for both PHYs should be declared under the same phandle (&mii1n2_pins_default) instead of two separate ones.

AM335x Starter Kit reference design has Gigabit Dual Ethernet support (http://www.ti.com/tool/TMDSSK3358#technicaldocuments). It would be best if you use their device tree source file as a good functional reference while tweaking your own device tree. Their device tree source can be found here – https://github.com/beagleboard/devicetree-source/blob/master/arch/arm/boot/dts/am335x-evmsk.dts. Furthermore, don’t forget to set additional properties mentioned in point 6 under section 4 of our Ethernet app note (https://octavosystems.com/app_notes/ethernet-am335x-system-in-package/) that are critical for Dual Ethernet design. Keep in mind that if your PHY is different from what is present on AM335x Starter Kit, the Mux Mode for the pins may need to be suitably changed in the pin mux depending on the mode of communication your PHY supports (MII, GMII or RGMII).

[memaher]

Thanks Eshtaartha,

I’ve implemented the changes for dual ethernet as suggested but I think it highlights a more fundamental problem with my system! I’ll post in a new thread…

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