// SPDX-License-Identifier: GPL-2.0
/* Driver for the Texas Instruments DP83869 PHY
 * Copyright (C) 2019 Texas Instruments Inc.
 */

#include <linux/ethtool.h>
#include <linux/kernel.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy.h>
#include <linux/delay.h>

#include <dt-bindings/net/ti-dp83869.h>

#define DP83869_PHY_ID		0x2000a0f1
#define DP83869_DEVADDR		0x1f

#define MII_DP83869_PHYCTRL	0x10
#define MII_DP83869_MICR	0x12
#define MII_DP83869_ISR		0x13
#define DP83869_CTRL		0x1f
#define DP83869_CFG4		0x1e

/* Extended Registers */
#define DP83869_GEN_CFG3        0x0031
#define DP83869_RGMIICTL	0x0032
#define DP83869_STRAP_STS1	0x006e
#define DP83869_RGMIIDCTL	0x0086
#define DP83869_IO_MUX_CFG	0x0170
#define DP83869_OP_MODE		0x01df
#define DP83869_FX_CTRL		0x0c00

#define DP83869_SW_RESET	BIT(15)
#define DP83869_SW_RESTART	BIT(14)

/* MICR Interrupt bits */
#define MII_DP83869_MICR_AN_ERR_INT_EN		BIT(15)
#define MII_DP83869_MICR_SPEED_CHNG_INT_EN	BIT(14)
#define MII_DP83869_MICR_DUP_MODE_CHNG_INT_EN	BIT(13)
#define MII_DP83869_MICR_PAGE_RXD_INT_EN	BIT(12)
#define MII_DP83869_MICR_AUTONEG_COMP_INT_EN	BIT(11)
#define MII_DP83869_MICR_LINK_STS_CHNG_INT_EN	BIT(10)
#define MII_DP83869_MICR_FALSE_CARRIER_INT_EN	BIT(8)
#define MII_DP83869_MICR_SLEEP_MODE_CHNG_INT_EN	BIT(4)
#define MII_DP83869_MICR_WOL_INT_EN		BIT(3)
#define MII_DP83869_MICR_XGMII_ERR_INT_EN	BIT(2)
#define MII_DP83869_MICR_POL_CHNG_INT_EN	BIT(1)
#define MII_DP83869_MICR_JABBER_INT_EN		BIT(0)

#define MII_DP83869_BMCR_DEFAULT	(BMCR_ANENABLE | \
					 BMCR_FULLDPLX | \
					 BMCR_SPEED1000)

/* This is the same bit mask as the BMCR so re-use the BMCR default */
#define DP83869_FX_CTRL_DEFAULT	MII_DP83869_BMCR_DEFAULT

/* CFG1 bits */
#define DP83869_CFG1_DEFAULT	(ADVERTISE_1000HALF | \
				 ADVERTISE_1000FULL | \
				 CTL1000_AS_MASTER)

/* RGMIICTL bits */
#define DP83869_RGMII_TX_CLK_DELAY_EN		BIT(1)
#define DP83869_RGMII_RX_CLK_DELAY_EN		BIT(0)

/* STRAP_STS1 bits */
#define DP83869_STRAP_STS1_RESERVED		BIT(11)

/* PHYCTRL bits */
#define DP83869_RX_FIFO_SHIFT	12
#define DP83869_TX_FIFO_SHIFT	14

/* PHY_CTRL lower bytes 0x48 are declared as reserved */
#define DP83869_PHY_CTRL_DEFAULT	0x48
#define DP83869_PHYCR_FIFO_DEPTH_MASK	GENMASK(15, 12)
#define DP83869_PHYCR_RESERVED_MASK	BIT(11)

/* RGMIIDCTL bits */
#define DP83869_RGMII_TX_CLK_DELAY_SHIFT	4

/* IO_MUX_CFG bits */
#define DP83869_IO_MUX_CFG_IO_IMPEDANCE_CTRL	0x1f

#define DP83869_IO_MUX_CFG_IO_IMPEDANCE_MAX	0x0
#define DP83869_IO_MUX_CFG_IO_IMPEDANCE_MIN	0x1f
#define DP83869_IO_MUX_CFG_CLK_O_SEL_MASK	(0x1f << 8)
#define DP83869_IO_MUX_CFG_CLK_O_SEL_SHIFT	8

