1 files changed, 560 insertions, 128 deletions

diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c
index 69617d2c1be2..b7b46d863bee 100644
--- a/drivers/net/ethernet/intel/igc/igc_ptp.c
+++ b/drivers/net/ethernet/intel/igc/igc_ptp.c
@@ -9,13 +9,18 @@
 #include <linux/ptp_classify.h>
 #include <linux/clocksource.h>
 #include <linux/ktime.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include <net/xdp_sock_drv.h>
 
 #define INCVALUE_MASK		0x7fffffff
 #define ISGN			0x80000000
 
-#define IGC_SYSTIM_OVERFLOW_PERIOD	(HZ * 60 * 9)
 #define IGC_PTP_TX_TIMEOUT		(HZ * 15)
 
+#define IGC_PTM_STAT_SLEEP		2
+#define IGC_PTM_STAT_TIMEOUT		100
+
 /* SYSTIM read access for I225 */
 void igc_ptp_read(struct igc_adapter *adapter, struct timespec64 *ts)
 {
@@ -252,13 +257,6 @@ static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 
 	switch (rq->type) {
 	case PTP_CLK_REQ_EXTTS:
-		/* Reject requests with unsupported flags */
-		if (rq->extts.flags & ~(PTP_ENABLE_FEATURE |
-					PTP_RISING_EDGE |
-					PTP_FALLING_EDGE |
-					PTP_STRICT_FLAGS))
-			return -EOPNOTSUPP;
-
 		/* Reject requests failing to enable both edges. */
 		if ((rq->extts.flags & PTP_STRICT_FLAGS) &&
 		    (rq->extts.flags & PTP_ENABLE_FEATURE) &&
@@ -295,10 +293,6 @@ static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 		return 0;
 
 	case PTP_CLK_REQ_PEROUT:
-		/* Reject requests with unsupported flags */
-		if (rq->perout.flags)
-			return -EOPNOTSUPP;
-
 		if (on) {
 			pin = ptp_find_pin(igc->ptp_clock, PTP_PF_PEROUT,
 					   rq->perout.index);
@@ -318,7 +312,7 @@ static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 		ts = ns_to_timespec64(ns);
 		if (rq->perout.index == 1) {
 			if (use_freq) {
-				tsauxc_mask = IGC_TSAUXC_EN_CLK1;
+				tsauxc_mask = IGC_TSAUXC_EN_CLK1 | IGC_TSAUXC_ST1;
 				tsim_mask = 0;
 			} else {
 				tsauxc_mask = IGC_TSAUXC_EN_TT1;
@@ -329,7 +323,7 @@ static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 			freqout = IGC_FREQOUT1;
 		} else {
 			if (use_freq) {
-				tsauxc_mask = IGC_TSAUXC_EN_CLK0;
+				tsauxc_mask = IGC_TSAUXC_EN_CLK0 | IGC_TSAUXC_ST0;
 				tsim_mask = 0;
 			} else {
 				tsauxc_mask = IGC_TSAUXC_EN_TT0;
@@ -343,23 +337,44 @@ static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 		tsauxc = rd32(IGC_TSAUXC);
 		tsim = rd32(IGC_TSIM);
 		if (rq->perout.index == 1) {
-			tsauxc &= ~(IGC_TSAUXC_EN_TT1 | IGC_TSAUXC_EN_CLK1);
+			tsauxc &= ~(IGC_TSAUXC_EN_TT1 | IGC_TSAUXC_EN_CLK1 |
+				    IGC_TSAUXC_ST1);
 			tsim &= ~IGC_TSICR_TT1;
 		} else {
-			tsauxc &= ~(IGC_TSAUXC_EN_TT0 | IGC_TSAUXC_EN_CLK0);
+			tsauxc &= ~(IGC_TSAUXC_EN_TT0 | IGC_TSAUXC_EN_CLK0 |
+				    IGC_TSAUXC_ST0);
 			tsim &= ~IGC_TSICR_TT0;
 		}
 		if (on) {
+			struct timespec64 safe_start;
 			int i = rq->perout.index;
 
