1 files changed, 151 insertions, 78 deletions

diff --git a/drivers/net/ethernet/marvell/mvmdio.c b/drivers/net/ethernet/marvell/mvmdio.c
index 74f1c157a48..fc2fb25343f 100644
--- a/drivers/net/ethernet/marvell/mvmdio.c
+++ b/drivers/net/ethernet/marvell/mvmdio.c
@@ -4,11 +4,9 @@
  * Since the MDIO interface of Marvell network interfaces is shared
  * between all network interfaces, having a single driver allows to
  * handle concurrent accesses properly (you may have four Ethernet
- * ports, but they in fact share the same SMI interface to access the
- * MDIO bus). Moreover, this MDIO interface code is similar between
- * the mv643xx_eth driver and the mvneta driver. For now, it is only
- * used by the mvneta driver, but it could later be used by the
- * mv643xx_eth driver as well.
+ * ports, but they in fact share the same SMI interface to access
+ * the MDIO bus). This driver is currently used by the mvneta and
+ * mv643xx_eth drivers.
  *
  * Copyright (C) 2012 Marvell
  *
@@ -19,15 +17,18 @@
  * warranty of any kind, whether express or implied.
  */
 
-#include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/phy.h>
-#include <linux/of_address.h>
-#include <linux/of_mdio.h>
+#include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/of_mdio.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
 
 #define MVMDIO_SMI_DATA_SHIFT              0
 #define MVMDIO_SMI_PHY_ADDR_SHIFT          16
@@ -36,79 +37,111 @@
 #define MVMDIO_SMI_WRITE_OPERATION         0
 #define MVMDIO_SMI_READ_VALID              BIT(27)
 #define MVMDIO_SMI_BUSY                    BIT(28)
+#define MVMDIO_ERR_INT_CAUSE		   0x007C
+#define  MVMDIO_ERR_INT_SMI_DONE	   0x00000010
+#define MVMDIO_ERR_INT_MASK		   0x0080
+
+/*
+ * SMI Timeout measurements:
+ * - Kirkwood 88F6281 (Globalscale Dreamplug): 45us to 95us (Interrupt)
+ * - Armada 370       (Globalscale Mirabox):   41us to 43us (Polled)
+ */
+#define MVMDIO_SMI_TIMEOUT		   1000 /* 1000us = 1ms */
+#define MVMDIO_SMI_POLL_INTERVAL_MIN	   45
+#define MVMDIO_SMI_POLL_INTERVAL_MAX	   55
 
 struct orion_mdio_dev {
 	struct mutex lock;
-	void __iomem *smireg;
+	void __iomem *regs;
+	struct clk *clk;
+	/*
+	 * If we have access to the error interrupt pin (which is
+	 * somewhat misnamed as it not only reflects internal errors
+	 * but also reflects SMI completion), use that to wait for
+	 * SMI access completion instead of polling the SMI busy bit.
+	 */
+	int err_interrupt;
+	wait_queue_head_t smi_busy_wait;
 };
 
+static int orion_mdio_smi_is_done(struct orion_mdio_dev *dev)
+{
+	return !(readl(dev->regs) & MVMDIO_SMI_BUSY);
+}
+
 /* Wait for the SMI unit to be ready for another operation
  */
 static int orion_mdio_wait_ready(struct mii_bus *bus)
 {
 	struct orion_mdio_dev *dev = bus->priv;
-	int count;
-	u32 val;
+	unsigned long timeout = usecs_to_jiffies(MVMDIO_SMI_TIMEOUT);
+	unsigned long end = jiffies + timeout;
+	int timedout = 0;
 
-	count = 0;
 	while (1) {
-		val = readl(dev->smireg);
-		if (!(val & MVMDIO_SMI_BUSY))
+	        if (orion_mdio_smi_is_done(dev))
+			return 0;
+	        else if (timedout)
 			break;
 
