Lines Matching +full:tx +full:- +full:device
1 .. SPDX-License-Identifier: GPL-2.0
4 AF_XDP TX Metadata
8 via :doc:`af_xdp`. Refer to :doc:`xdp-rx-metadata` on how to access similar
26 ``xdp_desc->addr`` in the umem frame. Within a frame, the metadata
31 +-----------------+---------+----------------------------+
33 +-----------------+---------+----------------------------+
36 xdp_desc->addr
40 use ``xdp_desc->addr - tx_metadata_len`` to locate
47 - ``XDP_TXMD_FLAGS_TIMESTAMP``: requests the device to put transmission
49 - ``XDP_TXMD_FLAGS_CHECKSUM``: requests the device to calculate L4
52 device should store the computed checksum.
53 - ``XDP_TXMD_FLAGS_LAUNCH_TIME``: requests the device to schedule the
54 packet for transmission at a pre-determined time called launch time. The
60 bit in the ``options`` field. Also note that in a multi-buffer packet
63 Software TX Checksum
68 In this case, when running in ``XDK_COPY`` mode, the TX checksum
75 The value of the requested launch time should be based on the device's PTP
79 the device driver without rearranging their order or holding them prior to
82 packets in the same Tx Queue until it is sent. Therefore, it is recommended
86 In scenarios where the launch time offload feature is disabled, the device
94 -------------
97 each individual Tx Queue. By default, the driver configures Tx Queue 0 to
98 support TSO and the rest of the Tx Queues to support TBS. The launch time
99 hardware offload feature can be enabled or disabled by using the tc-etf
103 Transmit Descriptors is a 32-bit value, where the most significant 8 bits
111 ----------
113 For igc, all four Tx Queues support the launch time feature. The launch
115 tc-etf command to call the driver's ndo_setup_tc() callback. When entering
116 TSN mode, the igc driver will reset the device and create a default Qbv
117 schedule with a 1-second cycle time, with all Tx Queues open at all times.
129 Querying Device Capabilities
133 Refer to ``xsk-flags`` features bitmask in
136 - ``tx-timestamp``: device supports ``XDP_TXMD_FLAGS_TIMESTAMP``
137 - ``tx-checksum``: device supports ``XDP_TXMD_FLAGS_CHECKSUM``
138 - ``tx-launch-time-fifo``: device supports ``XDP_TXMD_FLAGS_LAUNCH_TIME``
146 program that handles TX metadata. Also see https://github.com/fomichev/xskgen
147 for a more bare-bones example.