1 files changed, 86 insertions, 50 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 2eb284576336..748195697e5a 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -50,6 +50,13 @@
 #include "dwxgmac2.h"
 #include "hwif.h"
 
+/* As long as the interface is active, we keep the timestamping counter enabled
+ * with fine resolution and binary rollover. This avoid non-monotonic behavior
+ * (clock jumps) when changing timestamping settings at runtime.
+ */
+#define STMMAC_HWTS_ACTIVE	(PTP_TCR_TSENA | PTP_TCR_TSCFUPDT | \
+				 PTP_TCR_TSCTRLSSR)
+
 #define	STMMAC_ALIGN(x)		ALIGN(ALIGN(x, SMP_CACHE_BYTES), 16)
 #define	TSO_MAX_BUFF_SIZE	(SZ_16K - 1)
 
@@ -613,8 +620,6 @@ static int stmmac_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 {
 	struct stmmac_priv *priv = netdev_priv(dev);
 	struct hwtstamp_config config;
-	struct timespec64 now;
-	u64 temp = 0;
 	u32 ptp_v2 = 0;
 	u32 tstamp_all = 0;
 	u32 ptp_over_ipv4_udp = 0;
@@ -623,11 +628,6 @@ static int stmmac_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 	u32 snap_type_sel = 0;
 	u32 ts_master_en = 0;
 	u32 ts_event_en = 0;
-	u32 sec_inc = 0;
-	u32 value = 0;
-	bool xmac;
-
-	xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;
 
 	if (!(priv->dma_cap.time_stamp || priv->adv_ts)) {
 		netdev_alert(priv->dev, "No support for HW time stamping\n");
@@ -789,42 +789,17 @@ static int stmmac_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 	priv->hwts_rx_en = ((config.rx_filter == HWTSTAMP_FILTER_NONE) ? 0 : 1);
 	priv->hwts_tx_en = config.tx_type == HWTSTAMP_TX_ON;
 
-	if (!priv->hwts_tx_en && !priv->hwts_rx_en)
-		stmmac_config_hw_tstamping(priv, priv->ptpaddr, 0);
-	else {
-		value = (PTP_TCR_TSENA | PTP_TCR_TSCFUPDT | PTP_TCR_TSCTRLSSR |
-			 tstamp_all | ptp_v2 | ptp_over_ethernet |
-			 ptp_over_ipv6_udp | ptp_over_ipv4_udp | ts_event_en |
-			 ts_master_en | snap_type_sel);
-		stmmac_config_hw_tstamping(priv, priv->ptpaddr, value);
-
-		/* program Sub Second Increment reg */
-		stmmac_config_sub_second_increment(priv,
-				priv->ptpaddr, priv->plat->clk_ptp_rate,
-				xmac, &sec_inc);
-		temp = div_u64(1000000000ULL, sec_inc);
-
-		/* Store sub second increment and flags for later use */
-		priv->sub_second_inc = sec_inc;
-		priv->systime_flags = value;
-
-		/* calculate default added value:
-		 * formula is :
-		 * addend = (2^32)/freq_div_ratio;
-		 * where, freq_div_ratio = 1e9ns/sec_inc
-		 */
-		temp = (u64)(temp << 32);
-		priv->default_addend = div_u64(temp, priv->plat->clk_ptp_rate);
-		stmmac_config_addend(priv, priv->ptpaddr, priv->default_addend);
-
-		/* initialize system time */
-		ktime_get_real_ts64(&now);
+	priv->systime_flags = STMMAC_HWTS_ACTIVE;
 
-		/* lower 32 bits of tv_sec are safe until y2106 */
-		stmmac_init_systime(priv, priv->ptpaddr,
-				(u32)now.tv_sec, now.tv_nsec);
+	if (priv->hwts_tx_en || priv->hwts_rx_en) {
+		priv->systime_flags |= tstamp_all | ptp_v2 |
+				       ptp_over_ethernet | ptp_over_ipv6_udp |
+				       ptp_over_ipv4_udp | ts_event_en |
+				       ts_master_en | snap_type_sel;
 	}
 
+	stmmac_config_hw_tstamping(priv, priv->ptpaddr, priv->systime_flags);
+
 	memcpy(&priv->tstamp_config, &config, sizeof(config));
 
 	return copy_to_user(ifr->ifr_data, &config,
@@ -853,6 +828,66 @@ static int stmmac_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
 }
 
