All the Industrial Development Kit (IDK) boards can support 2 Ethernet ports per PRUSS (Programmable Real-time Unit Subsystem). Although it is meant to support real-time Industrial Ethernet protocols this wiki page will only describe how to get standard Ethernet working using the Kernel’s PRU Ethernet driver.
Acronyms & definitions
|IDK||Industrial Development Kit|
|PRU||Programmable Real-time Unit|
Table: PRU Ethernet Driver: Acronyms
PRU Ethernet Driver Architecture
Below figure shows the PRU Ethernet Driver architecture.
Each PRUSS instance contains 2 PRU cores and 2 Ethernet PHY interfaces. This means that each PRU core can fully own one Ethernet port allowing us to create a dual Ethernet solution. The firmware running on each PRU implements the Ethernet MAC application. It uses the System OCMC RAM to exchange network packets between firmware and PRU Ethernet kernel driver.
Before the PRU Ethernet kernel driver can start transferring packets, the following things have to be done:
- Initialize the PRU cores and load the correct formware. This is taken care by the Remoteproc core via the PRU Remoteproc driver (pru_rproc.c).
- Initialize the PRUSS Interrupt Controller (INTC) and configure the interrupt mapping as per firmware requirement. This is done by the PRUSS INTC driver (pruss_intc.c).
- Initialize the Ethernet PHYs over the MDIO interface. This is done by the PHY MDIO driver (davinci_mdio.c).
Once all initialization is done the PRU Ethernet driver (prueth.c) takes over and interfaces with the firmware using PRUSS internal RAM (DRAM & SRAM) and the System OCMC RAM. It also interfaces to the Linux Networking stack to provide the standard networking interface to user space.
|1||drivers/net/ethernet/ti/prueth.c||PRU Ethernet driver|
|2||drivers/remoteproc/pruss.c||PRUSS core driver|
|3||drivers/remoteproc/pruss_intc.c||PRUSS INTC driver|
|4||drivers/remoteproc/pru_rproc.c||PRU Remoteproc driver|
|5||drivers/net/ethernet/ti/davinci_mdio.c||PHY MDIO driver|
Board specific Setup Details
This board has only 2 Ethernet ports that can be used either as CPSW Ethernet or PRUSS Ethernet. For PRUSS Ethernet configration place jumpers J18 and J19 at MII position before powering up the board.
This board as one Gigabit (CPSW) Ethernert port and 2 PRUSS Ethernet ports. No special board configuration is needed to use all ports.
This board has one Gigabit (netCP) Ethernet port and 4 PRUSS Ethernet ports. No special board configuration is needed to use all ports.
This board has 2 Gigabit (CPSW) Ethernet ports and 4 PRUSS Ethernet ports. Due to pinmux limitations it can support either of the following configurations
- Jumper J51 placed. LCD + 2 Gigabit (CPSW) + 2 PRUSS Ethernet ports (PRU2_ETH0 and PRU2_ETH1)
- Jumper J51 removed. No LCD, 2 Gigabit (CPSW) + 4 PRUSS Ethernet ports.
NOTE: Jumper must be configured before powering up the board.
This board has 2 Gigabit (CPSW) Ethernet ports and 4 PRUSS Ethernet ports. However, only 2 Gigabit + 2 PRUSS Ethernet ports (PRU2_ETH0 and PRU2_ETH1) are supported due to pinmux limitations.
NOTE: Only ES2.0 silicon (Board Rev1.3 or later) is supported as older Silicon uses a older version of PRUSS core that is not compatible with the supplied firmware.
To enable/disable PRU Ethernet driver support, start the Linux Kernel Configuration tool:
$ make menuconfig ARCH=arm
Make sure Remoteproc and PRUSS core driver is enabled.
Select Device drivers from the main menu.
... [*] Networking support ---> Device Drivers --> File systems ---> ...
Select Remoteproc drivers.
... [*] IOMMU Hardware Support ---> Remoteproc drivers ---> Rpmsg drivers ---> ...
Enable the below drivers.
... <M> Support for Remote Processor subsystem <M> TI PRUSS remoteproc support <M> Keystone Remoteproc support ...
Go back to the Device drivers menu Network device support.
... IEEE 1394 (FireWire) support ---> [*] Network device support ---> [ ] Open-Channel SSD target support ---- ...
Select Ethernet driver support.
... Distributed Switch Architecture drivers ---- [*] Ethernet driver support ---> < > FDDI driver support ...
Select TI PRU Ethernet driver.
... < > TI ThunderLAN support <M> TI PRU Ethernet EMAC/Switch driver [ ] VIA devices ...
Driver Usage & Testing
You can use standard Linux networking tools to test the networking interface (e.g. ifconfig, ping, iperf, scp, ethtool, etc)