Patchwork [V2] net: emaclite: adding MDIO and phy lib support

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Submitter John Linn
Date Feb. 5, 2010, 10:40 p.m.
Message ID <3d0d49ee-ead6-4286-8486-193f1f10345f@VA3EHSMHS024.ehs.local>
Download mbox | patch
Permalink /patch/44681/
State Not Applicable
Headers show

Comments

John Linn - Feb. 5, 2010, 10:40 p.m.
These changes add MDIO and phy lib support to the driver as the
IP core now supports the MDIO bus.

The MDIO bus and phy are added as a child to the emaclite in the device
tree as illustrated below.

mdio {
	#address-cells = <1>;
	#size-cells = <0>;
	compatible = "xlnx,emaclite-mdio";
	phy0: phy@7 {
		reg = <7>;
	} ;
}

Signed-off-by: Sadanand Mutyala <Sadanand.Mutyala@xilinx.com>
Signed-off-by: John Linn <john.linn@xilinx.com>

---

V2 - updated it for Grant's comments, except I couldn't find any tabs
converted to white space issue, let's see if V2 has it also
---
 drivers/net/Kconfig           |    1 +
 drivers/net/xilinx_emaclite.c |  393 ++++++++++++++++++++++++++++++++++++-----
 2 files changed, 351 insertions(+), 43 deletions(-)

Patch

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index dd9a09c..9509a36 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -1939,6 +1939,7 @@  config ATL2
 config XILINX_EMACLITE
 	tristate "Xilinx 10/100 Ethernet Lite support"
 	depends on PPC32 || MICROBLAZE
+	select PHYLIB
 	help
 	  This driver supports the 10/100 Ethernet Lite from Xilinx.
 
diff --git a/drivers/net/xilinx_emaclite.c b/drivers/net/xilinx_emaclite.c
index 8c777ba..02f18dd 100644
--- a/drivers/net/xilinx_emaclite.c
+++ b/drivers/net/xilinx_emaclite.c
@@ -22,11 +22,17 @@ 
 
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
 
 #define DRIVER_NAME "xilinx_emaclite"
 
 /* Register offsets for the EmacLite Core */
 #define XEL_TXBUFF_OFFSET 	0x0		/* Transmit Buffer */
+#define XEL_MDIOADDR_OFFSET	0x07E4		/* MDIO Address Register */
+#define XEL_MDIOWR_OFFSET	0x07E8		/* MDIO Write Data Register */
+#define XEL_MDIORD_OFFSET	0x07EC		/* MDIO Read Data Register */
+#define XEL_MDIOCTRL_OFFSET	0x07F0		/* MDIO Control Register */
 #define XEL_GIER_OFFSET		0x07F8		/* GIE Register */
 #define XEL_TSR_OFFSET		0x07FC		/* Tx status */
 #define XEL_TPLR_OFFSET		0x07F4		/* Tx packet length */
@@ -37,6 +43,22 @@ 
 
 #define XEL_BUFFER_OFFSET	0x0800		/* Next Tx/Rx buffer's offset */
 
+/* MDIO Address Register Bit Masks */
+#define XEL_MDIOADDR_REGADR_MASK  0x0000001F	/* Register Address */
+#define XEL_MDIOADDR_PHYADR_MASK  0x000003E0	/* PHY Address */
+#define XEL_MDIOADDR_PHYADR_SHIFT 5
+#define XEL_MDIOADDR_OP_MASK	  0x00000400	/* RD/WR Operation */
+
+/* MDIO Write Data Register Bit Masks */
+#define XEL_MDIOWR_WRDATA_MASK	  0x0000FFFF	/* Data to be Written */
+
+/* MDIO Read Data Register Bit Masks */
+#define XEL_MDIORD_RDDATA_MASK	  0x0000FFFF	/* Data to be Read */
+
+/* MDIO Control Register Bit Masks */
+#define XEL_MDIOCTRL_MDIOSTS_MASK 0x00000001	/* MDIO Status Mask */
+#define XEL_MDIOCTRL_MDIOEN_MASK  0x00000008	/* MDIO Enable */
+
 /* Global Interrupt Enable Register (GIER) Bit Masks */
 #define XEL_GIER_GIE_MASK	0x80000000 	/* Global Enable */
 
@@ -87,6 +109,13 @@ 
  * @reset_lock:		lock used for synchronization
  * @deferred_skb:	holds an skb (for transmission at a later time) when the
  *			Tx buffer is not free
+ * @phy_dev:		pointer to the PHY device
+ * @phy_node:		pointer to the PHY device node
+ * @mii_bus:		pointer to the MII bus
+ * @mdio_irqs:		IRQs table for MDIO bus
+ * @last_link:		last link status
+ * @has_mdio:		indicates whether MDIO is included in the HW
+ * @mdio_mutex:		protects MDIO accesses
  */
 struct net_local {
 
