// SPDX-License-Identifier: GPL-2.0-only
/*
 * Broadcom GENET (Gigabit Ethernet) Wake-on-LAN support
 *
 * Copyright (c) 2014-2025 Broadcom
 */

#define pr_fmt(fmt)                             "bcmgenet_wol: " fmt

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <net/arp.h>

#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/phy.h>

#include "bcmgenet.h"

/* ethtool function - get WOL (Wake on LAN) settings, Only Magic Packet
 * Detection is supported through ethtool
 */
void bcmgenet_get_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
{
        struct bcmgenet_priv *priv = netdev_priv(dev);
        struct device *kdev = &priv->pdev->dev;
        u32 phy_wolopts = 0;

        if (dev->phydev) {
                phy_ethtool_get_wol(dev->phydev, wol);
                phy_wolopts = wol->wolopts;
        }

        /* MAC is not wake-up capable, return what the PHY does */
        if (!device_can_wakeup(kdev))
                return;

        /* Overlay MAC capabilities with that of the PHY queried before */
        wol->supported |= WAKE_MAGIC | WAKE_MAGICSECURE | WAKE_FILTER;
        wol->wolopts |= priv->wolopts;

        /* Return the PHY configured magic password */
        if (phy_wolopts & WAKE_MAGICSECURE)
                return;

        /* Otherwise the MAC one */
        memset(wol->sopass, 0, sizeof(wol->sopass));
        if (wol->wolopts & WAKE_MAGICSECURE)
                memcpy(wol->sopass, priv->sopass, sizeof(priv->sopass));
}

/* ethtool function - set WOL (Wake on LAN) settings.
 * Only for magic packet detection mode.
 */
int bcmgenet_set_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
{
        struct bcmgenet_priv *priv = netdev_priv(dev);
        struct device *kdev = &priv->pdev->dev;
        int ret;

        /* Try Wake-on-LAN from the PHY first */
        if (dev->phydev) {
                ret = phy_ethtool_set_wol(dev->phydev, wol);
                if (ret != -EOPNOTSUPP && wol->wolopts)
                        return ret;
        }

        if (!device_can_wakeup(kdev))
                return -ENOTSUPP;

        if (wol->wolopts & ~(WAKE_MAGIC | WAKE_MAGICSECURE | WAKE_FILTER))
                return -EINVAL;

        if (wol->wolopts & WAKE_MAGICSECURE)
                memcpy(priv->sopass, wol->sopass, sizeof(priv->sopass));

        /* Flag the device and relevant IRQ as wakeup capable */
        if (wol->wolopts) {
                device_set_wakeup_enable(kdev, 1);
                /* Avoid unbalanced enable_irq_wake calls */
                if (priv->wol_irq_disabled) {
                        enable_irq_wake(priv->wol_irq);
                        enable_irq_wake(priv->irq0);
                }
                priv->wol_irq_disabled = false;
        } else {
                device_set_wakeup_enable(kdev, 0);
                /* Avoid unbalanced disable_irq_wake calls */
                if (!priv->wol_irq_disabled) {
                        disable_irq_wake(priv->wol_irq);
                        disable_irq_wake(priv->irq0);
                }
                priv->wol_irq_disabled = true;
        }

        priv->wolopts = wol->wolopts;

        return 0;
}

static int bcmgenet_poll_wol_status(struct bcmgenet_priv *priv)
{
        struct net_device *dev = priv->dev;
        int retries = 0;

        while (!(bcmgenet_rbuf_readl(priv, RBUF_STATUS)
                & RBUF_STATUS_WOL)) {
                retries++;
                if (retries > 50) {
                        netdev_crit(dev, "polling wol mode timeout\n");
                        return -ETIMEDOUT;
                }
                mdelay(1);
        }

        return retries;
}

static void bcmgenet_set_mpd_password(struct bcmgenet_priv *priv)
{
        bcmgenet_umac_writel(priv, get_unaligned_be16(&priv->sopass[0]),
                             UMAC_MPD_PW_MS);
        bcmgenet_umac_writel(priv, get_unaligned_be32(&priv->sopass[2]),
                             UMAC_MPD_PW_LS);
}

int bcmgenet_wol_power_down_cfg(struct bcmgenet_priv *priv,
                                enum bcmgenet_power_mode mode)
{
        struct net_device *dev = priv->dev;
        u32 reg, hfb_ctrl_reg;
        int retries = 0;

        if (mode != GENET_POWER_WOL_MAGIC) {
                netif_err(priv, wol, dev, "unsupported mode: %d\n", mode);
                return -EINVAL;
        }

        if (priv->wolopts & (WAKE_MAGIC | WAKE_MAGICSECURE)) {
                reg = bcmgenet_umac_readl(priv, UMAC_MPD_CTRL);
                reg |= MPD_EN;
                if (priv->wolopts & WAKE_MAGICSECURE) {
                        bcmgenet_set_mpd_password(priv);
                        reg |= MPD_PW_EN;
                }
                bcmgenet_umac_writel(priv, reg, UMAC_MPD_CTRL);
        }

        hfb_ctrl_reg = bcmgenet_hfb_reg_readl(priv, HFB_CTRL);
        reg = hfb_ctrl_reg | RBUF_ACPI_EN;
        bcmgenet_hfb_reg_writel(priv, reg, HFB_CTRL);

