// SPDX-License-Identifier: GPL-2.0-only
/*
 *  Amiga Linux/m68k and Linux/PPC Zorro NS8390 Ethernet Driver
 *
 *  (C) Copyright 1998-2000 by some Elitist 680x0 Users(TM)
 *
 *  ---------------------------------------------------------------------------
 *
 *  This program is based on all the other NE2000 drivers for Linux
 *
 *  ---------------------------------------------------------------------------
 *
 *  The Ariadne II and X-Surf are Zorro-II boards containing Realtek RTL8019AS
 *  Ethernet Controllers.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/zorro.h>
#include <linux/jiffies.h>

#include <asm/irq.h>
#include <asm/amigaints.h>
#include <asm/amigahw.h>

#define EI_SHIFT(x)             (ei_local->reg_offset[x])
#define ei_inb(port)            in_8(port)
#define ei_outb(val, port)      out_8(port, val)
#define ei_inb_p(port)          in_8(port)
#define ei_outb_p(val, port)    out_8(port, val)

static const char version[] =
        "8390.c:v1.10cvs 9/23/94 Donald Becker (becker@cesdis.gsfc.nasa.gov)\n";

#include "lib8390.c"

#define DRV_NAME        "zorro8390"

#define NE_BASE         (dev->base_addr)
#define NE_CMD          (0x00 * 2)
#define NE_DATAPORT     (0x10 * 2)      /* NatSemi-defined port window offset */
#define NE_RESET        (0x1f * 2)      /* Issue a read to reset,
                                         * a write to clear. */
#define NE_IO_EXTENT    (0x20 * 2)

#define NE_EN0_ISR      (0x07 * 2)
#define NE_EN0_DCFG     (0x0e * 2)

#define NE_EN0_RSARLO   (0x08 * 2)
#define NE_EN0_RSARHI   (0x09 * 2)
#define NE_EN0_RCNTLO   (0x0a * 2)
#define NE_EN0_RXCR     (0x0c * 2)
#define NE_EN0_TXCR     (0x0d * 2)
#define NE_EN0_RCNTHI   (0x0b * 2)
#define NE_EN0_IMR      (0x0f * 2)

#define NESM_START_PG   0x40    /* First page of TX buffer */
#define NESM_STOP_PG    0x80    /* Last page +1 of RX ring */

#define WORDSWAP(a)     ((((a) >> 8) & 0xff) | ((a) << 8))

static struct card_info {
        zorro_id id;
        const char *name;
        unsigned int offset;
} cards[] = {
        { ZORRO_PROD_VILLAGE_TRONIC_ARIADNE2, "Ariadne II", 0x0600 },
        { ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, "X-Surf", 0x8600 },
};

/* Hard reset the card.  This used to pause for the same period that a
 * 8390 reset command required, but that shouldn't be necessary.
 */
static void zorro8390_reset_8390(struct net_device *dev)
{
        unsigned long reset_start_time = jiffies;
        struct ei_device *ei_local = netdev_priv(dev);

        netif_dbg(ei_local, hw, dev, "resetting - t=%ld...\n", jiffies);

        z_writeb(z_readb(NE_BASE + NE_RESET), NE_BASE + NE_RESET);

        ei_status.txing = 0;
        ei_status.dmaing = 0;

        /* This check _should_not_ be necessary, omit eventually. */
        while ((z_readb(NE_BASE + NE_EN0_ISR) & ENISR_RESET) == 0)
                if (time_after(jiffies, reset_start_time + 2 * HZ / 100)) {
                        netdev_warn(dev, "%s: did not complete\n", __func__);
                        break;
                }
        z_writeb(ENISR_RESET, NE_BASE + NE_EN0_ISR);    /* Ack intr */
}

/* Grab the 8390 specific header. Similar to the block_input routine, but
 * we don't need to be concerned with ring wrap as the header will be at
 * the start of a page, so we optimize accordingly.
 */
static void zorro8390_get_8390_hdr(struct net_device *dev,
                                   struct e8390_pkt_hdr *hdr, int ring_page)
{
        int nic_base = dev->base_addr;
        int cnt;
        short *ptrs;

