net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers

Add DW_2500BASEX case in xpcs_get_state( ) to update speed, duplex and pause

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20231027044306.291250-1-Raju.Lakkaraju@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: Raju Lakkaraju

drivers/net/pcs/pcs-xpcs.c

@@ -1090,6 +1090,28 @@ static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs,
 	return 0;
 }
 
+static int xpcs_get_state_2500basex(struct dw_xpcs *xpcs,
+				    struct phylink_link_state *state)
+{
+	int ret;
+
+	ret = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_STS);
+	if (ret < 0) {
+		state->link = 0;
+		return ret;
+	}
+
+	state->link = !!(ret & DW_VR_MII_MMD_STS_LINK_STS);
+	if (!state->link)
+		return 0;
+
+	state->speed = SPEED_2500;
+	state->pause |= MLO_PAUSE_TX | MLO_PAUSE_RX;
+	state->duplex = DUPLEX_FULL;
+
+	return 0;
+}
+
 static void xpcs_get_state(struct phylink_pcs *pcs,
 			   struct phylink_link_state *state)
 {
@@ -1127,6 +1149,13 @@ static void xpcs_get_state(struct phylink_pcs *pcs,
 			       ERR_PTR(ret));
 		}
 		break;
+	case DW_2500BASEX:
+		ret = xpcs_get_state_2500basex(xpcs, state);
+		if (ret) {
+			pr_err("xpcs_get_state_2500basex returned %pe\n",
+			       ERR_PTR(ret));
+		}
+		break;
 	default:
 		return;
 	}

drivers/net/pcs/pcs-xpcs.h

@@ -55,6 +55,8 @@
 /* Clause 37 Defines */
 /* VR MII MMD registers offsets */
 #define DW_VR_MII_MMD_CTRL		0x0000
+#define DW_VR_MII_MMD_STS		0x0001
+#define DW_VR_MII_MMD_STS_LINK_STS	BIT(2)
 #define DW_VR_MII_DIG_CTRL1		0x8000
 #define DW_VR_MII_AN_CTRL		0x8001
 #define DW_VR_MII_AN_INTR_STS		0x8002