net: mvpp2: set the Rx FIFO size depending on the port speeds for PPv2.2

The Rx FIFO size was set to the same value for all ports. This patch
sets it depending on the maximum speed a given port can handle. This is
only working for PPv2.2.
Signed-off-by: NAntoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvpp2.c

@@ -504,8 +504,12 @@
 #define MVPP2_TX_DESC_ALIGN		(MVPP2_DESC_ALIGNED_SIZE - 1)
 
 /* RX FIFO constants */
-#define MVPP2_RX_FIFO_PORT_DATA_SIZE	0x2000
-#define MVPP2_RX_FIFO_PORT_ATTR_SIZE	0x80
+#define MVPP2_RX_FIFO_PORT_DATA_SIZE_32KB	0x8000
+#define MVPP2_RX_FIFO_PORT_DATA_SIZE_8KB	0x2000
+#define MVPP2_RX_FIFO_PORT_DATA_SIZE_4KB	0x1000
+#define MVPP2_RX_FIFO_PORT_ATTR_SIZE_32KB	0x200
+#define MVPP2_RX_FIFO_PORT_ATTR_SIZE_8KB	0x80
+#define MVPP2_RX_FIFO_PORT_ATTR_SIZE_4KB	0x40
 #define MVPP2_RX_FIFO_PORT_MIN_PKT		0x80
 
 /* RX buffer constants */
@@ -7764,9 +7768,42 @@ static void mvpp2_rx_fifo_init(struct mvpp2 *priv)
 
 	for (port = 0; port < MVPP2_MAX_PORTS; port++) {
 		mvpp2_write(priv, MVPP2_RX_DATA_FIFO_SIZE_REG(port),
-			    MVPP2_RX_FIFO_PORT_DATA_SIZE);
+			    MVPP2_RX_FIFO_PORT_DATA_SIZE_4KB);
 		mvpp2_write(priv, MVPP2_RX_ATTR_FIFO_SIZE_REG(port),
-			    MVPP2_RX_FIFO_PORT_ATTR_SIZE);
+			    MVPP2_RX_FIFO_PORT_ATTR_SIZE_4KB);
+	}
+
+	mvpp2_write(priv, MVPP2_RX_MIN_PKT_SIZE_REG,
+		    MVPP2_RX_FIFO_PORT_MIN_PKT);
+	mvpp2_write(priv, MVPP2_RX_FIFO_INIT_REG, 0x1);
+}
+
+static void mvpp22_rx_fifo_init(struct mvpp2 *priv)
+{
+	int port;
+
+	/* The FIFO size parameters are set depending on the maximum speed a
+	 * given port can handle:
+	 * - Port 0: 10Gbps
+	 * - Port 1: 2.5Gbps
+	 * - Ports 2 and 3: 1Gbps
+	 */
+
+	mvpp2_write(priv, MVPP2_RX_DATA_FIFO_SIZE_REG(0),
+		    MVPP2_RX_FIFO_PORT_DATA_SIZE_32KB);
+	mvpp2_write(priv, MVPP2_RX_ATTR_FIFO_SIZE_REG(0),
+		    MVPP2_RX_FIFO_PORT_ATTR_SIZE_32KB);
+
+	mvpp2_write(priv, MVPP2_RX_DATA_FIFO_SIZE_REG(1),
+		    MVPP2_RX_FIFO_PORT_DATA_SIZE_8KB);
+	mvpp2_write(priv, MVPP2_RX_ATTR_FIFO_SIZE_REG(1),
+		    MVPP2_RX_FIFO_PORT_ATTR_SIZE_8KB);
+
+	for (port = 2; port < MVPP2_MAX_PORTS; port++) {
+		mvpp2_write(priv, MVPP2_RX_DATA_FIFO_SIZE_REG(port),
+			    MVPP2_RX_FIFO_PORT_DATA_SIZE_4KB);
+		mvpp2_write(priv, MVPP2_RX_ATTR_FIFO_SIZE_REG(port),
+			    MVPP2_RX_FIFO_PORT_ATTR_SIZE_4KB);
 	}
 
 	mvpp2_write(priv, MVPP2_RX_MIN_PKT_SIZE_REG,
@@ -7870,7 +7907,10 @@ static int mvpp2_init(struct platform_device *pdev, struct mvpp2 *priv)
 	}
 
 	/* Rx Fifo Init */
+	if (priv->hw_version == MVPP21)
 		mvpp2_rx_fifo_init(priv);
+	else
+		mvpp22_rx_fifo_init(priv);
 
 	if (priv->hw_version == MVPP21)
 		writel(MVPP2_EXT_GLOBAL_CTRL_DEFAULT,