diff options
Diffstat (limited to 'drivers/net/ethernet/freescale/xgmac_mdio.c')
| -rw-r--r-- | drivers/net/ethernet/freescale/xgmac_mdio.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/drivers/net/ethernet/freescale/xgmac_mdio.c b/drivers/net/ethernet/freescale/xgmac_mdio.c new file mode 100644 index 00000000000..0c9d55c862a --- /dev/null +++ b/drivers/net/ethernet/freescale/xgmac_mdio.c @@ -0,0 +1,277 @@ +/* + * 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_address.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, + "Error while reading PHY%d reg at %d.%d\n", + phy_id, dev_addr, regnum); + 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 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; + } + + platform_set_drvdata(pdev, bus); + + return 0; + +err_registration: + iounmap(bus->priv); + +err_ioremap: + mdiobus_free(bus); + + return ret; +} + +static int xgmac_mdio_remove(struct platform_device *pdev) +{ + struct mii_bus *bus = platform_get_drvdata(pdev); + + 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"); |