net: stmmac: est: Drop frames causing HLBS error

Drop those frames causing HLBS error to avoid HLBS interrupt
flooding and netdev watchdog timeouts due to blocked packets.
Also add HLBS frame drops to taprio stats.

Signed-off-by: Rohan G Thomas <rohan.g.thomas@altera.com>
Reviewed-by: Matthew Gerlach <matthew.gerlach@altera.com>
Signed-off-by: NipaLocal <nipa@local>

Author: rohangt07

drivers/net/ethernet/stmicro/stmmac/common.h

@@ -228,6 +228,7 @@ struct stmmac_extra_stats {
 	unsigned long mtl_est_btrlm;
 	unsigned long max_sdu_txq_drop[MTL_MAX_TX_QUEUES];
 	unsigned long mtl_est_txq_hlbf[MTL_MAX_TX_QUEUES];
+	unsigned long mtl_est_txq_hlbs[MTL_MAX_TX_QUEUES];
 	/* per queue statistics */
 	struct stmmac_txq_stats txq_stats[MTL_MAX_TX_QUEUES];
 	struct stmmac_rxq_stats rxq_stats[MTL_MAX_RX_QUEUES];

drivers/net/ethernet/stmicro/stmmac/stmmac_est.c

@@ -63,7 +63,7 @@ static int est_configure(struct stmmac_priv *priv, struct stmmac_est *cfg,
 			 EST_GMAC5_PTOV_SHIFT;
 	}
 	if (cfg->enable)
-		ctrl |= EST_EEST | EST_SSWL;
+		ctrl |= EST_EEST | EST_SSWL | EST_DFBS;
 	else
 		ctrl &= ~EST_EEST;
 
@@ -109,6 +109,10 @@ static void est_irq_status(struct stmmac_priv *priv, struct net_device *dev,
 
 		x->mtl_est_hlbs++;
 
+		for (i = 0; i < txqcnt; i++)
+			if (value & BIT(i))
+				x->mtl_est_txq_hlbs[i]++;
+
 		/* Clear Interrupt */
 		writel(value, est_addr + EST_SCH_ERR);
 
@@ -131,10 +135,9 @@ static void est_irq_status(struct stmmac_priv *priv, struct net_device *dev,
 
 		x->mtl_est_hlbf++;
 
-		for (i = 0; i < txqcnt; i++) {
+		for (i = 0; i < txqcnt; i++)
 			if (feqn & BIT(i))
 				x->mtl_est_txq_hlbf[i]++;
-		}
 
 		/* Clear Interrupt */
 		writel(feqn, est_addr + EST_FRM_SZ_ERR);

drivers/net/ethernet/stmicro/stmmac/stmmac_est.h

@@ -16,6 +16,7 @@
 #define EST_XGMAC_PTOV_MUL		9
 #define EST_SSWL			BIT(1)
 #define EST_EEST			BIT(0)
+#define EST_DFBS			BIT(5)
 
 #define EST_STATUS			0x00000008
 #define EST_GMAC5_BTRL			GENMASK(11, 8)

drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c

@@ -1080,6 +1080,7 @@ static int tc_taprio_configure(struct stmmac_priv *priv,
 		for (i = 0; i < priv->plat->tx_queues_to_use; i++) {
 			priv->xstats.max_sdu_txq_drop[i] = 0;
 			priv->xstats.mtl_est_txq_hlbf[i] = 0;
+			priv->xstats.mtl_est_txq_hlbs[i] = 0;
 		}
 		mutex_unlock(&priv->est_lock);
 	}
@@ -1097,7 +1098,8 @@ static void tc_taprio_stats(struct stmmac_priv *priv,
 
 	for (i = 0; i < priv->plat->tx_queues_to_use; i++)
 		window_drops += priv->xstats.max_sdu_txq_drop[i] +
-				priv->xstats.mtl_est_txq_hlbf[i];
+				priv->xstats.mtl_est_txq_hlbf[i] +
+				priv->xstats.mtl_est_txq_hlbs[i];
 	qopt->stats.window_drops = window_drops;
 
 	/* Transmission overrun doesn't happen for stmmac, hence always 0 */
@@ -1111,7 +1113,8 @@ static void tc_taprio_queue_stats(struct stmmac_priv *priv,
 	int queue = qopt->queue_stats.queue;
 
 	q_stats->stats.window_drops = priv->xstats.max_sdu_txq_drop[queue] +
-				      priv->xstats.mtl_est_txq_hlbf[queue];
+				      priv->xstats.mtl_est_txq_hlbf[queue] +
+				      priv->xstats.mtl_est_txq_hlbs[queue];
 
 	/* Transmission overrun doesn't happen for stmmac, hence always 0 */
 	q_stats->stats.tx_overruns = 0;