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path: root/drivers/net/mdio/mdio-mux-bcm-iproc.c
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Diffstat (limited to 'drivers/net/mdio/mdio-mux-bcm-iproc.c')
-rw-r--r--drivers/net/mdio/mdio-mux-bcm-iproc.c320
1 files changed, 320 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 000000000..014c0baed
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-bcm-iproc.c
@@ -0,0 +1,320 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2016 Broadcom
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/iopoll.h>
+#include <linux/mdio-mux.h>
+#include <linux/module.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.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 derive 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;
+
+ md->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(md->base))
+ return PTR_ERR(md->base);
+ 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->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");