mvebu: neta: a37xx: Add fixed link support to neta driver

Add support for fixed link to NETA driver.
This feature requreed for proper support of SFP modules
and onboard connected devices like Ethernet switches

Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
Signed-off-by: Terry Zhou <bjzhou@marvell.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Igal Liberman <igall@marvell.com>
Cc: Nadav Haklai <nadavh@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>

drivers/net/mvneta.c

@@ -191,11 +191,16 @@ DECLARE_GLOBAL_DATA_PTR;
 #define MVNETA_GMAC_AUTONEG_CONFIG               0x2c0c
 #define      MVNETA_GMAC_FORCE_LINK_DOWN         BIT(0)
 #define      MVNETA_GMAC_FORCE_LINK_PASS         BIT(1)
+#define      MVNETA_GMAC_FORCE_LINK_UP           (BIT(0) | BIT(1))
+#define      MVNETA_GMAC_IB_BYPASS_AN_EN         BIT(3)
 #define      MVNETA_GMAC_CONFIG_MII_SPEED        BIT(5)
 #define      MVNETA_GMAC_CONFIG_GMII_SPEED       BIT(6)
 #define      MVNETA_GMAC_AN_SPEED_EN             BIT(7)
+#define      MVNETA_GMAC_SET_FC_EN               BIT(8)
+#define      MVNETA_GMAC_ADVERT_FC_EN            BIT(9)
 #define      MVNETA_GMAC_CONFIG_FULL_DUPLEX      BIT(12)
 #define      MVNETA_GMAC_AN_DUPLEX_EN            BIT(13)
+#define      MVNETA_GMAC_SAMPLE_TX_CFG_EN        BIT(15)
 #define MVNETA_MIB_COUNTERS_BASE                 0x3080
 #define      MVNETA_MIB_LATE_COLLISION           0x7c
 #define MVNETA_DA_FILT_SPEC_MCAST                0x3400
@@ -566,6 +571,13 @@ static void mvneta_rxq_buf_size_set(struct mvneta_port *pp,
 	mvreg_write(pp, MVNETA_RXQ_SIZE_REG(rxq->id), val);
 }
 
+static int mvneta_port_is_fixed_link(struct mvneta_port *pp)
+{
+	/* phy_addr is set to invalid value for fixed link */
+	return pp->phyaddr > PHY_MAX_ADDR;
+}
+
+
 /* Start the Ethernet port RX and TX activity */
 static void mvneta_port_up(struct mvneta_port *pp)
 {
@@ -816,10 +828,12 @@ static void mvneta_defaults_set(struct mvneta_port *pp)
 	/* Assign port SDMA configuration */
 	mvreg_write(pp, MVNETA_SDMA_CONFIG, val);
 
-	/* Enable PHY polling in hardware for U-Boot */
-	val = mvreg_read(pp, MVNETA_UNIT_CONTROL);
-	val |= MVNETA_PHY_POLLING_ENABLE;
-	mvreg_write(pp, MVNETA_UNIT_CONTROL, val);
+	/* Enable PHY polling in hardware if not in fixed-link mode */
+	if (!mvneta_port_is_fixed_link(pp)) {
+		val = mvreg_read(pp, MVNETA_UNIT_CONTROL);
+		val |= MVNETA_PHY_POLLING_ENABLE;
+		mvreg_write(pp, MVNETA_UNIT_CONTROL, val);
+	}
 
 	mvneta_set_ucast_table(pp, -1);
 	mvneta_set_special_mcast_table(pp, -1);
@@ -1137,6 +1151,11 @@ static void mvneta_adjust_link(struct udevice *dev)
 	struct phy_device *phydev = pp->phydev;
 	int status_change = 0;
 