        /* Do not leave UniMAC in MPD mode only */
        retries = bcmgenet_poll_wol_status(priv);
        if (retries < 0) {
                reg = bcmgenet_umac_readl(priv, UMAC_MPD_CTRL);
                reg &= ~(MPD_EN | MPD_PW_EN);
                bcmgenet_umac_writel(priv, reg, UMAC_MPD_CTRL);
                bcmgenet_hfb_reg_writel(priv, hfb_ctrl_reg, HFB_CTRL);
                return retries;
        }

        netif_dbg(priv, wol, dev, "MPD WOL-ready status set after %d msec\n",
                  retries);

        /* Disable phy status updates while suspending */
        mutex_lock(&dev->phydev->lock);
        dev->phydev->state = PHY_READY;
        mutex_unlock(&dev->phydev->lock);

        clk_prepare_enable(priv->clk_wol);

        /* Enable CRC forward */
        spin_lock_bh(&priv->reg_lock);
        reg = bcmgenet_umac_readl(priv, UMAC_CMD);
        priv->crc_fwd_en = 1;
        reg |= CMD_CRC_FWD;

        /* Can't suspend with WoL if MAC is still in reset */
        if (reg & CMD_SW_RESET)
                reg &= ~CMD_SW_RESET;

        /* Receiver must be enabled for WOL MP detection */
        reg |= CMD_RX_EN;
        bcmgenet_umac_writel(priv, reg, UMAC_CMD);
        spin_unlock_bh(&priv->reg_lock);

        reg = UMAC_IRQ_MPD_R;
        if (hfb_ctrl_reg & RBUF_HFB_EN)
                reg |=  UMAC_IRQ_HFB_SM | UMAC_IRQ_HFB_MM;

        bcmgenet_intrl2_0_writel(priv, reg, INTRL2_CPU_MASK_CLEAR);

        return 0;
}

int bcmgenet_wol_power_up_cfg(struct bcmgenet_priv *priv,
                              enum bcmgenet_power_mode mode)
{
        struct net_device *dev = priv->dev;
        u32 reg;

        if (mode != GENET_POWER_WOL_MAGIC) {
                netif_err(priv, wol, priv->dev, "invalid mode: %d\n", mode);
                return -EINVAL;
        }

        clk_disable_unprepare(priv->clk_wol);
        priv->crc_fwd_en = 0;

        bcmgenet_intrl2_0_writel(priv, UMAC_IRQ_WAKE_EVENT,
                                 INTRL2_CPU_MASK_SET);
        if (bcmgenet_has_mdio_intr(priv))
                bcmgenet_intrl2_0_writel(priv,
                                         UMAC_IRQ_MDIO_EVENT,
                                         INTRL2_CPU_MASK_CLEAR);

        /* Disable Magic Packet Detection */
        if (priv->wolopts & (WAKE_MAGIC | WAKE_MAGICSECURE)) {
                reg = bcmgenet_umac_readl(priv, UMAC_MPD_CTRL);
                if (!(reg & MPD_EN))
                        return -EPERM;  /* already reset so skip the rest */
                reg &= ~(MPD_EN | MPD_PW_EN);
                bcmgenet_umac_writel(priv, reg, UMAC_MPD_CTRL);
        }

        /* Disable ACPI mode */
        reg = bcmgenet_hfb_reg_readl(priv, HFB_CTRL);
        if (!(reg & RBUF_ACPI_EN))
                return -EPERM;  /* already reset so skip the rest */
        reg &= ~RBUF_ACPI_EN;
        bcmgenet_hfb_reg_writel(priv, reg, HFB_CTRL);

        /* Disable CRC Forward */
        spin_lock_bh(&priv->reg_lock);
        reg = bcmgenet_umac_readl(priv, UMAC_CMD);
        reg &= ~CMD_CRC_FWD;
        bcmgenet_umac_writel(priv, reg, UMAC_CMD);
        spin_unlock_bh(&priv->reg_lock);

        /* Resume link status tracking */
        mutex_lock(&dev->phydev->lock);
        if (dev->phydev->link)
                dev->phydev->state = PHY_RUNNING;
        else
                dev->phydev->state = PHY_NOLINK;
        mutex_unlock(&dev->phydev->lock);

        return 0;
}