arc-rimi.c

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/*
 * Linux ARCnet driver - "RIM I" (entirely mem-mapped) cards
 * 
 * Written 1994-1999 by Avery Pennarun.
 * Written 1999-2000 by Martin Mares <[email protected]>.
 * Derived from skeleton.c by Donald Becker.
 *
 * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
 *  for sponsoring the further development of this driver.
 *
 * **********************
 *
 * The original copyright of skeleton.c was as follows:
 *
 * skeleton.c Written 1993 by Donald Becker.
 * Copyright 1993 United States Government as represented by the
 * Director, National Security Agency.  This software may only be used
 * and distributed according to the terms of the GNU General Public License as
 * modified by SRC, incorporated herein by reference.
 *
 * **********************
 *
 * For more details, see drivers/net/arcnet.c
 *
 * **********************
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/bootmem.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <asm/io.h>
#include <linux/arcdevice.h>


#define VERSION "arcnet: RIM I (entirely mem-mapped) support\n"


/* Internal function declarations */

static int arcrimi_probe(struct net_device *dev);
static int arcrimi_found(struct net_device *dev);
static void arcrimi_command(struct net_device *dev, int command);
static int arcrimi_status(struct net_device *dev);
static void arcrimi_setmask(struct net_device *dev, int mask);
static int arcrimi_reset(struct net_device *dev, int really_reset);
static void arcrimi_copy_to_card(struct net_device *dev, int bufnum, int offset,
                 void *buf, int count);
static void arcrimi_copy_from_card(struct net_device *dev, int bufnum, int offset,
                   void *buf, int count);

/* Handy defines for ARCnet specific stuff */

/* Amount of I/O memory used by the card */
#define BUFFER_SIZE (512)
#define MIRROR_SIZE (BUFFER_SIZE*4)

/* COM 9026 controller chip --> ARCnet register addresses */
#define _INTMASK (ioaddr+0) /* writable */
#define _STATUS  (ioaddr+0) /* readable */
#define _COMMAND (ioaddr+1) /* writable, returns random vals on read (?) */
#define _RESET  (ioaddr+8)  /* software reset (on read) */
#define _MEMDATA  (ioaddr+12)   /* Data port for IO-mapped memory */
#define _ADDR_HI  (ioaddr+15)   /* Control registers for said */
#define _ADDR_LO  (ioaddr+14)
#define _CONFIG  (ioaddr+2) /* Configuration register */

#undef ASTATUS
#undef ACOMMAND
#undef AINTMASK

#define ASTATUS()   readb(_STATUS)
#define ACOMMAND(cmd)   writeb((cmd),_COMMAND)
#define AINTMASK(msk)   writeb((msk),_INTMASK)
#define SETCONF()   writeb(lp->config,_CONFIG)


/*
 * We cannot probe for a RIM I card; one reason is I don't know how to reset
 * them.  In fact, we can't even get their node ID automatically.  So, we
 * need to be passed a specific shmem address, IRQ, and node ID.
 */
static int __init arcrimi_probe(struct net_device *dev)
{
    BUGLVL(D_NORMAL) printk(VERSION);
    BUGLVL(D_NORMAL) printk("E-mail me if you actually test the RIM I driver, please!\n");

    BUGLVL(D_NORMAL) printk("Given: node %02Xh, shmem %lXh, irq %d\n",
           dev->dev_addr[0], dev->mem_start, dev->irq);

    if (dev->mem_start <= 0 || dev->irq <= 0) {
        BUGLVL(D_NORMAL) printk("No autoprobe for RIM I; you "
               "must specify the shmem and irq!\n");
        return -ENODEV;
    }
    if (dev->dev_addr[0] == 0) {
        BUGLVL(D_NORMAL) printk("You need to specify your card's station "
               "ID!\n");
        return -ENODEV;
    }
    /*
     * Grab the memory region at mem_start for MIRROR_SIZE bytes.
     * Later in arcrimi_found() the real size will be determined
     * and this reserve will be released and the correct size
     * will be taken.
     */
    if (!request_mem_region(dev->mem_start, MIRROR_SIZE, "arcnet (90xx)")) {
        BUGLVL(D_NORMAL) printk("Card memory already allocated\n");
        return -ENODEV;
    }
    return arcrimi_found(dev);
}

static int check_mirror(unsigned long addr, size_t size)
{
    void __iomem *p;
    int res = -1;