@@ -100,6 +129,16 @@  struct net_local {
 
 	spinlock_t reset_lock;
 	struct sk_buff *deferred_skb;
+
+	struct phy_device *phy_dev;
+	struct device_node *phy_node;
+
+	struct mii_bus *mii_bus;
+	int mdio_irqs[PHY_MAX_ADDR];
+
+	int last_link;
+	bool has_mdio;
+	struct mutex mdio_mutex;
 };
 
 
@@ -431,7 +470,7 @@  static u16 xemaclite_recv_data(struct net_local *drvdata, u8 *data)
 }
 
 /**
- * xemaclite_set_mac_address - Set the MAC address for this device
+ * xemaclite_update_address - Update the MAC address in the device
  * @drvdata:	Pointer to the Emaclite device private data
  * @address_ptr:Pointer to the MAC address (MAC address is a 48-bit value)
  *
@@ -441,8 +480,8 @@  static u16 xemaclite_recv_data(struct net_local *drvdata, u8 *data)
  * The MAC address can be programmed using any of the two transmit
  * buffers (if configured).
  */
-static void xemaclite_set_mac_address(struct net_local *drvdata,
-				      u8 *address_ptr)
+static void xemaclite_update_address(struct net_local *drvdata,
+				     u8 *address_ptr)
 {
 	void __iomem *addr;
 	u32 reg_data;
@@ -465,6 +504,30 @@  static void xemaclite_set_mac_address(struct net_local *drvdata,
 }
 
