/*
 * Copyright (C) 2016 Broadcom
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#define pr_fmt(fmt)             KBUILD_MODNAME ": " fmt

#include <linux/bcma/bcma.h>
#include <linux/brcmphy.h>
#include <linux/etherdevice.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include "bgmac.h"

#define NICPM_PADRING_CFG               0x00000004
#define NICPM_IOMUX_CTRL                0x00000008

#define NICPM_PADRING_CFG_INIT_VAL      0x74000000
#define NICPM_IOMUX_CTRL_INIT_VAL_AX    0x21880000

#define NICPM_IOMUX_CTRL_INIT_VAL       0x3196e000
#define NICPM_IOMUX_CTRL_SPD_SHIFT      10
#define NICPM_IOMUX_CTRL_SPD_10M        0
#define NICPM_IOMUX_CTRL_SPD_100M       1
#define NICPM_IOMUX_CTRL_SPD_1000M      2

static u32 platform_bgmac_read(struct bgmac *bgmac, u16 offset)
{
        return readl(bgmac->plat.base + offset);
}

static void platform_bgmac_write(struct bgmac *bgmac, u16 offset, u32 value)
{
        writel(value, bgmac->plat.base + offset);
}

static u32 platform_bgmac_idm_read(struct bgmac *bgmac, u16 offset)
{
        return readl(bgmac->plat.idm_base + offset);
}

static void platform_bgmac_idm_write(struct bgmac *bgmac, u16 offset, u32 value)
{
        writel(value, bgmac->plat.idm_base + offset);
}

static bool platform_bgmac_clk_enabled(struct bgmac *bgmac)
{
        if (!bgmac->plat.idm_base)
                return true;

        if ((bgmac_idm_read(bgmac, BCMA_IOCTL) & BGMAC_CLK_EN) != BGMAC_CLK_EN)
                return false;
        if (bgmac_idm_read(bgmac, BCMA_RESET_CTL) & BCMA_RESET_CTL_RESET)
                return false;
        return true;
}

static void platform_bgmac_clk_enable(struct bgmac *bgmac, u32 flags)
{
        u32 val;

        if (!bgmac->plat.idm_base)
                return;

        /* The Reset Control register only contains a single bit to show if the
         * controller is currently in reset.  Do a sanity check here, just in
         * case the bootloader happened to leave the device in reset.
         */
        val = bgmac_idm_read(bgmac, BCMA_RESET_CTL);
        if (val) {
                bgmac_idm_write(bgmac, BCMA_RESET_CTL, 0);
                bgmac_idm_read(bgmac, BCMA_RESET_CTL);
                udelay(1);
        }

        val = bgmac_idm_read(bgmac, BCMA_IOCTL);
        /* Some bits of BCMA_IOCTL set by HW/ATF and should not change */
        val |= flags & ~(BGMAC_AWCACHE | BGMAC_ARCACHE | BGMAC_AWUSER |
                         BGMAC_ARUSER);
        val |= BGMAC_CLK_EN;
        bgmac_idm_write(bgmac, BCMA_IOCTL, val);
        bgmac_idm_read(bgmac, BCMA_IOCTL);
        udelay(1);
}

static void platform_bgmac_cco_ctl_maskset(struct bgmac *bgmac, u32 offset,
                                           u32 mask, u32 set)
{
        /* This shouldn't be encountered */
        WARN_ON(1);
}

static u32 platform_bgmac_get_bus_clock(struct bgmac *bgmac)
{
        /* This shouldn't be encountered */
        WARN_ON(1);

        return 0;
}

static void platform_bgmac_cmn_maskset32(struct bgmac *bgmac, u16 offset,
                                         u32 mask, u32 set)
{
        /* This shouldn't be encountered */
        WARN_ON(1);
}

static void bgmac_nicpm_speed_set(struct net_device *net_dev)
{
        struct bgmac *bgmac = netdev_priv(net_dev);
        u32 val;

        if (!bgmac->plat.nicpm_base)
                return;

        /* SET RGMII IO CONFIG */
        writel(NICPM_PADRING_CFG_INIT_VAL,
               bgmac->plat.nicpm_base + NICPM_PADRING_CFG);

        val = NICPM_IOMUX_CTRL_INIT_VAL;
        switch (bgmac->net_dev->phydev->speed) {
        default:
                netdev_err(net_dev, "Unsupported speed. Defaulting to 1000Mb\n");
                fallthrough;
        case SPEED_1000:
                val |= NICPM_IOMUX_CTRL_SPD_1000M << NICPM_IOMUX_CTRL_SPD_SHIFT;
                break;
        case SPEED_100:
                val |= NICPM_IOMUX_CTRL_SPD_100M << NICPM_IOMUX_CTRL_SPD_SHIFT;
                break;
        case SPEED_10:
                val |= NICPM_IOMUX_CTRL_SPD_10M << NICPM_IOMUX_CTRL_SPD_SHIFT;
                break;
        }

        writel(val, bgmac->plat.nicpm_base + NICPM_IOMUX_CTRL);

        bgmac_adjust_link(bgmac->net_dev);
}

static int platform_phy_connect(struct bgmac *bgmac)
{
        struct phy_device *phy_dev;

        if (bgmac->plat.nicpm_base)
                phy_dev = of_phy_get_and_connect(bgmac->net_dev,
                                                 bgmac->dev->of_node,
                                                 bgmac_nicpm_speed_set);
        else
                phy_dev = of_phy_get_and_connect(bgmac->net_dev,
                                                 bgmac->dev->of_node,
                                                 bgmac_adjust_link);
        if (!phy_dev) {
                dev_err(bgmac->dev, "PHY connection failed\n");
                return -ENODEV;
        }

        return 0;
}

static int bgmac_probe(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        struct device_node *phy_node;
        struct bgmac *bgmac;
        struct resource *regs;
        int ret;

        bgmac = bgmac_alloc(&pdev->dev);
        if (!bgmac)
                return -ENOMEM;

        platform_set_drvdata(pdev, bgmac);

