From 4406e977a4a1e997818b6d77c3218ef8d15b2abf Mon Sep 17 00:00:00 2001 From: Vinicius Costa Gomes Date: Tue, 18 Aug 2020 16:40:02 -0700 Subject: [PATCH] igc: Fix not considering the TX delay for timestamps When timestamping a packet there's a delay between the start of the packet and the point where the hardware actually captures the timestamp. This difference needs to be considered if we want accurate timestamps. This was done on the RX side, but not on the TX side. Fixes: 2c344ae24501 ("igc: Add support for TX timestamping") Signed-off-by: Vinicius Costa Gomes Tested-by: Aaron Brown Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/igc/igc_ptp.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c index 36c999250fcc21..6a9b5102aa55e6 100644 --- a/drivers/net/ethernet/intel/igc/igc_ptp.c +++ b/drivers/net/ethernet/intel/igc/igc_ptp.c @@ -364,6 +364,7 @@ static void igc_ptp_tx_hwtstamp(struct igc_adapter *adapter) struct sk_buff *skb = adapter->ptp_tx_skb; struct skb_shared_hwtstamps shhwtstamps; struct igc_hw *hw = &adapter->hw; + int adjust = 0; u64 regval; if (WARN_ON_ONCE(!skb)) @@ -373,6 +374,24 @@ static void igc_ptp_tx_hwtstamp(struct igc_adapter *adapter) regval |= (u64)rd32(IGC_TXSTMPH) << 32; igc_ptp_systim_to_hwtstamp(adapter, &shhwtstamps, regval); + switch (adapter->link_speed) { + case SPEED_10: + adjust = IGC_I225_TX_LATENCY_10; + break; + case SPEED_100: + adjust = IGC_I225_TX_LATENCY_100; + break; + case SPEED_1000: + adjust = IGC_I225_TX_LATENCY_1000; + break; + case SPEED_2500: + adjust = IGC_I225_TX_LATENCY_2500; + break; + } + + shhwtstamps.hwtstamp = + ktime_add_ns(shhwtstamps.hwtstamp, adjust); + /* Clear the lock early before calling skb_tstamp_tx so that * applications are not woken up before the lock bit is clear. We use * a copy of the skb pointer to ensure other threads can't change it