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→ Alternately, patch in SGMII fixed link AR mentioned above can be used (especially if there is no PHY) with "is-internal-pcspma" property and a fixed link node. In this case, both Linux SW and PCS block do not attempt autoneg and the link status in PCS_status register will always report link up.

Pointers on PHY reset via GPIO

→ For boards which require a PHY reset via GPIO, please see the generic framework provisions here: https://github.com/Xilinx/linux-xlnx/blob/master/Documentation/devicetree/bindings/net/ethernet-phy.yaml#L141

This can be used for multiple PHYs with independent GPIO resets as well.

→ If reset is required before PHY detection, please see the MDIO bus provision here:  https://github.com/Xilinx/linux-xlnx/blob/master/Documentation/devicetree/bindings/net/mdio.yaml#L30

→ When using PHY reset via GPIO, please check manufacturer specific datasheet for the reset polarity, reset assert duration and post de-assert delay for PHY to be functional. These values can then be passed to PHY and MDIO framework via Devicetree documentation above.

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