// SPDX-License-Identifier: GPL-2.0-only
/*
 * Freescale Ethernet controllers
 *
 * Copyright (c) 2005 Intracom S.A.
 *  by Pantelis Antoniou <panto@intracom.gr>
 *
 * 2005 (c) MontaVista Software, Inc.
 * Vitaly Bordug <vbordug@ru.mvista.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/crc32.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/ethtool.h>
#include <linux/bitops.h>
#include <linux/fs.h>
#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/gfp.h>

#include <asm/irq.h>
#include <linux/uaccess.h>

#include "fs_enet.h"
#include "fec.h"

/*************************************************/

#if defined(CONFIG_CPM1)
/* for a CPM1 __raw_xxx's are sufficient */
#define __fs_out32(addr, x)     __raw_writel(x, addr)
#define __fs_out16(addr, x)     __raw_writew(x, addr)
#define __fs_in32(addr) __raw_readl(addr)
#define __fs_in16(addr) __raw_readw(addr)
#else
/* for others play it safe */
#define __fs_out32(addr, x)     out_be32(addr, x)
#define __fs_out16(addr, x)     out_be16(addr, x)
#define __fs_in32(addr) in_be32(addr)
#define __fs_in16(addr) in_be16(addr)
#endif

/* write */
#define FW(_fecp, _reg, _v) __fs_out32(&(_fecp)->fec_ ## _reg, (_v))

/* read */
#define FR(_fecp, _reg) __fs_in32(&(_fecp)->fec_ ## _reg)

/* set bits */
#define FS(_fecp, _reg, _v) FW(_fecp, _reg, FR(_fecp, _reg) | (_v))

/* clear bits */
#define FC(_fecp, _reg, _v) FW(_fecp, _reg, FR(_fecp, _reg) & ~(_v))

/*
 * Delay to wait for FEC reset command to complete (in us)
 */
#define FEC_RESET_DELAY         50

static int whack_reset(struct fec __iomem *fecp)
{
        int i;

        FW(fecp, ecntrl, FEC_ECNTRL_PINMUX | FEC_ECNTRL_RESET);
        for (i = 0; i < FEC_RESET_DELAY; i++) {
                if ((FR(fecp, ecntrl) & FEC_ECNTRL_RESET) == 0)
                        return 0;       /* OK */
                udelay(1);
        }

        return -1;
}

static int do_pd_setup(struct fs_enet_private *fep)
{
        struct platform_device *ofdev = to_platform_device(fep->dev);

        fep->interrupt = irq_of_parse_and_map(ofdev->dev.of_node, 0);
        if (!fep->interrupt)
                return -EINVAL;

        fep->fec.fecp = of_iomap(ofdev->dev.of_node, 0);
        if (!fep->fec.fecp)
                return -EINVAL;

        return 0;
}

#define FEC_NAPI_EVENT_MSK      (FEC_ENET_RXF | FEC_ENET_RXB | FEC_ENET_TXF)
#define FEC_EVENT               (FEC_ENET_RXF | FEC_ENET_TXF)
#define FEC_ERR_EVENT_MSK       (FEC_ENET_HBERR | FEC_ENET_BABR | \
                                 FEC_ENET_BABT | FEC_ENET_EBERR)

static int setup_data(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);

        if (do_pd_setup(fep) != 0)
                return -EINVAL;

        fep->fec.hthi = 0;
        fep->fec.htlo = 0;

        fep->ev_napi = FEC_NAPI_EVENT_MSK;
        fep->ev = FEC_EVENT;
        fep->ev_err = FEC_ERR_EVENT_MSK;

        return 0;
}

static int allocate_bd(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        const struct fs_platform_info *fpi = fep->fpi;

        fep->ring_base = (void __force __iomem *)dma_alloc_coherent(fep->dev,
                                            (fpi->tx_ring + fpi->rx_ring) *
                                            sizeof(cbd_t), &fep->ring_mem_addr,
                                            GFP_KERNEL);
        if (fep->ring_base == NULL)
                return -ENOMEM;

        return 0;
}

static void free_bd(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        const struct fs_platform_info *fpi = fep->fpi;

        if(fep->ring_base)
                dma_free_coherent(fep->dev, (fpi->tx_ring + fpi->rx_ring)
                                        * sizeof(cbd_t),
                                        (void __force *)fep->ring_base,
                                        fep->ring_mem_addr);
}

static void cleanup_data(struct net_device *dev)
{
        /* nothing */
}

static void set_promiscuous_mode(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        FS(fecp, r_cntrl, FEC_RCNTRL_PROM);
}

