Patch "net: stmmac: No need to calculate speed divider when offload is disabled" has been added to the 6.9-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    net: stmmac: No need to calculate speed divider when offload is disabled

to the 6.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-stmmac-no-need-to-calculate-speed-divider-when-o.patch
and it can be found in the queue-6.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 880d9ef96cbe0853dcfd147a2b6229c080683eba
Author: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx>
Date:   Mon Jun 17 09:39:22 2024 +0800

    net: stmmac: No need to calculate speed divider when offload is disabled
    
    [ Upstream commit b8c43360f6e424131fa81d3ba8792ad8ff25a09e ]
    
    commit be27b8965297 ("net: stmmac: replace priv->speed with
    the portTransmitRate from the tc-cbs parameters") introduced
    a problem. When deleting, it prompts "Invalid portTransmitRate
    0 (idleSlope - sendSlope)" and exits. Add judgment on cbs.enable.
    Only when offload is enabled, speed divider needs to be calculated.
    
    Fixes: be27b8965297 ("net: stmmac: replace priv->speed with the portTransmitRate from the tc-cbs parameters")
    Signed-off-by: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx>
    Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20240617013922.1035854-1-xiaolei.wang@xxxxxxxxxxxxx
    Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
index b1896379dbab5..7d240a2b54a85 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
@@ -358,24 +358,28 @@ static int tc_setup_cbs(struct stmmac_priv *priv,
 
 	port_transmit_rate_kbps = qopt->idleslope - qopt->sendslope;
 
-	/* Port Transmit Rate and Speed Divider */
-	switch (div_s64(port_transmit_rate_kbps, 1000)) {
-	case SPEED_10000:
-	case SPEED_5000:
-		ptr = 32;
-		break;
-	case SPEED_2500:
-	case SPEED_1000:
-		ptr = 8;
-		break;
-	case SPEED_100:
-		ptr = 4;
-		break;
-	default:
-		netdev_err(priv->dev,
-			   "Invalid portTransmitRate %lld (idleSlope - sendSlope)\n",
-			   port_transmit_rate_kbps);
-		return -EINVAL;
+	if (qopt->enable) {
+		/* Port Transmit Rate and Speed Divider */
+		switch (div_s64(port_transmit_rate_kbps, 1000)) {
+		case SPEED_10000:
+		case SPEED_5000:
+			ptr = 32;
+			break;
+		case SPEED_2500:
+		case SPEED_1000:
+			ptr = 8;
+			break;
+		case SPEED_100:
+			ptr = 4;
+			break;
+		default:
+			netdev_err(priv->dev,
+				   "Invalid portTransmitRate %lld (idleSlope - sendSlope)\n",
+				   port_transmit_rate_kbps);
+			return -EINVAL;
+		}
+	} else {
+		ptr = 0;
 	}
 
 	mode_to_use = priv->plat->tx_queues_cfg[queue].mode_to_use;