diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index c7c876408d85..aa09b2defcd9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -337,6 +337,12 @@ struct stmmac_priv {
 	int use_riwt;
 	int irq_wake;
 	rwlock_t ptp_lock;
+	/* Serialize PHC changes with a hardware reset; gettime uses ptp_lock. */
+	struct mutex ptp_mutex;
+	bool ptp_blocked;
+	long ptp_scaled_ppm;
+	u32 ptp_perout;
+	u32 ptp_extts;
 	/* Protects auxiliary snapshot registers from concurrent access. */
 	struct mutex aux_ts_lock;
 	wait_queue_head_t tstamp_busy_wait;
@@ -404,6 +410,7 @@ void stmmac_set_ethtool_ops(struct net_device *netdev);
 
 void stmmac_ptp_register(struct stmmac_priv *priv);
 void stmmac_ptp_unregister(struct stmmac_priv *priv);
+int stmmac_ptp_restore(struct stmmac_priv *priv);
 int stmmac_xdp_open(struct net_device *dev);
 void stmmac_xdp_release(struct net_device *dev);
 int stmmac_get_phy_intf_sel(phy_interface_t interface);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 4f3d452c3503..8b0bc7c46df9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -941,6 +941,11 @@ static void stmmac_setup_ptp(struct stmmac_priv *priv)
 {
 	int ret;
 
+	priv->ptp_scaled_ppm = 0;
+	priv->ptp_perout = 0;
+	priv->ptp_extts = 0;
+	priv->ptp_blocked = false;
+
 	ret = clk_prepare_enable(priv->plat->clk_ptp_ref);
 	if (ret < 0)
 		netdev_warn(priv->dev,
@@ -6285,7 +6290,8 @@ static void stmmac_common_interrupt(struct stmmac_priv *priv)
 		for (queue = 0; queue < queues_count; queue++)
 			stmmac_host_mtl_irq_status(priv, priv->hw, queue);
 
-		stmmac_timestamp_interrupt(priv, priv);
+		if (!READ_ONCE(priv->ptp_blocked))
+			stmmac_timestamp_interrupt(priv, priv);
 	}
 }
 
@@ -7696,6 +7702,14 @@ static int stmmac_dl_ts_coarse_set(struct devlink *dl, u32 id,
 {
 	struct stmmac_devlink_priv *dl_priv = devlink_priv(dl);
 	struct stmmac_priv *priv = dl_priv->stmmac_priv;
+	unsigned long flags;
+
+	mutex_lock(&priv->ptp_mutex);
+	if (priv->ptp_blocked) {
+		mutex_unlock(&priv->ptp_mutex);
+		return -EBUSY;
+	}
+	write_lock_irqsave(&priv->ptp_lock, flags);
 
 	priv->tsfupdt_coarse = ctx->val.vbool;
 
@@ -7708,6 +7722,8 @@ static int stmmac_dl_ts_coarse_set(struct devlink *dl, u32 id,
 	 * reconfigure the systime, subsecond increment and addend.
 	 */
 	stmmac_update_subsecond_increment(priv);
+	write_unlock_irqrestore(&priv->ptp_lock, flags);
+	mutex_unlock(&priv->ptp_mutex);
 
 	return 0;
 }
@@ -8048,6 +8064,7 @@ static int __stmmac_dvr_probe(struct device *device,
 
 	mutex_init(&priv->lock);
 	rwlock_init(&priv->ptp_lock);
+	mutex_init(&priv->ptp_mutex);
 
 	stmmac_fpe_init(priv);
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
index 3bfcc9760dce..bc6fe0c87e01 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
@@ -12,6 +12,16 @@
 
 #define PTP_SAFE_TIME_OFFSET_NS	500000
 
+static int stmmac_ptp_begin(struct stmmac_priv *priv)
+{
+	mutex_lock(&priv->ptp_mutex);
+	if (priv->ptp_blocked) {
+		mutex_unlock(&priv->ptp_mutex);
+		return -EBUSY;
+	}
+	return 0;
+}
+
 /**
  * stmmac_adjust_freq
  *
@@ -28,14 +38,21 @@ static int stmmac_adjust_freq(struct ptp_clock_info *ptp, long scaled_ppm)
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	unsigned long flags;
 	u32 addend;
+	int ret;
 