        /* Set the features of the 4707 family */
        bgmac->feature_flags |= BGMAC_FEAT_CLKCTLST;
        bgmac->feature_flags |= BGMAC_FEAT_NO_RESET;
        bgmac->feature_flags |= BGMAC_FEAT_CMDCFG_SR_REV4;
        bgmac->feature_flags |= BGMAC_FEAT_TX_MASK_SETUP;
        bgmac->feature_flags |= BGMAC_FEAT_RX_MASK_SETUP;
        bgmac->feature_flags |= BGMAC_FEAT_IDM_MASK;

        bgmac->dev = &pdev->dev;
        bgmac->dma_dev = &pdev->dev;

        ret = of_get_ethdev_address(np, bgmac->net_dev);
        if (ret == -EPROBE_DEFER)
                return ret;

        if (ret)
                dev_warn(&pdev->dev,
                         "MAC address not present in device tree\n");

        bgmac->irq = platform_get_irq(pdev, 0);
        if (bgmac->irq < 0)
                return bgmac->irq;

        bgmac->plat.base =
                devm_platform_ioremap_resource_byname(pdev, "amac_base");
        if (IS_ERR(bgmac->plat.base))
                return PTR_ERR(bgmac->plat.base);

        /* The idm_base resource is optional for some platforms */
        regs = platform_get_resource_byname(pdev, IORESOURCE_MEM, "idm_base");
        if (regs) {
                bgmac->plat.idm_base = devm_ioremap_resource(&pdev->dev, regs);
                if (IS_ERR(bgmac->plat.idm_base))
                        return PTR_ERR(bgmac->plat.idm_base);
                bgmac->feature_flags &= ~BGMAC_FEAT_IDM_MASK;
        }

        /* The nicpm_base resource is optional for some platforms */
        regs = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nicpm_base");
        if (regs) {
                bgmac->plat.nicpm_base = devm_ioremap_resource(&pdev->dev,
                                                               regs);
                if (IS_ERR(bgmac->plat.nicpm_base))
                        return PTR_ERR(bgmac->plat.nicpm_base);
        }

        bgmac->read = platform_bgmac_read;
        bgmac->write = platform_bgmac_write;
        bgmac->idm_read = platform_bgmac_idm_read;
        bgmac->idm_write = platform_bgmac_idm_write;
        bgmac->clk_enabled = platform_bgmac_clk_enabled;
        bgmac->clk_enable = platform_bgmac_clk_enable;
        bgmac->cco_ctl_maskset = platform_bgmac_cco_ctl_maskset;
        bgmac->get_bus_clock = platform_bgmac_get_bus_clock;
        bgmac->cmn_maskset32 = platform_bgmac_cmn_maskset32;
        phy_node = of_parse_phandle(np, "phy-handle", 0);
        if (phy_node) {
                of_node_put(phy_node);
                bgmac->phy_connect = platform_phy_connect;
        } else {
                bgmac->phy_connect = bgmac_phy_connect_direct;
                bgmac->feature_flags |= BGMAC_FEAT_FORCE_SPEED_2500;
        }

        return bgmac_enet_probe(bgmac);
}

static void bgmac_remove(struct platform_device *pdev)
{
        struct bgmac *bgmac = platform_get_drvdata(pdev);

        bgmac_enet_remove(bgmac);
}

#ifdef CONFIG_PM
static int bgmac_suspend(struct device *dev)
{
        struct bgmac *bgmac = dev_get_drvdata(dev);

        return bgmac_enet_suspend(bgmac);
}

static int bgmac_resume(struct device *dev)
{
        struct bgmac *bgmac = dev_get_drvdata(dev);

        return bgmac_enet_resume(bgmac);
}

static const struct dev_pm_ops bgmac_pm_ops = {
        .suspend = bgmac_suspend,
        .resume = bgmac_resume
};

#define BGMAC_PM_OPS (&bgmac_pm_ops)
#else
#define BGMAC_PM_OPS NULL
#endif /* CONFIG_PM */

static const struct of_device_id bgmac_of_enet_match[] = {
        {.compatible = "brcm,amac",},
        {.compatible = "brcm,nsp-amac",},
        {.compatible = "brcm,ns2-amac",},
        {},
};

MODULE_DEVICE_TABLE(of, bgmac_of_enet_match);

static struct platform_driver bgmac_enet_driver = {
        .driver = {
                .name  = "bgmac-enet",
                .of_match_table = bgmac_of_enet_match,
                .pm = BGMAC_PM_OPS
        },
        .probe = bgmac_probe,
        .remove = bgmac_remove,
};

module_platform_driver(bgmac_enet_driver);
MODULE_DESCRIPTION("Broadcom iProc GBit platform interface driver");
MODULE_LICENSE("GPL");