static void set_multicast_start(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);

        fep->fec.hthi = 0;
        fep->fec.htlo = 0;
}

static void set_multicast_one(struct net_device *dev, const u8 *mac)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        int temp, hash_index;
        u32 crc, csrVal;

        crc = ether_crc(6, mac);

        temp = (crc & 0x3f) >> 1;
        hash_index = ((temp & 0x01) << 4) |
                     ((temp & 0x02) << 2) |
                     ((temp & 0x04)) |
                     ((temp & 0x08) >> 2) |
                     ((temp & 0x10) >> 4);
        csrVal = 1 << hash_index;
        if (crc & 1)
                fep->fec.hthi |= csrVal;
        else
                fep->fec.htlo |= csrVal;
}

static void set_multicast_finish(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        /* if all multi or too many multicasts; just enable all */
        if ((dev->flags & IFF_ALLMULTI) != 0 ||
            netdev_mc_count(dev) > FEC_MAX_MULTICAST_ADDRS) {
                fep->fec.hthi = 0xffffffffU;
                fep->fec.htlo = 0xffffffffU;
        }

        FC(fecp, r_cntrl, FEC_RCNTRL_PROM);
        FW(fecp, grp_hash_table_high, fep->fec.hthi);
        FW(fecp, grp_hash_table_low, fep->fec.htlo);
}

static void set_multicast_list(struct net_device *dev)
{
        struct netdev_hw_addr *ha;

        if ((dev->flags & IFF_PROMISC) == 0) {
                set_multicast_start(dev);
                netdev_for_each_mc_addr(ha, dev)
                        set_multicast_one(dev, ha->addr);
                set_multicast_finish(dev);
        } else
                set_promiscuous_mode(dev);
}

static void restart(struct net_device *dev, phy_interface_t interface,
                    int speed, int duplex)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;
        const struct fs_platform_info *fpi = fep->fpi;
        dma_addr_t rx_bd_base_phys, tx_bd_base_phys;
        int r;
        u32 addrhi, addrlo;

        struct mii_bus *mii = dev->phydev->mdio.bus;
        struct fec_info* fec_inf = mii->priv;

        r = whack_reset(fep->fec.fecp);
        if (r != 0)
                dev_err(fep->dev, "FEC Reset FAILED!\n");
        /*
         * Set station address.
         */
        addrhi = ((u32) dev->dev_addr[0] << 24) |
                 ((u32) dev->dev_addr[1] << 16) |
                 ((u32) dev->dev_addr[2] <<  8) |
                  (u32) dev->dev_addr[3];
        addrlo = ((u32) dev->dev_addr[4] << 24) |
                 ((u32) dev->dev_addr[5] << 16);
        FW(fecp, addr_low, addrhi);
        FW(fecp, addr_high, addrlo);

        /*
         * Reset all multicast.
         */
        FW(fecp, grp_hash_table_high, fep->fec.hthi);
        FW(fecp, grp_hash_table_low, fep->fec.htlo);

        /*
         * Set maximum receive buffer size.
         */
        FW(fecp, r_buff_size, PKT_MAXBLR_SIZE);
#ifdef CONFIG_FS_ENET_MPC5121_FEC
        FW(fecp, r_cntrl, PKT_MAXBUF_SIZE << 16);
#else
        FW(fecp, r_hash, PKT_MAXBUF_SIZE);
#endif

        /* get physical address */
        rx_bd_base_phys = fep->ring_mem_addr;
        tx_bd_base_phys = rx_bd_base_phys + sizeof(cbd_t) * fpi->rx_ring;

        /*
         * Set receive and transmit descriptor base.
         */
        FW(fecp, r_des_start, rx_bd_base_phys);
        FW(fecp, x_des_start, tx_bd_base_phys);

        fs_init_bds(dev);

        /*
         * Enable big endian and don't care about SDMA FC.
         */
#ifdef CONFIG_FS_ENET_MPC5121_FEC
        FS(fecp, dma_control, 0xC0000000);
#else
        FW(fecp, fun_code, 0x78000000);
#endif

        /*
         * Set MII speed.
         */
        FW(fecp, mii_speed, fec_inf->mii_speed);

        /*
         * Clear any outstanding interrupt.
         */
        FW(fecp, ievent, 0xffc0);
#ifndef CONFIG_FS_ENET_MPC5121_FEC
        FW(fecp, ivec, (virq_to_hw(fep->interrupt) / 2) << 29);