 			igc_pin_perout(igc, i, pin, use_freq);
-			igc->perout[i].start.tv_sec = rq->perout.start.sec;
+			igc_ptp_read(igc, &safe_start);
+
+			/* PPS output start time is triggered by Target time(TT)
+			 * register. Programming any past time value into TT
+			 * register will cause PPS to never start. Need to make
+			 * sure we program the TT register a time ahead in
+			 * future. There isn't a stringent need to fire PPS out
+			 * right away. Adding +2 seconds should take care of
+			 * corner cases. Let's say if the SYSTIML is close to
+			 * wrap up and the timer keeps ticking as we program the
+			 * register, adding +2seconds is safe bet.
+			 */
+			safe_start.tv_sec += 2;
+
+			if (rq->perout.start.sec < safe_start.tv_sec)
+				igc->perout[i].start.tv_sec = safe_start.tv_sec;
+			else
+				igc->perout[i].start.tv_sec = rq->perout.start.sec;
 			igc->perout[i].start.tv_nsec = rq->perout.start.nsec;
 			igc->perout[i].period.tv_sec = ts.tv_sec;
 			igc->perout[i].period.tv_nsec = ts.tv_nsec;
-			wr32(trgttimh, rq->perout.start.sec);
+			wr32(trgttimh, (u32)igc->perout[i].start.tv_sec);
 			/* For now, always select timer 0 as source. */
-			wr32(trgttiml, rq->perout.start.nsec | IGC_TT_IO_TIMER_SEL_SYSTIM0);
+			wr32(trgttiml, (u32)(igc->perout[i].start.tv_nsec |
+					     IGC_TT_IO_TIMER_SEL_SYSTIM0));
 			if (use_freq)
 				wr32(freqout, ns);
 			tsauxc |= tsauxc_mask;
@@ -411,10 +426,12 @@ static int igc_ptp_verify_pin(struct ptp_clock_info *ptp, unsigned int pin,
  *
  * We need to convert the system time value stored in the RX/TXSTMP registers
  * into a hwtstamp which can be used by the upper level timestamping functions.
+ *
+ * Returns 0 on success.
  **/
-static void igc_ptp_systim_to_hwtstamp(struct igc_adapter *adapter,
-				       struct skb_shared_hwtstamps *hwtstamps,
-				       u64 systim)
+static int igc_ptp_systim_to_hwtstamp(struct igc_adapter *adapter,
+				      struct skb_shared_hwtstamps *hwtstamps,
+				      u64 systim)
 {
 	switch (adapter->hw.mac.type) {
 	case igc_i225:
@@ -424,19 +441,18 @@ static void igc_ptp_systim_to_hwtstamp(struct igc_adapter *adapter,
 						systim & 0xFFFFFFFF);
 		break;
 	default:
-		break;
+		return -EINVAL;
 	}
+	return 0;
 }
 
 /**
  * igc_ptp_rx_pktstamp - Retrieve timestamp from Rx packet buffer
  * @adapter: Pointer to adapter the packet buffer belongs to
- * @buf: Pointer to packet buffer
+ * @buf: Pointer to start of timestamp in HW format (2 32-bit words)
  *
- * This function retrieves the timestamp saved in the beginning of packet
- * buffer. While two timestamps are available, one in timer0 reference and the
- * other in timer1 reference, this function considers only the timestamp in
- * timer0 reference.
+ * This function retrieves and converts the timestamp stored at @buf
+ * to ktime_t, adjusting for hardware latencies.
  *
  * Returns timestamp value.
  */
@@ -446,17 +462,8 @@ ktime_t igc_ptp_rx_pktstamp(struct igc_adapter *adapter, __le32 *buf)
 	u32 secs, nsecs;
 	int adjust;
 
-	/* Timestamps are saved in little endian at the beginning of the packet
-	 * buffer following the layout:
-	 *
-	 * DWORD: | 0              | 1              | 2              | 3              |
-	 * Field: | Timer1 SYSTIML | Timer1 SYSTIMH | Timer0 SYSTIML | Timer0 SYSTIMH |
-	 *
-	 * SYSTIML holds the nanoseconds part while SYSTIMH holds the seconds
-	 * part of the timestamp.
-	 */
-	nsecs = le32_to_cpu(buf[2]);
-	secs = le32_to_cpu(buf[3]);
+	nsecs = le32_to_cpu(buf[0]);
+	secs = le32_to_cpu(buf[1]);
 
 	timestamp = ktime_set(secs, nsecs);
 
@@ -514,10 +521,11 @@ static void igc_ptp_enable_rx_timestamp(struct igc_adapter *adapter)
 
 	for (i = 0; i < adapter->num_rx_queues; i++) {
 		val = rd32(IGC_SRRCTL(i));
-		/* FIXME: For now, only support retrieving RX timestamps from
-		 * timer 0.
+		/* Enable retrieving timestamps from timer 0, the
+		 * "adjustable clock" and timer 1 the "free running
+		 * clock".
 		 */
-		val |= IGC_SRRCTL_TIMER1SEL(0) | IGC_SRRCTL_TIMER0SEL(0) |
+		val |= IGC_SRRCTL_TIMER1SEL(1) | IGC_SRRCTL_TIMER0SEL(0) |
 		       IGC_SRRCTL_TIMESTAMP;
 		wr32(IGC_SRRCTL(i), val);
 	}
@@ -527,9 +535,63 @@ static void igc_ptp_enable_rx_timestamp(struct igc_adapter *adapter)
 	wr32(IGC_TSYNCRXCTL, val);
 }
 