 /**
+ * xemaclite_set_mac_address - Set the MAC address for this device
+ * @dev:	Pointer to the network device instance
+ * @addr:	Void pointer to the sockaddr structure
+ *
+ * This function copies the HW address from the sockaddr strucutre to the
+ * net_device structure and updates the address in HW.
+ *
+ * Return:	Error if the net device is busy or 0 if the addr is set
+ *		successfully
+ */
+static int xemaclite_set_mac_address(struct net_device *dev, void *address)
+{
+	struct net_local *lp = (struct net_local *) netdev_priv(dev);
+	struct sockaddr *addr = address;
+
+	if (netif_running(dev))
+		return -EBUSY;
+
+	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
+	xemaclite_update_address(lp, dev->dev_addr);
+	return 0;
+}
+
+/**
  * xemaclite_tx_timeout - Callback for Tx Timeout
  * @dev:	Pointer to the network device
  *
@@ -641,12 +704,228 @@  static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+/**********************/
+/* MDIO Bus functions */
+/**********************/
+
+/**
+ * xemaclite_mdio_wait - Wait for the MDIO to be ready to use
+ * @lp:		Pointer to the Emaclite device private data
+ *
+ * This function waits till the device is ready to accept a new MDIO
+ * request. Since this function uses msleep, the mdio_mutex is used
+ * to protect MDIO processsing.
+ *
+ * Return:	0 for success or ETIMEDOUT for a timeout
+ */
+
+static int xemaclite_mdio_wait(struct net_local *lp)
+{
+	long end = jiffies + 2;
+
+	/* wait for the MDIO interface to not be busy or timeout
+	   after some time.
+	*/
+	while (in_be32(lp->base_addr + XEL_MDIOCTRL_OFFSET) &
+			XEL_MDIOCTRL_MDIOSTS_MASK) {
+		if (end - jiffies <= 0) {
+			WARN_ON(1);
+			return -ETIMEDOUT;
+		}
+		msleep(1);
+	}
+	return 0;
+}
+
+/**
+ * xemaclite_mdio_read - Read from a given MII management register
+ * @bus:	the mii_bus struct
+ * @phy_id:	the phy address
+ * @reg:	register number to read from
+ *
+ * This function waits till the device is ready to accept a new MDIO
+ * request and then writes the phy address to the MDIO Address register
+ * and reads data from MDIO Read Data register, when its available.
+ *
+ * Return:	Value read from the MII management register
+ */
+static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
+{
+	struct net_local *lp = bus->priv;
+	u32 ctrl_reg;
+	u32 rc;
+
+	mutex_lock(&lp->mdio_mutex);
+
+	if (xemaclite_mdio_wait(lp))
+		return -ETIMEDOUT;
+
+	/* Write the PHY address, register number and set the OP bit in the
+	 * MDIO Address register. Set the Status bit in the MDIO Control
+	 * register to start a MDIO read transaction.
+	 */
+	ctrl_reg = in_be32(lp->base_addr + XEL_MDIOCTRL_OFFSET);
+	out_be32(lp->base_addr + XEL_MDIOADDR_OFFSET,
+		 XEL_MDIOADDR_OP_MASK |
+		 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg));
+	out_be32(lp->base_addr + XEL_MDIOCTRL_OFFSET,
+		 ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK);
+
+	if (xemaclite_mdio_wait(lp))
+		return -ETIMEDOUT;
+
+	rc = in_be32(lp->base_addr + XEL_MDIORD_OFFSET);
+
+	mutex_unlock(&lp->mdio_mutex);
+
+	dev_dbg(&lp->ndev->dev,
+		"xemaclite_mdio_read(phy_id=%i, reg=%x) == %x\n",
+		phy_id, reg, rc);
+
+	return rc;
+}
+
+/**
+ * xemaclite_mdio_write - Write to a given MII management register
+ * @bus:	the mii_bus struct
+ * @phy_id:	the phy address
+ * @reg:	register number to write to
+ * @val:	value to write to the register number specified by reg
+ *
+ * This fucntion waits till the device is ready to accept a new MDIO
+ * request and then writes the val to the MDIO Write Data register.
+ */
+static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
+				u16 val)
+{
+	struct net_local *lp = bus->priv;
+	u32 ctrl_reg;
+
+	dev_dbg(&lp->ndev->dev,
+		"xemaclite_mdio_write(phy_id=%i, reg=%x, val=%x)\n",
+		phy_id, reg, val);
+
+	mutex_lock(&lp->mdio_mutex);
+
+	if (xemaclite_mdio_wait(lp))
+		return -ETIMEDOUT;
+
+	/* Write the PHY address, register number and clear the OP bit in the
+	 * MDIO Address register and then write the value into the MDIO Write
+	 * Data register. Finally, set the Status bit in the MDIO Control
+	 * register to start a MDIO write transaction.
+	 */
+	ctrl_reg = in_be32(lp->base_addr + XEL_MDIOCTRL_OFFSET);
+	out_be32(lp->base_addr + XEL_MDIOADDR_OFFSET,
+		 ~XEL_MDIOADDR_OP_MASK &
+		 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg));
+	out_be32(lp->base_addr + XEL_MDIOWR_OFFSET, val);
+	out_be32(lp->base_addr + XEL_MDIOCTRL_OFFSET,
+		 ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK);
+
+	mutex_unlock(&lp->mdio_mutex);
+
+	return 0;
+}
+
+/**
+ * xemaclite_mdio_reset - Reset the mdio bus.
+ * @bus:	Pointer to the MII bus
+ *
+ * This function is required(?) as per Documentation/networking/phy.txt.
+ * There is no reset in this device; this function always returns 0.
+ */
+static int xemaclite_mdio_reset(struct mii_bus *bus)
+{
+	return 0;
+}
+
+/**
+ * xemaclite_mdio_setup - Register mii_bus for the Emaclite device
+ * @lp:		Pointer to the Emaclite device private data
+ * @ofdev:	Pointer to OF device structure
+ *
+ * This function enables MDIO bus in the Emaclite device and registers a
+ * mii_bus.
+ *
+ * Return:	0 upon success or a negative error upon failure
+ */
+static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
+{
+	struct mii_bus *bus;
+	int rc;
+	struct resource res;
+	struct device_node *np = of_get_parent(lp->phy_node);
+
+	/* Don't register the MDIO bus if the phy_node or its parent node
+	 * can't be found.
+	 */
+	if (!np)
+		return -ENODEV;
+
+	/* Enable the MDIO bus by asserting the enable bit in MDIO Control
+	 * register.
+	 */
+	out_be32(lp->base_addr + XEL_MDIOCTRL_OFFSET,
+		 XEL_MDIOCTRL_MDIOEN_MASK);
+
+	bus = mdiobus_alloc();
+	if (!bus)
+		return -ENOMEM;
+
+	of_address_to_resource(np, 0, &res);
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
+		 (unsigned long long)res.start);
+	bus->priv = lp;
+	bus->name = "Xilinx Emaclite MDIO";
+	bus->read = xemaclite_mdio_read;
+	bus->write = xemaclite_mdio_write;
+	bus->reset = xemaclite_mdio_reset;
+	bus->parent = dev;
+	bus->irq = lp->mdio_irqs; /* preallocated IRQ table */
+
+	lp->mii_bus = bus;
+
+	rc = of_mdiobus_register(bus, np);
+	if (rc)
+		goto err_register;
+
+	return 0;
+
+err_register:
+	mdiobus_free(bus);
+	return rc;
+}
+
+/**
+ * xemaclite_adjust_link - Link state callback for the Emaclite device
+ * @ndev: pointer to net_device struct
+ *
+ * There's nothing in the Emaclite device to be configured when the link
+ * state changes. We just print the status.
+ */
+void xemaclite_adjust_link(struct net_device *ndev)
+{
+	struct net_local *lp = netdev_priv(ndev);
+	struct phy_device *phy = lp->phy_dev;
+	int link_state;
+
+	/* hash together the state values to decide if something has changed */
+	link_state = phy->speed | (phy->duplex << 1) | phy->link;
+
+	if (lp->last_link != link_state) {
+		lp->last_link = link_state;
+		phy_print_status(phy);
+	}
+}
+
 /**
  * xemaclite_open - Open the network device
  * @dev:	Pointer to the network device
  *
  * This function sets the MAC address, requests an IRQ and enables interrupts
  * for the Emaclite device and starts the Tx queue.
+ * It also connects to the phy device, if MDIO is included in Emaclite device.
  */
 static int xemaclite_open(struct net_device *dev)
 {
@@ -656,14 +935,50 @@  static int xemaclite_open(struct net_device *dev)
 	/* Just to be safe, stop the device first */
 	xemaclite_disable_interrupts(lp);
 
