[PATCH net-next v5 0/2] net: stmmac: dwxgmac2: timestamp interrupt support + Agilex5 fix

@@ -340,6 +340,18 @@ static int smtg_crosststamp(ktime_t *device, struct system_counterval_t *system,
 	/* Release the mutex */
 	mutex_unlock(&priv->aux_ts_lock);
 
+	/* Wait for the FIFO clear to complete so a stale ATSNS count from
+	 * a previous snapshot cannot satisfy the poll below before the new
+	 * snapshot is latched.
+	 */
+	ret = readl_poll_timeout(ptpaddr + PTP_ACR, acr_value,
+				 !(acr_value & PTP_ACR_ATSFC), 10, 10000);
+	if (ret) {
+		netdev_err(priv->dev, "%s: Failed to clear snapshot FIFO\n",
+			   __func__);
+		return ret;
+	}
+
 	/* Trigger Internal snapshot signal. Create a rising edge by just toggle
 	 * the GPO0 to low and back to high.
 	 */

@@ -349,9 +361,17 @@ static int smtg_crosststamp(ktime_t *device, struct system_counterval_t *system,
 	gpio_value |= XGMAC_GPIO_GPO0;
 	writel(gpio_value, ioaddr + XGMAC_GPIO_STATUS);
 
-	/* Poll for time sync operation done */
-	ret = readl_poll_timeout(priv->ioaddr + XGMAC_INT_STATUS, v,
-				 (v & XGMAC_INT_TSIS), 100, 10000);
+	/* Wait for the auxiliary snapshot to be latched.  TSIS is a
+	 * transient status bit that is set by any MAC timestamp event and
+	 * cleared by reading XGMAC_TIMESTAMP_STATUS, so it is not a
+	 * reliable completion condition.  Poll the persistent ATSNS count
+	 * instead: it is cleared only by setting PTP_ACR_ATSFC, so
+	 * nothing can clear it while we wait, and it reflects exactly the
+	 * snapshot latched by this trigger.
+	 */
+	ret = readl_poll_timeout(ioaddr + XGMAC_TIMESTAMP_STATUS, v,
+				 FIELD_GET(XGMAC_TIMESTAMP_ATSNS_MASK, v),
+				 100, 10000);
 	if (ret) {
 		netdev_err(priv->dev, "%s: Wait for time sync operation timeout\n",
 			   __func__);

@@ -364,8 +384,7 @@ static int smtg_crosststamp(ktime_t *device, struct system_counterval_t *system,
 		.use_nsecs = false,
 	};
 
-	num_snapshot = FIELD_GET(XGMAC_TIMESTAMP_ATSNS_MASK,
-				 readl(ioaddr + XGMAC_TIMESTAMP_STATUS));
+	num_snapshot = FIELD_GET(XGMAC_TIMESTAMP_ATSNS_MASK, v);
 
 	/* Repeat until the timestamps are from the FIFO last segment */
 	for (i = 0; i < num_snapshot; i++) {

@@ -87,7 +87,7 @@
 #define XGMAC_TSIE			BIT(12)
 #define XGMAC_LPIIE			BIT(5)
 #define XGMAC_PMTIE			BIT(4)
-#define XGMAC_INT_DEFAULT_EN		(XGMAC_LPIIE | XGMAC_PMTIE)
+#define XGMAC_INT_DEFAULT_EN		(XGMAC_LPIIE | XGMAC_PMTIE | XGMAC_TSIE)
 #define XGMAC_Qx_TX_FLOW_CTRL(x)	(0x00000070 + (x) * 4)
 #define XGMAC_PT			GENMASK(31, 16)
 #define XGMAC_TFE			BIT(1)

@@ -1154,6 +1154,49 @@ static int dwxgmac2_get_mac_tx_timestamp(struct mac_device_info *hw, u64 *ts)
 	return 0;
 }
 