    if (!request_mem_region(addr, size, "arcnet (90xx)"))
        return -1;

    p = ioremap(addr, size);
    if (p) {
        if (readb(p) == TESTvalue)
            res = 1;
        else
            res = 0;
        iounmap(p);
    }

    release_mem_region(addr, size);
    return res;
}

/*
 * Set up the struct net_device associated with this card.  Called after
 * probing succeeds.
 */
static int __init arcrimi_found(struct net_device *dev)
{
    struct arcnet_local *lp;
    unsigned long first_mirror, last_mirror, shmem;
    void __iomem *p;
    int mirror_size;
    int err;

    p = ioremap(dev->mem_start, MIRROR_SIZE);
    if (!p) {
        release_mem_region(dev->mem_start, MIRROR_SIZE);
        BUGMSG(D_NORMAL, "Can't ioremap\n");
        return -ENODEV;
    }

    /* reserve the irq */
    if (request_irq(dev->irq, arcnet_interrupt, 0, "arcnet (RIM I)", dev)) {
        iounmap(p);
        release_mem_region(dev->mem_start, MIRROR_SIZE);
        BUGMSG(D_NORMAL, "Can't get IRQ %d!\n", dev->irq);
        return -ENODEV;
    }

    shmem = dev->mem_start;
    writeb(TESTvalue, p);
    writeb(dev->dev_addr[0], p + 1);    /* actually the node ID */

    /* find the real shared memory start/end points, including mirrors */

    /* guess the actual size of one "memory mirror" - the number of
     * bytes between copies of the shared memory.  On most cards, it's
     * 2k (or there are no mirrors at all) but on some, it's 4k.
     */
    mirror_size = MIRROR_SIZE;
    if (readb(p) == TESTvalue &&
        check_mirror(shmem - MIRROR_SIZE, MIRROR_SIZE) == 0 &&
        check_mirror(shmem - 2 * MIRROR_SIZE, MIRROR_SIZE) == 1)
        mirror_size = 2 * MIRROR_SIZE;

    first_mirror = shmem - mirror_size;
    while (check_mirror(first_mirror, mirror_size) == 1)
        first_mirror -= mirror_size;
    first_mirror += mirror_size;

    last_mirror = shmem + mirror_size;
    while (check_mirror(last_mirror, mirror_size) == 1)
        last_mirror += mirror_size;
    last_mirror -= mirror_size;

    dev->mem_start = first_mirror;
    dev->mem_end = last_mirror + MIRROR_SIZE - 1;

    /* initialize the rest of the device structure. */

    lp = netdev_priv(dev);
    lp->card_name = "RIM I";
    lp->hw.command = arcrimi_command;
    lp->hw.status = arcrimi_status;
    lp->hw.intmask = arcrimi_setmask;
    lp->hw.reset = arcrimi_reset;
    lp->hw.owner = THIS_MODULE;
    lp->hw.copy_to_card = arcrimi_copy_to_card;
    lp->hw.copy_from_card = arcrimi_copy_from_card;

    /*
     * re-reserve the memory region - arcrimi_probe() alloced this reqion
     * but didn't know the real size.  Free that region and then re-get
     * with the correct size.  There is a VERY slim chance this could
     * fail.
     */
    iounmap(p);
    release_mem_region(shmem, MIRROR_SIZE);
    if (!request_mem_region(dev->mem_start,
                dev->mem_end - dev->mem_start + 1,
                "arcnet (90xx)")) {
        BUGMSG(D_NORMAL, "Card memory already allocated\n");
        goto err_free_irq;
    }

    lp->mem_start = ioremap(dev->mem_start, dev->mem_end - dev->mem_start + 1);
    if (!lp->mem_start) {
        BUGMSG(D_NORMAL, "Can't remap device memory!\n");
        goto err_release_mem;
    }

    /* get and check the station ID from offset 1 in shmem */
    dev->dev_addr[0] = readb(lp->mem_start + 1);

    BUGMSG(D_NORMAL, "ARCnet RIM I: station %02Xh found at IRQ %d, "
           "ShMem %lXh (%ld*%d bytes).\n",
           dev->dev_addr[0],
           dev->irq, dev->mem_start,
     (dev->mem_end - dev->mem_start + 1) / mirror_size, mirror_size);

    err = register_netdev(dev);
    if (err)
        goto err_unmap;

    return 0;

err_unmap:
    iounmap(lp->mem_start);
err_release_mem:
    release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
err_free_irq:
    free_irq(dev->irq, dev);
    return -EIO;
}


