b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | /* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved. |
| 3 | */ |
| 4 | |
| 5 | /* Qualcomm Technologies, Inc. EMAC PHY Controller driver. |
| 6 | */ |
| 7 | |
| 8 | #include <linux/of_mdio.h> |
| 9 | #include <linux/phy.h> |
| 10 | #include <linux/iopoll.h> |
| 11 | #include <linux/acpi.h> |
| 12 | #include "emac.h" |
| 13 | |
| 14 | /* EMAC base register offsets */ |
| 15 | #define EMAC_MDIO_CTRL 0x001414 |
| 16 | #define EMAC_PHY_STS 0x001418 |
| 17 | #define EMAC_MDIO_EX_CTRL 0x001440 |
| 18 | |
| 19 | /* EMAC_MDIO_CTRL */ |
| 20 | #define MDIO_MODE BIT(30) |
| 21 | #define MDIO_PR BIT(29) |
| 22 | #define MDIO_AP_EN BIT(28) |
| 23 | #define MDIO_BUSY BIT(27) |
| 24 | #define MDIO_CLK_SEL_BMSK 0x7000000 |
| 25 | #define MDIO_CLK_SEL_SHFT 24 |
| 26 | #define MDIO_START BIT(23) |
| 27 | #define SUP_PREAMBLE BIT(22) |
| 28 | #define MDIO_RD_NWR BIT(21) |
| 29 | #define MDIO_REG_ADDR_BMSK 0x1f0000 |
| 30 | #define MDIO_REG_ADDR_SHFT 16 |
| 31 | #define MDIO_DATA_BMSK 0xffff |
| 32 | #define MDIO_DATA_SHFT 0 |
| 33 | |
| 34 | /* EMAC_PHY_STS */ |
| 35 | #define PHY_ADDR_BMSK 0x1f0000 |
| 36 | #define PHY_ADDR_SHFT 16 |
| 37 | |
| 38 | #define MDIO_CLK_25_4 0 |
| 39 | #define MDIO_CLK_25_28 7 |
| 40 | |
| 41 | #define MDIO_WAIT_TIMES 1000 |
| 42 | #define MDIO_STATUS_DELAY_TIME 1 |
| 43 | |
| 44 | static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum) |
| 45 | { |
| 46 | struct emac_adapter *adpt = bus->priv; |
| 47 | u32 reg; |
| 48 | |
| 49 | emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK, |
| 50 | (addr << PHY_ADDR_SHFT)); |
| 51 | |
| 52 | reg = SUP_PREAMBLE | |
| 53 | ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) | |
| 54 | ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) | |
| 55 | MDIO_START | MDIO_RD_NWR; |
| 56 | |
| 57 | writel(reg, adpt->base + EMAC_MDIO_CTRL); |
| 58 | |
| 59 | if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg, |
| 60 | !(reg & (MDIO_START | MDIO_BUSY)), |
| 61 | MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100)) |
| 62 | return -EIO; |
| 63 | |
| 64 | return (reg >> MDIO_DATA_SHFT) & MDIO_DATA_BMSK; |
| 65 | } |
| 66 | |
| 67 | static int emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val) |
| 68 | { |
| 69 | struct emac_adapter *adpt = bus->priv; |
| 70 | u32 reg; |
| 71 | |
| 72 | emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK, |
| 73 | (addr << PHY_ADDR_SHFT)); |
| 74 | |
| 75 | reg = SUP_PREAMBLE | |
| 76 | ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) | |
| 77 | ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) | |
| 78 | ((val << MDIO_DATA_SHFT) & MDIO_DATA_BMSK) | |
| 79 | MDIO_START; |
| 80 | |
| 81 | writel(reg, adpt->base + EMAC_MDIO_CTRL); |
| 82 | |
| 83 | if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg, |
| 84 | !(reg & (MDIO_START | MDIO_BUSY)), |
| 85 | MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100)) |
| 86 | return -EIO; |
| 87 | |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | /* Configure the MDIO bus and connect the external PHY */ |
| 92 | int emac_phy_config(struct platform_device *pdev, struct emac_adapter *adpt) |
| 93 | { |
| 94 | struct device_node *np = pdev->dev.of_node; |
| 95 | struct mii_bus *mii_bus; |
| 96 | int ret; |
| 97 | |
| 98 | /* Create the mii_bus object for talking to the MDIO bus */ |
| 99 | adpt->mii_bus = mii_bus = devm_mdiobus_alloc(&pdev->dev); |
| 100 | if (!mii_bus) |
| 101 | return -ENOMEM; |
| 102 | |
| 103 | mii_bus->name = "emac-mdio"; |
| 104 | snprintf(mii_bus->id, MII_BUS_ID_SIZE, "%s", pdev->name); |
| 105 | mii_bus->read = emac_mdio_read; |
| 106 | mii_bus->write = emac_mdio_write; |
| 107 | mii_bus->parent = &pdev->dev; |
| 108 | mii_bus->priv = adpt; |
| 109 | |
| 110 | if (has_acpi_companion(&pdev->dev)) { |
| 111 | u32 phy_addr; |
| 112 | |
| 113 | ret = mdiobus_register(mii_bus); |
| 114 | if (ret) { |
| 115 | dev_err(&pdev->dev, "could not register mdio bus\n"); |
| 116 | return ret; |
| 117 | } |
| 118 | ret = device_property_read_u32(&pdev->dev, "phy-channel", |
| 119 | &phy_addr); |
| 120 | if (ret) |
| 121 | /* If we can't read a valid phy address, then assume |
| 122 | * that there is only one phy on this mdio bus. |
| 123 | */ |
| 124 | adpt->phydev = phy_find_first(mii_bus); |
| 125 | else |
| 126 | adpt->phydev = mdiobus_get_phy(mii_bus, phy_addr); |
| 127 | |
| 128 | /* of_phy_find_device() claims a reference to the phydev, |
| 129 | * so we do that here manually as well. When the driver |
| 130 | * later unloads, it can unilaterally drop the reference |
| 131 | * without worrying about ACPI vs DT. |
| 132 | */ |
| 133 | if (adpt->phydev) |
| 134 | get_device(&adpt->phydev->mdio.dev); |
| 135 | } else { |
| 136 | struct device_node *phy_np; |
| 137 | |
| 138 | ret = of_mdiobus_register(mii_bus, np); |
| 139 | if (ret) { |
| 140 | dev_err(&pdev->dev, "could not register mdio bus\n"); |
| 141 | return ret; |
| 142 | } |
| 143 | |
| 144 | phy_np = of_parse_phandle(np, "phy-handle", 0); |
| 145 | adpt->phydev = of_phy_find_device(phy_np); |
| 146 | of_node_put(phy_np); |
| 147 | } |
| 148 | |
| 149 | if (!adpt->phydev) { |
| 150 | dev_err(&pdev->dev, "could not find external phy\n"); |
| 151 | mdiobus_unregister(mii_bus); |
| 152 | return -ENODEV; |
| 153 | } |
| 154 | |
| 155 | return 0; |
| 156 | } |