+	if (lp->phy_node) {
+		u32 bmcr;
+
+		lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
+					     xemaclite_adjust_link, 0,
+					     PHY_INTERFACE_MODE_MII);
+		if (!lp->phy_dev) {
+			dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
+			return -ENODEV;
+		}
+
+		/* EmacLite doesn't support giga-bit speeds */
+		lp->phy_dev->supported &= (PHY_BASIC_FEATURES);
+		lp->phy_dev->advertising = lp->phy_dev->supported;
+
+		/* Don't advertise 1000BASE-T Full/Half duplex speeds */
+		xemaclite_mdio_write(lp->mii_bus, lp->phy_dev->addr,
+				     MII_CTRL1000, 0x00);
+		/* Advertise only 10 and 100mbps full/half duplex speeds */
+		xemaclite_mdio_write(lp->mii_bus, lp->phy_dev->addr,
+				     MII_ADVERTISE, ADVERTISE_ALL);
+
+		/* Restart auto negotiation */
+		bmcr = xemaclite_mdio_read(lp->mii_bus,
+					   lp->phy_dev->addr, MII_BMCR);
+		bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
+		xemaclite_mdio_write(lp->mii_bus, lp->phy_dev->addr,
+				     MII_BMCR, bmcr);
+
+		phy_start(lp->phy_dev);
+	}
+
 	/* Set the MAC address each time opened */
-	xemaclite_set_mac_address(lp, dev->dev_addr);
+	xemaclite_update_address(lp, dev->dev_addr);
 
 	/* Grab the IRQ */
 	retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
 	if (retval) {
 		dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
 			dev->irq);
+		if (lp->phy_dev)
+			phy_disconnect(lp->phy_dev);
+		lp->phy_dev = NULL;
+
 		return retval;
 	}
 
@@ -682,6 +997,7 @@  static int xemaclite_open(struct net_device *dev)
  *
  * This function stops the Tx queue, disables interrupts and frees the IRQ for
  * the Emaclite device.
+ * It also disconnects the phy device associated with the Emaclite device.
  */
 static int xemaclite_close(struct net_device *dev)
 {
@@ -691,6 +1007,10 @@  static int xemaclite_close(struct net_device *dev)
 	xemaclite_disable_interrupts(lp);
 	free_irq(dev->irq, dev);
 
+	if (lp->phy_dev)
+		phy_disconnect(lp->phy_dev);
+	lp->phy_dev = NULL;
+
 	return 0;
 }
 
@@ -754,42 +1074,6 @@  static int xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
 }
 
