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.. dtcompatible:: xlnx,gem
.. _dtbinding_xlnx_gem:

xlnx,gem
########

Vendor: :ref:`Xilinx <dt_vendor_xlnx>`

Description
***********



.. code-block:: none

   Xilinx GEM Ethernet controller

Properties
**********

.. tabs::

   .. group-tab:: Node specific properties

      Properties not inherited from the base binding file.

      .. list-table::
         :widths: 1 1 4
         :header-rows: 1

         * - Name
           - Type
           - Details

         * - ``clock-frequency``
           - ``int``
           - .. code-block:: none

                Specifies the base clock frequency from which the GEM's TX clock
                frequency will be derived using two dividers in the respective GEM's
                clock control register in the CRL_APB. The GEM's TX clock frequency
                is determined by the current link speed reported by the PHY, to
                which it will be adjusted at run-time. Therefore, the value of this
                item must be set to the clock frequency of the PLL supplying the
                respective GEM's TX clock - by default, this is the IO PLL.



             This property is **required**.

         * - ``mdc-divider``
           - ``int``
           - .. code-block:: none

                The MDC clock divider for the respective GEM. This is the divider
                applied to the LPD_LSBUS clock in order to derive MDIO interface
                clock driving communications with the attached PHY. Refer to the
                ZynqMP register documentation (ug1087), network_config (GEM) Register
                Description, bits [20:18] to determine the appropriate divider for
                the current target's LPD LSBUS clock frequency.



             This property is **required**.

         * - ``init-mdio-phy``
           - ``boolean``
           - .. code-block:: none

                Activates the management of a PHY associated with the controller in-
                stance. If this parameter is activated at the board level, the de-
                fault values of the associated parameters mdio-phy-address, phy-poll-
                interval, link-speed and advertise-lower-link-speeds should be checked
                and overwritten at the board level if required.



         * - ``mdio-phy-address``
           - ``int``
           - .. code-block:: none

                The address on the MDIO bus of the PHY associated with the controller
                instance. Set the address to 0 for auto-detection (first responding
                PHY will be claimed by the driver, watch out in case of shared MDIO
                use), or to a fixed address between 1 and 32.



             This property is **required**.

         * - ``phy-poll-interval``
           - ``int``
           - .. code-block:: none

                PHY status polling interval in milliseconds for a driver instance
                managing an associated PHY.



             This property is **required**.

         * - ``link-speed``
           - ``int``
           - .. code-block:: none

                Nominal link speed. If no PHY is managed by an instance of this driver,
                the respective controller will be configured to match the link speed
                specified here. If a PHY is managed by the driver, advertisement of
                the link speed specified here will be requested. If the optional pro-
                perty advertise-lower-link-speeds is set, advertisement of the link
                speed specified here plus any valid link speed below this value will
                be requested.



             This property is **required**.

             Legal values: ``1``, ``2``, ``3``

         * - ``advertise-lower-link-speeds``
           - ``boolean``
           - .. code-block:: none

                Indicates to a driver instance which manages an associated PHY on
                the MDIO bus to include link speeds lower than the nominal value
                set in the link-speed property in the advertisement when requesting
                link speed auto-negotiation with a peer system.



         * - ``handle-rx-in-isr``
           - ``boolean``
           - .. code-block:: none

                Moves the handling of the frame received interrupt including the
                transfer of packet data from the DMA to network packet buffers and
                the subsequent propagation of the received packets to the network
                stack into the context of the ISR. Due to the unpredictability of
                the runtime of the ISR whenever large amounts of data are received,
                handling of the RX interrupt is normally deferred to the context
                of the system work queue.



         * - ``handle-tx-in-workq``
           - ``boolean``
           - .. code-block:: none

                Moves the handling of the frame transmission done interrupt into the
                context of the system work queue. By default, TX done handling is per-
                formed in the context of the ISR, as it only involves a limited number
                of memory accesses. This option CAN NOT be used if any component ex-
                ists within the current system setup that triggers the transmission
                of packets from within the context of the system work queue!



         * - ``amba-ahb-dbus-width``
           - ``int``
           - .. code-block:: none

                AMBA AHB data bus width.


             This property is **required**.

             Legal values: ``0``, ``1``, ``2``

         * - ``amba-ahb-burst-length``
           - ``int``
           - .. code-block:: none

                AMBA AHB burst length for DMA operations.


             This property is **required**.

             Legal values: ``1``, ``4``, ``8``, ``16``

         * - ``hw-rx-buffer-size``
           - ``int``
           - .. code-block:: none

                Hardware RX buffer size, scalable between 1 kB and 8 kB, where the full
                8 kB should be the default.



             This property is **required**.

             Legal values: ``0``, ``1``, ``2``, ``3``

         * - ``hw-rx-buffer-offset``
           - ``int``
           - .. code-block:: none

                Data offset in the hardware RX packet buffer (in bytes). Valid range is
                0-3 bytes.



             This property is **required**.

