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path: root/drivers/net/phy/mdio-bcm-iproc.c
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Diffstat (limited to 'drivers/net/phy/mdio-bcm-iproc.c')
-rw-r--r--drivers/net/phy/mdio-bcm-iproc.c213
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");