/*
 * Do a hardware reset on the card, and set up necessary registers.
 *
 * This should be called as little as possible, because it disrupts the
 * token on the network (causes a RECON) and requires a significant delay.
 *
 * However, it does make sure the card is in a defined state.
 */
static int arcrimi_reset(struct net_device *dev, int really_reset)
{
    struct arcnet_local *lp = netdev_priv(dev);
    void __iomem *ioaddr = lp->mem_start + 0x800;

    BUGMSG(D_INIT, "Resetting %s (status=%02Xh)\n", dev->name, ASTATUS());

    if (really_reset) {
        writeb(TESTvalue, ioaddr - 0x800);  /* fake reset */
        return 0;
    }
    ACOMMAND(CFLAGScmd | RESETclear);   /* clear flags & end reset */
    ACOMMAND(CFLAGScmd | CONFIGclear);

    /* enable extended (512-byte) packets */
    ACOMMAND(CONFIGcmd | EXTconf);

    /* done!  return success. */
    return 0;
}

static void arcrimi_setmask(struct net_device *dev, int mask)
{
    struct arcnet_local *lp = netdev_priv(dev);
    void __iomem *ioaddr = lp->mem_start + 0x800;

    AINTMASK(mask);
}

static int arcrimi_status(struct net_device *dev)
{
    struct arcnet_local *lp = netdev_priv(dev);
    void __iomem *ioaddr = lp->mem_start + 0x800;

    return ASTATUS();
}

static void arcrimi_command(struct net_device *dev, int cmd)
{
    struct arcnet_local *lp = netdev_priv(dev);
    void __iomem *ioaddr = lp->mem_start + 0x800;

    ACOMMAND(cmd);
}

static void arcrimi_copy_to_card(struct net_device *dev, int bufnum, int offset,
                 void *buf, int count)
{
    struct arcnet_local *lp = netdev_priv(dev);
    void __iomem *memaddr = lp->mem_start + 0x800 + bufnum * 512 + offset;
    TIME("memcpy_toio", count, memcpy_toio(memaddr, buf, count));
}


static void arcrimi_copy_from_card(struct net_device *dev, int bufnum, int offset,
                   void *buf, int count)
{
    struct arcnet_local *lp = netdev_priv(dev);
    void __iomem *memaddr = lp->mem_start + 0x800 + bufnum * 512 + offset;
    TIME("memcpy_fromio", count, memcpy_fromio(buf, memaddr, count));
}

static int node;
static int io;          /* use the insmod io= irq= node= options */
static int irq;
static char device[9];      /* use eg. device=arc1 to change name */

module_param(node, int, 0);
module_param(io, int, 0);
module_param(irq, int, 0);
module_param_string(device, device, sizeof(device), 0);
MODULE_LICENSE("GPL");

static struct net_device *my_dev;

static int __init arc_rimi_init(void)
{
    struct net_device *dev;

    dev = alloc_arcdev(device);
    if (!dev)
        return -ENOMEM;

    if (node && node != 0xff)
        dev->dev_addr[0] = node;

    dev->mem_start = io;
    dev->irq = irq;
    if (dev->irq == 2)
        dev->irq = 9;

    if (arcrimi_probe(dev)) {
        free_netdev(dev);
        return -EIO;
    }

    my_dev = dev;
    return 0;
}

static void __exit arc_rimi_exit(void)
{
    struct net_device *dev = my_dev;
    struct arcnet_local *lp = netdev_priv(dev);

    unregister_netdev(dev);
    iounmap(lp->mem_start);
    release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
    free_irq(dev->irq, dev);
    free_netdev(dev);
}

#ifndef MODULE
static int __init arcrimi_setup(char *s)
{
    int ints[8];
    s = get_options(s, 8, ints);
    if (!ints[0])
        return 1;
    switch (ints[0]) {
    default:        /* ERROR */
        printk("arcrimi: Too many arguments.\n");
    case 3:     /* Node ID */
        node = ints[3];
    case 2:     /* IRQ */
        irq = ints[2];
    case 1:     /* IO address */
        io = ints[1];
    }
    if (*s)
        snprintf(device, sizeof(device), "%s", s);
    return 1;
}
__setup("arcrimi=", arcrimi_setup);
#endif              /* MODULE */

module_init(arc_rimi_init)
module_exit(arc_rimi_exit)