net: mvpp2: Enable proper PHY polling and fix port functionality

Currently, the network interfaces that are not configured by the bootloader
(using e.g. tftp or ping) can detect the link status but are unable to
transmit data.

The network controller has a functionality that allows the hardware to
continuously poll the PHY and directly update the MAC configuration accordingly
(speed, duplex, etc.). However, this doesn't work well with phylib's
software-based polling and updating MAC configuration in the driver's callback.

This commit fixes this issue by:

  1. Setting MVPP2_PHY_AN_STOP_SMI0_MASK in MVPP2_PHY_AN_CFG0_REG in
     mvpp2_init(), which disables the harware polling feature.

  2. Disabling MVPP2_GMAC_PCS_ENABLE_MASK bit in MVPP2_GMAC_CTRL_2_REG in
     mvpp2_port_mii_set() for port types other than SGMII.
Signed-off-by: Marcin Wojtas <mw@semihalf.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvpp2.c

@@ -248,6 +248,8 @@
 /* LMS registers */
 #define MVPP2_SRC_ADDR_MIDDLE			0x24
 #define MVPP2_SRC_ADDR_HIGH			0x28
+#define MVPP2_PHY_AN_CFG0_REG			0x34
+#define     MVPP2_PHY_AN_STOP_SMI0_MASK		BIT(7)
 #define MVPP2_MIB_COUNTERS_BASE(port)		(0x1000 + ((port) >> 1) * \
 						0x400 + (port) * 0x400)
 #define     MVPP2_MIB_LATE_COLLISION		0x7c
@@ -278,6 +280,7 @@
 #define      MVPP2_GMAC_CONFIG_MII_SPEED	BIT(5)
 #define      MVPP2_GMAC_CONFIG_GMII_SPEED	BIT(6)
 #define      MVPP2_GMAC_AN_SPEED_EN		BIT(7)
+#define      MVPP2_GMAC_FC_ADV_EN		BIT(9)
 #define      MVPP2_GMAC_CONFIG_FULL_DUPLEX	BIT(12)
 #define      MVPP2_GMAC_AN_DUPLEX_EN		BIT(13)
 #define MVPP2_GMAC_PORT_FIFO_CFG_1_REG		0x1c
@@ -3809,16 +3812,30 @@ static void mvpp2_interrupts_unmask(void *arg)
 
 static void mvpp2_port_mii_set(struct mvpp2_port *port)
 {
-	u32 reg, val = 0;
+	u32 val;
 
-	if (port->phy_interface == PHY_INTERFACE_MODE_SGMII)
-		val = MVPP2_GMAC_PCS_ENABLE_MASK |
-		      MVPP2_GMAC_INBAND_AN_MASK;
-	else if (port->phy_interface == PHY_INTERFACE_MODE_RGMII)
-		val = MVPP2_GMAC_PORT_RGMII_MASK;
+	val = readl(port->base + MVPP2_GMAC_CTRL_2_REG);
+
+	switch (port->phy_interface) {
+	case PHY_INTERFACE_MODE_SGMII:
+		val |= MVPP2_GMAC_INBAND_AN_MASK;
+		break;
+	case PHY_INTERFACE_MODE_RGMII:
+		val |= MVPP2_GMAC_PORT_RGMII_MASK;
+	default:
+		val &= ~MVPP2_GMAC_PCS_ENABLE_MASK;
+	}
+
+	writel(val, port->base + MVPP2_GMAC_CTRL_2_REG);
+}
+
+static void mvpp2_port_fc_adv_enable(struct mvpp2_port *port)
+{
+	u32 val;
 
-	reg = readl(port->base + MVPP2_GMAC_CTRL_2_REG);
-	writel(reg | val, port->base + MVPP2_GMAC_CTRL_2_REG);
+	val = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+	val |= MVPP2_GMAC_FC_ADV_EN;
+	writel(val, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
 }
 
 static void mvpp2_port_enable(struct mvpp2_port *port)
@@ -5877,6 +5894,7 @@ static void mvpp2_port_power_up(struct mvpp2_port *port)
 {
 	mvpp2_port_mii_set(port);
 	mvpp2_port_periodic_xon_disable(port);
+	mvpp2_port_fc_adv_enable(port);
 	mvpp2_port_reset(port);
 }
 
@@ -6197,6 +6215,7 @@ static int mvpp2_init(struct platform_device *pdev, struct mvpp2 *priv)
 {
 	const struct mbus_dram_target_info *dram_target_info;
 	int err, i;
+	u32 val;
 
 	/* Checks for hardware constraints */
 	if (rxq_number % 4 || (rxq_number > MVPP2_MAX_RXQ) ||
@@ -6210,6 +6229,11 @@ static int mvpp2_init(struct platform_device *pdev, struct mvpp2 *priv)
 	if (dram_target_info)
 		mvpp2_conf_mbus_windows(dram_target_info, priv);
 
+	/* Disable HW PHY polling */
+	val = readl(priv->lms_base + MVPP2_PHY_AN_CFG0_REG);
+	val |= MVPP2_PHY_AN_STOP_SMI0_MASK;
+	writel(val, priv->lms_base + MVPP2_PHY_AN_CFG0_REG);
+
 	/* Allocate and initialize aggregated TXQs */
 	priv->aggr_txqs = devm_kcalloc(&pdev->dev, num_present_cpus(),
 				       sizeof(struct mvpp2_tx_queue),