+void dwxgmac2_timestamp_interrupt(struct stmmac_priv *priv)
+{
+	u32 ts_status, pending_snapshots, acr_value, channel;
+	struct ptp_clock_event event;
+	unsigned long flags;
+	u64 ptp_time;
+	int i;
+
+	/* Read XGMAC_TIMESTAMP_STATUS to get the AUX snapshot
+	 * count.  This read also clears the TSIS bit in
+	 * XGMAC_INT_STATUS.
+	 * TX timestamp polling may have already cleared TSIS
+	 * and AUXTSTRIG, so rely on ATSNS instead.
+	 * TXTSC is cleared by XGMAC_TXTIMESTAMP_SEC, not by
+	 * this register, so there is no conflict.
+	 */
+	ts_status = readl(priv->ioaddr + XGMAC_TIMESTAMP_STATUS);
+
+	if (!(priv->plat->flags & STMMAC_FLAG_EXT_SNAPSHOT_EN))
+		return;
+
+	pending_snapshots = FIELD_GET(XGMAC_TIMESTAMP_ATSNS_MASK, ts_status);
+	if (!pending_snapshots)
+		return;
+
+	acr_value = readl(priv->ptpaddr + PTP_ACR);
+	channel = FIELD_GET(PTP_ACR_MASK, acr_value);
+	if (!channel)
+		return;
+	channel = ilog2(channel);
+
+	for (i = 0; i < pending_snapshots; i++) {
+		read_lock_irqsave(&priv->ptp_lock, flags);
+		stmmac_get_ptptime(priv, priv->ptpaddr, &ptp_time);
+		read_unlock_irqrestore(&priv->ptp_lock, flags);
+
+		event.type = PTP_CLOCK_EXTTS;
+		event.index = channel;
+		event.timestamp = ptp_time;
+		ptp_clock_event(priv->ptp_clock, &event);
+	}
+}
+
 static int dwxgmac2_flex_pps_config(void __iomem *ioaddr, int index,
 				    struct stmmac_pps_cfg *cfg, bool enable,
 				    u32 sub_second_inc, u32 systime_flags)

@@ -258,7 +258,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwxgmac210_dma_ops,
 		.mac = &dwxgmac210_ops,
 		.vlan = &dwxgmac210_vlan_ops,
-		.hwtimestamp = &stmmac_ptp,
+		.hwtimestamp = &dwxgmac2_ptp,
 		.ptp = &stmmac_ptp_clock_ops,
 		.mode = NULL,
 		.tc = &dwmac510_tc_ops,

@@ -280,7 +280,7 @@ static const struct stmmac_hwif_entry {
 		.dma = &dwxgmac210_dma_ops,
 		.mac = &dwxlgmac2_ops,
 		.vlan = &dwxlgmac2_vlan_ops,
-		.hwtimestamp = &stmmac_ptp,
+		.hwtimestamp = &dwxgmac2_ptp,
 		.ptp = &stmmac_ptp_clock_ops,
 		.mode = NULL,
 		.tc = &dwmac510_tc_ops,

@@ -672,6 +672,7 @@ extern const struct stmmac_desc_ops ndesc_ops;
 
 extern const struct stmmac_hwtimestamp stmmac_ptp;
 extern const struct stmmac_hwtimestamp dwmac1000_ptp;
+extern const struct stmmac_hwtimestamp dwxgmac2_ptp;
 
 extern const struct stmmac_mode_ops ring_mode_ops;
 extern const struct stmmac_mode_ops chain_mode_ops;

@@ -277,3 +277,15 @@ const struct stmmac_hwtimestamp dwmac1000_ptp = {
 	.get_ptptime = dwmac1000_get_ptptime,
 	.timestamp_interrupt = dwmac1000_timestamp_interrupt,
 };
+
+const struct stmmac_hwtimestamp dwxgmac2_ptp = {
+	.config_hw_tstamping = config_hw_tstamping,
+	.init_systime = init_systime,
+	.config_sub_second_increment = config_sub_second_increment,
+	.config_addend = config_addend,
+	.adjust_systime = adjust_systime,
+	.get_systime = get_systime,
+	.get_ptptime = get_ptptime,
+	.timestamp_interrupt = dwxgmac2_timestamp_interrupt,
+	.hwtstamp_correct_latency = hwtstamp_correct_latency,
+};

@@ -103,6 +103,7 @@ int dwmac1000_ptp_enable(struct ptp_clock_info *ptp,
 
 void dwmac1000_get_ptptime(void __iomem *ptpaddr, u64 *ptp_time);
 void dwmac1000_timestamp_interrupt(struct stmmac_priv *priv);
+void dwxgmac2_timestamp_interrupt(struct stmmac_priv *priv);
 
 extern const struct ptp_clock_info stmmac_ptp_clock_ops;
 extern const struct ptp_clock_info dwmac1000_ptp_clock_ops;