1 files changed, 70 insertions, 41 deletions

diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c b/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c
index 704babdbc8a2..435ed308d990 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c
@@ -5,9 +5,11 @@
  * Copyright (c) 2009 Secret Lab Technologies, Ltd.
  * Copyright (c) 2010 - 2011 Michal Simek <monstr@monstr.eu>
  * Copyright (c) 2010 - 2011 PetaLogix
+ * Copyright (c) 2019 SED Systems, a division of Calian Ltd.
  * 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>
@@ -16,10 +18,10 @@
 #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)
+static int axienet_mdio_wait_until_ready(struct axienet_local *lp)
 {
 	u32 val;
 
@@ -112,23 +114,42 @@ static int axienet_mdio_write(struct mii_bus *bus, int phy_id, int reg,
 }
 
 /**
- * axienet_mdio_setup - MDIO setup function
+ * axienet_mdio_enable - MDIO hardware 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.
+ * Return:	0 on success, -ETIMEDOUT on a timeout.
  *
  * Sets up the MDIO interface by initializing the MDIO clock and enabling the
- * MDIO interface in hardware. Register the MDIO interface.
+ * MDIO interface in hardware.
  **/
-int axienet_mdio_setup(struct axienet_local *lp, struct device_node *np)
+int axienet_mdio_enable(struct axienet_local *lp)
 {
-	int ret;
 	u32 clk_div, host_clock;
-	struct mii_bus *bus;
-	struct resource res;
-	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 {
+			int 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 +176,6 @@ 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
@@ -186,12 +188,39 @@ 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));
+	axienet_iow(lp, XAE_MDIO_MC_OFFSET, clk_div | XAE_MDIO_MC_MDIOEN_MASK);
 
-	ret = axienet_mdio_wait_until_ready(lp);
+	return axienet_mdio_wait_until_ready(lp);
+}
+
+/**
+ * axienet_mdio_disable - MDIO hardware disable function
+ * @lp:		Pointer to axienet local data structure.
+ *
+ * Disable the MDIO interface in hardware.
+ **/
+void axienet_mdio_disable(struct axienet_local *lp)
+{
+	axienet_iow(lp, XAE_MDIO_MC_OFFSET, 0);
+}
+
+/**
+ * axienet_mdio_setup - MDIO setup function
+ * @lp:		Pointer to axienet local data structure.
+ *
+ * Return:	0 on success, -ETIMEDOUT on a timeout, -ENOMEM when
+ *		mdiobus_alloc (to allocate memory for mii bus structure) fails.
+ *
+ * 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 *mdio_node;
+	struct mii_bus *bus;
+	int ret;
+
+	ret = axienet_mdio_enable(lp);
 	if (ret < 0)
 		return ret;
 
@@ -199,10 +228,8 @@ issue:
 	if (!bus)
 		return -ENOMEM;
 
-	np1 = of_get_parent(lp->phy_node);
-	of_address_to_resource(np1, 0, &res);
-	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
-		 (unsigned long long) res.start);
+	snprintf(bus->id, MII_BUS_ID_SIZE, "axienet-%.8llx",
+		 (unsigned long long)lp->regs_start);
 
 	bus->priv = lp;
 	bus->name = "Xilinx Axi Ethernet MDIO";
@@ -211,7 +238,9 @@ issue:
 	bus->parent = lp->dev;
 	lp->mii_bus = bus;
 
-	ret = of_mdiobus_register(bus, np1);
+	mdio_node = of_get_child_by_name(lp->dev->of_node, "mdio");
+	ret = of_mdiobus_register(bus, mdio_node);
+	of_node_put(mdio_node);
 	if (ret) {
 		mdiobus_free(bus);
 		lp->mii_bus = NULL;