+static void igc_ptp_free_tx_buffer(struct igc_adapter *adapter,
+				   struct igc_tx_timestamp_request *tstamp)
+{
+	if (tstamp->buffer_type == IGC_TX_BUFFER_TYPE_XSK) {
+		/* Release the transmit completion */
+		tstamp->xsk_tx_buffer->xsk_pending_ts = false;
+
+		/* Note: tstamp->skb and tstamp->xsk_tx_buffer are in union.
+		 * By setting tstamp->xsk_tx_buffer to NULL, tstamp->skb will
+		 * become NULL as well.
+		 */
+		tstamp->xsk_tx_buffer = NULL;
+		tstamp->buffer_type = 0;
+
+		/* Trigger txrx interrupt for transmit completion */
+		igc_xsk_wakeup(adapter->netdev, tstamp->xsk_queue_index, 0);
+
+		return;
+	}
+
+	dev_kfree_skb_any(tstamp->skb);
+	tstamp->skb = NULL;
+}
+
+static void igc_ptp_clear_tx_tstamp(struct igc_adapter *adapter)
+{
+	unsigned long flags;
+	int i;
+
+	spin_lock_irqsave(&adapter->ptp_tx_lock, flags);
+
+	for (i = 0; i < IGC_MAX_TX_TSTAMP_REGS; i++) {
+		struct igc_tx_timestamp_request *tstamp = &adapter->tx_tstamp[i];
+
+		if (tstamp->skb)
+			igc_ptp_free_tx_buffer(adapter, tstamp);
+	}
+
+	spin_unlock_irqrestore(&adapter->ptp_tx_lock, flags);
+}
+
 static void igc_ptp_disable_tx_timestamp(struct igc_adapter *adapter)
 {
 	struct igc_hw *hw = &adapter->hw;
+	int i;
+
+	/* Clear the flags first to avoid new packets to be enqueued
+	 * for TX timestamping.
+	 */
+	for (i = 0; i < adapter->num_tx_queues; i++) {
+		struct igc_ring *tx_ring = adapter->tx_ring[i];
+
+		clear_bit(IGC_RING_FLAG_TX_HWTSTAMP, &tx_ring->flags);
+	}
+
+	/* Now we can clean the pending TX timestamp requests. */
+	igc_ptp_clear_tx_tstamp(adapter);
 
 	wr32(IGC_TSYNCTXCTL, 0);
 }
@@ -537,12 +599,23 @@ static void igc_ptp_disable_tx_timestamp(struct igc_adapter *adapter)
 static void igc_ptp_enable_tx_timestamp(struct igc_adapter *adapter)
 {
 	struct igc_hw *hw = &adapter->hw;
+	int i;
 
 	wr32(IGC_TSYNCTXCTL, IGC_TSYNCTXCTL_ENABLED | IGC_TSYNCTXCTL_TXSYNSIG);
 
 	/* Read TXSTMP registers to discard any timestamp previously stored. */
 	rd32(IGC_TXSTMPL);
 	rd32(IGC_TXSTMPH);
+
+	/* The hardware is ready to accept TX timestamp requests,
+	 * notify the transmit path.
+	 */
+	for (i = 0; i < adapter->num_tx_queues; i++) {
+		struct igc_ring *tx_ring = adapter->tx_ring[i];
+
+		set_bit(IGC_RING_FLAG_TX_HWTSTAMP, &tx_ring->flags);
+	}
+
 }
 
 /**
@@ -553,12 +626,8 @@ static void igc_ptp_enable_tx_timestamp(struct igc_adapter *adapter)
  * Return: 0 in case of success, negative errno code otherwise.
  */
 static int igc_ptp_set_timestamp_mode(struct igc_adapter *adapter,
-				      struct hwtstamp_config *config)
+				      struct kernel_hwtstamp_config *config)
 {
-	/* reserved for future extensions */
-	if (config->flags)
-		return -EINVAL;
-
 	switch (config->tx_type) {
 	case HWTSTAMP_TX_OFF:
 		igc_ptp_disable_tx_timestamp(adapter);
@@ -598,59 +667,64 @@ static int igc_ptp_set_timestamp_mode(struct igc_adapter *adapter,
 	return 0;
 }
 
-static void igc_ptp_tx_timeout(struct igc_adapter *adapter)
+/* Requires adapter->ptp_tx_lock held by caller. */
+static void igc_ptp_tx_timeout(struct igc_adapter *adapter,
+			       struct igc_tx_timestamp_request *tstamp)
 {
-	struct igc_hw *hw = &adapter->hw;
+	if (tstamp->skb)
+		igc_ptp_free_tx_buffer(adapter, tstamp);
 
-	dev_kfree_skb_any(adapter->ptp_tx_skb);
-	adapter->ptp_tx_skb = NULL;
 	adapter->tx_hwtstamp_timeouts++;
-	clear_bit_unlock(__IGC_PTP_TX_IN_PROGRESS, &adapter->state);
-	/* Clear the tx valid bit in TSYNCTXCTL register to enable interrupt. */
-	rd32(IGC_TXSTMPH);
+
 	netdev_warn(adapter->netdev, "Tx timestamp timeout\n");
 }
 
 void igc_ptp_tx_hang(struct igc_adapter *adapter)
 {
-	bool timeout = time_is_before_jiffies(adapter->ptp_tx_start +
-					      IGC_PTP_TX_TIMEOUT);
+	struct igc_tx_timestamp_request *tstamp;
+	struct igc_hw *hw = &adapter->hw;
+	unsigned long flags;
+	bool found = false;
+	int i;
 
-	if (!test_bit(__IGC_PTP_TX_IN_PROGRESS, &adapter->state))
-		return;
+	spin_lock_irqsave(&adapter->ptp_tx_lock, flags);
 
-	/* If we haven't received a timestamp within the timeout, it is
-	 * reasonable to assume that it will never occur, so we can unlock the
-	 * timestamp bit when this occurs.
-	 */
-	if (timeout) {
-		cancel_work_sync(&adapter->ptp_tx_work);
-		igc_ptp_tx_timeout(adapter);
+	for (i = 0; i < IGC_MAX_TX_TSTAMP_REGS; i++) {
+		tstamp = &adapter->tx_tstamp[i];
+
+		if (!tstamp->skb)
+			continue;
+
+		if (time_is_after_jiffies(tstamp->start + IGC_PTP_TX_TIMEOUT))
+			continue;
+
+		igc_ptp_tx_timeout(adapter, tstamp);
+		found = true;
 	}
+
+	if (found) {
+		/* Reading the high register of the first set of timestamp registers
+		 * clears all the equivalent bits in the TSYNCTXCTL register.
+		 */
+		rd32(IGC_TXSTMPH_0);
+	}
+
+	spin_unlock_irqrestore(&adapter->ptp_tx_lock, flags);
 }
 
