net: add support for STMicroelectronics Ethernet controllers.

This is the driver for the ST MAC 10/100/1000 on-chip Ethernet
controllers (Synopsys IP blocks).

Driver documentation:
 o http://stlinux.com/drupal/kernel/network/stmmac
Revisions:
 o http://stlinux.com/drupal/kernel/network/stmmac-driver-revisions
Performances:
 o http://stlinux.com/drupal/benchmarks/networking/stmmac

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/stmmac/stmmac_mdio.c b/drivers/net/stmmac/stmmac_mdio.c
new file mode 100644
index 0000000..8498552
--- /dev/null
+++ b/drivers/net/stmmac/stmmac_mdio.c
@@ -0,0 +1,217 @@
+/*******************************************************************************
+  STMMAC Ethernet Driver -- MDIO bus implementation
+  Provides Bus interface for MII registers
+
+  Copyright (C) 2007-2009  STMicroelectronics Ltd
+
+  This program is free software; you can redistribute it and/or modify it
+  under the terms and conditions of the GNU General Public License,
+  version 2, as published by the Free Software Foundation.
+
+  This program is distributed in the hope it will be useful, but WITHOUT
+  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+  more details.
+
+  You should have received a copy of the GNU General Public License along with
+  this program; if not, write to the Free Software Foundation, Inc.,
+  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+
+  The full GNU General Public License is included in this distribution in
+  the file called "COPYING".
+
+  Author: Carl Shaw <carl.shaw@st.com>
+  Maintainer: Giuseppe Cavallaro <peppe.cavallaro@st.com>
+*******************************************************************************/
+
+#include <linux/netdevice.h>
+#include <linux/mii.h>
+#include <linux/phy.h>
+
+#include "stmmac.h"
+
+#define MII_BUSY 0x00000001
+#define MII_WRITE 0x00000002
+
+/**
+ * stmmac_mdio_read
+ * @bus: points to the mii_bus structure
+ * @phyaddr: MII addr reg bits 15-11
+ * @phyreg: MII addr reg bits 10-6
+ * Description: it reads data from the MII register from within the phy device.
+ * For the 7111 GMAC, we must set the bit 0 in the MII address register while
+ * accessing the PHY registers.
+ * Fortunately, it seems this has no drawback for the 7109 MAC.
+ */
+static int stmmac_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg)
+{
+	struct net_device *ndev = bus->priv;
+	struct stmmac_priv *priv = netdev_priv(ndev);
+	unsigned long ioaddr = ndev->base_addr;
+	unsigned int mii_address = priv->mac_type->hw.mii.addr;
+	unsigned int mii_data = priv->mac_type->hw.mii.data;
+
+	int data;
+	u16 regValue = (((phyaddr << 11) & (0x0000F800)) |
+			((phyreg << 6) & (0x000007C0)));
+	regValue |= MII_BUSY;	/* in case of GMAC */
+
+	do {} while (((readl(ioaddr + mii_address)) & MII_BUSY) == 1);
+	writel(regValue, ioaddr + mii_address);
+	do {} while (((readl(ioaddr + mii_address)) & MII_BUSY) == 1);
+
+	/* Read the data from the MII data register */
+	data = (int)readl(ioaddr + mii_data);
+
+	return data;
+}
+
+/**
+ * stmmac_mdio_write
+ * @bus: points to the mii_bus structure
+ * @phyaddr: MII addr reg bits 15-11
+ * @phyreg: MII addr reg bits 10-6
+ * @phydata: phy data
+ * Description: it writes the data into the MII register from within the device.
+ */
+static int stmmac_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg,
+			     u16 phydata)
+{
+	struct net_device *ndev = bus->priv;
+	struct stmmac_priv *priv = netdev_priv(ndev);
