On Fri, Jan 30, 2026 at 06:13:42PM +0530, Parvathi Pudi wrote:

Hi,

The DUAL-EMAC patch series for Megabit Industrial Communication Sub-system
(ICSSM), which provides the foundational support for Ethernet functionality
over PRU-ICSS on the TI SOCs (AM335x, AM437x, and AM57x), was merged into
net-next recently [1].

This patch series enhances the PRU-ICSSM Ethernet driver to support bridge
(STP/RSTP) SWITCH mode, which has been implemented using the "switchdev"
framework and interacts with the "mstp daemon" for STP and RSTP management
in userspace.

When the  SWITCH mode is enabled, forwarding of Ethernet packets using
either the traditional store-and-forward mechanism or via cut-through is
offloaded to the two PRU based Ethernet interfaces available within the
ICSSM. The firmware running on the PRU inspects the bridge port states and
performs necessary checks before forwarding a packet. This improves the
overall system performance and significantly reduces the packet forwarding
latency.

Protocol switching from Dual-EMAC to bridge (STP/RSTP) SWITCH mode can be
done as follows.

Assuming eth2 and eth3 are the two physical ports of the ICSS2 instance:

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brctl addbr br0
ip maddr add 01:80:c2:00:00:00 dev br0
ip link set dev br0 address $(cat /sys/class/net/eth2/address)
brctl addif br0 eth2
brctl addif br0 eth3
mstpd
brctl stp br0 on

# STP to RSTP mode

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mstpctl setforcevers br0 rstp
ip link set dev br0 up

To revert back to the default dual EMAC mode, the steps are as follows:

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ip link set dev br0 down
brctl delif br0 eth2
brctl delif br0 eth3
brctl delbr br0

The patches presented in this series have gone through the patch verification
tools and no warnings or errors are reported.

Sample test logs obtained from AM33x, AM43x and AM57x verifying the
functionality on Linux next kernel are available here:

[Interface up Testing](https://gist.github.com/ParvathiPudi/91b05f4e6d69d72f55ddd4e95301ab20)

[Ping Testing](https://gist.github.com/ParvathiPudi/9e7573ea85ef72a3ebcbdb4c902f3b8a)

[Iperf Testing](https://gist.github.com/ParvathiPudi/30abedf115aba19542e0156486766553)

[1] https://lore.kernel.org/all/20250912104741.528721-1-parvathi@couthit.com/ (local)

This is the v13 of the patch series [v1]. This version of the patchset
addresses the comments made on [v12] of the series.

Changes from v12 to v13:

*) Reverted the use of kmalloc_obj() and kzalloc_obj() back to kmalloc() and kzalloc(),
since the corresponding changes are not reflected in the net-next branch.
*) Addressed AI review warnings on patch 3 of the series.
*) Rebased the series on latest net-next.

Thanks,

I notice that this series has been marked as Changes Requested in
Patchwork. But overall it looks good to me.

Feel free to add the following for the series:
Reviewed-by: Simon Horman <horms@kernel.org>