// SPDX-License-Identifier: GPL-2.0+
/* drivers/net/phy/realtek.c
 *
 * Driver for Realtek PHYs
 *
 * Author: Johnson Leung <r58129@freescale.com>
 *
 * Copyright (c) 2004 Freescale Semiconductor, Inc.
 */
#include <linux/bitops.h>
#include <linux/phy.h>
#include <linux/module.h>
#include <linux/delay.h>

#define RTL821x_PHYSR				0x11
#define RTL821x_PHYSR_DUPLEX			BIT(13)
#define RTL821x_PHYSR_SPEED			GENMASK(15, 14)

#define RTL821x_INER				0x12
#define RTL8211B_INER_INIT			0x6400
#define RTL8211E_INER_LINK_STATUS		BIT(10)
#define RTL8211F_INER_LINK_STATUS		BIT(4)

#define RTL821x_INSR				0x13

#define RTL821x_EXT_PAGE_SELECT			0x1e
#define RTL821x_PAGE_SELECT			0x1f

#define RTL8211F_PHYCR1				0x18
#define RTL8211F_INSR				0x1d

#define RTL8211F_TX_DELAY			BIT(8)
#define RTL8211F_RX_DELAY			BIT(3)

#define RTL8211F_ALDPS_PLL_OFF			BIT(1)
#define RTL8211F_ALDPS_ENABLE			BIT(2)
#define RTL8211F_ALDPS_XTAL_OFF			BIT(12)

#define RTL8211E_CTRL_DELAY			BIT(13)
#define RTL8211E_TX_DELAY			BIT(12)
#define RTL8211E_RX_DELAY			BIT(11)

#define RTL8201F_ISR				0x1e
#define RTL8201F_IER				0x13

#define RTL8366RB_POWER_SAVE			0x15
#define RTL8366RB_POWER_SAVE_ON			BIT(12)

#define RTL_SUPPORTS_5000FULL			BIT(14)
#define RTL_SUPPORTS_2500FULL			BIT(13)
#define RTL_SUPPORTS_10000FULL			BIT(0)
#define RTL_ADV_2500FULL			BIT(7)
#define RTL_LPADV_10000FULL			BIT(11)
#define RTL_LPADV_5000FULL			BIT(6)
#define RTL_LPADV_2500FULL			BIT(5)

#define RTLGEN_SPEED_MASK			0x0630

#define RTL_GENERIC_PHYID			0x001cc800

MODULE_DESCRIPTION("Realtek PHY driver");
MODULE_AUTHOR("Johnson Leung");
MODULE_LICENSE("GPL");

static int rtl821x_read_page(struct phy_device *phydev)
{
	return __phy_read(phydev, RTL821x_PAGE_SELECT);
}

static int rtl821x_write_page(struct phy_device *phydev, int page)
{
	return __phy_write(phydev, RTL821x_PAGE_SELECT, page);
}

static int rtl8201_ack_interrupt(struct phy_device *phydev)
{
	int err;

	err = phy_read(phydev, RTL8201F_ISR);

	return (err < 0) ? err : 0;
}

static int rtl821x_ack_interrupt(struct phy_device *phydev)
{
	int err;

	err = phy_read(phydev, RTL821x_INSR);

	return (err < 0) ? err : 0;
}

static int rtl8211f_ack_interrupt(struct phy_device *phydev)
{
	int err;

	err = phy_read_paged(phydev, 0xa43, RTL8211F_INSR);

	return (err < 0) ? err : 0;
}

static int rtl8201_config_intr(struct phy_device *phydev)
{
	u16 val;

	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
		val = BIT(13) | BIT(12) | BIT(11);
	else
		val = 0;

	return phy_write_paged(phydev, 0x7, RTL8201F_IER, val);
}

static int rtl8211b_config_intr(struct phy_device *phydev)
{
	int err;

	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
		err = phy_write(phydev, RTL821x_INER,
				RTL8211B_INER_INIT);
	else
		err = phy_write(phydev, RTL821x_INER, 0);

	return err;
}

static int rtl8211e_config_intr(struct phy_device *phydev)
{
	int err;

	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
		err = phy_write(phydev, RTL821x_INER,
				RTL8211E_INER_LINK_STATUS);
	else
		err = phy_write(phydev, RTL821x_INER, 0);

	return err;
}

static int rtl8211f_config_intr(struct phy_device *phydev)
{
	u16 val;

