From 5fd82200d870a5dd3e509c98ef2041f580b2c0e1 Mon Sep 17 00:00:00 2001 From: laurent brando Date: Mon, 27 Jul 2020 18:26:14 +0800 Subject: [PATCH] net: mscc: ocelot: fix hardware timestamp dequeue logic The next hw timestamp should be snapshoot to the read registers only once the current timestamp has been read. If none of the pending skbs matches the current HW timestamp just gracefully flush the available timestamp by reading it. Signed-off-by: laurent brando Signed-off-by: Vladimir Oltean Signed-off-by: Yangbo Lu Signed-off-by: David S. Miller --- drivers/net/ethernet/mscc/ocelot.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c index 9cfe1fd..f17da67 100644 --- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -748,21 +748,21 @@ void ocelot_get_txtstamp(struct ocelot *ocelot) spin_unlock_irqrestore(&port->tx_skbs.lock, flags); - /* Next ts */ - ocelot_write(ocelot, SYS_PTP_NXT_PTP_NXT, SYS_PTP_NXT); + /* Get the h/w timestamp */ + ocelot_get_hwtimestamp(ocelot, &ts); if (unlikely(!skb_match)) continue; - /* Get the h/w timestamp */ - ocelot_get_hwtimestamp(ocelot, &ts); - /* Set the timestamp into the skb */ memset(&shhwtstamps, 0, sizeof(shhwtstamps)); shhwtstamps.hwtstamp = ktime_set(ts.tv_sec, ts.tv_nsec); skb_tstamp_tx(skb_match, &shhwtstamps); dev_kfree_skb_any(skb_match); + + /* Next ts */ + ocelot_write(ocelot, SYS_PTP_NXT_PTP_NXT, SYS_PTP_NXT); } } EXPORT_SYMBOL(ocelot_get_txtstamp); -- 2.7.4