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");