/* CFG3 bits */
#define DP83869_CFG3_PORT_MIRROR_EN              BIT(0)

/* CFG4 bits */
#define DP83869_INT_OE	BIT(7)

/* OP MODE */
#define DP83869_OP_MODE_MII			BIT(5)
#define DP83869_SGMII_RGMII_BRIDGE		BIT(6)

enum {
	DP83869_PORT_MIRRORING_KEEP,
	DP83869_PORT_MIRRORING_EN,
	DP83869_PORT_MIRRORING_DIS,
};

struct dp83869_private {
	int tx_fifo_depth;
	int rx_fifo_depth;
	int io_impedance;
	int port_mirroring;
	bool rxctrl_strap_quirk;
	int clk_output_sel;
	int mode;
};

static int dp83869_ack_interrupt(struct phy_device *phydev)
{
	int err = phy_read(phydev, MII_DP83869_ISR);

	if (err < 0)
		return err;

	return 0;
}

static int dp83869_config_intr(struct phy_device *phydev)
{
	int micr_status = 0;

	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
		micr_status = phy_read(phydev, MII_DP83869_MICR);
		if (micr_status < 0)
			return micr_status;

		micr_status |=
			(MII_DP83869_MICR_AN_ERR_INT_EN |
			MII_DP83869_MICR_SPEED_CHNG_INT_EN |
			MII_DP83869_MICR_AUTONEG_COMP_INT_EN |
			MII_DP83869_MICR_LINK_STS_CHNG_INT_EN |
			MII_DP83869_MICR_DUP_MODE_CHNG_INT_EN |
			MII_DP83869_MICR_SLEEP_MODE_CHNG_INT_EN);

		return phy_write(phydev, MII_DP83869_MICR, micr_status);
	}

	return phy_write(phydev, MII_DP83869_MICR, micr_status);
}

static int dp83869_config_port_mirroring(struct phy_device *phydev)
{
	struct dp83869_private *dp83869 = phydev->priv;

	if (dp83869->port_mirroring == DP83869_PORT_MIRRORING_EN)
		return phy_set_bits_mmd(phydev, DP83869_DEVADDR,
					DP83869_GEN_CFG3,
					DP83869_CFG3_PORT_MIRROR_EN);
	else
		return phy_clear_bits_mmd(phydev, DP83869_DEVADDR,
					  DP83869_GEN_CFG3,
					  DP83869_CFG3_PORT_MIRROR_EN);
}

#ifdef CONFIG_OF_MDIO
static int dp83869_of_init(struct phy_device *phydev)
{
	struct dp83869_private *dp83869 = phydev->priv;
	struct device *dev = &phydev->mdio.dev;
	struct device_node *of_node = dev->of_node;
	int ret;

	if (!of_node)
		return -ENODEV;

	dp83869->io_impedance = -EINVAL;

	/* Optional configuration */
	ret = of_property_read_u32(of_node, "ti,clk-output-sel",
				   &dp83869->clk_output_sel);
	if (ret || dp83869->clk_output_sel > DP83869_CLK_O_SEL_REF_CLK)
		dp83869->clk_output_sel = DP83869_CLK_O_SEL_REF_CLK;

	ret = of_property_read_u32(of_node, "ti,op-mode", &dp83869->mode);
	if (ret == 0) {
		if (dp83869->mode < DP83869_RGMII_COPPER_ETHERNET ||
		    dp83869->mode > DP83869_SGMII_COPPER_ETHERNET)
			return -EINVAL;
	}

	if (of_property_read_bool(of_node, "ti,max-output-impedance"))
		dp83869->io_impedance = DP83869_IO_MUX_CFG_IO_IMPEDANCE_MAX;
	else if (of_property_read_bool(of_node, "ti,min-output-impedance"))
		dp83869->io_impedance = DP83869_IO_MUX_CFG_IO_IMPEDANCE_MIN;