	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
		val = RTL8211F_INER_LINK_STATUS;
	else
		val = 0;

	return phy_write_paged(phydev, 0xa42, RTL821x_INER, val);
}

static int rtl8211_config_aneg(struct phy_device *phydev)
{
	int ret;

	ret = genphy_config_aneg(phydev);
	if (ret < 0)
		return ret;

	/* Quirk was copied from vendor driver. Unfortunately it includes no
	 * description of the magic numbers.
	 */
	if (phydev->speed == SPEED_100 && phydev->autoneg == AUTONEG_DISABLE) {
		phy_write(phydev, 0x17, 0x2138);
		phy_write(phydev, 0x0e, 0x0260);
	} else {
		phy_write(phydev, 0x17, 0x2108);
		phy_write(phydev, 0x0e, 0x0000);
	}

	return 0;
}

static int rtl8211c_config_init(struct phy_device *phydev)
{
	/* RTL8211C has an issue when operating in Gigabit slave mode */
	return phy_set_bits(phydev, MII_CTRL1000,
			    CTL1000_ENABLE_MASTER | CTL1000_AS_MASTER);
}

static int rtl8211f_config_init(struct phy_device *phydev)
{
	struct device *dev = &phydev->mdio.dev;
	u16 val_txdly, val_rxdly;
	u16 val;
	int ret;

	val = RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_XTAL_OFF;
	phy_modify_paged_changed(phydev, 0xa43, RTL8211F_PHYCR1, val, val);

	switch (phydev->interface) {
	case PHY_INTERFACE_MODE_RGMII:
		val_txdly = 0;
		val_rxdly = 0;
		break;

	case PHY_INTERFACE_MODE_RGMII_RXID:
		val_txdly = 0;
		val_rxdly = RTL8211F_RX_DELAY;
		break;

	case PHY_INTERFACE_MODE_RGMII_TXID:
		val_txdly = RTL8211F_TX_DELAY;
		val_rxdly = 0;
		break;

	case PHY_INTERFACE_MODE_RGMII_ID:
		val_txdly = RTL8211F_TX_DELAY;
		val_rxdly = RTL8211F_RX_DELAY;
		break;

	default: /* the rest of the modes imply leaving delay as is. */
		return 0;
	}

	ret = phy_modify_paged_changed(phydev, 0xd08, 0x11, RTL8211F_TX_DELAY,
				       val_txdly);
	if (ret < 0) {
		dev_err(dev, "Failed to update the TX delay register\n");
		return ret;
	} else if (ret) {
		dev_dbg(dev,
			"%s 2ns TX delay (and changing the value from pin-strapping RXD1 or the bootloader)\n",
			val_txdly ? "Enabling" : "Disabling");
	} else {
		dev_dbg(dev,
			"2ns TX delay was already %s (by pin-strapping RXD1 or bootloader configuration)\n",
			val_txdly ? "enabled" : "disabled");
	}

	ret = phy_modify_paged_changed(phydev, 0xd08, 0x15, RTL8211F_RX_DELAY,
				       val_rxdly);
	if (ret < 0) {
		dev_err(dev, "Failed to update the RX delay register\n");
		return ret;
	} else if (ret) {
		dev_dbg(dev,
			"%s 2ns RX delay (and changing the value from pin-strapping RXD0 or the bootloader)\n",
			val_rxdly ? "Enabling" : "Disabling");
	} else {
		dev_dbg(dev,
			"2ns RX delay was already %s (by pin-strapping RXD0 or bootloader configuration)\n",
			val_rxdly ? "enabled" : "disabled");
	}

	return 0;
}

static int rtl8211e_config_init(struct phy_device *phydev)
{
	int ret = 0, oldpage;
	u16 val;

	/* enable TX/RX delay for rgmii-* modes, and disable them for rgmii. */
	switch (phydev->interface) {
	case PHY_INTERFACE_MODE_RGMII:
		val = RTL8211E_CTRL_DELAY | 0;
		break;
	case PHY_INTERFACE_MODE_RGMII_ID:
		val = RTL8211E_CTRL_DELAY | RTL8211E_TX_DELAY | RTL8211E_RX_DELAY;
		break;
	case PHY_INTERFACE_MODE_RGMII_RXID:
		val = RTL8211E_CTRL_DELAY | RTL8211E_RX_DELAY;
		break;
	case PHY_INTERFACE_MODE_RGMII_TXID:
		val = RTL8211E_CTRL_DELAY | RTL8211E_TX_DELAY;
		break;
	default: /* the rest of the modes imply leaving delays as is. */
		return 0;
	}