-	addend = adjust_by_scaled_ppm(priv->default_addend, scaled_ppm);
+	ret = stmmac_ptp_begin(priv);
+	if (ret)
+		return ret;
 
 	write_lock_irqsave(&priv->ptp_lock, flags);
-	stmmac_config_addend(priv, priv->ptpaddr, addend);
+	addend = adjust_by_scaled_ppm(priv->default_addend, scaled_ppm);
+	ret = stmmac_config_addend(priv, priv->ptpaddr, addend);
+	if (!ret)
+		priv->ptp_scaled_ppm = scaled_ppm;
 	write_unlock_irqrestore(&priv->ptp_lock, flags);
+	mutex_unlock(&priv->ptp_mutex);
 
-	return 0;
+	return ret;
 }
 
 /**
@@ -57,6 +74,10 @@ static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
 	bool xmac, est_rst = false;
 	int ret;
 
+	ret = stmmac_ptp_begin(priv);
+	if (ret)
+		return ret;
+
 	xmac = dwmac_is_xmac(priv->plat->core_type);
 
 	if (delta < 0) {
@@ -110,6 +131,7 @@ static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
 			netdev_err(priv->dev, "failed to configure EST\n");
 	}
 
+	mutex_unlock(&priv->ptp_mutex);
 	return 0;
 }
 
@@ -128,14 +150,18 @@ static int stmmac_get_time(struct ptp_clock_info *ptp, struct timespec64 *ts)
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	unsigned long flags;
 	u64 ns = 0;
+	int ret = 0;
 
 	read_lock_irqsave(&priv->ptp_lock, flags);
-	stmmac_get_systime(priv, priv->ptpaddr, &ns);
+	if (priv->ptp_blocked)
+		ret = -EBUSY;
+	else
+		stmmac_get_systime(priv, priv->ptpaddr, &ns);
 	read_unlock_irqrestore(&priv->ptp_lock, flags);
 
 	*ts = ns_to_timespec64(ns);
 
-	return 0;
+	return ret;
 }
 
 /**
@@ -153,25 +179,34 @@ static int stmmac_set_time(struct ptp_clock_info *ptp,
 	struct stmmac_priv *priv =
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	unsigned long flags;
+	int ret;
+
+	ret = stmmac_ptp_begin(priv);
+	if (ret)
+		return ret;
 
 	write_lock_irqsave(&priv->ptp_lock, flags);
-	stmmac_init_systime(priv, priv->ptpaddr, ts->tv_sec, ts->tv_nsec);
+	ret = stmmac_init_systime(priv, priv->ptpaddr, ts->tv_sec, ts->tv_nsec);
 	write_unlock_irqrestore(&priv->ptp_lock, flags);
+	mutex_unlock(&priv->ptp_mutex);
 
-	return 0;
+	return ret;
 }
 
-static int stmmac_enable(struct ptp_clock_info *ptp,
-			 struct ptp_clock_request *rq, int on)
+static int __stmmac_enable(struct ptp_clock_info *ptp,
+			   struct ptp_clock_request *rq, int on)
 {
 	struct stmmac_priv *priv =
 	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
 	void __iomem *ptpaddr = priv->ptpaddr;
-	struct stmmac_pps_cfg *cfg;
+	struct stmmac_pps_cfg pps, saved, *cfg = &pps;
 	int ret = -EOPNOTSUPP;
 	unsigned long flags;
 	u32 acr_value;
 
+	if (priv->plat->core_type == DWMAC_CORE_GMAC)
+		return dwmac1000_ptp_enable(ptp, rq, on);
+
 	switch (rq->type) {
 	case PTP_CLK_REQ_PEROUT: {
 		struct timespec64 curr_time;
@@ -182,8 +217,6 @@ static int stmmac_enable(struct ptp_clock_info *ptp,
 		if (rq->perout.flags)
 			return -EOPNOTSUPP;
 
-		cfg = &priv->pps[rq->perout.index];
-
 		cfg->start.tv_sec = rq->perout.start.sec;
 		cfg->start.tv_nsec = rq->perout.start.nsec;
 
