| /* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 and |
| * only version 2 as published by the Free Software Foundation. |
| * |
| * 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 for more details. |
| */ |
| |
| /* Qualcomm Technologies, Inc. EMAC PHY Controller driver. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/of_net.h> |
| #include <linux/of_mdio.h> |
| #include <linux/phy.h> |
| #include <linux/iopoll.h> |
| #include <linux/acpi.h> |
| #include "emac.h" |
| #include "emac-mac.h" |
| |
| /* EMAC base register offsets */ |
| #define EMAC_MDIO_CTRL 0x001414 |
| #define EMAC_PHY_STS 0x001418 |
| #define EMAC_MDIO_EX_CTRL 0x001440 |
| |
| /* EMAC_MDIO_CTRL */ |
| #define MDIO_MODE BIT(30) |
| #define MDIO_PR BIT(29) |
| #define MDIO_AP_EN BIT(28) |
| #define MDIO_BUSY BIT(27) |
| #define MDIO_CLK_SEL_BMSK 0x7000000 |
| #define MDIO_CLK_SEL_SHFT 24 |
| #define MDIO_START BIT(23) |
| #define SUP_PREAMBLE BIT(22) |
| #define MDIO_RD_NWR BIT(21) |
| #define MDIO_REG_ADDR_BMSK 0x1f0000 |
| #define MDIO_REG_ADDR_SHFT 16 |
| #define MDIO_DATA_BMSK 0xffff |
| #define MDIO_DATA_SHFT 0 |
| |
| /* EMAC_PHY_STS */ |
| #define PHY_ADDR_BMSK 0x1f0000 |
| #define PHY_ADDR_SHFT 16 |
| |
| #define MDIO_CLK_25_4 0 |
| #define MDIO_CLK_25_28 7 |
| |
| #define MDIO_WAIT_TIMES 1000 |
| |
| #define EMAC_LINK_SPEED_DEFAULT (\ |
| EMAC_LINK_SPEED_10_HALF |\ |
| EMAC_LINK_SPEED_10_FULL |\ |
| EMAC_LINK_SPEED_100_HALF |\ |
| EMAC_LINK_SPEED_100_FULL |\ |
| EMAC_LINK_SPEED_1GB_FULL) |
| |
| /** |
| * emac_phy_mdio_autopoll_disable() - disable mdio autopoll |
| * @adpt: the emac adapter |
| * |
| * The autopoll feature takes over the MDIO bus. In order for |
| * the PHY driver to be able to talk to the PHY over the MDIO |
| * bus, we need to temporarily disable the autopoll feature. |
| */ |
| static int emac_phy_mdio_autopoll_disable(struct emac_adapter *adpt) |
| { |
| u32 val; |
| |
| /* disable autopoll */ |
| emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, MDIO_AP_EN, 0); |
| |
| /* wait for any mdio polling to complete */ |
| if (!readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, val, |
| !(val & MDIO_BUSY), 100, MDIO_WAIT_TIMES * 100)) |
| return 0; |
| |
| /* failed to disable; ensure it is enabled before returning */ |
| emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, 0, MDIO_AP_EN); |
| |
| return -EBUSY; |
| } |
| |
| /** |
| * emac_phy_mdio_autopoll_disable() - disable mdio autopoll |
| * @adpt: the emac adapter |
| * |
| * The EMAC has the ability to poll the external PHY on the MDIO |
| * bus for link state changes. This eliminates the need for the |
| * driver to poll the phy. If if the link state does change, |
| * the EMAC issues an interrupt on behalf of the PHY. |
| */ |
| static void emac_phy_mdio_autopoll_enable(struct emac_adapter *adpt) |
| { |
| emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, 0, MDIO_AP_EN); |
| } |
| |
| static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum) |
| { |
| struct emac_adapter *adpt = bus->priv; |
| u32 reg; |
| int ret; |
| |
| ret = emac_phy_mdio_autopoll_disable(adpt); |
| if (ret) |
| return ret; |
| |
| emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK, |
| (addr << PHY_ADDR_SHFT)); |
| |
| reg = SUP_PREAMBLE | |
| ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) | |
| ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) | |
| MDIO_START | MDIO_RD_NWR; |
| |
| writel(reg, adpt->base + EMAC_MDIO_CTRL); |
| |
| if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg, |
| !(reg & (MDIO_START | MDIO_BUSY)), |
| 100, MDIO_WAIT_TIMES * 100)) |
| ret = -EIO; |
| else |
| ret = (reg >> MDIO_DATA_SHFT) & MDIO_DATA_BMSK; |
| |
| emac_phy_mdio_autopoll_enable(adpt); |
| |
| return ret; |
| } |
| |
| static int emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val) |
| { |
| struct emac_adapter *adpt = bus->priv; |
| u32 reg; |
| int ret; |
| |
| ret = emac_phy_mdio_autopoll_disable(adpt); |
| if (ret) |
| return ret; |
| |
| emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK, |
| (addr << PHY_ADDR_SHFT)); |
| |
| reg = SUP_PREAMBLE | |
| ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) | |
| ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) | |
| ((val << MDIO_DATA_SHFT) & MDIO_DATA_BMSK) | |
| MDIO_START; |
| |
| writel(reg, adpt->base + EMAC_MDIO_CTRL); |
| |
| if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg, |
| !(reg & (MDIO_START | MDIO_BUSY)), 100, |
| MDIO_WAIT_TIMES * 100)) |
| ret = -EIO; |
| |
| emac_phy_mdio_autopoll_enable(adpt); |
| |
| return ret; |
| } |
| |
| /* Configure the MDIO bus and connect the external PHY */ |
| int emac_phy_config(struct platform_device *pdev, struct emac_adapter *adpt) |
| { |
| struct device_node *np = pdev->dev.of_node; |
| struct mii_bus *mii_bus; |
| int ret; |
| |
| /* Create the mii_bus object for talking to the MDIO bus */ |
| adpt->mii_bus = mii_bus = devm_mdiobus_alloc(&pdev->dev); |
| if (!mii_bus) |
| return -ENOMEM; |
| |
| mii_bus->name = "emac-mdio"; |
| snprintf(mii_bus->id, MII_BUS_ID_SIZE, "%s", pdev->name); |
| mii_bus->read = emac_mdio_read; |
| mii_bus->write = emac_mdio_write; |
| mii_bus->parent = &pdev->dev; |
| mii_bus->priv = adpt; |
| |
| if (has_acpi_companion(&pdev->dev)) { |
| u32 phy_addr; |
| |
| ret = mdiobus_register(mii_bus); |
| if (ret) { |
| dev_err(&pdev->dev, "could not register mdio bus\n"); |
| return ret; |
| } |
| ret = device_property_read_u32(&pdev->dev, "phy-channel", |
| &phy_addr); |
| if (ret) |
| /* If we can't read a valid phy address, then assume |
| * that there is only one phy on this mdio bus. |
| */ |
| adpt->phydev = phy_find_first(mii_bus); |
| else |
| adpt->phydev = mdiobus_get_phy(mii_bus, phy_addr); |
| |
| /* of_phy_find_device() claims a reference to the phydev, |
| * so we do that here manually as well. When the driver |
| * later unloads, it can unilaterally drop the reference |
| * without worrying about ACPI vs DT. |
| */ |
| if (adpt->phydev) |
| get_device(&adpt->phydev->mdio.dev); |
| } else { |
| struct device_node *phy_np; |
| |
| ret = of_mdiobus_register(mii_bus, np); |
| if (ret) { |
| dev_err(&pdev->dev, "could not register mdio bus\n"); |
| return ret; |
| } |
| |
| phy_np = of_parse_phandle(np, "phy-handle", 0); |
| adpt->phydev = of_phy_find_device(phy_np); |
| of_node_put(phy_np); |
| } |
| |
| if (!adpt->phydev) { |
| dev_err(&pdev->dev, "could not find external phy\n"); |
| mdiobus_unregister(mii_bus); |
| return -ENODEV; |
| } |
| |
| return 0; |
| } |