	/* According to a sample driver there is a 0x1c config register on the
	 * 0xa4 extension page (0x7) layout. It can be used to disable/enable
	 * the RX/TX delays otherwise controlled by RXDLY/TXDLY pins.
	 * The configuration register definition:
	 * 14 = reserved
	 * 13 = Force Tx RX Delay controlled by bit12 bit11,
	 * 12 = RX Delay, 11 = TX Delay
	 * 10:0 = Test && debug settings reserved by realtek
	 */
	oldpage = phy_select_page(phydev, 0x7);
	if (oldpage < 0)
		goto err_restore_page;

	ret = __phy_write(phydev, RTL821x_EXT_PAGE_SELECT, 0xa4);
	if (ret)
		goto err_restore_page;

	ret = __phy_modify(phydev, 0x1c, RTL8211E_CTRL_DELAY
			   | RTL8211E_TX_DELAY | RTL8211E_RX_DELAY,
			   val);

err_restore_page:
	return phy_restore_page(phydev, oldpage, ret);
}

static int rtl8211b_suspend(struct phy_device *phydev)
{
	phy_write(phydev, MII_MMD_DATA, BIT(9));

	return genphy_suspend(phydev);
}

static int rtl8211b_resume(struct phy_device *phydev)
{
	phy_write(phydev, MII_MMD_DATA, 0);

	return genphy_resume(phydev);
}

static int rtl8366rb_config_init(struct phy_device *phydev)
{
	int ret;

	ret = phy_set_bits(phydev, RTL8366RB_POWER_SAVE,
			   RTL8366RB_POWER_SAVE_ON);
	if (ret) {
		dev_err(&phydev->mdio.dev,
			"error enabling power management\n");
	}

	return ret;
}

/* get actual speed to cover the downshift case */
static int rtlgen_get_speed(struct phy_device *phydev)
{
	int val;

	if (!phydev->link)
		return 0;

	val = phy_read_paged(phydev, 0xa43, 0x12);
	if (val < 0)
		return val;

	switch (val & RTLGEN_SPEED_MASK) {
	case 0x0000:
		phydev->speed = SPEED_10;
		break;
	case 0x0010:
		phydev->speed = SPEED_100;
		break;
	case 0x0020:
		phydev->speed = SPEED_1000;
		break;
	case 0x0200:
		phydev->speed = SPEED_10000;
		break;
	case 0x0210:
		phydev->speed = SPEED_2500;
		break;
	case 0x0220:
		phydev->speed = SPEED_5000;
		break;
	default:
		break;
	}

	return 0;
}

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

	ret = genphy_read_status(phydev);
	if (ret < 0)
		return ret;

	return rtlgen_get_speed(phydev);
}

static int rtlgen_read_mmd(struct phy_device *phydev, int devnum, u16 regnum)
{
	int ret;

	if (devnum == MDIO_MMD_PCS && regnum == MDIO_PCS_EEE_ABLE) {
		rtl821x_write_page(phydev, 0xa5c);
		ret = __phy_read(phydev, 0x12);
		rtl821x_write_page(phydev, 0);
	} else if (devnum == MDIO_MMD_AN && regnum == MDIO_AN_EEE_ADV) {
		rtl821x_write_page(phydev, 0xa5d);
		ret = __phy_read(phydev, 0x10);
		rtl821x_write_page(phydev, 0);
	} else if (devnum == MDIO_MMD_AN && regnum == MDIO_AN_EEE_LPABLE) {
		rtl821x_write_page(phydev, 0xa5d);
		ret = __phy_read(phydev, 0x11);
		rtl821x_write_page(phydev, 0);
	} else {
		ret = -EOPNOTSUPP;
	}

	return ret;
}

static int rtlgen_write_mmd(struct phy_device *phydev, int devnum, u16 regnum,
			    u16 val)
{
	int ret;

	if (devnum == MDIO_MMD_AN && regnum == MDIO_AN_EEE_ADV) {
		rtl821x_write_page(phydev, 0xa5d);
		ret = __phy_write(phydev, 0x10, val);
		rtl821x_write_page(phydev, 0);
	} else {
		ret = -EOPNOTSUPP;
	}

	return ret;
}

static int rtl822x_read_mmd(struct phy_device *phydev, int devnum, u16 regnum)
{
	int ret = rtlgen_read_mmd(phydev, devnum, regnum);

	if (ret != -EOPNOTSUPP)
		return ret;

