From: laurent brando <laurent.brando@nxp.com>
Date: Mon, 27 Jul 2020 18:26:14 +0800
Subject: net: mscc: ocelot: fix hardware timestamp dequeue logic
Git-commit: 5fd82200d870a5dd3e509c98ef2041f580b2c0e1
Patch-mainline: v5.8
References: git-fixes
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 <laurent.brando@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
---
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 9cfe1fd98c30..f17da67a4622 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);
--
2.31.1