+	if (mvneta_port_is_fixed_link(pp)) {
+		debug("Using fixed link, skip link adjust\n");
+		return;
+	}
+
 	if (phydev->link) {
 		if ((pp->speed != phydev->speed) ||
 		    (pp->duplex != phydev->duplex)) {
@@ -1507,28 +1526,54 @@ static int mvneta_start(struct udevice *dev)
 	mvneta_port_power_up(pp, pp->phy_interface);
 
 	if (!pp->init || pp->link == 0) {
-		/* Set phy address of the port */
-		mvreg_write(pp, MVNETA_PHY_ADDR, pp->phyaddr);
-		phydev = phy_connect(pp->bus, pp->phyaddr, dev,
-				     pp->phy_interface);
-
-		pp->phydev = phydev;
-		phy_config(phydev);
-		phy_startup(phydev);
-		if (!phydev->link) {
-			printf("%s: No link.\n", phydev->dev->name);
-			return -1;
-		}
+		if (mvneta_port_is_fixed_link(pp)) {
+			u32 val;
 
-		/* Full init on first call */
-		mvneta_init(dev);
-		pp->init = 1;
-	} else {
-		/* Upon all following calls, this is enough */
-		mvneta_port_up(pp);
-		mvneta_port_enable(pp);
+			pp->init = 1;
+			pp->link = 1;
+			mvneta_init(dev);
+
+			val = MVNETA_GMAC_FORCE_LINK_UP |
+			      MVNETA_GMAC_IB_BYPASS_AN_EN |
+			      MVNETA_GMAC_SET_FC_EN |
+			      MVNETA_GMAC_ADVERT_FC_EN |
+			      MVNETA_GMAC_SAMPLE_TX_CFG_EN;
+
+			if (pp->duplex)
+				val |= MVNETA_GMAC_CONFIG_FULL_DUPLEX;
+
+			if (pp->speed == SPEED_1000)
+				val |= MVNETA_GMAC_CONFIG_GMII_SPEED;
+			else if (pp->speed == SPEED_100)
+				val |= MVNETA_GMAC_CONFIG_MII_SPEED;
+
+			mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG, val);
+		} else {
+			/* Set phy address of the port */
+			mvreg_write(pp, MVNETA_PHY_ADDR, pp->phyaddr);
+
+			phydev = phy_connect(pp->bus, pp->phyaddr, dev,
+					     pp->phy_interface);
+
+			pp->phydev = phydev;
+			phy_config(phydev);
+			phy_startup(phydev);
+			if (!phydev->link) {
+				printf("%s: No link.\n", phydev->dev->name);
+				return -1;
+			}
+
+			/* Full init on first call */
+			mvneta_init(dev);
+			pp->init = 1;
+			return 0;
+		}
 	}
 
+	/* Upon all following calls, this is enough */
+	mvneta_port_up(pp);
+	mvneta_port_enable(pp);
+
 	return 0;
 }
 
@@ -1625,6 +1670,7 @@ static int mvneta_probe(struct udevice *dev)
 	unsigned long addr;
 	void *bd_space;
 	int ret;
+	int fl_node;
 
 	/*
 	 * Allocate buffer area for descs and rx_buffers. This is only
@@ -1657,10 +1703,19 @@ static int mvneta_probe(struct udevice *dev)
 	/* PHY interface is already decoded in mvneta_ofdata_to_platdata() */
 	pp->phy_interface = pdata->phy_interface;
 
-	/* Now read phyaddr from DT */
-	addr = fdtdec_get_int(blob, node, "phy", 0);
-	addr = fdt_node_offset_by_phandle(blob, addr);
-	pp->phyaddr = fdtdec_get_int(blob, addr, "reg", 0);
+	/* fetch 'fixed-link' property from 'neta' node */
+	fl_node = fdt_subnode_offset(blob, node, "fixed-link");
+	if (fl_node != -FDT_ERR_NOTFOUND) {
+		/* set phy_addr to invalid value for fixed link */
+		pp->phyaddr = PHY_MAX_ADDR + 1;
+		pp->duplex = fdtdec_get_bool(blob, fl_node, "full-duplex");
+		pp->speed = fdtdec_get_int(blob, fl_node, "speed", 0);
+	} else {
+		/* Now read phyaddr from DT */
+		addr = fdtdec_get_int(blob, node, "phy", 0);
+		addr = fdt_node_offset_by_phandle(blob, addr);
+		pp->phyaddr = fdtdec_get_int(blob, addr, "reg", 0);
+	}
 
 	bus = mdio_alloc();
 	if (!bus) {