3 files changed, 53 insertions, 28 deletions

diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h b/drivers/net/ethernet/xilinx/xilinx_axienet.h
index f9078bd7f86f..f240ff1b7296 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet.h
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h
@@ -418,6 +418,9 @@ struct axienet_local {
 	/* Connection to PHY device */
 	struct device_node *phy_node;
 
+	/* Clock for AXI bus */
+	struct clk *clk;
+
 	/* MDIO bus data */
 	struct mii_bus *mii_bus;	/* MII bus reference */
 
@@ -502,7 +505,7 @@ static inline void axienet_iow(struct axienet_local *lp, off_t offset,
 }
 
 /* Function prototypes visible in xilinx_axienet_mdio.c for other files */
-int axienet_mdio_setup(struct axienet_local *lp, struct device_node *np);
+int axienet_mdio_setup(struct axienet_local *lp);
 int axienet_mdio_wait_until_ready(struct axienet_local *lp);
 void axienet_mdio_teardown(struct axienet_local *lp);
 
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index ffbd4d762534..42b343cb3e2b 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -21,6 +21,7 @@
  *  - Add support for extended VLAN support.
  */
 
+#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/etherdevice.h>
 #include <linux/module.h>
@@ -1611,9 +1612,24 @@ static int axienet_probe(struct platform_device *pdev)
 
 	lp->phy_node = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
 	if (lp->phy_node) {
-		ret = axienet_mdio_setup(lp, pdev->dev.of_node);
+		lp->clk = devm_clk_get(&pdev->dev, NULL);
+		if (IS_ERR(lp->clk)) {
+			dev_warn(&pdev->dev, "Failed to get clock: %ld\n",
+				 PTR_ERR(lp->clk));
+			lp->clk = NULL;
+		} else {
+			ret = clk_prepare_enable(lp->clk);
+			if (ret) {
+				dev_err(&pdev->dev, "Unable to enable clock: %d\n",
+					ret);
+				goto free_netdev;
+			}
+		}
+
+		ret = axienet_mdio_setup(lp);
 		if (ret)
-			dev_warn(&pdev->dev, "error registering MDIO bus\n");
+			dev_warn(&pdev->dev,
+				 "error registering MDIO bus: %d\n", ret);
 	}
 
 	ret = register_netdev(lp->ndev);
@@ -1638,6 +1654,9 @@ static int axienet_remove(struct platform_device *pdev)
 	axienet_mdio_teardown(lp);
 	unregister_netdev(ndev);
 
+	if (lp->clk)
+		clk_disable_unprepare(lp->clk);
+
 	of_node_put(lp->phy_node);
 	lp->phy_node = NULL;
 
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c b/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c
index 665ae1d16f1e..cce0dc42583e 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c
@@ -8,6 +8,7 @@
  * Copyright (c) 2010 - 2012 Xilinx, Inc. All rights reserved.
  */
 
+#include <linux/clk.h>
 #include <linux/of_address.h>
 #include <linux/of_mdio.h>
 #include <linux/jiffies.h>
@@ -16,7 +17,7 @@
 #include "xilinx_axienet.h"
 
 #define MAX_MDIO_FREQ		2500000 /* 2.5 MHz */
-#define DEFAULT_CLOCK_DIVISOR	XAE_MDIO_DIV_DFT
+#define DEFAULT_HOST_CLOCK	150000000 /* 150 MHz */
 
 /* Wait till MDIO interface is ready to accept a new transaction.*/
 int axienet_mdio_wait_until_ready(struct axienet_local *lp)
@@ -114,7 +115,6 @@ static int axienet_mdio_write(struct mii_bus *bus, int phy_id, int reg,
 /**
  * axienet_mdio_setup - MDIO setup function
  * @lp:		Pointer to axienet local data structure.
- * @np:		Pointer to device node
  *
  * Return:	0 on success, -ETIMEDOUT on a timeout, -ENOMEM when
  *		mdiobus_alloc (to allocate memory for mii bus structure) fails.
@@ -122,13 +122,37 @@ static int axienet_mdio_write(struct mii_bus *bus, int phy_id, int reg,
  * Sets up the MDIO interface by initializing the MDIO clock and enabling the
  * MDIO interface in hardware. Register the MDIO interface.
  **/
-int axienet_mdio_setup(struct axienet_local *lp, struct device_node *np)
+int axienet_mdio_setup(struct axienet_local *lp)
 {
 	int ret;
 	u32 clk_div, host_clock;
 	struct mii_bus *bus;
 	struct device_node *mdio_node;
-	struct device_node *np1;
+
+	if (lp->clk) {
+		host_clock = clk_get_rate(lp->clk);
+	} else {
+		struct device_node *np1;
+
+		/* Legacy fallback: detect CPU clock frequency and use as AXI
+		 * bus clock frequency. This only works on certain platforms.
+		 */
+		np1 = of_find_node_by_name(NULL, "cpu");
+		if (!np1) {
+			netdev_warn(lp->ndev, "Could not find CPU device node.\n");
+			host_clock = DEFAULT_HOST_CLOCK;
+		} else {
+			ret = of_property_read_u32(np1, "clock-frequency",
+						   &host_clock);
+			if (ret) {
+				netdev_warn(lp->ndev, "CPU clock-frequency property not found.\n");
+				host_clock = DEFAULT_HOST_CLOCK;
+			}
+			of_node_put(np1);
+		}
+		netdev_info(lp->ndev, "Setting assumed host clock to %u\n",
+			    host_clock);
+	}
 
 	/* clk_div can be calculated by deriving it from the equation:
 	 * fMDIO = fHOST / ((1 + clk_div) * 2)
@@ -155,25 +179,6 @@ int axienet_mdio_setup(struct axienet_local *lp, struct device_node *np)
 	 * "clock-frequency" from the CPU
 	 */
 
-	np1 = of_find_node_by_name(NULL, "cpu");
-	if (!np1) {
-		netdev_warn(lp->ndev, "Could not find CPU device node.\n");
-		netdev_warn(lp->ndev,
-			    "Setting MDIO clock divisor to default %d\n",
-			    DEFAULT_CLOCK_DIVISOR);
-		clk_div = DEFAULT_CLOCK_DIVISOR;
-		goto issue;
-	}
-	if (of_property_read_u32(np1, "clock-frequency", &host_clock)) {
-		netdev_warn(lp->ndev, "clock-frequency property not found.\n");
-		netdev_warn(lp->ndev,
-			    "Setting MDIO clock divisor to default %d\n",
-			    DEFAULT_CLOCK_DIVISOR);
-		clk_div = DEFAULT_CLOCK_DIVISOR;
-		of_node_put(np1);
-		goto issue;
-	}
-
 	clk_div = (host_clock / (MAX_MDIO_FREQ * 2)) - 1;
 	/* If there is any remainder from the division of
 	 * fHOST / (MAX_MDIO_FREQ * 2), then we need to add
@@ -186,8 +191,6 @@ int axienet_mdio_setup(struct axienet_local *lp, struct device_node *np)
 		   "Setting MDIO clock divisor to %u/%u Hz host clock.\n",
 		   clk_div, host_clock);
 
-	of_node_put(np1);
-issue:
 	axienet_iow(lp, XAE_MDIO_MC_OFFSET,
 		    (((u32) clk_div) | XAE_MDIO_MC_MDIOEN_MASK));