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xlnx,gem

Vendor: Xilinx

Description

Xilinx GEM Ethernet controller

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.

phy-handle

phandle

Specifies a reference to a node representing a PHY device.

phy-connection-type

string

Specifies the interface connection type between ethernet MAC and PHY.

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