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xlnx,gem

Vendor: Xilinx

Description

Xilinx GEM Ethernet controller

Properties

Node specific propertiesDeprecated node specific propertiesBase properties

Properties not inherited from the base binding file.

Name	Type	Details
clock-frequency	int	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	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	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	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	PHY status polling interval in milliseconds for a driver instance managing an associated PHY. This property is required.
link-speed	int	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	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	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	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	AMBA AHB data bus width. This property is required. Legal values: 0, 1, 2
amba-ahb-burst-length	int	AMBA AHB burst length for DMA operations. This property is required. Legal values: 1, 4, 8, 16
hw-rx-buffer-size	int	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	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	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	The number of descriptors to be allocated in the RX buffer descriptor ring. Must be <= 255. This property is required.
rx-buffer-size	int	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	The number of descriptors to be allocated in the TX buffer descriptor ring. Must be <= 255. This property is required.
tx-buffer-size	int	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	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	Optional feature flag - Receive bad preamble. When set, frames with non-standard preamble will not be rejected.
ipg-stretch	boolean	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	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	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	Optional feature flag - Enable frames to be received in half-duplex mode while transmitting.
rx-checksum-offload	boolean	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	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	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	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	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	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	Optional feature flag - Enable TBI. When set, the TBI interface is en- bled instead of the GMII/MII interface.
ext-address-match	boolean	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	Optional feature flag - Enable reception of 1536 byte frames. Normally, the GEM rejects any frame above 1518 bytes.
unicast-hash	boolean	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	Optional feature flag - Enable multicast hash. When set, mutlicast 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	Optional feature flag - Reject broadcast frames. When set, frames addressed to the all-ones broadcast address will be rejected.
promiscuous-mode	boolean	Optional feature flag - Enable promiscuous mode. When set, all valid frames will be accepted.
discard-non-vlan	boolean	Optional feature flag - Discard non-VLAN frames. When set, only VLAN tagged frames will be passed to the address matching logic.
full-duplex	boolean	Optional feature flag - Enables full duplex reception and transmission.
discard-rx-frame-ahb-unavail	boolean	Optional feature flag - Discard received packets when no AHB resource is available.
ahb-packet-endian-swap	boolean	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	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	Specifies the MAC address that was assigned to the network device
zephyr,random-mac-address	boolean	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.