-/**
- * igc_ptp_tx_hwtstamp - utility function which checks for TX time stamp
- * @adapter: Board private structure
- *
- * If we were asked to do hardware stamping and such a time stamp is
- * available, then it must have been for this skb here because we only
- * allow only one such packet into the queue.
- */
-static void igc_ptp_tx_hwtstamp(struct igc_adapter *adapter)
+static void igc_ptp_tx_reg_to_stamp(struct igc_adapter *adapter,
+				    struct igc_tx_timestamp_request *tstamp, u64 regval)
 {
-	struct sk_buff *skb = adapter->ptp_tx_skb;
 	struct skb_shared_hwtstamps shhwtstamps;
-	struct igc_hw *hw = &adapter->hw;
+	struct sk_buff *skb;
 	int adjust = 0;
-	u64 regval;
 
-	if (WARN_ON_ONCE(!skb))
+	skb = tstamp->skb;
+	if (!skb)
 		return;
 
-	regval = rd32(IGC_TXSTMPL);
-	regval |= (u64)rd32(IGC_TXSTMPH) << 32;
-	igc_ptp_systim_to_hwtstamp(adapter, &shhwtstamps, regval);
+	if (igc_ptp_systim_to_hwtstamp(adapter, &shhwtstamps, regval))
+		return;
 
 	switch (adapter->link_speed) {
 	case SPEED_10:
@@ -670,86 +744,349 @@ static void igc_ptp_tx_hwtstamp(struct igc_adapter *adapter)
 	shhwtstamps.hwtstamp =
 		ktime_add_ns(shhwtstamps.hwtstamp, adjust);
 
-	/* Clear the lock early before calling skb_tstamp_tx so that
-	 * applications are not woken up before the lock bit is clear. We use
-	 * a copy of the skb pointer to ensure other threads can't change it
-	 * while we're notifying the stack.
-	 */
-	adapter->ptp_tx_skb = NULL;
-	clear_bit_unlock(__IGC_PTP_TX_IN_PROGRESS, &adapter->state);
+	/* Copy the tx hardware timestamp into xdp metadata or skb */
+	if (tstamp->buffer_type == IGC_TX_BUFFER_TYPE_XSK) {
+		struct xsk_buff_pool *xsk_pool;
+
+		xsk_pool = adapter->tx_ring[tstamp->xsk_queue_index]->xsk_pool;
+		if (xsk_pool && xp_tx_metadata_enabled(xsk_pool)) {
+			xsk_tx_metadata_complete(&tstamp->xsk_meta,
+						 &igc_xsk_tx_metadata_ops,
+						 &shhwtstamps.hwtstamp);
+		}
+	} else {
+		skb_tstamp_tx(skb, &shhwtstamps);
+	}
 
-	/* Notify the stack and free the skb after we've unlocked */
-	skb_tstamp_tx(skb, &shhwtstamps);
-	dev_kfree_skb_any(skb);
+	igc_ptp_free_tx_buffer(adapter, tstamp);
 }
 
 /**
- * igc_ptp_tx_work
- * @work: pointer to work struct
+ * igc_ptp_tx_hwtstamp - utility function which checks for TX time stamp
+ * @adapter: Board private structure
+ *
+ * Check against the ready mask for which of the timestamp register
+ * sets are ready to be retrieved, then retrieve that and notify the
+ * rest of the stack.
  *
- * This work function polls the TSYNCTXCTL valid bit to determine when a
- * timestamp has been taken for the current stored skb.
+ * Context: Expects adapter->ptp_tx_lock to be held by caller.
  */
-static void igc_ptp_tx_work(struct work_struct *work)
+static void igc_ptp_tx_hwtstamp(struct igc_adapter *adapter)
 {
-	struct igc_adapter *adapter = container_of(work, struct igc_adapter,
-						   ptp_tx_work);
 	struct igc_hw *hw = &adapter->hw;
-	u32 tsynctxctl;
+	u64 regval;
+	u32 mask;
+	int i;
 
-	if (!test_bit(__IGC_PTP_TX_IN_PROGRESS, &adapter->state))
-		return;
+	mask = rd32(IGC_TSYNCTXCTL) & IGC_TSYNCTXCTL_TXTT_ANY;
+	if (mask & IGC_TSYNCTXCTL_TXTT_0) {
+		regval = rd32(IGC_TXSTMPL);
+		regval |= (u64)rd32(IGC_TXSTMPH) << 32;
+	} else {
+		/* There's a bug in the hardware that could cause
+		 * missing interrupts for TX timestamping. The issue
+		 * is that for new interrupts to be triggered, the
+		 * IGC_TXSTMPH_0 register must be read.
+		 *
+		 * To avoid discarding a valid timestamp that just
+		 * happened at the "wrong" time, we need to confirm
+		 * that there was no timestamp captured, we do that by
+		 * assuming that no two timestamps in sequence have
+		 * the same nanosecond value.
+		 *
+		 * So, we read the "low" register, read the "high"
+		 * register (to latch a new timestamp) and read the
+		 * "low" register again, if "old" and "new" versions
+		 * of the "low" register are different, a valid
+		 * timestamp was captured, we can read the "high"
+		 * register again.
+		 */
+		u32 txstmpl_old, txstmpl_new;
 