	if (of_property_read_bool(of_node, "enet-phy-lane-swap"))
		dp83869->port_mirroring = DP83869_PORT_MIRRORING_EN;
	else
		dp83869->port_mirroring = DP83869_PORT_MIRRORING_DIS;

	if (of_property_read_u32(of_node, "rx-fifo-depth",
				 &dp83869->rx_fifo_depth))
		dp83869->rx_fifo_depth = DP83869_PHYCR_FIFO_DEPTH_4_B_NIB;

	if (of_property_read_u32(of_node, "tx-fifo-depth",
				 &dp83869->tx_fifo_depth))
		dp83869->tx_fifo_depth = DP83869_PHYCR_FIFO_DEPTH_4_B_NIB;

	return ret;
}
#else
static int dp83869_of_init(struct phy_device *phydev)
{
	return 0;
}
#endif /* CONFIG_OF_MDIO */

static int dp83869_configure_rgmii(struct phy_device *phydev,
				   struct dp83869_private *dp83869)
{
	int ret = 0, val;

	if (phy_interface_is_rgmii(phydev)) {
		val = phy_read(phydev, MII_DP83869_PHYCTRL);
		if (val < 0)
			return val;

		val &= ~DP83869_PHYCR_FIFO_DEPTH_MASK;
		val |= (dp83869->tx_fifo_depth << DP83869_TX_FIFO_SHIFT);
		val |= (dp83869->rx_fifo_depth << DP83869_RX_FIFO_SHIFT);

		ret = phy_write(phydev, MII_DP83869_PHYCTRL, val);
		if (ret)
			return ret;
	}

	if (dp83869->io_impedance >= 0)
		ret = phy_modify_mmd(phydev, DP83869_DEVADDR,
				     DP83869_IO_MUX_CFG,
				     DP83869_IO_MUX_CFG_IO_IMPEDANCE_CTRL,
				     dp83869->io_impedance &
				     DP83869_IO_MUX_CFG_IO_IMPEDANCE_CTRL);

	return ret;
}

static int dp83869_configure_mode(struct phy_device *phydev,
				  struct dp83869_private *dp83869)
{
	int phy_ctrl_val;
	int ret;

	if (dp83869->mode < DP83869_RGMII_COPPER_ETHERNET ||
	    dp83869->mode > DP83869_SGMII_COPPER_ETHERNET)
		return -EINVAL;

	/* Below init sequence for each operational mode is defined in
	 * section 9.4.8 of the datasheet.
	 */
	ret = phy_write_mmd(phydev, DP83869_DEVADDR, DP83869_OP_MODE,
			    dp83869->mode);
	if (ret)
		return ret;

	ret = phy_write(phydev, MII_BMCR, MII_DP83869_BMCR_DEFAULT);
	if (ret)
		return ret;

	phy_ctrl_val = (dp83869->rx_fifo_depth << DP83869_RX_FIFO_SHIFT |
			dp83869->tx_fifo_depth << DP83869_TX_FIFO_SHIFT |
			DP83869_PHY_CTRL_DEFAULT);

	switch (dp83869->mode) {
	case DP83869_RGMII_COPPER_ETHERNET:
		ret = phy_write(phydev, MII_DP83869_PHYCTRL,
				phy_ctrl_val);
		if (ret)
			return ret;

		ret = phy_write(phydev, MII_CTRL1000, DP83869_CFG1_DEFAULT);
		if (ret)
			return ret;

		ret = dp83869_configure_rgmii(phydev, dp83869);
		if (ret)
			return ret;
		break;
	case DP83869_RGMII_SGMII_BRIDGE:
		ret = phy_modify_mmd(phydev, DP83869_DEVADDR, DP83869_OP_MODE,
				     DP83869_SGMII_RGMII_BRIDGE,
				     DP83869_SGMII_RGMII_BRIDGE);
		if (ret)
			return ret;

		ret = phy_write_mmd(phydev, DP83869_DEVADDR,
				    DP83869_FX_CTRL, DP83869_FX_CTRL_DEFAULT);
		if (ret)
			return ret;

		break;
	case DP83869_1000M_MEDIA_CONVERT:
		ret = phy_write(phydev, MII_DP83869_PHYCTRL,
				phy_ctrl_val);
		if (ret)
			return ret;

