1 files changed, 323 insertions, 0 deletions
diff --git a/drivers/net/mdio/mdio-mux-bcm-iproc.c b/drivers/net/mdio/mdio-mux-bcm-iproc.c
new file mode 100644
index 000000000000..42fb5f166136
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-bcm-iproc.c
@@ -0,0 +1,323 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2016 Broadcom
+ */
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/mdio-mux.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+
+#define MDIO_RATE_ADJ_EXT_OFFSET	0x000
+#define MDIO_RATE_ADJ_INT_OFFSET	0x004
+#define MDIO_RATE_ADJ_DIVIDENT_SHIFT	16
+
+#define MDIO_SCAN_CTRL_OFFSET		0x008
+#define MDIO_SCAN_CTRL_OVRIDE_EXT_MSTR	28
+
+#define MDIO_PARAM_OFFSET		0x23c
+#define MDIO_PARAM_MIIM_CYCLE		29
+#define MDIO_PARAM_INTERNAL_SEL		25
+#define MDIO_PARAM_BUS_ID		22
+#define MDIO_PARAM_C45_SEL		21
+#define MDIO_PARAM_PHY_ID		16
+#define MDIO_PARAM_PHY_DATA		0
+
+#define MDIO_READ_OFFSET		0x240
+#define MDIO_READ_DATA_MASK		0xffff
+#define MDIO_ADDR_OFFSET		0x244
+
+#define MDIO_CTRL_OFFSET		0x248
+#define MDIO_CTRL_WRITE_OP		0x1
+#define MDIO_CTRL_READ_OP		0x2
+
+#define MDIO_STAT_OFFSET		0x24c
+#define MDIO_STAT_DONE			1
+
+#define BUS_MAX_ADDR			32
+#define EXT_BUS_START_ADDR		16
+
+#define MDIO_REG_ADDR_SPACE_SIZE	0x250
+
+#define MDIO_OPERATING_FREQUENCY	11000000
+#define MDIO_RATE_ADJ_DIVIDENT		1
+
+struct iproc_mdiomux_desc {
+	void *mux_handle;
+	void __iomem *base;
+	struct device *dev;
+	struct mii_bus *mii_bus;
+	struct clk *core_clk;
+};
+
+static void mdio_mux_iproc_config(struct iproc_mdiomux_desc *md)
+{
+	u32 divisor;
+	u32 val;
+
+	/* Disable external mdio master access */
+	val = readl(md->base + MDIO_SCAN_CTRL_OFFSET);
+	val |= BIT(MDIO_SCAN_CTRL_OVRIDE_EXT_MSTR);
+	writel(val, md->base + MDIO_SCAN_CTRL_OFFSET);
+
+	if (md->core_clk) {
+		/* use rate adjust regs to derrive the mdio's operating
+		 * frequency from the specified core clock
+		 */
+		divisor = clk_get_rate(md->core_clk) / MDIO_OPERATING_FREQUENCY;
+		divisor = divisor / (MDIO_RATE_ADJ_DIVIDENT + 1);
+		val = divisor;
+		val |= MDIO_RATE_ADJ_DIVIDENT << MDIO_RATE_ADJ_DIVIDENT_SHIFT;
+		writel(val, md->base + MDIO_RATE_ADJ_EXT_OFFSET);
+		writel(val, md->base + MDIO_RATE_ADJ_INT_OFFSET);
+	}
+}
+
+static int iproc_mdio_wait_for_idle(void __iomem *base, bool result)
+{
+	u32 val;
+
+	return readl_poll_timeout(base + MDIO_STAT_OFFSET, val,
+				  (val & MDIO_STAT_DONE) == result,
+				  2000, 1000000);
+}
+
+/* start_miim_ops- Program and start MDIO transaction over mdio bus.
+ * @base: Base address
+ * @phyid: phyid of the selected bus.
+ * @reg: register offset to be read/written.
+ * @val :0 if read op else value to be written in @reg;
+ * @op: Operation that need to be carried out.