-	tsynctxctl = rd32(IGC_TSYNCTXCTL);
-	if (WARN_ON_ONCE(!(tsynctxctl & IGC_TSYNCTXCTL_TXTT_0)))
-		return;
+		txstmpl_old = rd32(IGC_TXSTMPL);
+		rd32(IGC_TXSTMPH);
+		txstmpl_new = rd32(IGC_TXSTMPL);
+
+		if (txstmpl_old == txstmpl_new)
+			goto done;
+
+		regval = txstmpl_new;
+		regval |= (u64)rd32(IGC_TXSTMPH) << 32;
+	}
+
+	igc_ptp_tx_reg_to_stamp(adapter, &adapter->tx_tstamp[0], regval);
+
+done:
+	/* Now that the problematic first register was handled, we can
+	 * use retrieve the timestamps from the other registers
+	 * (starting from '1') with less complications.
+	 */
+	for (i = 1; i < IGC_MAX_TX_TSTAMP_REGS; i++) {
+		struct igc_tx_timestamp_request *tstamp = &adapter->tx_tstamp[i];
+
+		if (!(tstamp->mask & mask))
+			continue;
+
+		regval = rd32(tstamp->regl);
+		regval |= (u64)rd32(tstamp->regh) << 32;
+
+		igc_ptp_tx_reg_to_stamp(adapter, tstamp, regval);
+	}
+}
+
+/**
+ * igc_ptp_tx_tstamp_event
+ * @adapter: board private structure
+ *
+ * Called when a TX timestamp interrupt happens to retrieve the
+ * timestamp and send it up to the socket.
+ */
+void igc_ptp_tx_tstamp_event(struct igc_adapter *adapter)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&adapter->ptp_tx_lock, flags);
 
 	igc_ptp_tx_hwtstamp(adapter);
+
+	spin_unlock_irqrestore(&adapter->ptp_tx_lock, flags);
 }
 
 /**
- * igc_ptp_set_ts_config - set hardware time stamping config
+ * igc_ptp_hwtstamp_set - set hardware time stamping config
  * @netdev: network interface device structure
- * @ifr: interface request data
+ * @config: timestamping configuration structure
+ * @extack: netlink extended ack structure for error reporting
  *
  **/
-int igc_ptp_set_ts_config(struct net_device *netdev, struct ifreq *ifr)
+int igc_ptp_hwtstamp_set(struct net_device *netdev,
+			 struct kernel_hwtstamp_config *config,
+			 struct netlink_ext_ack *extack)
 {
 	struct igc_adapter *adapter = netdev_priv(netdev);
-	struct hwtstamp_config config;
 	int err;
 
-	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
-		return -EFAULT;
-
-	err = igc_ptp_set_timestamp_mode(adapter, &config);
+	err = igc_ptp_set_timestamp_mode(adapter, config);
 	if (err)
 		return err;
 
 	/* save these settings for future reference */
-	memcpy(&adapter->tstamp_config, &config,
-	       sizeof(adapter->tstamp_config));
+	adapter->tstamp_config = *config;
 
-	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
-		-EFAULT : 0;
+	return 0;
 }
 
 /**
- * igc_ptp_get_ts_config - get hardware time stamping config
+ * igc_ptp_hwtstamp_get - get hardware time stamping config
  * @netdev: network interface device structure
- * @ifr: interface request data
+ * @config: timestamping configuration structure
  *
  * Get the hwtstamp_config settings to return to the user. Rather than attempt
  * to deconstruct the settings from the registers, just return a shadow copy
  * of the last known settings.
  **/
-int igc_ptp_get_ts_config(struct net_device *netdev, struct ifreq *ifr)
+int igc_ptp_hwtstamp_get(struct net_device *netdev,
+			 struct kernel_hwtstamp_config *config)
 {
 	struct igc_adapter *adapter = netdev_priv(netdev);
-	struct hwtstamp_config *config = &adapter->tstamp_config;
 
