diff options
Diffstat (limited to 'drivers/net/ethernet/hisilicon/hip04_mdio.c')
| -rw-r--r-- | drivers/net/ethernet/hisilicon/hip04_mdio.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/net/ethernet/hisilicon/hip04_mdio.c b/drivers/net/ethernet/hisilicon/hip04_mdio.c new file mode 100644 index 000000000000..b3bac25db99c --- /dev/null +++ b/drivers/net/ethernet/hisilicon/hip04_mdio.c @@ -0,0 +1,186 @@ +/* Copyright (c) 2014 Linaro Ltd. + * Copyright (c) 2014 Hisilicon Limited. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/of_mdio.h> +#include <linux/delay.h> + +#define MDIO_CMD_REG 0x0 +#define MDIO_ADDR_REG 0x4 +#define MDIO_WDATA_REG 0x8 +#define MDIO_RDATA_REG 0xc +#define MDIO_STA_REG 0x10 + +#define MDIO_START BIT(14) +#define MDIO_R_VALID BIT(1) +#define MDIO_READ (BIT(12) | BIT(11) | MDIO_START) +#define MDIO_WRITE (BIT(12) | BIT(10) | MDIO_START) + +struct hip04_mdio_priv { + void __iomem *base; +}; + +#define WAIT_TIMEOUT 10 +static int hip04_mdio_wait_ready(struct mii_bus *bus) +{ + struct hip04_mdio_priv *priv = bus->priv; + int i; + + for (i = 0; readl_relaxed(priv->base + MDIO_CMD_REG) & MDIO_START; i++) { + if (i == WAIT_TIMEOUT) + return -ETIMEDOUT; + msleep(20); + } + + return 0; +} + +static int hip04_mdio_read(struct mii_bus *bus, int mii_id, int regnum) +{ + struct hip04_mdio_priv *priv = bus->priv; + u32 val; + int ret; + + ret = hip04_mdio_wait_ready(bus); + if (ret < 0) + goto out; + + val = regnum | (mii_id << 5) | MDIO_READ; + writel_relaxed(val, priv->base + MDIO_CMD_REG); + + ret = hip04_mdio_wait_ready(bus); + if (ret < 0) + goto out; + + val = readl_relaxed(priv->base + MDIO_STA_REG); + if (val & MDIO_R_VALID) { + dev_err(bus->parent, "SMI bus read not valid\n"); + ret = -ENODEV; + goto out; + } + + val = readl_relaxed(priv->base + MDIO_RDATA_REG); + ret = val & 0xFFFF; +out: + return ret; +} + +static int hip04_mdio_write(struct mii_bus *bus, int mii_id, + int regnum, u16 value) +{ + struct hip04_mdio_priv *priv = bus->priv; + u32 val; + int ret; + + ret = hip04_mdio_wait_ready(bus); + if (ret < 0) + goto out; + + writel_relaxed(value, priv->base + MDIO_WDATA_REG); + val = regnum | (mii_id << 5) | MDIO_WRITE; + writel_relaxed(val, priv->base + MDIO_CMD_REG); +out: + return ret; +} + +static int hip04_mdio_reset(struct mii_bus *bus) +{ + int temp, i; + + for (i = 0; i < PHY_MAX_ADDR; i++) { + hip04_mdio_write(bus, i, 22, 0); + temp = hip04_mdio_read(bus, i, MII_BMCR); + if (temp < 0) + continue; + + temp |= BMCR_RESET; + if (hip04_mdio_write(bus, i, MII_BMCR, temp) < 0) + continue; + } + + mdelay(500); + return 0; +} + +static int hip04_mdio_probe(struct platform_device *pdev) +{ + struct resource *r; + struct mii_bus *bus; + struct hip04_mdio_priv *priv; + int ret; + + bus = mdiobus_alloc_size(sizeof(struct hip04_mdio_priv)); + if (!bus) { + dev_err(&pdev->dev, "Cannot allocate MDIO bus\n"); + return -ENOMEM; + } + + bus->name = "hip04_mdio_bus"; + bus->read = hip04_mdio_read; + bus->write = hip04_mdio_write; + bus->reset = hip04_mdio_reset; + snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev)); + bus->parent = &pdev->dev; + priv = bus->priv; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(priv->base)) { + ret = PTR_ERR(priv->base); + goto out_mdio; + } + + ret = of_mdiobus_register(bus, pdev->dev.of_node); + if (ret < 0) { + dev_err(&pdev->dev, "Cannot register MDIO bus (%d)\n", ret); + goto out_mdio; + } + + platform_set_drvdata(pdev, bus); + + return 0; + +out_mdio: + mdiobus_free(bus); + return ret; +} + +static int hip04_mdio_remove(struct platform_device *pdev) +{ + struct mii_bus *bus = platform_get_drvdata(pdev); + + mdiobus_unregister(bus); + mdiobus_free(bus); + + return 0; +} + +static const struct of_device_id hip04_mdio_match[] = { + { .compatible = "hisilicon,hip04-mdio" }, + { } +}; +MODULE_DEVICE_TABLE(of, hip04_mdio_match); + +static struct platform_driver hip04_mdio_driver = { + .probe = hip04_mdio_probe, + .remove = hip04_mdio_remove, + .driver = { + .name = "hip04-mdio", + .owner = THIS_MODULE, + .of_match_table = hip04_mdio_match, + }, +}; + +module_platform_driver(hip04_mdio_driver); + +MODULE_DESCRIPTION("HISILICON P04 MDIO interface driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:hip04-mdio"); |