-		if (count > 100) {
-			dev_err(bus->parent, "Timeout: SMI busy for too long\n");
-			return -ETIMEDOUT;
-		}
-
-		udelay(10);
-		count++;
+	        if (dev->err_interrupt <= 0) {
+			usleep_range(MVMDIO_SMI_POLL_INTERVAL_MIN,
+				     MVMDIO_SMI_POLL_INTERVAL_MAX);
+
+			if (time_is_before_jiffies(end))
+				++timedout;
+	        } else {
+			/* wait_event_timeout does not guarantee a delay of at
+			 * least one whole jiffie, so timeout must be no less
+			 * than two.
+			 */
+			if (timeout < 2)
+				timeout = 2;
+			wait_event_timeout(dev->smi_busy_wait,
+				           orion_mdio_smi_is_done(dev),
+				           timeout);
+
+			++timedout;
+	        }
 	}
 
-	return 0;
+	dev_err(bus->parent, "Timeout: SMI busy for too long\n");
+	return  -ETIMEDOUT;
 }
 
 static int orion_mdio_read(struct mii_bus *bus, int mii_id,
 			   int regnum)
 {
 	struct orion_mdio_dev *dev = bus->priv;
-	int count;
 	u32 val;
 	int ret;
 
 	mutex_lock(&dev->lock);
 
 	ret = orion_mdio_wait_ready(bus);
-	if (ret < 0) {
-		mutex_unlock(&dev->lock);
-		return ret;
-	}
+	if (ret < 0)
+		goto out;
 
 	writel(((mii_id << MVMDIO_SMI_PHY_ADDR_SHIFT) |
 		(regnum << MVMDIO_SMI_PHY_REG_SHIFT)  |
 		MVMDIO_SMI_READ_OPERATION),
-	       dev->smireg);
-
-	/* Wait for the value to become available */
-	count = 0;
-	while (1) {
-		val = readl(dev->smireg);
-		if (val & MVMDIO_SMI_READ_VALID)
-			break;
+	       dev->regs);
 
-		if (count > 100) {
-			dev_err(bus->parent, "Timeout when reading PHY\n");
-			mutex_unlock(&dev->lock);
-			return -ETIMEDOUT;
-		}
-
-		udelay(10);
-		count++;
+	ret = orion_mdio_wait_ready(bus);
+	if (ret < 0)
+		goto out;
+
+	val = readl(dev->regs);
+	if (!(val & MVMDIO_SMI_READ_VALID)) {
+		dev_err(bus->parent, "SMI bus read not valid\n");
+		ret = -ENODEV;
+		goto out;
 	}
 
+	ret = val & 0xFFFF;
+out:
 	mutex_unlock(&dev->lock);
-
-	return val & 0xFFFF;
+	return ret;
 }
 
 static int orion_mdio_write(struct mii_bus *bus, int mii_id,
@@ -120,89 +153,128 @@ static int orion_mdio_write(struct mii_bus *bus, int mii_id,
 	mutex_lock(&dev->lock);
 
 	ret = orion_mdio_wait_ready(bus);
-	if (ret < 0) {
-		mutex_unlock(&dev->lock);
-		return ret;
-	}
+	if (ret < 0)
+		goto out;
 
 	writel(((mii_id << MVMDIO_SMI_PHY_ADDR_SHIFT) |
 		(regnum << MVMDIO_SMI_PHY_REG_SHIFT)  |
 		MVMDIO_SMI_WRITE_OPERATION            |
 		(value << MVMDIO_SMI_DATA_SHIFT)),
-	       dev->smireg);
+	       dev->regs);
 
+out:
 	mutex_unlock(&dev->lock);
-
-	return 0;
+	return ret;
 }
 
-static int orion_mdio_reset(struct mii_bus *bus)
+static irqreturn_t orion_mdio_err_irq(int irq, void *dev_id)
 {
-	return 0;
+	struct orion_mdio_dev *dev = dev_id;
+
+	if (readl(dev->regs + MVMDIO_ERR_INT_CAUSE) &
+			MVMDIO_ERR_INT_SMI_DONE) {
+		writel(~MVMDIO_ERR_INT_SMI_DONE,
+				dev->regs + MVMDIO_ERR_INT_CAUSE);
+		wake_up(&dev->smi_busy_wait);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
 }
 
 static int orion_mdio_probe(struct platform_device *pdev)
 {
-	struct device_node *np = pdev->dev.of_node;
+	struct resource *r;
 	struct mii_bus *bus;
 	struct orion_mdio_dev *dev;
 	int i, ret;
 