@@ -213,6 +246,7 @@ static int stmmac_enable(struct ptp_clock_info *ptp,
 
 		cfg->period.tv_sec = rq->perout.period.sec;
 		cfg->period.tv_nsec = rq->perout.period.nsec;
+		saved = *cfg;
 
 		write_lock_irqsave(&priv->ptp_lock, flags);
 		ret = stmmac_flex_pps_config(priv, priv->ioaddr,
@@ -220,6 +254,9 @@ static int stmmac_enable(struct ptp_clock_info *ptp,
 					     priv->sub_second_inc,
 					     priv->systime_flags);
 		write_unlock_irqrestore(&priv->ptp_lock, flags);
+		/* Some cores convert cfg->start to binary rollover units. */
+		if (!ret)
+			priv->pps[rq->perout.index] = saved;
 		break;
 	}
 	case PTP_CLK_REQ_EXTTS: {
@@ -265,6 +302,64 @@ static int stmmac_enable(struct ptp_clock_info *ptp,
 	return ret;
 }
 
+static int stmmac_enable(struct ptp_clock_info *ptp,
+			 struct ptp_clock_request *rq, int on)
+{
+	struct stmmac_priv *priv =
+		container_of(ptp, struct stmmac_priv, ptp_clock_ops);
+	int ret;
+
+	ret = stmmac_ptp_begin(priv);
+	if (ret)
+		return ret;
+	ret = __stmmac_enable(ptp, rq, on);
+	if (!ret) {
+		if (rq->type == PTP_CLK_REQ_PEROUT) {
+			if (on)
+				priv->ptp_perout |= BIT(rq->perout.index);
+			else
+				priv->ptp_perout &= ~BIT(rq->perout.index);
+		} else if (rq->type == PTP_CLK_REQ_EXTTS) {
+			priv->ptp_extts = on ? BIT(rq->extts.index) : 0;
+		}
+	}
+	mutex_unlock(&priv->ptp_mutex);
+	return ret;
+}
+
+/* Called with ptp_mutex held and PHC access blocked across the MAC reset. */
+int stmmac_ptp_restore(struct stmmac_priv *priv)
+{
+	struct ptp_clock_request rq = { .type = PTP_CLK_REQ_EXTTS };
+	unsigned long flags;
+	u64 ns = 0, period;
+	u32 addend;
+	int i, ret;
+
+	write_lock_irqsave(&priv->ptp_lock, flags);
+	addend = adjust_by_scaled_ppm(priv->default_addend, priv->ptp_scaled_ppm);
+	ret = stmmac_config_addend(priv, priv->ptpaddr, addend);
+	for (i = 0; !ret && i < STMMAC_PPS_MAX; i++) {
+		struct stmmac_pps_cfg cfg = priv->pps[i];
+
+		if (!(priv->ptp_perout & BIT(i)))
+			continue;
+		stmmac_get_systime(priv, priv->ptpaddr, &ns);
+		period = timespec64_to_ns(&cfg.period);
+		/* Retain phase, but move an expired target into the future. */
+		cfg.start = stmmac_calc_tas_basetime(timespec64_to_ktime(cfg.start),
+						     ns + PTP_SAFE_TIME_OFFSET_NS, period);
+		ret = stmmac_flex_pps_config(priv, priv->ioaddr, i, &cfg, true,
+					     priv->sub_second_inc, priv->systime_flags);
+	}
+	write_unlock_irqrestore(&priv->ptp_lock, flags);
+	if (ret || !priv->ptp_extts)
+		return ret;
+
+	rq.extts.index = __ffs(priv->ptp_extts);
+	return __stmmac_enable(&priv->ptp_clock_ops, &rq, 1);
+}
+
 /**
  * stmmac_get_syncdevicetime
  * @device: current device time
@@ -287,9 +382,15 @@ static int stmmac_getcrosststamp(struct ptp_clock_info *ptp,
 {
 	struct stmmac_priv *priv =
 		container_of(ptp, struct stmmac_priv, ptp_clock_ops);
+	int ret;
 
-	return get_device_system_crosststamp(stmmac_get_syncdevicetime,
-					     priv, NULL, xtstamp);
+	ret = stmmac_ptp_begin(priv);
+	if (ret)
+		return ret;
+	ret = get_device_system_crosststamp(stmmac_get_syncdevicetime,
+					    priv, NULL, xtstamp);
+	mutex_unlock(&priv->ptp_mutex);
+	return ret;
 }
 
 /* structure describing a PTP hardware clock */
@@ -323,7 +424,7 @@ const struct ptp_clock_info dwmac1000_ptp_clock_ops = {
 	.adjtime = stmmac_adjust_time,
 	.gettime64 = stmmac_get_time,
 	.settime64 = stmmac_set_time,
-	.enable = dwmac1000_ptp_enable,
+	.enable = stmmac_enable,
 };
 
 /**