AM6442: Linux HSR, PRP & PTP support on PRU-ICSSG CPSW & CPSW3G

Chris

Part Number: AM6442

Dear TI Team,

In our application, we require support for HSR (High-availability Seamless Redundancy), PRP (Parallel Redundancy Protocol), STP (Spanning Tree Protocol), and PTP (Precision Time Protocol). After reviewing the processor SDK documentation, I noticed that the Linux kernel driver provides support for HSR, PRP, STP, and PTP. Now, I am curious to know whether this same driver can be used for both the PRU-ICSSG CPSW (non-offload HSR/PRP) and CPSW3G. We need to reach a conclusion on whether to use CPSW or CPSW3G for our application.

Thank you

Chris

over 2 years ago

+1 Nick Saulnier over 2 years ago

TI__Guru** 100970 points

Hello Chris,

Another teammate will comment in a bit on the plans for PRU Ethernet & HSR/PRP. I know there is some new software that is in development, but I do not know the details of the timeframe that it will be available.

A quick note on naming:
CPSW and CPSW3G refers to the same piece of hardware (a group of dedicated circuits within the processor that do Ethernet). "CPSW" is the generic name for that group of circuits, while CPSW3G gives specific details about how many gigabit ports are on that CPSW (1 internal gigabit port going towards whichever processor is controlling the CPSW, and 2 external facing gigabit ports that can be connected to PHYs). For more information, see https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1198772/am6412-am6412-3-port-switch-and-pru

That is distinct from the CPSW2G on AM65x (only 1 external facing gigabit port), and other CPSW variations you may find on larger Jacinto family devices with many additional ports.

PRU_ICSSG refers to a group of programmable cores and their associated peripherals (instead of dedicated circuits). The PRU cores can be programmed to implement some kind of Ethernet or networking protocol, in addition to many other things like motor control, sensor monitoring & control, etc.

Regards,

Nick

+1 Pekka Varis over 2 years ago in reply to Nick Saulnier

TI__Mastermind 27050 points

Yes the interface is the same based on https://docs.kernel.org/networking/netdev-features.html . The ICSSG based implementation will include HSR packet forwarding (cut-through) using hsr-fwd-offload .

See https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1240831/am6421-hsr-high-availability-seamless-redundancy-availability for schedule and details of what is offloaded.

Pekka