-	return copy_to_user(ifr->ifr_data, config, sizeof(*config)) ?
-		-EFAULT : 0;
+	*config = adapter->tstamp_config;
+
+	return 0;
+}
+
+/* The two conditions below must be met for cross timestamping via
+ * PCIe PTM:
+ *
+ * 1. We have an way to convert the timestamps in the PTM messages
+ *    to something related to the system clocks (right now, only
+ *    X86 systems with support for the Always Running Timer allow that);
+ *
+ * 2. We have PTM enabled in the path from the device to the PCIe root port.
+ */
+static bool igc_is_crosststamp_supported(struct igc_adapter *adapter)
+{
+	if (!IS_ENABLED(CONFIG_X86_TSC))
+		return false;
+
+	/* FIXME: it was noticed that enabling support for PCIe PTM in
+	 * some i225-V models could cause lockups when bringing the
+	 * interface up/down. There should be no downsides to
+	 * disabling crosstimestamping support for i225-V, as it
+	 * doesn't have any PTP support. That way we gain some time
+	 * while root causing the issue.
+	 */
+	if (adapter->pdev->device == IGC_DEV_ID_I225_V)
+		return false;
+
+	return pcie_ptm_enabled(adapter->pdev);
+}
+
+static struct system_counterval_t igc_device_tstamp_to_system(u64 tstamp)
+{
+#if IS_ENABLED(CONFIG_X86_TSC) && !defined(CONFIG_UML)
+	return (struct system_counterval_t) {
+		.cs_id		= CSID_X86_ART,
+		.cycles		= tstamp,
+		.use_nsecs	= true,
+	};
+#else
+	return (struct system_counterval_t) { };
+#endif
+}
+
+static void igc_ptm_log_error(struct igc_adapter *adapter, u32 ptm_stat)
+{
+	struct net_device *netdev = adapter->netdev;
+
+	switch (ptm_stat) {
+	case IGC_PTM_STAT_RET_ERR:
+		netdev_err(netdev, "PTM Error: Root port timeout\n");
+		break;
+	case IGC_PTM_STAT_BAD_PTM_RES:
+		netdev_err(netdev, "PTM Error: Bad response, PTM Response Data expected\n");
+		break;
+	case IGC_PTM_STAT_T4M1_OVFL:
+		netdev_err(netdev, "PTM Error: T4 minus T1 overflow\n");
+		break;
+	case IGC_PTM_STAT_ADJUST_1ST:
+		netdev_err(netdev, "PTM Error: 1588 timer adjusted during first PTM cycle\n");
+		break;
+	case IGC_PTM_STAT_ADJUST_CYC:
+		netdev_err(netdev, "PTM Error: 1588 timer adjusted during non-first PTM cycle\n");
+		break;
+	default:
+		netdev_err(netdev, "PTM Error: Unknown error (%#x)\n", ptm_stat);
+		break;
+	}
+}
+
+/* The PTM lock: adapter->ptm_lock must be held when calling igc_ptm_trigger() */
+static void igc_ptm_trigger(struct igc_hw *hw)
+{
+	u32 ctrl;
+
+	/* To "manually" start the PTM cycle we need to set the
+	 * trigger (TRIG) bit
+	 */
+	ctrl = rd32(IGC_PTM_CTRL);
+	ctrl |= IGC_PTM_CTRL_TRIG;
+	wr32(IGC_PTM_CTRL, ctrl);
+	/* Perform flush after write to CTRL register otherwise
+	 * transaction may not start
+	 */
+	wrfl();
+}
+
+/* The PTM lock: adapter->ptm_lock must be held when calling igc_ptm_reset() */
+static void igc_ptm_reset(struct igc_hw *hw)
+{
+	u32 ctrl;
+
+	ctrl = rd32(IGC_PTM_CTRL);
+	ctrl &= ~IGC_PTM_CTRL_TRIG;
+	wr32(IGC_PTM_CTRL, ctrl);
+	/* Write to clear all status */
+	wr32(IGC_PTM_STAT, IGC_PTM_STAT_ALL);
+}
+
+static int igc_phc_get_syncdevicetime(ktime_t *device,
+				      struct system_counterval_t *system,
+				      void *ctx)
+{
+	struct igc_adapter *adapter = ctx;
+	struct igc_hw *hw = &adapter->hw;
+	u32 stat, t2_curr_h, t2_curr_l;
+	int err, count = 100;
+	ktime_t t1, t2_curr;
+
+	/* Doing this in a loop because in the event of a
+	 * badly timed (ha!) system clock adjustment, we may
+	 * get PTM errors from the PCI root, but these errors
+	 * are transitory. Repeating the process returns valid
+	 * data eventually.
+	 */
+	do {
+		/* Get a snapshot of system clocks to use as historic value. */
+		ktime_get_snapshot(&adapter->snapshot);
+
+		igc_ptm_trigger(hw);
+
+		err = readx_poll_timeout(rd32, IGC_PTM_STAT, stat,
+					 stat, IGC_PTM_STAT_SLEEP,
+					 IGC_PTM_STAT_TIMEOUT);
+		igc_ptm_reset(hw);
+
+		if (err < 0) {
+			netdev_err(adapter->netdev, "Timeout reading IGC_PTM_STAT register\n");
+			return err;
+		}
+
+		if ((stat & IGC_PTM_STAT_VALID) == IGC_PTM_STAT_VALID)
+			break;
+
+		igc_ptm_log_error(adapter, stat);
+	} while (--count);
+
+	if (!count) {
+		netdev_err(adapter->netdev, "Exceeded number of tries for PTM cycle\n");
+		return -ETIMEDOUT;
+	}
+
+	t1 = ktime_set(rd32(IGC_PTM_T1_TIM0_H), rd32(IGC_PTM_T1_TIM0_L));
+
+	t2_curr_l = rd32(IGC_PTM_CURR_T2_L);
+	t2_curr_h = rd32(IGC_PTM_CURR_T2_H);
+
+	/* FIXME: When the register that tells the endianness of the
+	 * PTM registers are implemented, check them here and add the
+	 * appropriate conversion.
+	 */
+	t2_curr_h = swab32(t2_curr_h);
+
+	t2_curr = ((s64)t2_curr_h << 32 | t2_curr_l);
+
+	*device = t1;
+	*system = igc_device_tstamp_to_system(t2_curr);
+
+	return 0;
+}
+
+static int igc_ptp_getcrosststamp(struct ptp_clock_info *ptp,
+				  struct system_device_crosststamp *cts)
+{
+	struct igc_adapter *adapter = container_of(ptp, struct igc_adapter,
+						   ptp_caps);
+	int ret;
+
+	/* This blocks until any in progress PTM transactions complete */
+	mutex_lock(&adapter->ptm_lock);
+
+	ret = get_device_system_crosststamp(igc_phc_get_syncdevicetime,
+					    adapter, &adapter->snapshot, cts);
+	mutex_unlock(&adapter->ptm_lock);
+
+	return ret;
+}
+
+static int igc_ptp_getcyclesx64(struct ptp_clock_info *ptp,
+				struct timespec64 *ts,
+				struct ptp_system_timestamp *sts)
+{
+	struct igc_adapter *igc = container_of(ptp, struct igc_adapter, ptp_caps);
+	struct igc_hw *hw = &igc->hw;
+	unsigned long flags;
+
+	spin_lock_irqsave(&igc->free_timer_lock, flags);
+
+	ptp_read_system_prets(sts);
+	ts->tv_nsec = rd32(IGC_SYSTIML_1);
+	ts->tv_sec = rd32(IGC_SYSTIMH_1);
+	ptp_read_system_postts(sts);
+
+	spin_unlock_irqrestore(&igc->free_timer_lock, flags);
+
+	return 0;
 }
 