 /**
+ * stmmac_init_tstamp_counter - init hardware timestamping counter
+ * @priv: driver private structure
+ * @systime_flags: timestamping flags
+ * Description:
+ * Initialize hardware counter for packet timestamping.
+ * This is valid as long as the interface is open and not suspended.
+ * Will be rerun after resuming from suspend, case in which the timestamping
+ * flags updated by stmmac_hwtstamp_set() also need to be restored.
+ */
+int stmmac_init_tstamp_counter(struct stmmac_priv *priv, u32 systime_flags)
+{
+	bool xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;
+	struct timespec64 now;
+	u32 sec_inc = 0;
+	u64 temp = 0;
+	int ret;
+
+	if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp))
+		return -EOPNOTSUPP;
+
+	ret = clk_prepare_enable(priv->plat->clk_ptp_ref);
+	if (ret < 0) {
+		netdev_warn(priv->dev,
+			    "failed to enable PTP reference clock: %pe\n",
+			    ERR_PTR(ret));
+		return ret;
+	}
+
+	stmmac_config_hw_tstamping(priv, priv->ptpaddr, systime_flags);
+	priv->systime_flags = systime_flags;
+
+	/* program Sub Second Increment reg */
+	stmmac_config_sub_second_increment(priv, priv->ptpaddr,
+					   priv->plat->clk_ptp_rate,
+					   xmac, &sec_inc);
+	temp = div_u64(1000000000ULL, sec_inc);
+
+	/* Store sub second increment for later use */
+	priv->sub_second_inc = sec_inc;
+
+	/* calculate default added value:
+	 * formula is :
+	 * addend = (2^32)/freq_div_ratio;
+	 * where, freq_div_ratio = 1e9ns/sec_inc
+	 */
+	temp = (u64)(temp << 32);
+	priv->default_addend = div_u64(temp, priv->plat->clk_ptp_rate);
+	stmmac_config_addend(priv, priv->ptpaddr, priv->default_addend);
+
+	/* initialize system time */
+	ktime_get_real_ts64(&now);
+
+	/* lower 32 bits of tv_sec are safe until y2106 */
+	stmmac_init_systime(priv, priv->ptpaddr, (u32)now.tv_sec, now.tv_nsec);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(stmmac_init_tstamp_counter);
+
+/**
  * stmmac_init_ptp - init PTP
  * @priv: driver private structure
  * Description: this is to verify if the HW supports the PTPv1 or PTPv2.
@@ -862,9 +897,11 @@ static int stmmac_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
 static int stmmac_init_ptp(struct stmmac_priv *priv)
 {
 	bool xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;
+	int ret;
 
-	if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp))
-		return -EOPNOTSUPP;
+	ret = stmmac_init_tstamp_counter(priv, STMMAC_HWTS_ACTIVE);
+	if (ret)
+		return ret;
 
 	priv->adv_ts = 0;
 	/* Check if adv_ts can be enabled for dwmac 4.x / xgmac core */
@@ -3272,10 +3309,6 @@ static int stmmac_hw_setup(struct net_device *dev, bool init_ptp)
 	stmmac_mmc_setup(priv);
 
 	if (init_ptp) {
-		ret = clk_prepare_enable(priv->plat->clk_ptp_ref);
-		if (ret < 0)
-			netdev_warn(priv->dev, "failed to enable PTP reference clock: %d\n", ret);
-
 		ret = stmmac_init_ptp(priv);
 		if (ret == -EOPNOTSUPP)
 			netdev_warn(priv->dev, "PTP not supported by HW\n");
@@ -3769,6 +3802,8 @@ int stmmac_release(struct net_device *dev)
 	struct stmmac_priv *priv = netdev_priv(dev);
 	u32 chan;
 
+	netif_tx_disable(dev);
+
 	if (device_may_wakeup(priv->device))
 		phylink_speed_down(priv->phylink, false);
 	/* Stop and disconnect the PHY */
@@ -5161,12 +5196,13 @@ read_again:
 		if (likely(!(status & rx_not_ls)) &&
 		    (likely(priv->synopsys_id >= DWMAC_CORE_4_00) ||
 		     unlikely(status != llc_snap))) {
-			if (buf2_len)
+			if (buf2_len) {
 				buf2_len -= ETH_FCS_LEN;
-			else
+				len -= ETH_FCS_LEN;
+			} else if (buf1_len) {
 				buf1_len -= ETH_FCS_LEN;
-
-			len -= ETH_FCS_LEN;
+				len -= ETH_FCS_LEN;
+			}
 		}
 
 		if (!skb) {