Subject: [PATCH net 1/4] net: stmmac: Apply half-duplex-less constraint for DW QoS Eth only

From: Serge Semin <[email-masked]>
Date: Fri, 12 Apr 2024 21:03:14 +0300

There are three DW MAC IP-cores which can have the multiple Tx/Rx queues
enabled:
DW GMAC v3.7+ with AV feature,
DW QoS Eth v4.x/v5.x,
DW XGMAC/XLGMAC
Based on the respective HW databooks, only the DW QoS Eth IP-core doesn't
support the half-duplex link mode in case if more than one queues enabled:

"In multiple queue/channel configurations, for half-duplex operation,
enable only the Q0/CH0 on Tx and Rx. For single queue/channel in
full-duplex operation, any queue/channel can be enabled."

The rest of the IP-cores don't have such constraint. Thus in order to have
the constraint applied for the DW QoS Eth MACs only, let's move the it'
implementation to the respective MAC-capabilities getter and make sure the
getter is called in the queues re-init procedure.

Fixes: b6cfffa7ad92 ("stmmac: fix DMA channel hang in half-duplex mode")
Signed-off-by: Serge Semin <[email-masked]>
---
 .../net/ethernet/stmicro/stmmac/dwmac4_core.c |  7 +++++++
 .../net/ethernet/stmicro/stmmac/stmmac_main.c | 19 +++----------------
 2 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index cef25efbdff9..ec6a13e644b3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -71,6 +71,13 @@ static void dwmac4_core_init(struct mac_device_info *hw,
 static void dwmac4_phylink_get_caps(struct stmmac_priv *priv)
 {
 	priv->phylink_config.mac_capabilities |= MAC_2500FD;
+
+	if (priv->plat->tx_queues_to_use > 1)
+		priv->phylink_config.mac_capabilities &=
+			~(MAC_10HD | MAC_100HD | MAC_1000HD);
+	else
+		priv->phylink_config.mac_capabilities |=
+			(MAC_10HD | MAC_100HD | MAC_1000HD);
 }
 
 static void dwmac4_rx_queue_enable(struct mac_device_info *hw,
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 24cd80490d19..dd58c21b53ee 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1198,17 +1198,6 @@ static int stmmac_init_phy(struct net_device *dev)
 	return ret;
 }
 
-static void stmmac_set_half_duplex(struct stmmac_priv *priv)
-{
-	/* Half-Duplex can only work with single tx queue */
-	if (priv->plat->tx_queues_to_use > 1)
-		priv->phylink_config.mac_capabilities &=
-			~(MAC_10HD | MAC_100HD | MAC_1000HD);
-	else
-		priv->phylink_config.mac_capabilities |=
-			(MAC_10HD | MAC_100HD | MAC_1000HD);
-}
-
 static int stmmac_phy_setup(struct stmmac_priv *priv)
 {
 	struct stmmac_mdio_bus_data *mdio_bus_data;
@@ -1237,10 +1226,7 @@ static int stmmac_phy_setup(struct stmmac_priv *priv)
 				    priv->phylink_config.supported_interfaces);
 
 	priv->phylink_config.mac_capabilities = MAC_ASYM_PAUSE | MAC_SYM_PAUSE |
-						MAC_10FD | MAC_100FD |
-						MAC_1000FD;
-
-	stmmac_set_half_duplex(priv);
+						MAC_10 | MAC_100 | MAC_1000;
 
 	/* Get the MAC specific capabilities */
 	stmmac_mac_phylink_get_caps(priv);
@@ -7355,7 +7341,8 @@ int stmmac_reinit_queues(struct net_device *dev, u32 rx_cnt, u32 tx_cnt)
 			priv->rss.table[i] = ethtool_rxfh_indir_default(i,
 									rx_cnt);
 
-	stmmac_set_half_duplex(priv);
+	stmmac_mac_phylink_get_caps(priv);
+
 	stmmac_napi_add(dev);
 
 	if (netif_running(dev))
-- 
2.43.0