diff options
| author |   Ovidiu Panait <ovidiu.panait.rb@renesas.com> | 2026-07-22 08:53:51 +0000 |
|---|---|---|
| committer |   Geert Uytterhoeven <geert+renesas@glider.be> | 2026-09-02 14:32:37 +0200 |
| commit | 63016c3a91f2c458ca75869c8c782e899591f22d (patch) | |
| tree | 2ce5c4709c0effdd7fc0d8f3f093aa5963f8c793 | |
| parent | arm64: dts: renesas: r9a09g056: Switch GBETH TX queue scheduling to WRR (diff) | |
arm64: dts: renesas: r9a09g047: Switch GBETH TX queue scheduling to WRR
The GBETH ethernet nodes don't specify a TX scheduling policy, so stmmac
falls back to Strict Priority. In this configuration the queue with the
highest priority gets all the traffic, starving the others under load.
Under sustained UDP TX load with multiple data streams, this starvation
triggers spurious adapter resets due to TX queue timeouts:
iperf3 -c <ip> -i0 -t60 --bind-dev end0 -u -b0 -P4
end0: NETDEV WATCHDOG: CPU: 1: transmit queue 1 timed out 5228 ms
end0: Reset adapter.
Investigation shows that only the highest priority queue is advancing
while the others stall for more than 5 seconds, causing a netdev watchdog
reset.
Switch the TX scheduling policy to Weighted-Round-Robin (WRR) so that
traffic is processed across all queues, eliminating the stalls.
Fixes: 41ffbb1c42d3 ("arm64: dts: renesas: r9a09g047: Add GBETH nodes")
Signed-off-by: Ovidiu Panait <ovidiu.panait.rb@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
Link: https://patch.msgid.link/20260722085353.136986-4-ovidiu.panait.rb@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
| -rw-r--r-- | arch/arm64/boot/dts/renesas/r9a09g047.dtsi | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/arm64/boot/dts/renesas/r9a09g047.dtsi b/arch/arm64/boot/dts/renesas/r9a09g047.dtsi index 73757e8e2197..060405d4a2dd 100644 --- a/arch/arm64/boot/dts/renesas/r9a09g047.dtsi +++ b/arch/arm64/boot/dts/renesas/r9a09g047.dtsi @@ -1913,23 +1913,28 @@ mtl_tx_setup0: tx-queues-config { snps,tx-queues-to-use = <4>; + snps,tx-sched-wrr; queue0 { + snps,weight = <0x10>; snps,dcb-algorithm; snps,priority = <0x1>; }; queue1 { + snps,weight = <0x12>; snps,dcb-algorithm; snps,priority = <0x2>; }; queue2 { + snps,weight = <0x14>; snps,dcb-algorithm; snps,priority = <0x4>; }; queue3 { + snps,weight = <0x18>; snps,dcb-algorithm; snps,priority = <0x8>; }; @@ -2013,23 +2018,28 @@ mtl_tx_setup1: tx-queues-config { snps,tx-queues-to-use = <4>; + snps,tx-sched-wrr; queue0 { + snps,weight = <0x10>; snps,dcb-algorithm; snps,priority = <0x1>; }; queue1 { + snps,weight = <0x12>; snps,dcb-algorithm; snps,priority = <0x2>; }; queue2 { + snps,weight = <0x14>; snps,dcb-algorithm; snps,priority = <0x4>; }; queue3 { + snps,weight = <0x18>; snps,dcb-algorithm; snps,priority = <0x8>; }; |