+	unsigned long ioaddr = ndev->base_addr;
+	unsigned int mii_address = priv->mac_type->hw.mii.addr;
+	unsigned int mii_data = priv->mac_type->hw.mii.data;
+
+	u16 value =
+	    (((phyaddr << 11) & (0x0000F800)) | ((phyreg << 6) & (0x000007C0)))
+	    | MII_WRITE;
+
+	value |= MII_BUSY;
+
+	/* Wait until any existing MII operation is complete */
+	do {} while (((readl(ioaddr + mii_address)) & MII_BUSY) == 1);
+
+	/* Set the MII address register to write */
+	writel(phydata, ioaddr + mii_data);
+	writel(value, ioaddr + mii_address);
+
+	/* Wait until any existing MII operation is complete */
+	do {} while (((readl(ioaddr + mii_address)) & MII_BUSY) == 1);
+
+	return 0;
+}
+
+/**
+ * stmmac_mdio_reset
+ * @bus: points to the mii_bus structure
+ * Description: reset the MII bus
+ */
+static int stmmac_mdio_reset(struct mii_bus *bus)
+{
+	struct net_device *ndev = bus->priv;
+	struct stmmac_priv *priv = netdev_priv(ndev);
+	unsigned long ioaddr = ndev->base_addr;
+	unsigned int mii_address = priv->mac_type->hw.mii.addr;
+
+	if (priv->phy_reset) {
+		pr_debug("stmmac_mdio_reset: calling phy_reset\n");
+		priv->phy_reset(priv->bsp_priv);
+	}
+
+	/* This is a workaround for problems with the STE101P PHY.
+	 * It doesn't complete its reset until at least one clock cycle
+	 * on MDC, so perform a dummy mdio read.
+	 */
+	writel(0, ioaddr + mii_address);
+
+	return 0;
+}
+
+/**
+ * stmmac_mdio_register
+ * @ndev: net device structure
+ * Description: it registers the MII bus
+ */
+int stmmac_mdio_register(struct net_device *ndev)
+{
+	int err = 0;
+	struct mii_bus *new_bus;
+	int *irqlist;
+	struct stmmac_priv *priv = netdev_priv(ndev);
+	int addr, found;
+
+	new_bus = mdiobus_alloc();
+	if (new_bus == NULL)
+		return -ENOMEM;
+
+	irqlist = kzalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
+	if (irqlist == NULL) {
+		err = -ENOMEM;
+		goto irqlist_alloc_fail;
+	}
+
+	/* Assign IRQ to phy at address phy_addr */
+	if (priv->phy_addr != -1)
+		irqlist[priv->phy_addr] = priv->phy_irq;
+
+	new_bus->name = "STMMAC MII Bus";
+	new_bus->read = &stmmac_mdio_read;
+	new_bus->write = &stmmac_mdio_write;
+	new_bus->reset = &stmmac_mdio_reset;
+	snprintf(new_bus->id, MII_BUS_ID_SIZE, "%x", priv->bus_id);
+	new_bus->priv = ndev;
+	new_bus->irq = irqlist;
+	new_bus->phy_mask = priv->phy_mask;
+	new_bus->parent = priv->device;
+	err = mdiobus_register(new_bus);
+	if (err != 0) {
+		pr_err("%s: Cannot register as MDIO bus\n", new_bus->name);
+		goto bus_register_fail;
+	}
+
+	priv->mii = new_bus;
+
+	found = 0;
+	for (addr = 0; addr < 32; addr++) {
+		struct phy_device *phydev = new_bus->phy_map[addr];
+		if (phydev) {
+			if (priv->phy_addr == -1) {
+				priv->phy_addr = addr;
+				phydev->irq = priv->phy_irq;
+				irqlist[addr] = priv->phy_irq;
+			}
+			pr_info("%s: PHY ID %08x at %d IRQ %d (%s)%s\n",
+			       ndev->name, phydev->phy_id, addr,
+			       phydev->irq, dev_name(&phydev->dev),
+			       (addr == priv->phy_addr) ? " active" : "");
+			found = 1;
+		}
+	}
+
+	if (!found)
+		pr_warning("%s: No PHY found\n", ndev->name);
+
+	return 0;
+bus_register_fail:
+	kfree(irqlist);
+irqlist_alloc_fail:
+	kfree(new_bus);
+	return err;
+}
+
+/**
+ * stmmac_mdio_unregister
+ * @ndev: net device structure
+ * Description: it unregisters the MII bus
+ */
+int stmmac_mdio_unregister(struct net_device *ndev)
+{
+	struct stmmac_priv *priv = netdev_priv(ndev);
+
+	mdiobus_unregister(priv->mii);
+	priv->mii->priv = NULL;
+	kfree(priv->mii);
+
+	return 0;
+}