 /**
- * xemaclite_ioctl - Perform IO Control operations on the network device
- * @dev:	Pointer to the network device
- * @rq:		Pointer to the interface request structure
- * @cmd:	IOCTL command
- *
- * The only IOCTL operation supported by this function is setting the MAC
- * address. An error is reported if any other operations are requested.
- *
- * Return:	0 to indicate success, or a negative error for failure.
- */
-static int xemaclite_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
-{
-	struct net_local *lp = (struct net_local *) netdev_priv(dev);
-	struct hw_addr_data *hw_addr = (struct hw_addr_data *) &rq->ifr_hwaddr;
-
-	switch (cmd) {
-	case SIOCETHTOOL:
-		return -EIO;
-
-	case SIOCSIFHWADDR:
-		dev_err(&lp->ndev->dev, "SIOCSIFHWADDR\n");
-
-		/* Copy MAC address in from user space */
-		copy_from_user((void __force *) dev->dev_addr,
-			       (void __user __force *) hw_addr,
-			       IFHWADDRLEN);
-		xemaclite_set_mac_address(lp, dev->dev_addr);
-		break;
-	default:
-		return -EOPNOTSUPP;
-	}
-
-	return 0;
-}
-
-/**
  * xemaclite_remove_ndev - Free the network device
  * @ndev:	Pointer to the network device to be freed
  *
@@ -840,6 +1124,8 @@  static struct net_device_ops xemaclite_netdev_ops;
  * This function probes for the Emaclite device in the device tree.
  * It initializes the driver data structure and the hardware, sets the MAC
  * address and registers the network device.
+ * It also registers a mii_bus for the Emaclite device, if MDIO is included
+ * in the device.
  *
  * Return:	0, if the driver is bound to the Emaclite device, or
  *		a negative error if there is failure.
@@ -880,6 +1166,7 @@  static int __devinit xemaclite_of_probe(struct of_device *ofdev,
 	}
 
 	dev_set_drvdata(dev, ndev);
+	SET_NETDEV_DEV(ndev, &ofdev->dev);
 
 	ndev->irq = r_irq.start;
 	ndev->mem_start = r_mem.start;
@@ -906,6 +1193,7 @@  static int __devinit xemaclite_of_probe(struct of_device *ofdev,
 	}
 
 	spin_lock_init(&lp->reset_lock);
+	mutex_init(&lp->mdio_mutex);
 	lp->next_tx_buf_to_use = 0x0;
 	lp->next_rx_buf_to_use = 0x0;
 	lp->tx_ping_pong = get_bool(ofdev, "xlnx,tx-ping-pong");
@@ -923,7 +1211,12 @@  static int __devinit xemaclite_of_probe(struct of_device *ofdev,
 	out_be32(lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET, 0);
 
 	/* Set the MAC address in the EmacLite device */
-	xemaclite_set_mac_address(lp, ndev->dev_addr);
+	xemaclite_update_address(lp, ndev->dev_addr);
+
+	lp->phy_node = of_parse_phandle(ofdev->node, "phy-handle", 0);
+	rc = xemaclite_mdio_setup(lp, &ofdev->dev);
+	if (rc)
+		dev_warn(&ofdev->dev, "error registering MDIO bus\n");
 
 	dev_info(dev,
 		 "MAC address is now %2x:%2x:%2x:%2x:%2x:%2x\n",
@@ -972,12 +1265,25 @@  static int __devexit xemaclite_of_remove(struct of_device *of_dev)
 	struct device *dev = &of_dev->dev;
 	struct net_device *ndev = dev_get_drvdata(dev);
 
+	struct net_local *lp = (struct net_local *) netdev_priv(ndev);
+
+	/* Un-register the mii_bus, if configured */
+	if (lp->has_mdio) {
+		mdiobus_unregister(lp->mii_bus);
+		kfree(lp->mii_bus->irq);
+		mdiobus_free(lp->mii_bus);
+		lp->mii_bus = NULL;
+	}
+
 	unregister_netdev(ndev);
 
+	if (lp->phy_node)
+		of_node_put(lp->phy_node);
+	lp->phy_node = NULL;
+
 	release_mem_region(ndev->mem_start, ndev->mem_end-ndev->mem_start + 1);
 
 	xemaclite_remove_ndev(ndev);
-
 	dev_set_drvdata(dev, NULL);
 
 	return 0;
@@ -987,7 +1293,7 @@  static struct net_device_ops xemaclite_netdev_ops = {
 	.ndo_open		= xemaclite_open,
 	.ndo_stop		= xemaclite_close,
 	.ndo_start_xmit		= xemaclite_send,
-	.ndo_do_ioctl		= xemaclite_ioctl,
+	.ndo_set_mac_address	= xemaclite_set_mac_address,
 	.ndo_tx_timeout		= xemaclite_tx_timeout,
 	.ndo_get_stats		= xemaclite_get_stats,
 };
@@ -999,6 +1305,7 @@  static struct of_device_id xemaclite_of_match[] __devinitdata = {
 	{ .compatible = "xlnx,xps-ethernetlite-1.00.a", },
 	{ .compatible = "xlnx,xps-ethernetlite-2.00.a", },
 	{ .compatible = "xlnx,xps-ethernetlite-2.01.a", },
+	{ .compatible = "xlnx,xps-ethernetlite-3.00.a", },
 	{ /* end of list */ },
 };
 MODULE_DEVICE_TABLE(of, xemaclite_of_match);