--- /dev/null
+/*
+ * QorIQ 10G MDIO Controller
+ *
+ * Copyright 2012 Freescale Semiconductor, Inc.
+ *
+ * Authors: Andy Fleming <afleming@freescale.com>
+ * Timur Tabi <timur@freescale.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/mdio.h>
+#include <linux/of_platform.h>
+#include <linux/of_mdio.h>
+
+/* Number of microseconds to wait for a register to respond */
+#define TIMEOUT 1000
+
+struct tgec_mdio_controller {
+ __be32 reserved[12];
+ __be32 mdio_stat; /* MDIO configuration and status */
+ __be32 mdio_ctl; /* MDIO control */
+ __be32 mdio_data; /* MDIO data */
+ __be32 mdio_addr; /* MDIO address */
+} __packed;
+
+#define MDIO_STAT_CLKDIV(x) (((x>>1) & 0xff) << 8)
+#define MDIO_STAT_BSY (1 << 0)
+#define MDIO_STAT_RD_ER (1 << 1)
+#define MDIO_CTL_DEV_ADDR(x) (x & 0x1f)
+#define MDIO_CTL_PORT_ADDR(x) ((x & 0x1f) << 5)
+#define MDIO_CTL_PRE_DIS (1 << 10)
+#define MDIO_CTL_SCAN_EN (1 << 11)
+#define MDIO_CTL_POST_INC (1 << 14)
+#define MDIO_CTL_READ (1 << 15)
+
+#define MDIO_DATA(x) (x & 0xffff)
+#define MDIO_DATA_BSY (1 << 31)
+
+/*
+ * Wait untill the MDIO bus is free
+ */
+static int xgmac_wait_until_free(struct device *dev,
+ struct tgec_mdio_controller __iomem *regs)
+{
+ uint32_t status;
+
+ /* Wait till the bus is free */
+ status = spin_event_timeout(
+ !((in_be32(®s->mdio_stat)) & MDIO_STAT_BSY), TIMEOUT, 0);
+ if (!status) {
+ dev_err(dev, "timeout waiting for bus to be free\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+/*
+ * Wait till the MDIO read or write operation is complete
+ */
+static int xgmac_wait_until_done(struct device *dev,
+ struct tgec_mdio_controller __iomem *regs)
+{
+ uint32_t status;
+
+ /* Wait till the MDIO write is complete */
+ status = spin_event_timeout(
+ !((in_be32(®s->mdio_data)) & MDIO_DATA_BSY), TIMEOUT, 0);
+ if (!status) {
+ dev_err(dev, "timeout waiting for operation to complete\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+/*
+ * Write value to the PHY for this device to the register at regnum,waiting
+ * until the write is done before it returns. All PHY configuration has to be
+ * done through the TSEC1 MIIM regs.
+ */
+static int xgmac_mdio_write(struct mii_bus *bus, int phy_id, int regnum, u16 value)
+{
+ struct tgec_mdio_controller __iomem *regs = bus->priv;
+ uint16_t dev_addr = regnum >> 16;
+ int ret;
+
+ /* Setup the MII Mgmt clock speed */
+ out_be32(®s->mdio_stat, MDIO_STAT_CLKDIV(100));
+
+ ret = xgmac_wait_until_free(&bus->dev, regs);
+ if (ret)
+ return ret;
+
+ /* Set the port and dev addr */
+ out_be32(®s->mdio_ctl,
+ MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr));
+
+ /* Set the register address */
+ out_be32(®s->mdio_addr, regnum & 0xffff);
+
+ ret = xgmac_wait_until_free(&bus->dev, regs);
+ if (ret)
+ return ret;
+
+ /* Write the value to the register */
+ out_be32(®s->mdio_data, MDIO_DATA(value));
+
+ ret = xgmac_wait_until_done(&bus->dev, regs);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+/*
+ * Reads from register regnum in the PHY for device dev, returning the value.
+ * Clears miimcom first. All PHY configuration has to be done through the
+ * TSEC1 MIIM regs.