	if (devnum == MDIO_MMD_PCS && regnum == MDIO_PCS_EEE_ABLE2) {
		rtl821x_write_page(phydev, 0xa6e);
		ret = __phy_read(phydev, 0x16);
		rtl821x_write_page(phydev, 0);
	} else if (devnum == MDIO_MMD_AN && regnum == MDIO_AN_EEE_ADV2) {
		rtl821x_write_page(phydev, 0xa6d);
		ret = __phy_read(phydev, 0x12);
		rtl821x_write_page(phydev, 0);
	} else if (devnum == MDIO_MMD_AN && regnum == MDIO_AN_EEE_LPABLE2) {
		rtl821x_write_page(phydev, 0xa6d);
		ret = __phy_read(phydev, 0x10);
		rtl821x_write_page(phydev, 0);
	}

	return ret;
}

static int rtl822x_write_mmd(struct phy_device *phydev, int devnum, u16 regnum,
			     u16 val)
{
	int ret = rtlgen_write_mmd(phydev, devnum, regnum, val);

	if (ret != -EOPNOTSUPP)
		return ret;

	if (devnum == MDIO_MMD_AN && regnum == MDIO_AN_EEE_ADV2) {
		rtl821x_write_page(phydev, 0xa6d);
		ret = __phy_write(phydev, 0x12, val);
		rtl821x_write_page(phydev, 0);
	}

	return ret;
}

static int rtl822x_get_features(struct phy_device *phydev)
{
	int val;

	val = phy_read_paged(phydev, 0xa61, 0x13);
	if (val < 0)
		return val;

	linkmode_mod_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
			 phydev->supported, val & RTL_SUPPORTS_2500FULL);
	linkmode_mod_bit(ETHTOOL_LINK_MODE_5000baseT_Full_BIT,
			 phydev->supported, val & RTL_SUPPORTS_5000FULL);
	linkmode_mod_bit(ETHTOOL_LINK_MODE_10000baseT_Full_BIT,
			 phydev->supported, val & RTL_SUPPORTS_10000FULL);

	return genphy_read_abilities(phydev);
}

static int rtl822x_config_aneg(struct phy_device *phydev)
{
	int ret = 0;

	if (phydev->autoneg == AUTONEG_ENABLE) {
		u16 adv2500 = 0;

		if (linkmode_test_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
				      phydev->advertising))
			adv2500 = RTL_ADV_2500FULL;

		ret = phy_modify_paged_changed(phydev, 0xa5d, 0x12,
					       RTL_ADV_2500FULL, adv2500);
		if (ret < 0)
			return ret;
	}

	return __genphy_config_aneg(phydev, ret);
}

static int rtl822x_read_status(struct phy_device *phydev)
{
	int ret;

	if (phydev->autoneg == AUTONEG_ENABLE) {
		int lpadv = phy_read_paged(phydev, 0xa5d, 0x13);

		if (lpadv < 0)
			return lpadv;

		linkmode_mod_bit(ETHTOOL_LINK_MODE_10000baseT_Full_BIT,
			phydev->lp_advertising, lpadv & RTL_LPADV_10000FULL);
		linkmode_mod_bit(ETHTOOL_LINK_MODE_5000baseT_Full_BIT,
			phydev->lp_advertising, lpadv & RTL_LPADV_5000FULL);
		linkmode_mod_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
			phydev->lp_advertising, lpadv & RTL_LPADV_2500FULL);
	}

	ret = genphy_read_status(phydev);
	if (ret < 0)
		return ret;

	return rtlgen_get_speed(phydev);
}

static bool rtlgen_supports_2_5gbps(struct phy_device *phydev)
{
	int val;

	phy_write(phydev, RTL821x_PAGE_SELECT, 0xa61);
	val = phy_read(phydev, 0x13);
	phy_write(phydev, RTL821x_PAGE_SELECT, 0);

	return val >= 0 && val & RTL_SUPPORTS_2500FULL;
}

static int rtlgen_match_phy_device(struct phy_device *phydev)
{
	return phydev->phy_id == RTL_GENERIC_PHYID &&
	       !rtlgen_supports_2_5gbps(phydev);
}

static int rtl8226_match_phy_device(struct phy_device *phydev)
{
	return phydev->phy_id == RTL_GENERIC_PHYID &&
	       rtlgen_supports_2_5gbps(phydev);
}

static int rtlgen_resume(struct phy_device *phydev)
{
	int ret = genphy_resume(phydev);

