--- /dev/null
+/*
+ * 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 const 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",
+ .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");
Code Review / kvmfornfv.git / blobdiff