+ */
+static int xgmac_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
+{
+ struct tgec_mdio_controller __iomem *regs = bus->priv;
+ uint16_t dev_addr = regnum >> 16;
+ uint32_t mdio_ctl;
+ uint16_t value;
+ int ret;
+
+ /* Setup the MII Mgmt clock speed */
+ out_be32(®s->mdio_stat, MDIO_STAT_CLKDIV(100));
+
+ ret = xgmac_wait_until_free(&bus->dev, regs);
+ if (ret)
+ return ret;
+
+ /* Set the Port and Device Addrs */
+ mdio_ctl = MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr);
+ out_be32(®s->mdio_ctl, mdio_ctl);
+
+ /* Set the register address */
+ out_be32(®s->mdio_addr, regnum & 0xffff);
+
+ ret = xgmac_wait_until_free(&bus->dev, regs);
+ if (ret)
+ return ret;
+
+ /* Initiate the read */
+ out_be32(®s->mdio_ctl, mdio_ctl | MDIO_CTL_READ);
+
+ ret = xgmac_wait_until_done(&bus->dev, regs);
+ if (ret)
+ return ret;
+
+ /* Return all Fs if nothing was there */
+ if (in_be32(®s->mdio_stat) & MDIO_STAT_RD_ER) {
+ dev_err(&bus->dev, "MDIO read error\n");
+ return 0xffff;
+ }
+
+ value = in_be32(®s->mdio_data) & 0xffff;
+ dev_dbg(&bus->dev, "read %04x\n", value);
+
+ return value;
+}
+
+/* Reset the MIIM registers, and wait for the bus to free */
+static int xgmac_mdio_reset(struct mii_bus *bus)
+{
+ struct tgec_mdio_controller __iomem *regs = bus->priv;
+ int ret;
+
+ mutex_lock(&bus->mdio_lock);
+
+ /* Setup the MII Mgmt clock speed */
+ out_be32(®s->mdio_stat, MDIO_STAT_CLKDIV(100));
+
+ ret = xgmac_wait_until_free(&bus->dev, regs);
+
+ mutex_unlock(&bus->mdio_lock);
+
+ return ret;
+}
+
+static int __devinit xgmac_mdio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct mii_bus *bus;
+ struct resource res;
+ int ret;
+
+ ret = of_address_to_resource(np, 0, &res);
+ if (ret) {
+ dev_err(&pdev->dev, "could not obtain address\n");
+ return ret;
+ }
+
+ bus = mdiobus_alloc_size(PHY_MAX_ADDR * sizeof(int));
+ if (!bus)
+ return -ENOMEM;
+
+ bus->name = "Freescale XGMAC MDIO Bus";
+ bus->read = xgmac_mdio_read;
+ bus->write = xgmac_mdio_write;
+ bus->reset = xgmac_mdio_reset;
+ bus->irq = bus->priv;
+ bus->parent = &pdev->dev;
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%llx", (unsigned long long)res.start);
+
+ /* Set the PHY base address */
+ bus->priv = of_iomap(np, 0);
+ if (!bus->priv) {
+ ret = -ENOMEM;
+ goto err_ioremap;
+ }
+
+ ret = of_mdiobus_register(bus, np);
+ if (ret) {
+ dev_err(&pdev->dev, "cannot register MDIO bus\n");
+ goto err_registration;
+ }
+
+ dev_set_drvdata(&pdev->dev, bus);
+
+ return 0;
+
+err_registration:
+ iounmap(bus->priv);
+
+err_ioremap:
+ mdiobus_free(bus);
+
+ return ret;
+}
+
+static int __devexit xgmac_mdio_remove(struct platform_device *pdev)
+{
+ struct mii_bus *bus = dev_get_drvdata(&pdev->dev);
+
+ mdiobus_unregister(bus);
+ iounmap(bus->priv);
+ mdiobus_free(bus);
+
+ return 0;
+}
+
+static struct of_device_id xgmac_mdio_match[] = {
+ {
+ .compatible = "fsl,fman-xmdio",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, xgmac_mdio_match);
+
+static struct platform_driver xgmac_mdio_driver = {
+ .driver = {
+ .name = "fsl-fman_xmdio",
+ .of_match_table = xgmac_mdio_match,
+ },
+ .probe = xgmac_mdio_probe,
+ .remove = xgmac_mdio_remove,
+};
+
+module_platform_driver(xgmac_mdio_driver);
+
+MODULE_DESCRIPTION("Freescale QorIQ 10G MDIO Controller");
+MODULE_LICENSE("GPL v2");