	/* Internal PHY's from RTL8168h up may not be instantly ready */
	msleep(20);

	return ret;
}

static struct phy_driver realtek_drvs[] = {
	{
		PHY_ID_MATCH_EXACT(0x00008201),
		.name           = "RTL8201CP Ethernet",
	}, {
		PHY_ID_MATCH_EXACT(0x001cc816),
		.name		= "RTL8201F Fast Ethernet",
		.ack_interrupt	= &rtl8201_ack_interrupt,
		.config_intr	= &rtl8201_config_intr,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		PHY_ID_MATCH_MODEL(0x001cc880),
		.name		= "RTL8208 Fast Ethernet",
		.read_mmd	= genphy_read_mmd_unsupported,
		.write_mmd	= genphy_write_mmd_unsupported,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc910),
		.name		= "RTL8211 Gigabit Ethernet",
		.config_aneg	= rtl8211_config_aneg,
		.read_mmd	= &genphy_read_mmd_unsupported,
		.write_mmd	= &genphy_write_mmd_unsupported,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc912),
		.name		= "RTL8211B Gigabit Ethernet",
		.ack_interrupt	= &rtl821x_ack_interrupt,
		.config_intr	= &rtl8211b_config_intr,
		.read_mmd	= &genphy_read_mmd_unsupported,
		.write_mmd	= &genphy_write_mmd_unsupported,
		.suspend	= rtl8211b_suspend,
		.resume		= rtl8211b_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc913),
		.name		= "RTL8211C Gigabit Ethernet",
		.config_init	= rtl8211c_config_init,
		.read_mmd	= &genphy_read_mmd_unsupported,
		.write_mmd	= &genphy_write_mmd_unsupported,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc914),
		.name		= "RTL8211DN Gigabit Ethernet",
		.ack_interrupt	= rtl821x_ack_interrupt,
		.config_intr	= rtl8211e_config_intr,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc915),
		.name		= "RTL8211E Gigabit Ethernet",
		.config_init	= &rtl8211e_config_init,
		.ack_interrupt	= &rtl821x_ack_interrupt,
		.config_intr	= &rtl8211e_config_intr,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc916),
		.name		= "RTL8211F Gigabit Ethernet",
		.config_init	= &rtl8211f_config_init,
		.ack_interrupt	= &rtl8211f_ack_interrupt,
		.config_intr	= &rtl8211f_config_intr,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
	}, {
		.name		= "Generic FE-GE Realtek PHY",
		.match_phy_device = rtlgen_match_phy_device,
		.read_status	= rtlgen_read_status,
		.suspend	= genphy_suspend,
		.resume		= rtlgen_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
		.read_mmd	= rtlgen_read_mmd,
		.write_mmd	= rtlgen_write_mmd,
	}, {
		.name		= "RTL8226 2.5Gbps PHY",
		.match_phy_device = rtl8226_match_phy_device,
		.get_features	= rtl822x_get_features,
		.config_aneg	= rtl822x_config_aneg,
		.read_status	= rtl822x_read_status,
		.suspend	= genphy_suspend,
		.resume		= rtlgen_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
		.read_mmd	= rtl822x_read_mmd,
		.write_mmd	= rtl822x_write_mmd,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc840),
		.name		= "RTL8226B_RTL8221B 2.5Gbps PHY",
		.get_features	= rtl822x_get_features,
		.config_aneg	= rtl822x_config_aneg,
		.read_status	= rtl822x_read_status,
		.suspend	= genphy_suspend,
		.resume		= rtlgen_resume,
		.read_page	= rtl821x_read_page,
		.write_page	= rtl821x_write_page,
		.read_mmd	= rtl822x_read_mmd,
		.write_mmd	= rtl822x_write_mmd,
	}, {
		PHY_ID_MATCH_EXACT(0x001cc961),
		.name		= "RTL8366RB Gigabit Ethernet",
		.config_init	= &rtl8366rb_config_init,
		/* These interrupts are handled by the irq controller
		 * embedded inside the RTL8366RB, they get unmasked when the
		 * irq is requested and ACKed by reading the status register,
		 * which is done by the irqchip code.
		 */
		.ack_interrupt	= genphy_no_ack_interrupt,
		.config_intr	= genphy_no_config_intr,
		.suspend	= genphy_suspend,
		.resume		= genphy_resume,
	},
};

module_phy_driver(realtek_drvs);

static const struct mdio_device_id __maybe_unused realtek_tbl[] = {
	{ PHY_ID_MATCH_VENDOR(0x001cc800) },
	{ }
};

MODULE_DEVICE_TABLE(mdio, realtek_tbl);