         * - ``hw-tx-buffer-size-full``
           - ``boolean``
           - .. code-block:: none

                When set, the hardware TX data buffer will make use of the full 4 kB
                that are available. If unset, the hardware TX data buffer will be
                limited to 2 kB.



         * - ``rx-buffer-descriptors``
           - ``int``
           - .. code-block:: none

                The number of descriptors to be allocated in the RX buffer descriptor
                ring. Must be <= 255.



             This property is **required**.

         * - ``rx-buffer-size``
           - ``int``
           - .. code-block:: none

                The size of each receive data buffer, must be a multiple of 8, highest
                valid value is 16320, values less than 64 are not really useful.



             This property is **required**.

         * - ``tx-buffer-descriptors``
           - ``int``
           - .. code-block:: none

                The number of descriptors to be allocated in the TX buffer descriptor
                ring. Must be <= 255.



             This property is **required**.

         * - ``tx-buffer-size``
           - ``int``
           - .. code-block:: none

                The size of each transmit data buffer, highest valid value is 16380,
                values less than 64 are not really useful.



             This property is **required**.

         * - ``ignore-ipg-rxer``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Ignore IPG rx_er. When set, rx_er has no
                effect on the GEM's operation when rx_dv is low. Set this when using
                the RGMII wrapper in half-duplex mode.



         * - ``disable-reject-nsp``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Receive bad preamble. When set, frames with
                non-standard preamble will not be rejected.



         * - ``ipg-stretch``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable IPG stretch. When set, the transmit
                IPG can be increased above 96 bit times depending on the previous
                frame length using the IPG stretch register.



         * - ``sgmii-mode``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable SGMII mode. Changes the behaviour of
                the auto-negotiation advertisement and link partner ability registers
                to meet the requirements of SGMII and reduces the duration of the link
                timer from 10 ms to 1.6 ms.



         * - ``disable-reject-fcs-crc-errors``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Disable rejection of FCS/CRC errors.
                When set, frames with FCS/CRC errors will not be rejected. FCS error
                statistics will still be collected for frames with bad FCS and FCS
                status will be recorded in the frame's DMA descriptor. This option
                should not be activated for normal operation.



         * - ``rx-halfdup-while-tx``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable frames to be received in half-duplex
                mode while transmitting.



         * - ``rx-checksum-offload``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable RX IP/TCP/UDP checksum offload to
                hardware. Frames with bad IP, TCP or UDP checksums will be discarded.
                This option is NOT supported by the QEMU implementation of the GEM!



         * - ``tx-checksum-offload``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable TX IP/TCP/UDP checksum offload to
                hardware. This option is NOT supported by the QEMU implementation
                of the GEM!



         * - ``disable-pause-copy``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Do not copy received pause frames to memory.
                Set this option in order to prevent valid pause frames from being
                copied to memory. When set, pause frames are not copied to memory
                regardless of the state of the copy all frames bit, whether a hash
                match is found or whether a type ID match is identified. If a desti-
                nation address match is found the pause frame will be copied to
                memory. Note that valid pause frames received will still increment
                pause statistics and pause the transmission of frames as required.



         * - ``discard-rx-fcs``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Remove FCS of received frames.
                When set, received frames will be written to memory without their
                frame check sequence (last 4 bytes). The frame length indicated will
                be reduced by four bytes in this mode.



         * - ``discard-rx-length-errors``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Discard frames with length field errors.
                When set, frames with a measured length shorter than the extracted
                length field (as indicated by bytes 13 and 14 in a non-VLAN tagged
                frame) will be discarded. This only applies to frames with a length
                field less than 0x0600.



         * - ``pause-frame``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable pause. When set, transmission will
                pause if a non zero 802.3 classic pause frame is received and PFC
                has not been negotiated.



         * - ``tbi``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable TBI. When set, the TBI interface is en-
                bled instead of the GMII/MII interface.



         * - ``ext-address-match``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable external address match. When set, the
                external address match interface can be used to copy frames to memory.



         * - ``long-frame-rx-support``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable reception of 1536 byte frames.
                Normally, the GEM rejects any frame above 1518 bytes.



         * - ``unicast-hash``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable unicast hash. When set, unicast frames
                will be accepted when the 6 bit hash function of the destination
                address points to a bit that is set in the hash register.



         * - ``multicast-hash``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable multicast hash. When set, multicast
                frames will be accepted when the 6 bit hash function of the desti-
                nation address points to a bit that is set in the hash register.



         * - ``reject-broadcast``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Reject broadcast frames. When set, frames
                addressed to the all-ones broadcast address will be rejected.



         * - ``promiscuous-mode``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable promiscuous mode. When set, all valid
                frames will be accepted.



         * - ``discard-non-vlan``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Discard non-VLAN frames. When set, only VLAN tagged frames will be passed to the address matching logic.


         * - ``full-duplex``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enables full duplex reception and transmission.



         * - ``discard-rx-frame-ahb-unavail``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Discard received packets when no AHB resource
                is available.



