diff options
Diffstat (limited to 'drivers/net/phy/mdio-mux-bcm-iproc.c')
| -rw-r--r-- | drivers/net/phy/mdio-mux-bcm-iproc.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio-mux-bcm-iproc.c b/drivers/net/phy/mdio-mux-bcm-iproc.c new file mode 100644 index 000000000000..0a0412524cec --- /dev/null +++ b/drivers/net/phy/mdio-mux-bcm-iproc.c @@ -0,0 +1,248 @@ +/* + * Copyright 2016 Broadcom + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation (the "GPL"). + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License version 2 (GPLv2) for more details. + * + * You should have received a copy of the GNU General Public License + * version 2 (GPLv2) along with this source code. + */ + +#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> + +#define MDIO_PARAM_OFFSET 0x00 +#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 0x04 +#define MDIO_READ_DATA_MASK 0xffff +#define MDIO_ADDR_OFFSET 0x08 + +#define MDIO_CTRL_OFFSET 0x0C +#define MDIO_CTRL_WRITE_OP 0x1 +#define MDIO_CTRL_READ_OP 0x2 + +#define MDIO_STAT_OFFSET 0x10 +#define MDIO_STAT_DONE 1 + +#define BUS_MAX_ADDR 32 +#define EXT_BUS_START_ADDR 16 + +struct iproc_mdiomux_desc { + void *mux_handle; + void __iomem *base; + struct device *dev; + struct mii_bus *mii_bus; +}; + +static int iproc_mdio_wait_for_idle(void __iomem *base, bool result) +{ + unsigned int timeout = 1000; /* loop for 1s */ + u32 val; + + do { + val = readl(base + MDIO_STAT_OFFSET); + if ((val & MDIO_STAT_DONE) == result) + return 0; + + usleep_range(1000, 2000); + } while (timeout--); + + return -ETIMEDOUT; +} + +/* 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); + 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 = mdiobus_alloc(); + if (!md->mii_bus) { + dev_err(&pdev->dev, "mdiomux bus alloc failed\n"); + return -ENOMEM; + } + + 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; + } + + platform_set_drvdata(pdev, md); + + rc = mdio_mux_init(md->dev, mdio_mux_iproc_switch_fn, + &md->mux_handle, md, md->mii_bus); + if (rc) { + dev_info(md->dev, "mdiomux initialization failed\n"); + goto out; + } + + dev_info(md->dev, "iProc mdiomux registered\n"); + return 0; +out: + mdiobus_free(bus); + return rc; +} + +static int mdio_mux_iproc_remove(struct platform_device *pdev) +{ + struct iproc_mdiomux_desc *md = dev_get_platdata(&pdev->dev); + + mdio_mux_uninit(md->mux_handle); + mdiobus_unregister(md->mii_bus); + mdiobus_free(md->mii_bus); + + return 0; +} + +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, + }, + .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"); |