diff options
Diffstat (limited to 'drivers/net/ethernet/qualcomm/emac/emac-phy.c')
| -rw-r--r-- | drivers/net/ethernet/qualcomm/emac/emac-phy.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/net/ethernet/qualcomm/emac/emac-phy.c b/drivers/net/ethernet/qualcomm/emac/emac-phy.c new file mode 100644 index 000000000..5c94af7bb --- /dev/null +++ b/drivers/net/ethernet/qualcomm/emac/emac-phy.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved. + */ + +/* Qualcomm Technologies, Inc. EMAC PHY Controller driver. + */ + +#include <linux/of_mdio.h> +#include <linux/phy.h> +#include <linux/iopoll.h> +#include <linux/acpi.h> +#include "emac.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 MDIO_STATUS_DELAY_TIME 1 + +static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum) +{ + struct emac_adapter *adpt = bus->priv; + u32 reg; + + 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)), + MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100)) + return -EIO; + + return (reg >> MDIO_DATA_SHFT) & MDIO_DATA_BMSK; +} + +static int emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val) +{ + struct emac_adapter *adpt = bus->priv; + u32 reg; + + 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)), + MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100)) + return -EIO; + + return 0; +} + +/* 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; +} |