         * - ``ahb-packet-endian-swap``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable AHB packet data endianness swap to big
                endian. If this flag is not set, data will be little endian.



         * - ``ahb-md-endian-swap``
           - ``boolean``
           - .. code-block:: none

                Optional feature flag - Enable AHB management descriptor data endian-
                ness swap to big endian. If this flag is not set, data will be little
                endian.



         * - ``local-mac-address``
           - ``uint8-array``
           - .. code-block:: none

                Specifies the MAC address that was assigned to the network device


         * - ``zephyr,random-mac-address``
           - ``boolean``
           - .. code-block:: none

                Use a random MAC address generated when the driver is initialized.
                Note that using this choice and rebooting a board may leave stale
                MAC address in peers' ARP caches and lead to issues and delays in
                communication.  (Use "ip neigh flush all" on Linux peers to clear
                ARP cache.)

                It is driver specific how the OUI octets are handled.

                If set we ignore any setting of the local-mac-address property.



         * - ``phy-handle``
           - ``phandle``
           - .. code-block:: none

                Specifies a reference to a node representing a PHY device.



         * - ``phy-connection-type``
           - ``string``
           - .. code-block:: none

                Specifies the interface connection type between ethernet MAC and PHY.



             Legal values: ``'mii'``, ``'rmii'``, ``'gmii'``



   .. group-tab:: Deprecated node specific properties

      Deprecated properties not inherited from the base binding file.

      (None)

   .. group-tab:: Base properties

      Properties inherited from the base binding file, which defines
      common properties that may be set on many nodes. Not all of these
      may apply to the "xlnx,gem" compatible.

      .. list-table::
         :widths: 1 1 4
         :header-rows: 1

         * - Name
           - Type
           - Details

         * - ``reg``
           - ``array``
           - .. code-block:: none

                register space


             This property is **required**.

             See :ref:`dt-important-props` for more information.

         * - ``interrupts``
           - ``array``
           - .. code-block:: none

                interrupts for device


             This property is **required**.

             See :ref:`dt-important-props` for more information.

         * - ``status``
           - ``string``
           - .. code-block:: none

                indicates the operational status of a device


             Legal values: ``'ok'``, ``'okay'``, ``'disabled'``, ``'reserved'``, ``'fail'``, ``'fail-sss'``

             See :ref:`dt-important-props` for more information.

         * - ``compatible``
           - ``string-array``
           - .. code-block:: none

                compatible strings


             This property is **required**.

             See :ref:`dt-important-props` for more information.

         * - ``reg-names``
           - ``string-array``
           - .. code-block:: none

                name of each register space


         * - ``interrupts-extended``
           - ``compound``
           - .. code-block:: none

                extended interrupt specifier for device


         * - ``interrupt-names``
           - ``string-array``
           - .. code-block:: none

                name of each interrupt


         * - ``interrupt-parent``
           - ``phandle``
           - .. code-block:: none

                phandle to interrupt controller node


         * - ``label``
           - ``string``
           - .. code-block:: none

                Human readable string describing the device (used as device_get_binding() argument)



             See :ref:`dt-important-props` for more information.

             This property is **deprecated**.

         * - ``clocks``
           - ``phandle-array``
           - .. code-block:: none

                Clock gate information


         * - ``clock-names``
           - ``string-array``
           - .. code-block:: none

                name of each clock


         * - ``#address-cells``
           - ``int``
           - .. code-block:: none

                number of address cells in reg property


         * - ``#size-cells``
           - ``int``
           - .. code-block:: none

                number of size cells in reg property


         * - ``dmas``
           - ``phandle-array``
           - .. code-block:: none

                DMA channels specifiers


         * - ``dma-names``
           - ``string-array``
           - .. code-block:: none

                Provided names of DMA channel specifiers


         * - ``io-channels``
           - ``phandle-array``
           - .. code-block:: none

                IO channels specifiers


         * - ``io-channel-names``
           - ``string-array``
           - .. code-block:: none

                Provided names of IO channel specifiers


         * - ``mboxes``
           - ``phandle-array``
           - .. code-block:: none

                mailbox / IPM channels specifiers


         * - ``mbox-names``
           - ``string-array``
           - .. code-block:: none

                Provided names of mailbox / IPM channel specifiers


         * - ``wakeup-source``
           - ``boolean``
           - .. code-block:: none

                Property to identify that a device can be used as wake up source.

                When this property is provided a specific flag is set into the
                device that tells the system that the device is capable of
                wake up the system.

                Wake up capable devices are disabled (interruptions will not wake up
                the system) by default but they can be enabled at runtime if necessary.



         * - ``power-domain``
           - ``phandle``
           - .. code-block:: none


                Power domain the device belongs to.

                The device will be notified when the power domain it belongs to is either
                suspended or resumed.



         * - ``zephyr,pm-device-runtime-auto``
           - ``boolean``
           - .. code-block:: none

                Automatically configure the device for runtime power management after the
                init function runs.