        /* This *shouldn't* happen.
         * If it does, it's the last thing you'll see
         */
        if (ei_status.dmaing) {
                netdev_warn(dev,
                            "%s: DMAing conflict [DMAstat:%d][irqlock:%d]\n",
                            __func__, ei_status.dmaing, ei_status.irqlock);
                return;
        }

        ei_status.dmaing |= 0x01;
        z_writeb(E8390_NODMA + E8390_PAGE0 + E8390_START, nic_base + NE_CMD);
        z_writeb(ENISR_RDC, nic_base + NE_EN0_ISR);
        z_writeb(sizeof(struct e8390_pkt_hdr), nic_base + NE_EN0_RCNTLO);
        z_writeb(0, nic_base + NE_EN0_RCNTHI);
        z_writeb(0, nic_base + NE_EN0_RSARLO);          /* On page boundary */
        z_writeb(ring_page, nic_base + NE_EN0_RSARHI);
        z_writeb(E8390_RREAD+E8390_START, nic_base + NE_CMD);

        ptrs = (short *)hdr;
        for (cnt = 0; cnt < sizeof(struct e8390_pkt_hdr) >> 1; cnt++)
                *ptrs++ = z_readw(NE_BASE + NE_DATAPORT);

        z_writeb(ENISR_RDC, nic_base + NE_EN0_ISR);     /* Ack intr */

        hdr->count = WORDSWAP(hdr->count);

        ei_status.dmaing &= ~0x01;
}

/* Block input and output, similar to the Crynwr packet driver.
 * If you are porting to a new ethercard, look at the packet driver source
 * for hints. The NEx000 doesn't share the on-board packet memory --
 * you have to put the packet out through the "remote DMA" dataport
 * using z_writeb.
 */
static void zorro8390_block_input(struct net_device *dev, int count,
                                  struct sk_buff *skb, int ring_offset)
{
        int nic_base = dev->base_addr;
        char *buf = skb->data;
        short *ptrs;
        int cnt;

        /* This *shouldn't* happen.
         * If it does, it's the last thing you'll see
         */
        if (ei_status.dmaing) {
                netdev_err(dev, "%s: DMAing conflict [DMAstat:%d][irqlock:%d]\n",
                           __func__, ei_status.dmaing, ei_status.irqlock);
                return;
        }
        ei_status.dmaing |= 0x01;
        z_writeb(E8390_NODMA + E8390_PAGE0 + E8390_START, nic_base + NE_CMD);
        z_writeb(ENISR_RDC, nic_base + NE_EN0_ISR);
        z_writeb(count & 0xff, nic_base + NE_EN0_RCNTLO);
        z_writeb(count >> 8, nic_base + NE_EN0_RCNTHI);
        z_writeb(ring_offset & 0xff, nic_base + NE_EN0_RSARLO);
        z_writeb(ring_offset >> 8, nic_base + NE_EN0_RSARHI);
        z_writeb(E8390_RREAD+E8390_START, nic_base + NE_CMD);
        ptrs = (short *)buf;
        for (cnt = 0; cnt < count >> 1; cnt++)
                *ptrs++ = z_readw(NE_BASE + NE_DATAPORT);
        if (count & 0x01)
                buf[count - 1] = z_readb(NE_BASE + NE_DATAPORT);

        z_writeb(ENISR_RDC, nic_base + NE_EN0_ISR);     /* Ack intr */
        ei_status.dmaing &= ~0x01;
}

static void zorro8390_block_output(struct net_device *dev, int count,
                                   const unsigned char *buf,
                                   const int start_page)
{
        int nic_base = NE_BASE;
        unsigned long dma_start;
        short *ptrs;
        int cnt;

        /* Round the count up for word writes.  Do we need to do this?
         * What effect will an odd byte count have on the 8390?
         * I should check someday.
         */
        if (count & 0x01)
                count++;

        /* This *shouldn't* happen.
         * If it does, it's the last thing you'll see
         */
        if (ei_status.dmaing) {
                netdev_err(dev, "%s: DMAing conflict [DMAstat:%d][irqlock:%d]\n",
                           __func__, ei_status.dmaing, ei_status.irqlock);
                return;
        }
        ei_status.dmaing |= 0x01;
        /* We should already be in page 0, but to be safe... */
        z_writeb(E8390_PAGE0+E8390_START+E8390_NODMA, nic_base + NE_CMD);

        z_writeb(ENISR_RDC, nic_base + NE_EN0_ISR);

