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

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

[Rohan G Thomas via B4 Relay]

From: Rohan G Thomas <rohan.g.thomas@altera.com>

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")
Signed-off-by: Rohan G Thomas <rohan.g.thomas@altera.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 6cacedb2c9b3fefdd4c9ec8ba98d389443d21ebd..2885434cb0bea7166dca2a914a6c07e21c98e5b9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -665,7 +665,8 @@ static int stmmac_hwtstamp_set(struct net_device *dev,
 			config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
 			ptp_v2 = PTP_TCR_TSVER2ENA;
 			snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
-			if (priv->synopsys_id < DWMAC_CORE_4_10)
+			if (priv->synopsys_id < DWMAC_CORE_3_70 &&
+			    priv->plat->core_type != DWMAC_CORE_XGMAC)
 				ts_event_en = PTP_TCR_TSEVNTENA;
 			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
 			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;

---
base-commit: e3daf0e7fe9758613bec324fd606ed9caa187f74
change-id: 20251125-ext-ptp-fix-c7be5ccc9581

Best regards,
-- 
Rohan G Thomas <rohan.g.thomas@altera.com>

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

[Andrew Lunn]

On Tue, Nov 25, 2025 at 10:50:02PM +0800, Rohan G Thomas via B4 Relay wrote:
> From: Rohan G Thomas <rohan.g.thomas@altera.com>
> 
> 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

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

[Russell King (Oracle)]

On Tue, Nov 25, 2025 at 10:50:02PM +0800, Rohan G Thomas via B4 Relay wrote:
> From: Rohan G Thomas <rohan.g.thomas@altera.com>
> 
> 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

bits

> register must be set to 2'b00, and the TSEVNTENA bit must be cleared
> to 0'b0.

Are you sure 3.70 is the appropriate point. According to the 3.74
databook, SNAPTYPSEL changed between 3.5 and 3.6.

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

[G Thomas, Rohan]

Hi Andrew,

On 11/25/2025 9:56 PM, Andrew Lunn wrote:
> On Tue, Nov 25, 2025 at 10:50:02PM +0800, Rohan G Thomas via B4 Relay wrote:
>> From: Rohan G Thomas <rohan.g.thomas@altera.com>
>>
>> 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

Thanks! Sure, I will send the next version to net instead of net-next.

Best Regards,
Rohan

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

[G Thomas, Rohan]

Hi Russell,

Thanks for reviewing the patch.

On 11/26/2025 4:49 AM, Russell King (Oracle) wrote:
> On Tue, Nov 25, 2025 at 10:50:02PM +0800, Rohan G Thomas via B4 Relay wrote:
>> From: Rohan G Thomas <rohan.g.thomas@altera.com>
>>
>> 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
> 
> bits

Sure, will fix this in the next version.

> 
>> register must be set to 2'b00, and the TSEVNTENA bit must be cleared
>> to 0'b0.
> 
> Are you sure 3.70 is the appropriate point. According to the 3.74
> databook, SNAPTYPSEL changed between 3.5 and 3.6.
> 

I’m not entirely sure. As per the dwmac databook notes that SNAPTYPSEL
is not backward compatible with functions described in release 3.50a,
but it’s unclear if this specifically relates to TSEVNTENA. My
understanding is that at least from 3.70a, TSEVNTENA must be cleared to
enable time stamping for all the events.

Best Regards,
Rohan