[PATCH v4] net/ice: fix incorrect reading of PHY timestamp

[Soumyadeep Hore <soumyadeep.hore@intel.com>]

In ICE PMD, previously the ready bitmap checking before reading
PHY timestamp was not present. This caused incorrect Tx
timestamping.

The ready bitmap checking is enabled and PHY timestamp is read once
the ready bitmap gives positive value.

Fixes: 881169950d80 ("net/ice/base: implement initial PTP support for E830")
Cc: stable@dpdk.org

Signed-off-by: Soumyadeep Hore <soumyadeep.hore@intel.com>
---
v4:
- Addressed Bruce comments for do while loop introduction
---
v3:
- Decreased the end time delay from 1 second to 10 microseconds
---
v2:
- Addressed Bruce's comments
---
 drivers/net/ice/ice_ethdev.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ice/ice_ethdev.c b/drivers/net/ice/ice_ethdev.c
index 70298ac330..7e2c6107ff 100644
--- a/drivers/net/ice/ice_ethdev.c
+++ b/drivers/net/ice/ice_ethdev.c
@@ -6597,10 +6597,27 @@ ice_timesync_read_tx_timestamp(struct rte_eth_dev *dev,
 	struct ice_hw *hw = ICE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
 	struct ice_adapter *ad =
 			ICE_DEV_PRIVATE_TO_ADAPTER(dev->data->dev_private);
-	uint64_t ts_ns, tstamp;
+	uint64_t ts_ns, tstamp, tstamp_ready = 0;
+	uint64_t end_time;
 	const uint64_t mask = 0xFFFFFFFF;
 	int ret;
 
+	/* Set the end time with a delay of 10 microseconds */
+	end_time = rte_get_timer_cycles() + (rte_get_timer_hz() / 100000);
+
+	do {
+		ret = ice_get_phy_tx_tstamp_ready(hw, ad->ptp_tx_block, &tstamp_ready);
+		if (ret) {
+			PMD_DRV_LOG(ERR, "Failed to get phy ready for timestamp");
+			return -1;
+		}
+
+		if (rte_get_timer_cycles() > end_time) {
+			PMD_DRV_LOG(ERR, "Timeout to get phy ready for timestamp");
+			return -1;
+		}
+	} while ((tstamp_ready & BIT_ULL(0)) == 0);
+
 	ret = ice_read_phy_tstamp(hw, ad->ptp_tx_block, ad->ptp_tx_index, &tstamp);
 	if (ret || tstamp == 0) {
 		PMD_DRV_LOG(ERR, "Failed to read phy timestamp");
-- 
2.43.0