-	bus = mdiobus_alloc_size(sizeof(struct orion_mdio_dev));
-	if (!bus) {
-		dev_err(&pdev->dev, "Cannot allocate MDIO bus\n");
-		return -ENOMEM;
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		dev_err(&pdev->dev, "No SMI register address given\n");
+		return -ENODEV;
 	}
 
+	bus = devm_mdiobus_alloc_size(&pdev->dev,
+				      sizeof(struct orion_mdio_dev));
+	if (!bus)
+		return -ENOMEM;
+
 	bus->name = "orion_mdio_bus";
 	bus->read = orion_mdio_read;
 	bus->write = orion_mdio_write;
-	bus->reset = orion_mdio_reset;
 	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii",
 		 dev_name(&pdev->dev));
 	bus->parent = &pdev->dev;
 
-	bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
-	if (!bus->irq) {
-		dev_err(&pdev->dev, "Cannot allocate PHY IRQ array\n");
-		mdiobus_free(bus);
+	bus->irq = devm_kmalloc_array(&pdev->dev, PHY_MAX_ADDR, sizeof(int),
+				      GFP_KERNEL);
+	if (!bus->irq)
 		return -ENOMEM;
-	}
 
 	for (i = 0; i < PHY_MAX_ADDR; i++)
 		bus->irq[i] = PHY_POLL;
 
 	dev = bus->priv;
-	dev->smireg = of_iomap(pdev->dev.of_node, 0);
-	if (!dev->smireg) {
-		dev_err(&pdev->dev, "No SMI register address given in DT\n");
-		kfree(bus->irq);
-		mdiobus_free(bus);
-		return -ENODEV;
+	dev->regs = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+	if (!dev->regs) {
+		dev_err(&pdev->dev, "Unable to remap SMI register\n");
+		ret = -ENODEV;
+		goto out_mdio;
+	}
+
+	init_waitqueue_head(&dev->smi_busy_wait);
+
+	dev->clk = devm_clk_get(&pdev->dev, NULL);
+	if (!IS_ERR(dev->clk))
+		clk_prepare_enable(dev->clk);
+
+	dev->err_interrupt = platform_get_irq(pdev, 0);
+	if (dev->err_interrupt > 0) {
+		ret = devm_request_irq(&pdev->dev, dev->err_interrupt,
+					orion_mdio_err_irq,
+					IRQF_SHARED, pdev->name, dev);
+		if (ret)
+			goto out_mdio;
+
+		writel(MVMDIO_ERR_INT_SMI_DONE,
+			dev->regs + MVMDIO_ERR_INT_MASK);
+
+	} else if (dev->err_interrupt == -EPROBE_DEFER) {
+		return -EPROBE_DEFER;
 	}
 
 	mutex_init(&dev->lock);
 
-	ret = of_mdiobus_register(bus, np);
+	if (pdev->dev.of_node)
+		ret = of_mdiobus_register(bus, pdev->dev.of_node);
+	else
+		ret = mdiobus_register(bus);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Cannot register MDIO bus (%d)\n", ret);
-		iounmap(dev->smireg);
-		kfree(bus->irq);
-		mdiobus_free(bus);
-		return ret;
+		goto out_mdio;
 	}
 
 	platform_set_drvdata(pdev, bus);
 
 	return 0;
+
+out_mdio:
+	if (!IS_ERR(dev->clk))
+		clk_disable_unprepare(dev->clk);
+	return ret;
 }
 
 static int orion_mdio_remove(struct platform_device *pdev)
 {
 	struct mii_bus *bus = platform_get_drvdata(pdev);
+	struct orion_mdio_dev *dev = bus->priv;
+
+	writel(0, dev->regs + MVMDIO_ERR_INT_MASK);
 	mdiobus_unregister(bus);
-	kfree(bus->irq);
-	mdiobus_free(bus);
+	if (!IS_ERR(dev->clk))
+		clk_disable_unprepare(dev->clk);
+
 	return 0;
 }
 
@@ -226,3 +298,4 @@ module_platform_driver(orion_mdio_driver);
 MODULE_DESCRIPTION("Marvell MDIO interface driver");
 MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@free-electrons.com>");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:orion-mdio");