        /* Now the normal output. */
        z_writeb(count & 0xff, nic_base + NE_EN0_RCNTLO);
        z_writeb(count >> 8,   nic_base + NE_EN0_RCNTHI);
        z_writeb(0x00, nic_base + NE_EN0_RSARLO);
        z_writeb(start_page, nic_base + NE_EN0_RSARHI);

        z_writeb(E8390_RWRITE + E8390_START, nic_base + NE_CMD);
        ptrs = (short *)buf;
        for (cnt = 0; cnt < count >> 1; cnt++)
                z_writew(*ptrs++, NE_BASE + NE_DATAPORT);

        dma_start = jiffies;

        while ((z_readb(NE_BASE + NE_EN0_ISR) & ENISR_RDC) == 0)
                if (time_after(jiffies, dma_start + 2 * HZ / 100)) {
                                        /* 20ms */
                        netdev_warn(dev, "timeout waiting for Tx RDC\n");
                        zorro8390_reset_8390(dev);
                        __NS8390_init(dev, 1);
                        break;
                }

        z_writeb(ENISR_RDC, nic_base + NE_EN0_ISR);     /* Ack intr */
        ei_status.dmaing &= ~0x01;
}

static int zorro8390_open(struct net_device *dev)
{
        __ei_open(dev);
        return 0;
}

static int zorro8390_close(struct net_device *dev)
{
        struct ei_device *ei_local = netdev_priv(dev);

        netif_dbg(ei_local, ifdown, dev, "Shutting down ethercard\n");
        __ei_close(dev);
        return 0;
}

static void zorro8390_remove_one(struct zorro_dev *z)
{
        struct net_device *dev = zorro_get_drvdata(z);

        unregister_netdev(dev);
        free_irq(IRQ_AMIGA_PORTS, dev);
        release_mem_region(ZTWO_PADDR(dev->base_addr), NE_IO_EXTENT * 2);
        free_netdev(dev);
}

static struct zorro_device_id zorro8390_zorro_tbl[] = {
        { ZORRO_PROD_VILLAGE_TRONIC_ARIADNE2, },
        { ZORRO_PROD_INDIVIDUAL_COMPUTERS_X_SURF, },
        { 0 }
};
MODULE_DEVICE_TABLE(zorro, zorro8390_zorro_tbl);

static const struct net_device_ops zorro8390_netdev_ops = {
        .ndo_open               = zorro8390_open,
        .ndo_stop               = zorro8390_close,
        .ndo_start_xmit         = __ei_start_xmit,
        .ndo_tx_timeout         = __ei_tx_timeout,
        .ndo_get_stats          = __ei_get_stats,
        .ndo_set_rx_mode        = __ei_set_multicast_list,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = eth_mac_addr,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = __ei_poll,
#endif
};

static int zorro8390_init(struct net_device *dev, unsigned long board,
                          const char *name, void __iomem *ioaddr)
{
        int i;
        int err;
        unsigned char SA_prom[32];
        int start_page, stop_page;
        static u32 zorro8390_offsets[16] = {
                0x00, 0x02, 0x04, 0x06, 0x08, 0x0a, 0x0c, 0x0e,
                0x10, 0x12, 0x14, 0x16, 0x18, 0x1a, 0x1c, 0x1e,
        };

        /* Reset card. Who knows what dain-bramaged state it was left in. */
        {
                unsigned long reset_start_time = jiffies;

                z_writeb(z_readb(ioaddr + NE_RESET), ioaddr + NE_RESET);

                while ((z_readb(ioaddr + NE_EN0_ISR) & ENISR_RESET) == 0)
                        if (time_after(jiffies,
                                       reset_start_time + 2 * HZ / 100)) {
                                netdev_warn(dev, "not found (no reset ack)\n");
                                return -ENODEV;
                        }

