diff options
Diffstat (limited to 'drivers/net/phy/mdio-bcm-iproc.c')
| -rw-r--r-- | drivers/net/phy/mdio-bcm-iproc.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio-bcm-iproc.c b/drivers/net/phy/mdio-bcm-iproc.c new file mode 100644 index 000000000..c0b4e6526 --- /dev/null +++ b/drivers/net/phy/mdio-bcm-iproc.c @@ -0,0 +1,213 @@ +/* + * Copyright (C) 2015 Broadcom Corporation + * + * 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 version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/of_mdio.h> +#include <linux/phy.h> +#include <linux/platform_device.h> +#include <linux/sched.h> + +#define IPROC_GPHY_MDCDIV 0x1a + +#define MII_CTRL_OFFSET 0x000 + +#define MII_CTRL_DIV_SHIFT 0 +#define MII_CTRL_PRE_SHIFT 7 +#define MII_CTRL_BUSY_SHIFT 8 + +#define MII_DATA_OFFSET 0x004 +#define MII_DATA_MASK 0xffff +#define MII_DATA_TA_SHIFT 16 +#define MII_DATA_TA_VAL 2 +#define MII_DATA_RA_SHIFT 18 +#define MII_DATA_PA_SHIFT 23 +#define MII_DATA_OP_SHIFT 28 +#define MII_DATA_OP_WRITE 1 +#define MII_DATA_OP_READ 2 +#define MII_DATA_SB_SHIFT 30 + +struct iproc_mdio_priv { + struct mii_bus *mii_bus; + void __iomem *base; +}; + +static inline int iproc_mdio_wait_for_idle(void __iomem *base) +{ + u32 val; + unsigned int timeout = 1000; /* loop for 1s */ + + do { + val = readl(base + MII_CTRL_OFFSET); + if ((val & BIT(MII_CTRL_BUSY_SHIFT)) == 0) + return 0; + + usleep_range(1000, 2000); + } while (timeout--); + + return -ETIMEDOUT; +} + +static inline void iproc_mdio_config_clk(void __iomem *base) +{ + u32 val; + + val = (IPROC_GPHY_MDCDIV << MII_CTRL_DIV_SHIFT) | + BIT(MII_CTRL_PRE_SHIFT); + writel(val, base + MII_CTRL_OFFSET); +} + +static int iproc_mdio_read(struct mii_bus *bus, int phy_id, int reg) +{ + struct iproc_mdio_priv *priv = bus->priv; + u32 cmd; + int rc; + + rc = iproc_mdio_wait_for_idle(priv->base); + if (rc) + return rc; + + iproc_mdio_config_clk(priv->base); + + /* Prepare the read operation */ + cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) | + (reg << MII_DATA_RA_SHIFT) | + (phy_id << MII_DATA_PA_SHIFT) | + BIT(MII_DATA_SB_SHIFT) | + (MII_DATA_OP_READ << MII_DATA_OP_SHIFT); + + writel(cmd, priv->base + MII_DATA_OFFSET); + + rc = iproc_mdio_wait_for_idle(priv->base); + if (rc) + return rc; + + cmd = readl(priv->base + MII_DATA_OFFSET) & MII_DATA_MASK; + + return cmd; +} + +static int iproc_mdio_write(struct mii_bus *bus, int phy_id, + int reg, u16 val) +{ + struct iproc_mdio_priv *priv = bus->priv; + u32 cmd; + int rc; + + rc = iproc_mdio_wait_for_idle(priv->base); + if (rc) + return rc; + + iproc_mdio_config_clk(priv->base); + + /* Prepare the write operation */ + cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) | + (reg << MII_DATA_RA_SHIFT) | + (phy_id << MII_DATA_PA_SHIFT) | + BIT(MII_DATA_SB_SHIFT) | + (MII_DATA_OP_WRITE << MII_DATA_OP_SHIFT) | + ((u32)(val) & MII_DATA_MASK); + + writel(cmd, priv->base + MII_DATA_OFFSET); + + rc = iproc_mdio_wait_for_idle(priv->base); + if (rc) + return rc; + + return 0; +} + +static int iproc_mdio_probe(struct platform_device *pdev) +{ + struct iproc_mdio_priv *priv; + struct mii_bus *bus; + struct resource *res; + int rc; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->base)) { + dev_err(&pdev->dev, "failed to ioremap register\n"); + return PTR_ERR(priv->base); + } + + priv->mii_bus = mdiobus_alloc(); + if (!priv->mii_bus) { + dev_err(&pdev->dev, "MDIO bus alloc failed\n"); + return -ENOMEM; + } + + bus = priv->mii_bus; + bus->priv = priv; + bus->name = "iProc MDIO bus"; + snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id); + bus->parent = &pdev->dev; + bus->read = iproc_mdio_read; + bus->write = iproc_mdio_write; + + rc = of_mdiobus_register(bus, pdev->dev.of_node); + if (rc) { + dev_err(&pdev->dev, "MDIO bus registration failed\n"); + goto err_iproc_mdio; + } + + platform_set_drvdata(pdev, priv); + + dev_info(&pdev->dev, "Broadcom iProc MDIO bus at 0x%p\n", priv->base); + + return 0; + +err_iproc_mdio: + mdiobus_free(bus); + return rc; +} + +static int iproc_mdio_remove(struct platform_device *pdev) +{ + struct iproc_mdio_priv *priv = platform_get_drvdata(pdev); + + mdiobus_unregister(priv->mii_bus); + mdiobus_free(priv->mii_bus); + + return 0; +} + +static const struct of_device_id iproc_mdio_of_match[] = { + { .compatible = "brcm,iproc-mdio", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, iproc_mdio_of_match); + +static struct platform_driver iproc_mdio_driver = { + .driver = { + .name = "iproc-mdio", + .of_match_table = iproc_mdio_of_match, + }, + .probe = iproc_mdio_probe, + .remove = iproc_mdio_remove, +}; + +module_platform_driver(iproc_mdio_driver); + +MODULE_AUTHOR("Broadcom Corporation"); +MODULE_DESCRIPTION("Broadcom iProc MDIO bus controller"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:iproc-mdio"); |