diff options
Diffstat (limited to 'drivers/net/phy/mdio-bcm-unimac.c')
| -rw-r--r-- | drivers/net/phy/mdio-bcm-unimac.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio-bcm-unimac.c b/drivers/net/phy/mdio-bcm-unimac.c new file mode 100644 index 000000000000..5b643e588e8f --- /dev/null +++ b/drivers/net/phy/mdio-bcm-unimac.c @@ -0,0 +1,213 @@ +/* + * Broadcom UniMAC MDIO bus controller driver + * + * Copyright (C) 2014, 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; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/kernel.h> +#include <linux/phy.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/delay.h> + +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/of_mdio.h> + +#define MDIO_CMD 0x00 +#define MDIO_START_BUSY (1 << 29) +#define MDIO_READ_FAIL (1 << 28) +#define MDIO_RD (2 << 26) +#define MDIO_WR (1 << 26) +#define MDIO_PMD_SHIFT 21 +#define MDIO_PMD_MASK 0x1F +#define MDIO_REG_SHIFT 16 +#define MDIO_REG_MASK 0x1F + +#define MDIO_CFG 0x04 +#define MDIO_C22 (1 << 0) +#define MDIO_C45 0 +#define MDIO_CLK_DIV_SHIFT 4 +#define MDIO_CLK_DIV_MASK 0x3F +#define MDIO_SUPP_PREAMBLE (1 << 12) + +struct unimac_mdio_priv { + struct mii_bus *mii_bus; + void __iomem *base; +}; + +static inline void unimac_mdio_start(struct unimac_mdio_priv *priv) +{ + u32 reg; + + reg = __raw_readl(priv->base + MDIO_CMD); + reg |= MDIO_START_BUSY; + __raw_writel(reg, priv->base + MDIO_CMD); +} + +static inline unsigned int unimac_mdio_busy(struct unimac_mdio_priv *priv) +{ + return __raw_readl(priv->base + MDIO_CMD) & MDIO_START_BUSY; +} + +static int unimac_mdio_read(struct mii_bus *bus, int phy_id, int reg) +{ + struct unimac_mdio_priv *priv = bus->priv; + unsigned int timeout = 1000; + u32 cmd; + + /* Prepare the read operation */ + cmd = MDIO_RD | (phy_id << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT); + __raw_writel(cmd, priv->base + MDIO_CMD); + + /* Start MDIO transaction */ + unimac_mdio_start(priv); + + do { + if (!unimac_mdio_busy(priv)) + break; + + usleep_range(1000, 2000); + } while (timeout--); + + if (!timeout) + return -ETIMEDOUT; + + cmd = __raw_readl(priv->base + MDIO_CMD); + if (cmd & MDIO_READ_FAIL) + return -EIO; + + return cmd & 0xffff; +} + +static int unimac_mdio_write(struct mii_bus *bus, int phy_id, + int reg, u16 val) +{ + struct unimac_mdio_priv *priv = bus->priv; + unsigned int timeout = 1000; + u32 cmd; + + /* Prepare the write operation */ + cmd = MDIO_WR | (phy_id << MDIO_PMD_SHIFT) | + (reg << MDIO_REG_SHIFT) | (0xffff & val); + __raw_writel(cmd, priv->base + MDIO_CMD); + + unimac_mdio_start(priv); + + do { + if (!unimac_mdio_busy(priv)) + break; + + usleep_range(1000, 2000); + } while (timeout--); + + if (!timeout) + return -ETIMEDOUT; + + return 0; +} + +static int unimac_mdio_probe(struct platform_device *pdev) +{ + struct unimac_mdio_priv *priv; + struct device_node *np; + struct mii_bus *bus; + struct resource *r; + int ret; + + np = pdev->dev.of_node; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + + /* Just ioremap, as this MDIO block is usually integrated into an + * Ethernet MAC controller register range + */ + priv->base = devm_ioremap(&pdev->dev, r->start, resource_size(r)); + if (!priv->base) { + dev_err(&pdev->dev, "failed to remap register\n"); + return -ENOMEM; + } + + priv->mii_bus = mdiobus_alloc(); + if (!priv->mii_bus) + return -ENOMEM; + + bus = priv->mii_bus; + bus->priv = priv; + bus->name = "unimac MII bus"; + bus->parent = &pdev->dev; + bus->read = unimac_mdio_read; + bus->write = unimac_mdio_write; + snprintf(bus->id, MII_BUS_ID_SIZE, "%s", pdev->name); + + bus->irq = kcalloc(PHY_MAX_ADDR, sizeof(int), GFP_KERNEL); + if (!bus->irq) { + ret = -ENOMEM; + goto out_mdio_free; + } + + ret = of_mdiobus_register(bus, np); + if (ret) { + dev_err(&pdev->dev, "MDIO bus registration failed\n"); + goto out_mdio_irq; + } + + platform_set_drvdata(pdev, priv); + + dev_info(&pdev->dev, "Broadcom UniMAC MDIO bus at 0x%p\n", priv->base); + + return 0; + +out_mdio_irq: + kfree(bus->irq); +out_mdio_free: + mdiobus_free(bus); + return ret; +} + +static int unimac_mdio_remove(struct platform_device *pdev) +{ + struct unimac_mdio_priv *priv = platform_get_drvdata(pdev); + + mdiobus_unregister(priv->mii_bus); + kfree(priv->mii_bus->irq); + mdiobus_free(priv->mii_bus); + + return 0; +} + +static struct of_device_id unimac_mdio_ids[] = { + { .compatible = "brcm,genet-mdio-v4", }, + { .compatible = "brcm,genet-mdio-v3", }, + { .compatible = "brcm,genet-mdio-v2", }, + { .compatible = "brcm,genet-mdio-v1", }, + { .compatible = "brcm,unimac-mdio", }, + { /* sentinel */ }, +}; + +static struct platform_driver unimac_mdio_driver = { + .driver = { + .name = "unimac-mdio", + .owner = THIS_MODULE, + .of_match_table = unimac_mdio_ids, + }, + .probe = unimac_mdio_probe, + .remove = unimac_mdio_remove, +}; +module_platform_driver(unimac_mdio_driver); + +MODULE_AUTHOR("Broadcom Corporation"); +MODULE_DESCRIPTION("Broadcom UniMAC MDIO bus controller"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:unimac-mdio"); |