diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 1103c210b4e3..a25ceecf1ea7 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -730,6 +730,15 @@ static u8 iavf_select_rx_desc_format(const struct iavf_adapter *adapter)
 	if (!IAVF_RXDID_ALLOWED(adapter))
 		return VIRTCHNL_RXDID_1_32B_BASE;
 
+	/* Rx timestamping requires the use of flexible NIC descriptors */
+	if (iavf_ptp_cap_supported(adapter, VIRTCHNL_1588_PTP_CAP_RX_TSTAMP)) {
+		if (rxdids & BIT(VIRTCHNL_RXDID_2_FLEX_SQ_NIC))
+			return VIRTCHNL_RXDID_2_FLEX_SQ_NIC;
+
+		pci_warn(adapter->pdev,
+			 "Unable to negotiate flexible descriptor format\n");
+	}
+
 	/* Warn if the PF does not list support for the default legacy
 	 * descriptor format. This shouldn't happen, as this is the format
 	 * used if VIRTCHNL_VF_OFFLOAD_RX_FLEX_DESC is not supported. It is
diff --git a/drivers/net/ethernet/intel/iavf/iavf_ptp.c b/drivers/net/ethernet/intel/iavf/iavf_ptp.c
index 4246ddfa6f0d..b4d5eda2e84f 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_ptp.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_ptp.c
@@ -394,6 +394,9 @@ void iavf_ptp_release(struct iavf_adapter *adapter)
 	}
 	adapter->aq_required &= ~IAVF_FLAG_AQ_SEND_PTP_CMD;
 	mutex_unlock(&adapter->ptp.aq_cmd_lock);
+
+	adapter->ptp.hwtstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
+	iavf_ptp_disable_rx_tstamp(adapter);
 }
 
 /**
@@ -422,3 +425,61 @@ void iavf_ptp_process_caps(struct iavf_adapter *adapter)
 		iavf_ptp_disable_rx_tstamp(adapter);
 	}
 }
+
+/**
+ * iavf_ptp_extend_32b_timestamp - Convert a 32b nanoseconds timestamp to 64b
+ * nanoseconds
+ * @cached_phc_time: recently cached copy of PHC time
+ * @in_tstamp: Ingress/egress 32b nanoseconds timestamp value
+ *
+ * Hardware captures timestamps which contain only 32 bits of nominal
+ * nanoseconds, as opposed to the 64bit timestamps that the stack expects.
+ *
+ * Extend the 32bit nanosecond timestamp using the following algorithm and
+ * assumptions:
+ *
+ * 1) have a recently cached copy of the PHC time
+ * 2) assume that the in_tstamp was captured 2^31 nanoseconds (~2.1
+ *    seconds) before or after the PHC time was captured.
+ * 3) calculate the delta between the cached time and the timestamp
+ * 4) if the delta is smaller than 2^31 nanoseconds, then the timestamp was
+ *    captured after the PHC time. In this case, the full timestamp is just
+ *    the cached PHC time plus the delta.
+ * 5) otherwise, if the delta is larger than 2^31 nanoseconds, then the
+ *    timestamp was captured *before* the PHC time, i.e. because the PHC
+ *    cache was updated after the timestamp was captured by hardware. In this
+ *    case, the full timestamp is the cached time minus the inverse delta.
+ *
+ * This algorithm works even if the PHC time was updated after a Tx timestamp
+ * was requested, but before the Tx timestamp event was reported from
+ * hardware.
+ *
+ * This calculation primarily relies on keeping the cached PHC time up to
+ * date. If the timestamp was captured more than 2^31 nanoseconds after the
+ * PHC time, it is possible that the lower 32bits of PHC time have
+ * overflowed more than once, and we might generate an incorrect timestamp.
+ *
+ * This is prevented by (a) periodically updating the cached PHC time once
+ * a second, and (b) discarding any Tx timestamp packet if it has waited for
+ * a timestamp for more than one second.
+ *
+ * Return: extended timestamp (to 64b).
+ */
+u64 iavf_ptp_extend_32b_timestamp(u64 cached_phc_time, u32 in_tstamp)
+{
+	u32 low = lower_32_bits(cached_phc_time);
+	u32 delta = in_tstamp - low;
+	u64 ns;
+
+	/* Do not assume that the in_tstamp is always more recent than the
+	 * cached PHC time. If the delta is large, it indicates that the
+	 * in_tstamp was taken in the past, and should be converted
+	 * forward.
+	 */
+	if (delta > S32_MAX)
+		ns = cached_phc_time - (low - in_tstamp);
+	else
+		ns = cached_phc_time + delta;
+
+	return ns;
+}
diff --git a/drivers/net/ethernet/intel/iavf/iavf_ptp.h b/drivers/net/ethernet/intel/iavf/iavf_ptp.h
index 0801e3ff5a59..783b8f287cd9 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_ptp.h
+++ b/drivers/net/ethernet/intel/iavf/iavf_ptp.h
@@ -6,6 +6,9 @@
 
 #include "iavf_types.h"
 