		ret = phy_write_mmd(phydev, DP83869_DEVADDR,
				    DP83869_FX_CTRL, DP83869_FX_CTRL_DEFAULT);
		if (ret)
			return ret;
		break;
	case DP83869_100M_MEDIA_CONVERT:
		ret = phy_write(phydev, MII_DP83869_PHYCTRL,
				phy_ctrl_val);
		if (ret)
			return ret;
		break;
	case DP83869_SGMII_COPPER_ETHERNET:
		ret = phy_write(phydev, MII_DP83869_PHYCTRL,
				phy_ctrl_val);
		if (ret)
			return ret;

		ret = phy_write(phydev, MII_CTRL1000, DP83869_CFG1_DEFAULT);
		if (ret)
			return ret;

		ret = phy_write_mmd(phydev, DP83869_DEVADDR,
				    DP83869_FX_CTRL, DP83869_FX_CTRL_DEFAULT);
		if (ret)
			return ret;

		break;
	case DP83869_RGMII_1000_BASE:
	case DP83869_RGMII_100_BASE:
		break;
	default:
		return -EINVAL;
	};

	return ret;
}

static int dp83869_config_init(struct phy_device *phydev)
{
	struct dp83869_private *dp83869 = phydev->priv;
	int ret, val;

	ret = dp83869_configure_mode(phydev, dp83869);
	if (ret)
		return ret;

	/* Enable Interrupt output INT_OE in CFG4 register */
	if (phy_interrupt_is_valid(phydev)) {
		val = phy_read(phydev, DP83869_CFG4);
		val |= DP83869_INT_OE;
		phy_write(phydev, DP83869_CFG4, val);
	}

	if (dp83869->port_mirroring != DP83869_PORT_MIRRORING_KEEP)
		dp83869_config_port_mirroring(phydev);

	/* Clock output selection if muxing property is set */
	if (dp83869->clk_output_sel != DP83869_CLK_O_SEL_REF_CLK)
		ret = phy_modify_mmd(phydev,
				     DP83869_DEVADDR, DP83869_IO_MUX_CFG,
				     DP83869_IO_MUX_CFG_CLK_O_SEL_MASK,
				     dp83869->clk_output_sel <<
				     DP83869_IO_MUX_CFG_CLK_O_SEL_SHIFT);

	return ret;
}

static int dp83869_probe(struct phy_device *phydev)
{
	struct dp83869_private *dp83869;
	int ret;

	dp83869 = devm_kzalloc(&phydev->mdio.dev, sizeof(*dp83869),
			       GFP_KERNEL);
	if (!dp83869)
		return -ENOMEM;

	phydev->priv = dp83869;

	ret = dp83869_of_init(phydev);
	if (ret)
		return ret;

	return dp83869_config_init(phydev);
}

static int dp83869_phy_reset(struct phy_device *phydev)
{
	int ret;

	ret = phy_write(phydev, DP83869_CTRL, DP83869_SW_RESET);
	if (ret < 0)
		return ret;

	usleep_range(10, 20);

	/* Global sw reset sets all registers to default.
	 * Need to set the registers in the PHY to the right config.
	 */
	return dp83869_config_init(phydev);
}

static struct phy_driver dp83869_driver[] = {
	{
		PHY_ID_MATCH_MODEL(DP83869_PHY_ID),
		.name		= "TI DP83869",

		.probe          = dp83869_probe,
		.config_init	= dp83869_config_init,
		.soft_reset	= dp83869_phy_reset,

		/* IRQ related */
		.ack_interrupt	= dp83869_ack_interrupt,
		.config_intr	= dp83869_config_intr,

		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
	},
};
module_phy_driver(dp83869_driver);

static struct mdio_device_id __maybe_unused dp83869_tbl[] = {
	{ PHY_ID_MATCH_MODEL(DP83869_PHY_ID) },
	{ }
};
MODULE_DEVICE_TABLE(mdio, dp83869_tbl);

MODULE_DESCRIPTION("Texas Instruments DP83869 PHY driver");
MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com");
MODULE_LICENSE("GPL v2");