diff options
Diffstat (limited to 'Documentation/networking/dpaa.txt')
| -rw-r--r-- | Documentation/networking/dpaa.txt | 194 |
1 files changed, 0 insertions, 194 deletions
diff --git a/Documentation/networking/dpaa.txt b/Documentation/networking/dpaa.txt deleted file mode 100644 index 76e016d4d344..000000000000 --- a/Documentation/networking/dpaa.txt +++ /dev/null @@ -1,194 +0,0 @@ -The QorIQ DPAA Ethernet Driver -============================== - -Authors: -Madalin Bucur <madalin.bucur@nxp.com> -Camelia Groza <camelia.groza@nxp.com> - -Contents -======== - - - DPAA Ethernet Overview - - DPAA Ethernet Supported SoCs - - Configuring DPAA Ethernet in your kernel - - DPAA Ethernet Frame Processing - - DPAA Ethernet Features - - Debugging - -DPAA Ethernet Overview -====================== - -DPAA stands for Data Path Acceleration Architecture and it is a -set of networking acceleration IPs that are available on several -generations of SoCs, both on PowerPC and ARM64. - -The Freescale DPAA architecture consists of a series of hardware blocks -that support Ethernet connectivity. The Ethernet driver depends upon the -following drivers in the Linux kernel: - - - Peripheral Access Memory Unit (PAMU) (* needed only for PPC platforms) - drivers/iommu/fsl_* - - Frame Manager (FMan) - drivers/net/ethernet/freescale/fman - - Queue Manager (QMan), Buffer Manager (BMan) - drivers/soc/fsl/qbman - -A simplified view of the dpaa_eth interfaces mapped to FMan MACs: - - dpaa_eth /eth0\ ... /ethN\ - driver | | | | - ------------- ---- ----------- ---- ------------- - -Ports / Tx Rx \ ... / Tx Rx \ - FMan | | | | - -MACs | MAC0 | | MACN | - / dtsec0 \ ... / dtsecN \ (or tgec) - / \ / \(or memac) - --------- -------------- --- -------------- --------- - FMan, FMan Port, FMan SP, FMan MURAM drivers - --------------------------------------------------------- - FMan HW blocks: MURAM, MACs, Ports, SP - --------------------------------------------------------- - -The dpaa_eth relation to the QMan, BMan and FMan: - ________________________________ - dpaa_eth / eth0 \ - driver / \ - --------- -^- -^- -^- --- --------- - QMan driver / \ / \ / \ \ / | BMan | - |Rx | |Rx | |Tx | |Tx | | driver | - --------- |Dfl| |Err| |Cnf| |FQs| | | - QMan HW |FQ | |FQ | |FQs| | | | | - / \ / \ / \ \ / | | - --------- --- --- --- -v- --------- - | FMan QMI | | - | FMan HW FMan BMI | BMan HW | - ----------------------- -------- - -where the acronyms used above (and in the code) are: -DPAA = Data Path Acceleration Architecture -FMan = DPAA Frame Manager -QMan = DPAA Queue Manager -BMan = DPAA Buffers Manager -QMI = QMan interface in FMan -BMI = BMan interface in FMan -FMan SP = FMan Storage Profiles -MURAM = Multi-user RAM in FMan -FQ = QMan Frame Queue -Rx Dfl FQ = default reception FQ -Rx Err FQ = Rx error frames FQ -Tx Cnf FQ = Tx confirmation FQs -Tx FQs = transmission frame queues -dtsec = datapath three speed Ethernet controller (10/100/1000 Mbps) -tgec = ten gigabit Ethernet controller (10 Gbps) -memac = multirate Ethernet MAC (10/100/1000/10000) - -DPAA Ethernet Supported SoCs -============================ - -The DPAA drivers enable the Ethernet controllers present on the following SoCs: - -# PPC -P1023 -P2041 -P3041 -P4080 -P5020 -P5040 -T1023 -T1024 -T1040 -T1042 -T2080 -T4240 -B4860 - -# ARM -LS1043A -LS1046A - -Configuring DPAA Ethernet in your kernel -======================================== - -To enable the DPAA Ethernet driver, the following Kconfig options are required: - -# common for arch/arm64 and arch/powerpc platforms -CONFIG_FSL_DPAA=y -CONFIG_FSL_FMAN=y -CONFIG_FSL_DPAA_ETH=y -CONFIG_FSL_XGMAC_MDIO=y - -# for arch/powerpc only -CONFIG_FSL_PAMU=y - -# common options needed for the PHYs used on the RDBs -CONFIG_VITESSE_PHY=y -CONFIG_REALTEK_PHY=y -CONFIG_AQUANTIA_PHY=y - -DPAA Ethernet Frame Processing -============================== - -On Rx, buffers for the incoming frames are retrieved from one of the three -existing buffers pools. The driver initializes and seeds these, each with -buffers of different sizes: 1KB, 2KB and 4KB. - -On Tx, all transmitted frames are returned to the driver through Tx -confirmation frame queues. The driver is then responsible for freeing the -buffers. In order to do this properly, a backpointer is added to the buffer -before transmission that points to the skb. When the buffer returns to the -driver on a confirmation FQ, the skb can be correctly consumed. - -DPAA Ethernet Features -====================== - -Currently the DPAA Ethernet driver enables the basic features required for -a Linux Ethernet driver. The support for advanced features will be added -gradually. - -The driver has Rx and Tx checksum offloading for UDP and TCP. Currently the Rx -checksum offload feature is enabled by default and cannot be controlled through -ethtool. - -The driver has support for multiple prioritized Tx traffic classes. Priorities -range from 0 (lowest) to 3 (highest). These are mapped to HW workqueues with -strict priority levels. Each traffic class contains NR_CPU TX queues. By -default, only one traffic class is enabled and the lowest priority Tx queues -are used. Higher priority traffic classes can be enabled with the mqprio -qdisc. For example, all four traffic classes are enabled on an interface with -the following command. Furthermore, skb priority levels are mapped to traffic -classes as follows: - - * priorities 0 to 3 - traffic class 0 (low priority) - * priorities 4 to 7 - traffic class 1 (medium-low priority) - * priorities 8 to 11 - traffic class 2 (medium-high priority) - * priorities 12 to 15 - traffic class 3 (high priority) - -tc qdisc add dev <int> root handle 1: \ - mqprio num_tc 4 map 0 0 0 0 1 1 1 1 2 2 2 2 3 3 3 3 hw 1 - -Debugging -========= - -The following statistics are exported for each interface through ethtool: - - - interrupt count per CPU - - Rx packets count per CPU - - Tx packets count per CPU - - Tx confirmed packets count per CPU - - Tx S/G frames count per CPU - - Tx error count per CPU - - Rx error count per CPU - - Rx error count per type - - congestion related statistics: - - congestion status - - time spent in congestion - - number of time the device entered congestion - - dropped packets count per cause - -The driver also exports the following information in sysfs: - - - the FQ IDs for each FQ type - /sys/devices/platform/dpaa-ethernet.0/net/<int>/fqids - - - the IDs of the buffer pools in use - /sys/devices/platform/dpaa-ethernet.0/net/<int>/bpids |