+/* bit indicating whether a 40bit timestamp is valid */
+#define IAVF_PTP_40B_TSTAMP_VALID	BIT(24)
+
 #if IS_ENABLED(CONFIG_PTP_1588_CLOCK)
 void iavf_ptp_init(struct iavf_adapter *adapter);
 void iavf_ptp_release(struct iavf_adapter *adapter);
@@ -15,6 +18,7 @@ void iavf_virtchnl_send_ptp_cmd(struct iavf_adapter *adapter);
 int iavf_ptp_set_ts_config(struct iavf_adapter *adapter,
 			   struct kernel_hwtstamp_config *config,
 			   struct netlink_ext_ack *extack);
+u64 iavf_ptp_extend_32b_timestamp(u64 cached_phc_time, u32 in_tstamp);
 #else /* IS_ENABLED(CONFIG_PTP_1588_CLOCK) */
 static inline void iavf_ptp_init(struct iavf_adapter *adapter) { }
 static inline void iavf_ptp_release(struct iavf_adapter *adapter) { }
@@ -32,5 +36,12 @@ static inline int iavf_ptp_set_ts_config(struct iavf_adapter *adapter,
 {
 	return -1;
 }
+
+static inline u64 iavf_ptp_extend_32b_timestamp(u64 cached_phc_time,
+						u32 in_tstamp)
+{
+	return 0;
+}
+
 #endif /* IS_ENABLED(CONFIG_PTP_1588_CLOCK) */
 #endif /* _IAVF_PTP_H_ */
diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
index 283997b8a777..422312b8b54a 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
@@ -8,6 +8,7 @@
 #include "iavf.h"
 #include "iavf_trace.h"
 #include "iavf_prototype.h"
+#include "iavf_ptp.h"
 
 /**
  * iavf_is_descriptor_done - tests DD bit in Rx descriptor
@@ -1076,6 +1077,45 @@ static void iavf_flex_rx_hash(const struct iavf_ring *ring, __le64 qw1,
 	}
 }
 
+/**
+ * iavf_flex_rx_tstamp - Capture Rx timestamp from the descriptor
+ * @rx_ring: descriptor ring
+ * @qw2: quad word 2 of descriptor
+ * @qw3: quad word 3 of descriptor
+ * @skb: skb currently being received
+ *
+ * Read the Rx timestamp value from the descriptor and pass it to the stack.
+ *
+ * This function only operates on the VIRTCHNL_RXDID_2_FLEX_SQ_NIC flexible
+ * descriptor writeback format.
+ */
+static void iavf_flex_rx_tstamp(const struct iavf_ring *rx_ring, __le64 qw2,
+				__le64 qw3, struct sk_buff *skb)
+{
+	u32 tstamp;
+	u64 ns;
+
+	/* Skip processing if timestamps aren't enabled */
+	if (!(rx_ring->flags & IAVF_TXRX_FLAGS_HW_TSTAMP))
+		return;
+
+	/* Check if this Rx descriptor has a valid timestamp */
+	if (!le64_get_bits(qw2, IAVF_PTP_40B_TSTAMP_VALID))
+		return;
+
+	/* the ts_low field only contains the valid bit and sub-nanosecond
+	 * precision, so we don't need to extract it.
+	 */
+	tstamp = le64_get_bits(qw3, IAVF_RXD_FLEX_QW3_TSTAMP_HIGH_M);
+
+	ns = iavf_ptp_extend_32b_timestamp(rx_ring->ptp->cached_phc_time,
+					   tstamp);
+
+	*skb_hwtstamps(skb) = (struct skb_shared_hwtstamps) {
+		.hwtstamp = ns_to_ktime(ns),
+	};
+}
+
 /**
  * iavf_process_skb_fields - Populate skb header fields from Rx descriptor
  * @rx_ring: rx descriptor ring packet is being transacted on
@@ -1097,11 +1137,14 @@ static void iavf_process_skb_fields(const struct iavf_ring *rx_ring,
 	struct libeth_rx_pt decoded_pt;
 	__le64 qw0 = rx_desc->qw0;
 	__le64 qw1 = rx_desc->qw1;
+	__le64 qw2 = rx_desc->qw2;
+	__le64 qw3 = rx_desc->qw3;
 
 	decoded_pt = libie_rx_pt_parse(ptype);
 
 	if (flex) {
 		iavf_flex_rx_hash(rx_ring, qw1, skb, decoded_pt);
+		iavf_flex_rx_tstamp(rx_ring, qw2, qw3, skb);
 		csum_bits = iavf_flex_rx_csum(rx_ring->vsi, le64_to_cpu(qw1),
 					      decoded_pt);
 	} else {
diff --git a/drivers/net/ethernet/intel/iavf/iavf_type.h b/drivers/net/ethernet/intel/iavf/iavf_type.h
index e62a8a0067ea..f9e1319620f4 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_type.h
+++ b/drivers/net/ethernet/intel/iavf/iavf_type.h
@@ -285,6 +285,7 @@ struct iavf_rx_desc {
 /* L2 Tag 2 Presence */
 #define IAVF_RXD_FLEX_L2TAG2P_M			BIT(11)
 	aligned_le64 qw3;
+#define IAVF_RXD_FLEX_QW3_TSTAMP_HIGH_M		GENMASK_ULL(63, 32)
 } __aligned(4 * sizeof(__le64));
 static_assert(sizeof(struct iavf_rx_desc) == 32);
 
