From: Grzegorz Nitka Date: Thu, 27 Nov 2025 09:25:58 +0000 (+0100) Subject: ice: fix missing TX timestamps interrupts on E825 devices X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=99854c167cfc113ad863832b1601c4ca1a639cfe;p=thirdparty%2Fkernel%2Flinux.git ice: fix missing TX timestamps interrupts on E825 devices Modify PTP (Precision Time Protocol) configuration on link down flow. Previously, PHY_REG_TX_OFFSET_READY register was cleared in such case. This register is used to determine if the timestamp is valid or not on the hardware side. However, there is a possibility that there is still the packet in the HW queue which originally was supposed to be timestamped but the link is already down and given register is cleared. This potentially might lead to the situation in which that 'delayed' packet's timestamp is treated as invalid one when the link is up again. This in turn leads to the situation in which the driver is not able to effectively clean timestamp memory and interrupt configuration. From the hardware perspective, that 'old' interrupt was not handled properly and even if new timestamp packets are processed, no new interrupts is generated. As a result, providing timestamps to the user applications (like ptp4l) is not possible. The solution for this problem is implemented at the driver level rather than the firmware, and maintains the tx_ready bit high, even during link down events. This avoids entering a potential inconsistent state between the driver and the timestamp hardware. Testing hints: - run PTP traffic at higher rate (like 16 PTP messages per second) - observe ptp4l behaviour at the client side in the following conditions: a) trigger link toggle events. It needs to be physiscal link down/up events b) link speed change In all above cases, PTP processing at ptp4l application should resume always. In failure case, the following permanent error message in ptp4l log was observed: controller-0 ptp4l: err [6175.116] ptp4l-legacy timed out while polling for tx timestamp Fixes: 7cab44f1c35f ("ice: Introduce ETH56G PHY model for E825C products") Reviewed-by: Aleksandr Loktionov Signed-off-by: Grzegorz Nitka Tested-by: Sunitha Mekala (A Contingent worker at Intel) Signed-off-by: Tony Nguyen --- diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c index 4c8d20f2d2c0..0b7c2a13ab04 100644 --- a/drivers/net/ethernet/intel/ice/ice_ptp.c +++ b/drivers/net/ethernet/intel/ice/ice_ptp.c @@ -1347,9 +1347,12 @@ void ice_ptp_link_change(struct ice_pf *pf, bool linkup) /* Do not reconfigure E810 or E830 PHY */ return; case ICE_MAC_GENERIC: - case ICE_MAC_GENERIC_3K_E825: ice_ptp_port_phy_restart(ptp_port); return; + case ICE_MAC_GENERIC_3K_E825: + if (linkup) + ice_ptp_port_phy_restart(ptp_port); + return; default: dev_warn(ice_pf_to_dev(pf), "%s: Unknown PHY type\n", __func__); }