Re: [PATCH net-next] net: stmmac: Fix E2E delay mechanism

From: Andrew Lunn
Date: Tue Nov 25 2025 - 11:27:32 EST


On Tue, Nov 25, 2025 at 10:50:02PM +0800, Rohan G Thomas via B4 Relay wrote:
> From: Rohan G Thomas <rohan.g.thomas@xxxxxxxxxx>
>
> For E2E delay mechanism, "received DELAY_REQ without timestamp" error
> messages shows up for dwmac v3.70+ and dwxgmac IPs.
>
> This issue affects socfpga platforms, Agilex7 (dwmac 3.70) and
> Agilex5 (dwxgmac). According to the databook, to enable timestamping
> for all events, the SNAPTYPSEL bit in the MAC_Timestamp_Control
> register must be set to 2'b00, and the TSEVNTENA bit must be cleared
> to 0'b0.
>
> Commit 3cb958027cb8 ("net: stmmac: Fix E2E delay mechanism") already
> addresses this problem for all dwmacs above version v4.10. However,
> same holds true for v3.70 and above, as well as for dwxgmac. Updates
> the check accordingly.
>
> Fixes: 14f347334bf2 ("net: stmmac: Correctly take timestamp for PTPv2")
> Fixes: f2fb6b6275eb ("net: stmmac: enable timestamp snapshot for required PTP packets in dwmac v5.10a")
> Fixes: 3cb958027cb8 ("net: stmmac: Fix E2E delay mechanism")

Given the list of Fixes: do you want this back ported to stable? If
so, you should not submit it for net-next.

Andrew