+ *      MDIO_CTRL_READ_OP: Read transaction.
+ *      MDIO_CTRL_WRITE_OP: Write transaction.
+ *
+ * Return value: Successful Read operation returns read reg values and write
+ *      operation returns 0. Failure operation returns negative error code.
+ */
+static int start_miim_ops(void __iomem *base,
+			  u16 phyid, u32 reg, u16 val, u32 op)
+{
+	u32 param;
+	int ret;
+
+	writel(0, base + MDIO_CTRL_OFFSET);
+	ret = iproc_mdio_wait_for_idle(base, 0);
+	if (ret)
+		goto err;
+
+	param = readl(base + MDIO_PARAM_OFFSET);
+	param |= phyid << MDIO_PARAM_PHY_ID;
+	param |= val << MDIO_PARAM_PHY_DATA;
+	if (reg & MII_ADDR_C45)
+		param |= BIT(MDIO_PARAM_C45_SEL);
+
+	writel(param, base + MDIO_PARAM_OFFSET);
+
+	writel(reg, base + MDIO_ADDR_OFFSET);
+
+	writel(op, base + MDIO_CTRL_OFFSET);
+
+	ret = iproc_mdio_wait_for_idle(base, 1);
+	if (ret)
+		goto err;
+
+	if (op == MDIO_CTRL_READ_OP)
+		ret = readl(base + MDIO_READ_OFFSET) & MDIO_READ_DATA_MASK;
+err:
+	return ret;
+}
+
+static int iproc_mdiomux_read(struct mii_bus *bus, int phyid, int reg)
+{
+	struct iproc_mdiomux_desc *md = bus->priv;
+	int ret;
+
+	ret = start_miim_ops(md->base, phyid, reg, 0, MDIO_CTRL_READ_OP);
+	if (ret < 0)
+		dev_err(&bus->dev, "mdiomux read operation failed!!!");
+
+	return ret;
+}
+
+static int iproc_mdiomux_write(struct mii_bus *bus,
+			       int phyid, int reg, u16 val)
+{
+	struct iproc_mdiomux_desc *md = bus->priv;
+	int ret;
+
+	/* Write val at reg offset */
+	ret = start_miim_ops(md->base, phyid, reg, val, MDIO_CTRL_WRITE_OP);
+	if (ret < 0)
+		dev_err(&bus->dev, "mdiomux write operation failed!!!");
+
+	return ret;
+}
+
+static int mdio_mux_iproc_switch_fn(int current_child, int desired_child,
+				    void *data)
+{
+	struct iproc_mdiomux_desc *md = data;
+	u32 param, bus_id;
+	bool bus_dir;
+
+	/* select bus and its properties */
+	bus_dir = (desired_child < EXT_BUS_START_ADDR);
+	bus_id = bus_dir ? desired_child : (desired_child - EXT_BUS_START_ADDR);
+
+	param = (bus_dir ? 1 : 0) << MDIO_PARAM_INTERNAL_SEL;
+	param |= (bus_id << MDIO_PARAM_BUS_ID);
+
+	writel(param, md->base + MDIO_PARAM_OFFSET);
+	return 0;
+}
+
+static int mdio_mux_iproc_probe(struct platform_device *pdev)
+{
+	struct iproc_mdiomux_desc *md;
+	struct mii_bus *bus;
+	struct resource *res;
+	int rc;
+
+	md = devm_kzalloc(&pdev->dev, sizeof(*md), GFP_KERNEL);
+	if (!md)
+		return -ENOMEM;
+	md->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res->start & 0xfff) {
+		/* For backward compatibility in case the
+		 * base address is specified with an offset.
