net/fsl: introduce Freescale 10G MDIO driver

Similar to fsl_pq_mdio.c, this driver is for the 10G MDIO controller on
Freescale Frame Manager Ethernet controllers.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 282 insertions, 0 deletions

diff --git a/drivers/net/ethernet/freescale/Kconfig b/drivers/net/ethernet/freescale/Kconfig
index 3574e1499dfc..feff51664dcf 100644
--- a/drivers/net/ethernet/freescale/Kconfig
+++ b/drivers/net/ethernet/freescale/Kconfig
@@ -62,6 +62,13 @@ config FSL_PQ_MDIO
         ---help---
           This driver supports the MDIO bus used by the gianfar and UCC drivers.
 
+config FSL_XGMAC_MDIO
+        tristate "Freescale XGMAC MDIO"
+        depends on FSL_SOC
+        select PHYLIB
+        ---help---
+          This driver supports the MDIO bus on the Fman 10G Ethernet MACs.
+
 config UCC_GETH
         tristate "Freescale QE Gigabit Ethernet"
         depends on QUICC_ENGINE
diff --git a/drivers/net/ethernet/freescale/Makefile b/drivers/net/ethernet/freescale/Makefile
index 1752488c9ee5..3d1839afff65 100644
--- a/drivers/net/ethernet/freescale/Makefile
+++ b/drivers/net/ethernet/freescale/Makefile
@@ -9,6 +9,7 @@ ifeq ($(CONFIG_FEC_MPC52xx_MDIO),y)
 endif
 obj-$(CONFIG_FS_ENET) += fs_enet/
 obj-$(CONFIG_FSL_PQ_MDIO) += fsl_pq_mdio.o
+obj-$(CONFIG_FSL_XGMAC_MDIO) += xgmac_mdio.o
 obj-$(CONFIG_GIANFAR) += gianfar_driver.o
 obj-$(CONFIG_PTP_1588_CLOCK_GIANFAR) += gianfar_ptp.o
 gianfar_driver-objs := gianfar.o \
diff --git a/drivers/net/ethernet/freescale/xgmac_mdio.c b/drivers/net/ethernet/freescale/xgmac_mdio.c
new file mode 100644
index 000000000000..1afb5ea2a984
--- /dev/null
+++ b/drivers/net/ethernet/freescale/xgmac_mdio.c
@@ -0,0 +1,274 @@
+/*
+ * 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(&regs->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(&regs->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(&regs->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(&regs->mdio_ctl,
+                 MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr));
+
+        /* Set the register address */
+        out_be32(&regs->mdio_addr, regnum & 0xffff);
+
+        ret = xgmac_wait_until_free(&bus->dev, regs);
+        if (ret)
+                return ret;
+
+        /* Write the value to the register */
+        out_be32(&regs->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(&regs->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(&regs->mdio_ctl, mdio_ctl);
+
+        /* Set the register address */
+        out_be32(&regs->mdio_addr, regnum & 0xffff);
+
+        ret = xgmac_wait_until_free(&bus->dev, regs);
+        if (ret)
+                return ret;
+
+        /* Initiate the read */
+        out_be32(&regs->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(&regs->mdio_stat) & MDIO_STAT_RD_ER) {
+                dev_err(&bus->dev, "MDIO read error\n");
+                return 0xffff;
+        }
+
+        value = in_be32(&regs->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(&regs->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");