This is a note to let you know that I've just added the patch titled
igc: Fix missing time sync events
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
igc-fix-missing-time-sync-events.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b83d6b16a250bc1ac60713e386ee7e9e20c74a54
Author: Vinicius Costa Gomes <vinicius.gomes@xxxxxxxxx>
Date: Tue Feb 20 15:57:10 2024 -0800
igc: Fix missing time sync events
[ Upstream commit 244ae992e3e80e5c9c272c77324c831148457f95 ]
Fix "double" clearing of interrupts, which can cause external events
or timestamps to be missed.
The IGC_TSIRC Time Sync Interrupt Cause register can be cleared in two
ways, by either reading it or by writing '1' into the specific cause
bit. This is documented in section 8.16.1.
The following flow was used:
1. read IGC_TSIRC into 'tsicr';
2. handle the interrupts present in 'tsirc' and mark them in 'ack';
3. write 'ack' into IGC_TSICR;
As both (1) and (3) will clear the interrupt cause, if the same
interrupt happens again between (1) and (3) it will be ignored,
causing events to be missed.
Remove the extra clear in (3).
Fixes: 2c344ae24501 ("igc: Add support for TX timestamping")
Reviewed-by: Kurt Kanzenbach <kurt@xxxxxxxxxxxxx>
Tested-by: Kurt Kanzenbach <kurt@xxxxxxxxxxxxx> # Intel i225
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@xxxxxxxxx>
Tested-by: Naama Meir <naamax.meir@xxxxxxxxxxxxxxx>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 81c21a893ede9..e447ba0370568 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -5302,25 +5302,22 @@ igc_features_check(struct sk_buff *skb, struct net_device *dev,
static void igc_tsync_interrupt(struct igc_adapter *adapter)
{
- u32 ack, tsauxc, sec, nsec, tsicr;
struct igc_hw *hw = &adapter->hw;
+ u32 tsauxc, sec, nsec, tsicr;
struct ptp_clock_event event;
struct timespec64 ts;
tsicr = rd32(IGC_TSICR);
- ack = 0;
if (tsicr & IGC_TSICR_SYS_WRAP) {
event.type = PTP_CLOCK_PPS;
if (adapter->ptp_caps.pps)
ptp_clock_event(adapter->ptp_clock, &event);
- ack |= IGC_TSICR_SYS_WRAP;
}
if (tsicr & IGC_TSICR_TXTS) {
/* retrieve hardware timestamp */
igc_ptp_tx_tstamp_event(adapter);
- ack |= IGC_TSICR_TXTS;
}
if (tsicr & IGC_TSICR_TT0) {
@@ -5334,7 +5331,6 @@ static void igc_tsync_interrupt(struct igc_adapter *adapter)
wr32(IGC_TSAUXC, tsauxc);
adapter->perout[0].start = ts;
spin_unlock(&adapter->tmreg_lock);
- ack |= IGC_TSICR_TT0;
}
if (tsicr & IGC_TSICR_TT1) {
@@ -5348,7 +5344,6 @@ static void igc_tsync_interrupt(struct igc_adapter *adapter)
wr32(IGC_TSAUXC, tsauxc);
adapter->perout[1].start = ts;
spin_unlock(&adapter->tmreg_lock);
- ack |= IGC_TSICR_TT1;
}
if (tsicr & IGC_TSICR_AUTT0) {
@@ -5358,7 +5353,6 @@ static void igc_tsync_interrupt(struct igc_adapter *adapter)
event.index = 0;
event.timestamp = sec * NSEC_PER_SEC + nsec;
ptp_clock_event(adapter->ptp_clock, &event);
- ack |= IGC_TSICR_AUTT0;
}
if (tsicr & IGC_TSICR_AUTT1) {
@@ -5368,11 +5362,7 @@ static void igc_tsync_interrupt(struct igc_adapter *adapter)
event.index = 1;
event.timestamp = sec * NSEC_PER_SEC + nsec;
ptp_clock_event(adapter->ptp_clock, &event);
- ack |= IGC_TSICR_AUTT1;
}
-
- /* acknowledge the interrupts */
- wr32(IGC_TSICR, ack);
}
/**