+		 */
+		dev_info(&pdev->dev, "fix base address in dt-blob\n");
+		res->start &= ~0xfff;
+		res->end = res->start + MDIO_REG_ADDR_SPACE_SIZE - 1;
+	}
+	md->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(md->base)) {
+		dev_err(&pdev->dev, "failed to ioremap register\n");
+		return PTR_ERR(md->base);
+	}
+
+	md->mii_bus = devm_mdiobus_alloc(&pdev->dev);
+	if (!md->mii_bus) {
+		dev_err(&pdev->dev, "mdiomux bus alloc failed\n");
+		return -ENOMEM;
+	}
+
+	md->core_clk = devm_clk_get(&pdev->dev, NULL);
+	if (md->core_clk == ERR_PTR(-ENOENT) ||
+	    md->core_clk == ERR_PTR(-EINVAL))
+		md->core_clk = NULL;
+	else if (IS_ERR(md->core_clk))
+		return PTR_ERR(md->core_clk);
+
+	rc = clk_prepare_enable(md->core_clk);
+	if (rc) {
+		dev_err(&pdev->dev, "failed to enable core clk\n");
+		return rc;
+	}
+
+	bus = md->mii_bus;
+	bus->priv = md;
+	bus->name = "iProc MDIO mux bus";
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
+	bus->parent = &pdev->dev;
+	bus->read = iproc_mdiomux_read;
+	bus->write = iproc_mdiomux_write;
+
+	bus->phy_mask = ~0;
+	bus->dev.of_node = pdev->dev.of_node;
+	rc = mdiobus_register(bus);
+	if (rc) {
+		dev_err(&pdev->dev, "mdiomux registration failed\n");
+		goto out_clk;
+	}
+
+	platform_set_drvdata(pdev, md);
+
+	rc = mdio_mux_init(md->dev, md->dev->of_node, mdio_mux_iproc_switch_fn,
+			   &md->mux_handle, md, md->mii_bus);
+	if (rc) {
+		dev_info(md->dev, "mdiomux initialization failed\n");
+		goto out_register;
+	}
+
+	mdio_mux_iproc_config(md);
+
+	dev_info(md->dev, "iProc mdiomux registered\n");
+	return 0;
+
+out_register:
+	mdiobus_unregister(bus);
+out_clk:
+	clk_disable_unprepare(md->core_clk);
+	return rc;
+}
+
+static int mdio_mux_iproc_remove(struct platform_device *pdev)
+{
+	struct iproc_mdiomux_desc *md = platform_get_drvdata(pdev);
+
+	mdio_mux_uninit(md->mux_handle);
+	mdiobus_unregister(md->mii_bus);
+	clk_disable_unprepare(md->core_clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mdio_mux_iproc_suspend(struct device *dev)
+{
+	struct iproc_mdiomux_desc *md = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(md->core_clk);
+
+	return 0;
+}
+
+static int mdio_mux_iproc_resume(struct device *dev)
+{
+	struct iproc_mdiomux_desc *md = dev_get_drvdata(dev);
+	int rc;
+
+	rc = clk_prepare_enable(md->core_clk);
+	if (rc) {
+		dev_err(md->dev, "failed to enable core clk\n");
+		return rc;
+	}
+	mdio_mux_iproc_config(md);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mdio_mux_iproc_pm_ops,
+			 mdio_mux_iproc_suspend, mdio_mux_iproc_resume);
+
+static const struct of_device_id mdio_mux_iproc_match[] = {
+	{
+		.compatible = "brcm,mdio-mux-iproc",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mdio_mux_iproc_match);
+
+static struct platform_driver mdiomux_iproc_driver = {
+	.driver = {
+		.name		= "mdio-mux-iproc",
+		.of_match_table = mdio_mux_iproc_match,
+		.pm		= &mdio_mux_iproc_pm_ops,
+	},
+	.probe		= mdio_mux_iproc_probe,
+	.remove		= mdio_mux_iproc_remove,
+};
+
+module_platform_driver(mdiomux_iproc_driver);
+
+MODULE_DESCRIPTION("iProc MDIO Mux Bus Driver");
+MODULE_AUTHOR("Pramod Kumar <pramod.kumar@broadcom.com>");
+MODULE_LICENSE("GPL v2");