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diff --git a/Documentation/networking/device_drivers/freescale/dpaa2/ethernet-driver.rst b/Documentation/networking/device_drivers/freescale/dpaa2/ethernet-driver.rst deleted file mode 100644 index cb4c9a0c5a17..000000000000 --- a/Documentation/networking/device_drivers/freescale/dpaa2/ethernet-driver.rst +++ /dev/null @@ -1,185 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 -.. include:: <isonum.txt> - -=============================== -DPAA2 Ethernet driver -=============================== - -:Copyright: |copy| 2017-2018 NXP - -This file provides documentation for the Freescale DPAA2 Ethernet driver. - -Supported Platforms -=================== -This driver provides networking support for Freescale DPAA2 SoCs, e.g. -LS2080A, LS2088A, LS1088A. - - -Architecture Overview -===================== -Unlike regular NICs, in the DPAA2 architecture there is no single hardware block -representing network interfaces; instead, several separate hardware resources -concur to provide the networking functionality: - -- network interfaces -- queues, channels -- buffer pools -- MAC/PHY - -All hardware resources are allocated and configured through the Management -Complex (MC) portals. MC abstracts most of these resources as DPAA2 objects -and exposes ABIs through which they can be configured and controlled. A few -hardware resources, like queues, do not have a corresponding MC object and -are treated as internal resources of other objects. - -For a more detailed description of the DPAA2 architecture and its object -abstractions see *Documentation/networking/device_drivers/freescale/dpaa2/overview.rst*. - -Each Linux net device is built on top of a Datapath Network Interface (DPNI) -object and uses Buffer Pools (DPBPs), I/O Portals (DPIOs) and Concentrators -(DPCONs). - -Configuration interface:: - - ----------------------- - | DPAA2 Ethernet Driver | - ----------------------- - . . . - . . . - . . . . . . . . . . . . - . . . - . . . - ---------- ---------- ----------- - | DPBP API | | DPNI API | | DPCON API | - ---------- ---------- ----------- - . . . software - ======= . ========== . ============ . =================== - . . . hardware - ------------------------------------------ - | MC hardware portals | - ------------------------------------------ - . . . - . . . - ------ ------ ------- - | DPBP | | DPNI | | DPCON | - ------ ------ ------- - -The DPNIs are network interfaces without a direct one-on-one mapping to PHYs. -DPBPs represent hardware buffer pools. Packet I/O is performed in the context -of DPCON objects, using DPIO portals for managing and communicating with the -hardware resources. - -Datapath (I/O) interface:: - - ----------------------------------------------- - | DPAA2 Ethernet Driver | - ----------------------------------------------- - | ^ ^ | | - | | | | | - enqueue| dequeue| data | dequeue| seed | - (Tx) | (Rx, TxC)| avail.| request| buffers| - | | notify| | | - | | | | | - V | | V V - ----------------------------------------------- - | DPIO Driver | - ----------------------------------------------- - | | | | | software - | | | | | ================ - | | | | | hardware - ----------------------------------------------- - | I/O hardware portals | - ----------------------------------------------- - | ^ ^ | | - | | | | | - | | | V | - V | ================ V - ---------------------- | ------------- - queues ---------------------- | | Buffer pool | - ---------------------- | ------------- - ======================= - Channel - -Datapath I/O (DPIO) portals provide enqueue and dequeue services, data -availability notifications and buffer pool management. DPIOs are shared between -all DPAA2 objects (and implicitly all DPAA2 kernel drivers) that work with data -frames, but must be affine to the CPUs for the purpose of traffic distribution. - -Frames are transmitted and received through hardware frame queues, which can be -grouped in channels for the purpose of hardware scheduling. The Ethernet driver -enqueues TX frames on egress queues and after transmission is complete a TX -confirmation frame is sent back to the CPU. - -When frames are available on ingress queues, a data availability notification -is sent to the CPU; notifications are raised per channel, so even if multiple -queues in the same channel have available frames, only one notification is sent. -After a channel fires a notification, is must be explicitly rearmed. - -Each network interface can have multiple Rx, Tx and confirmation queues affined -to CPUs, and one channel (DPCON) for each CPU that services at least one queue. -DPCONs are used to distribute ingress traffic to different CPUs via the cores' -affine DPIOs. - -The role of hardware buffer pools is storage of ingress frame data. Each network -interface has a privately owned buffer pool which it seeds with kernel allocated -buffers. - - -DPNIs are decoupled from PHYs; a DPNI can be connected to a PHY through a DPMAC -object or to another DPNI through an internal link, but the connection is -managed by MC and completely transparent to the Ethernet driver. - -:: - - --------- --------- --------- - | eth if1 | | eth if2 | | eth ifn | - --------- --------- --------- - . . . - . . . - . . . - --------------------------- - | DPAA2 Ethernet Driver | - --------------------------- - . . . - . . . - . . . - ------ ------ ------ ------- - | DPNI | | DPNI | | DPNI | | DPMAC |----+ - ------ ------ ------ ------- | - | | | | | - | | | | ----- - =========== ================== | PHY | - ----- - -Creating a Network Interface -============================ -A net device is created for each DPNI object probed on the MC bus. Each DPNI has -a number of properties which determine the network interface configuration -options and associated hardware resources. - -DPNI objects (and the other DPAA2 objects needed for a network interface) can be -added to a container on the MC bus in one of two ways: statically, through a -Datapath Layout Binary file (DPL) that is parsed by MC at boot time; or created -dynamically at runtime, via the DPAA2 objects APIs. - - -Features & Offloads -=================== -Hardware checksum offloading is supported for TCP and UDP over IPv4/6 frames. -The checksum offloads can be independently configured on RX and TX through -ethtool. - -Hardware offload of unicast and multicast MAC filtering is supported on the -ingress path and permanently enabled. - -Scatter-gather frames are supported on both RX and TX paths. On TX, SG support -is configurable via ethtool; on RX it is always enabled. - -The DPAA2 hardware can process jumbo Ethernet frames of up to 10K bytes. - -The Ethernet driver defines a static flow hashing scheme that distributes -traffic based on a 5-tuple key: src IP, dst IP, IP proto, L4 src port, -L4 dst port. No user configuration is supported for now. - -Hardware specific statistics for the network interface as well as some -non-standard driver stats can be consulted through ethtool -S option. |