                z_writeb(0xff, ioaddr + NE_EN0_ISR);    /* Ack all intr. */
        }

        /* Read the 16 bytes of station address PROM.
         * We must first initialize registers,
         * similar to NS8390_init(eifdev, 0).
         * We can't reliably read the SAPROM address without this.
         * (I learned the hard way!).
         */
        {
                static const struct {
                        u32 value;
                        u32 offset;
                } program_seq[] = {
                        {E8390_NODMA + E8390_PAGE0 + E8390_STOP, NE_CMD},
                                                /* Select page 0 */
                        {0x48,  NE_EN0_DCFG},   /* 0x48: Set byte-wide access */
                        {0x00,  NE_EN0_RCNTLO}, /* Clear the count regs */
                        {0x00,  NE_EN0_RCNTHI},
                        {0x00,  NE_EN0_IMR},    /* Mask completion irq */
                        {0xFF,  NE_EN0_ISR},
                        {E8390_RXOFF, NE_EN0_RXCR}, /* 0x20 Set to monitor */
                        {E8390_TXOFF, NE_EN0_TXCR}, /* 0x02 and loopback mode */
                        {32,    NE_EN0_RCNTLO},
                        {0x00,  NE_EN0_RCNTHI},
                        {0x00,  NE_EN0_RSARLO}, /* DMA starting at 0x0000 */
                        {0x00,  NE_EN0_RSARHI},
                        {E8390_RREAD + E8390_START, NE_CMD},
                };
                for (i = 0; i < ARRAY_SIZE(program_seq); i++)
                        z_writeb(program_seq[i].value,
                                 ioaddr + program_seq[i].offset);
        }
        for (i = 0; i < 16; i++) {
                SA_prom[i] = z_readb(ioaddr + NE_DATAPORT);
                (void)z_readb(ioaddr + NE_DATAPORT);
        }

        /* We must set the 8390 for word mode. */
        z_writeb(0x49, ioaddr + NE_EN0_DCFG);
        start_page = NESM_START_PG;
        stop_page = NESM_STOP_PG;

        dev->base_addr = (unsigned long)ioaddr;
        dev->irq = IRQ_AMIGA_PORTS;

        /* Install the Interrupt handler */
        i = request_irq(IRQ_AMIGA_PORTS, __ei_interrupt,
                        IRQF_SHARED, DRV_NAME, dev);
        if (i)
                return i;

        eth_hw_addr_set(dev, SA_prom);

        pr_debug("Found ethernet address: %pM\n", dev->dev_addr);

        ei_status.name = name;
        ei_status.tx_start_page = start_page;
        ei_status.stop_page = stop_page;
        ei_status.word16 = 1;

        ei_status.rx_start_page = start_page + TX_PAGES;

        ei_status.reset_8390 = zorro8390_reset_8390;
        ei_status.block_input = zorro8390_block_input;
        ei_status.block_output = zorro8390_block_output;
        ei_status.get_8390_hdr = zorro8390_get_8390_hdr;
        ei_status.reg_offset = zorro8390_offsets;

        dev->netdev_ops = &zorro8390_netdev_ops;
        __NS8390_init(dev, 0);

        err = register_netdev(dev);
        if (err) {
                free_irq(IRQ_AMIGA_PORTS, dev);
                return err;
        }

        netdev_info(dev, "%s at 0x%08lx, Ethernet Address %pM\n",
                    name, board, dev->dev_addr);

        return 0;
}

static int zorro8390_init_one(struct zorro_dev *z,
                              const struct zorro_device_id *ent)
{
        struct net_device *dev;
        unsigned long board, ioaddr;
        int err, i;

        for (i = ARRAY_SIZE(cards) - 1; i >= 0; i--)
                if (z->id == cards[i].id)
                        break;
        if (i < 0)
                return -ENODEV;

        board = z->resource.start;
        ioaddr = board + cards[i].offset;
        dev = ____alloc_ei_netdev(0);
        if (!dev)
                return -ENOMEM;
        if (!request_mem_region(ioaddr, NE_IO_EXTENT * 2, DRV_NAME)) {
                free_netdev(dev);
                return -EBUSY;
        }
        err = zorro8390_init(dev, board, cards[i].name, ZTWO_VADDR(ioaddr));
        if (err) {
                release_mem_region(ioaddr, NE_IO_EXTENT * 2);
                free_netdev(dev);
                return err;
        }
        zorro_set_drvdata(z, dev);
        return 0;
}

static struct zorro_driver zorro8390_driver = {
        .name           = "zorro8390",
        .id_table       = zorro8390_zorro_tbl,
        .probe          = zorro8390_init_one,
        .remove         = zorro8390_remove_one,
};

static int __init zorro8390_init_module(void)
{
        return zorro_register_driver(&zorro8390_driver);
}

static void __exit zorro8390_cleanup_module(void)
{
        zorro_unregister_driver(&zorro8390_driver);
}

module_init(zorro8390_init_module);
module_exit(zorro8390_cleanup_module);

MODULE_DESCRIPTION("Zorro NS8390-based ethernet driver");
MODULE_LICENSE("GPL");