        FW(fecp, r_cntrl, FEC_RCNTRL_MII_MODE); /* MII enable */
#else
        /*
         * Only set MII/RMII mode - do not touch maximum frame length
         * configured before.
         */
        FS(fecp, r_cntrl, interface == PHY_INTERFACE_MODE_RMII ?
                          FEC_RCNTRL_RMII_MODE : FEC_RCNTRL_MII_MODE);
#endif
        /*
         * adjust to duplex mode
         */
        if (duplex == DUPLEX_FULL) {
                FC(fecp, r_cntrl, FEC_RCNTRL_DRT);
                FS(fecp, x_cntrl, FEC_TCNTRL_FDEN);     /* FD enable */
        } else {
                FS(fecp, r_cntrl, FEC_RCNTRL_DRT);
                FC(fecp, x_cntrl, FEC_TCNTRL_FDEN);     /* FD disable */
        }

        /* Restore multicast and promiscuous settings */
        set_multicast_list(dev);

        /*
         * Enable interrupts we wish to service.
         */
        FW(fecp, imask, FEC_ENET_TXF | FEC_ENET_TXB |
           FEC_ENET_RXF | FEC_ENET_RXB);

        /*
         * And last, enable the transmit and receive processing.
         */
        FW(fecp, ecntrl, FEC_ECNTRL_PINMUX | FEC_ECNTRL_ETHER_EN);
        FW(fecp, r_des_active, 0x01000000);
}

static void stop(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;
        int i;

        if ((FR(fecp, ecntrl) & FEC_ECNTRL_ETHER_EN) == 0)
                return;         /* already down */

        FW(fecp, x_cntrl, 0x01);        /* Graceful transmit stop */
        for (i = 0; ((FR(fecp, ievent) & 0x10000000) == 0) &&
             i < FEC_RESET_DELAY; i++)
                udelay(1);

        if (i == FEC_RESET_DELAY)
                dev_warn(fep->dev, "FEC timeout on graceful transmit stop\n");
        /*
         * Disable FEC. Let only MII interrupts.
         */
        FW(fecp, imask, 0);
        FC(fecp, ecntrl, FEC_ECNTRL_ETHER_EN);

        fs_cleanup_bds(dev);
}

static void napi_clear_event_fs(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        FW(fecp, ievent, FEC_NAPI_EVENT_MSK);
}

static void napi_enable_fs(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        FS(fecp, imask, FEC_NAPI_EVENT_MSK);
}

static void napi_disable_fs(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        FC(fecp, imask, FEC_NAPI_EVENT_MSK);
}

static void rx_bd_done(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        FW(fecp, r_des_active, 0x01000000);
}

static void tx_kickstart(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        FW(fecp, x_des_active, 0x01000000);
}

static u32 get_int_events(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        return FR(fecp, ievent) & FR(fecp, imask);
}

static void clear_int_events(struct net_device *dev, u32 int_events)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fec __iomem *fecp = fep->fec.fecp;

        FW(fecp, ievent, int_events);
}

static void ev_error(struct net_device *dev, u32 int_events)
{
        struct fs_enet_private *fep = netdev_priv(dev);

        dev_warn(fep->dev, "FEC ERROR(s) 0x%x\n", int_events);
}

static int get_regs(struct net_device *dev, void *p, int *sizep)
{
        struct fs_enet_private *fep = netdev_priv(dev);

        if (*sizep < sizeof(struct fec))
                return -EINVAL;

        memcpy_fromio(p, fep->fec.fecp, sizeof(struct fec));

        return 0;
}

static int get_regs_len(struct net_device *dev)
{
        return sizeof(struct fec);
}

static void tx_restart(struct net_device *dev)
{
        /* nothing */
}

/*************************************************************************/

const struct fs_ops fs_fec_ops = {
        .setup_data             = setup_data,
        .cleanup_data           = cleanup_data,
        .set_multicast_list     = set_multicast_list,
        .restart                = restart,
        .stop                   = stop,
        .napi_clear_event       = napi_clear_event_fs,
        .napi_enable            = napi_enable_fs,
        .napi_disable           = napi_disable_fs,
        .rx_bd_done             = rx_bd_done,
        .tx_kickstart           = tx_kickstart,
        .get_int_events         = get_int_events,
        .clear_int_events       = clear_int_events,
        .ev_error               = ev_error,
        .get_regs               = get_regs,
        .get_regs_len           = get_regs_len,
        .tx_restart             = tx_restart,
        .allocate_bd            = allocate_bd,
        .free_bd                = free_bd,
};