 /**
@@ -762,9 +1099,34 @@ int igc_ptp_get_ts_config(struct net_device *netdev, struct ifreq *ifr)
 void igc_ptp_init(struct igc_adapter *adapter)
 {
 	struct net_device *netdev = adapter->netdev;
+	struct igc_tx_timestamp_request *tstamp;
 	struct igc_hw *hw = &adapter->hw;
 	int i;
 
+	tstamp = &adapter->tx_tstamp[0];
+	tstamp->mask = IGC_TSYNCTXCTL_TXTT_0;
+	tstamp->regl = IGC_TXSTMPL_0;
+	tstamp->regh = IGC_TXSTMPH_0;
+	tstamp->flags = 0;
+
+	tstamp = &adapter->tx_tstamp[1];
+	tstamp->mask = IGC_TSYNCTXCTL_TXTT_1;
+	tstamp->regl = IGC_TXSTMPL_1;
+	tstamp->regh = IGC_TXSTMPH_1;
+	tstamp->flags = IGC_TX_FLAGS_TSTAMP_1;
+
+	tstamp = &adapter->tx_tstamp[2];
+	tstamp->mask = IGC_TSYNCTXCTL_TXTT_2;
+	tstamp->regl = IGC_TXSTMPL_2;
+	tstamp->regh = IGC_TXSTMPH_2;
+	tstamp->flags = IGC_TX_FLAGS_TSTAMP_2;
+
+	tstamp = &adapter->tx_tstamp[3];
+	tstamp->mask = IGC_TSYNCTXCTL_TXTT_3;
+	tstamp->regl = IGC_TXSTMPL_3;
+	tstamp->regh = IGC_TXSTMPH_3;
+	tstamp->flags = IGC_TX_FLAGS_TSTAMP_3;
+
 	switch (hw->mac.type) {
 	case igc_i225:
 		for (i = 0; i < IGC_N_SDP; i++) {
@@ -780,22 +1142,33 @@ void igc_ptp_init(struct igc_adapter *adapter)
 		adapter->ptp_caps.adjfine = igc_ptp_adjfine_i225;
 		adapter->ptp_caps.adjtime = igc_ptp_adjtime_i225;
 		adapter->ptp_caps.gettimex64 = igc_ptp_gettimex64_i225;
+		adapter->ptp_caps.getcyclesx64 = igc_ptp_getcyclesx64;
 		adapter->ptp_caps.settime64 = igc_ptp_settime_i225;
 		adapter->ptp_caps.enable = igc_ptp_feature_enable_i225;
 		adapter->ptp_caps.pps = 1;
 		adapter->ptp_caps.pin_config = adapter->sdp_config;
 		adapter->ptp_caps.n_ext_ts = IGC_N_EXTTS;
 		adapter->ptp_caps.n_per_out = IGC_N_PEROUT;
+		adapter->ptp_caps.supported_extts_flags = PTP_RISING_EDGE |
+							  PTP_FALLING_EDGE |
+							  PTP_STRICT_FLAGS;
 		adapter->ptp_caps.n_pins = IGC_N_SDP;
 		adapter->ptp_caps.verify = igc_ptp_verify_pin;
+
+		if (!igc_is_crosststamp_supported(adapter))
+			break;
+
+		adapter->ptp_caps.getcrosststamp = igc_ptp_getcrosststamp;
 		break;
 	default:
 		adapter->ptp_clock = NULL;
 		return;
 	}
 
+	spin_lock_init(&adapter->ptp_tx_lock);
+	spin_lock_init(&adapter->free_timer_lock);
 	spin_lock_init(&adapter->tmreg_lock);
-	INIT_WORK(&adapter->ptp_tx_work, igc_ptp_tx_work);
+	mutex_init(&adapter->ptm_lock);
 
 	adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
 	adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
@@ -808,6 +1181,7 @@ void igc_ptp_init(struct igc_adapter *adapter)
 	if (IS_ERR(adapter->ptp_clock)) {
 		adapter->ptp_clock = NULL;
 		netdev_err(netdev, "ptp_clock_register failed\n");
+		mutex_destroy(&adapter->ptm_lock);
 	} else if (adapter->ptp_clock) {
 		netdev_info(netdev, "PHC added\n");
 		adapter->ptp_flags |= IGC_PTP_ENABLED;
@@ -832,6 +1206,19 @@ static void igc_ptp_time_restore(struct igc_adapter *adapter)
 	igc_ptp_write_i225(adapter, &ts);
 }
 
+static void igc_ptm_stop(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 ctrl;
+
+	mutex_lock(&adapter->ptm_lock);
+	ctrl = rd32(IGC_PTM_CTRL);
+	ctrl &= ~IGC_PTM_CTRL_EN;
+
+	wr32(IGC_PTM_CTRL, ctrl);
+	mutex_unlock(&adapter->ptm_lock);
+}
+
 /**
  * igc_ptp_suspend - Disable PTP work items and prepare for suspend
  * @adapter: Board private structure
@@ -844,12 +1231,12 @@ void igc_ptp_suspend(struct igc_adapter *adapter)
 	if (!(adapter->ptp_flags & IGC_PTP_ENABLED))
 		return;
 
-	cancel_work_sync(&adapter->ptp_tx_work);
-	dev_kfree_skb_any(adapter->ptp_tx_skb);
-	adapter->ptp_tx_skb = NULL;
-	clear_bit_unlock(__IGC_PTP_TX_IN_PROGRESS, &adapter->state);
+	igc_ptp_clear_tx_tstamp(adapter);
 
-	igc_ptp_time_save(adapter);
+	if (pci_device_is_present(adapter->pdev)) {
+		igc_ptp_time_save(adapter);
+		igc_ptm_stop(adapter);
+	}
 }
 
 /**
@@ -860,13 +1247,18 @@ void igc_ptp_suspend(struct igc_adapter *adapter)
  **/
 void igc_ptp_stop(struct igc_adapter *adapter)
 {
+	if (!(adapter->ptp_flags & IGC_PTP_ENABLED))
+		return;
+
 	igc_ptp_suspend(adapter);
 
+	adapter->ptp_flags &= ~IGC_PTP_ENABLED;
 	if (adapter->ptp_clock) {
 		ptp_clock_unregister(adapter->ptp_clock);
 		netdev_info(adapter->netdev, "PHC removed\n");
 		adapter->ptp_flags &= ~IGC_PTP_ENABLED;
 	}
+	mutex_destroy(&adapter->ptm_lock);
 }
 
 /**
@@ -878,21 +1270,59 @@ void igc_ptp_stop(struct igc_adapter *adapter)
 void igc_ptp_reset(struct igc_adapter *adapter)
 {
 	struct igc_hw *hw = &adapter->hw;
+	u32 cycle_ctrl, ctrl, stat;
 	unsigned long flags;
+	u32 timadj;
+
+	if (!(adapter->ptp_flags & IGC_PTP_ENABLED))
+		return;
 
 	/* reset the tstamp_config */
 	igc_ptp_set_timestamp_mode(adapter, &adapter->tstamp_config);
 
+	mutex_lock(&adapter->ptm_lock);
+
 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
 
 	switch (adapter->hw.mac.type) {
 	case igc_i225:
+		timadj = rd32(IGC_TIMADJ);
+		timadj |= IGC_TIMADJ_ADJUST_METH;
+		wr32(IGC_TIMADJ, timadj);
+
 		wr32(IGC_TSAUXC, 0x0);
 		wr32(IGC_TSSDP, 0x0);
 		wr32(IGC_TSIM,
 		     IGC_TSICR_INTERRUPTS |
 		     (adapter->pps_sys_wrap_on ? IGC_TSICR_SYS_WRAP : 0));
 		wr32(IGC_IMS, IGC_IMS_TS);
+
+		if (!igc_is_crosststamp_supported(adapter))
+			break;
+
+		wr32(IGC_PCIE_DIG_DELAY, IGC_PCIE_DIG_DELAY_DEFAULT);
+		wr32(IGC_PCIE_PHY_DELAY, IGC_PCIE_PHY_DELAY_DEFAULT);
+
+		cycle_ctrl = IGC_PTM_CYCLE_CTRL_CYC_TIME(IGC_PTM_CYC_TIME_DEFAULT);
+
+		wr32(IGC_PTM_CYCLE_CTRL, cycle_ctrl);
+
+		ctrl = IGC_PTM_CTRL_EN |
+			IGC_PTM_CTRL_START_NOW |
+			IGC_PTM_CTRL_SHRT_CYC(IGC_PTM_SHORT_CYC_DEFAULT) |
+			IGC_PTM_CTRL_PTM_TO(IGC_PTM_TIMEOUT_DEFAULT);
+
+		wr32(IGC_PTM_CTRL, ctrl);
+
+		/* Force the first cycle to run. */
+		igc_ptm_trigger(hw);
+
+		if (readx_poll_timeout_atomic(rd32, IGC_PTM_STAT, stat,
+					      stat, IGC_PTM_STAT_SLEEP,
+					      IGC_PTM_STAT_TIMEOUT))
+			netdev_err(adapter->netdev, "Timeout reading IGC_PTM_STAT register\n");
+
+		igc_ptm_reset(hw);
 		break;
 	default:
 		/* No work to do. */
@@ -909,5 +1339,7 @@ void igc_ptp_reset(struct igc_adapter *adapter)
 out:
 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
 
+	mutex_unlock(&adapter->ptm_lock);
+
 	wrfl();
 }