/*
   * Linux ARCnet driver - "RIM I" (entirely mem-mapped) cards

   *

   * Written 1994-1999 by Avery Pennarun.
   * Written 1999-2000 by Martin Mares <mj@ucw.cz>.
   * 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
   *
   * **********************
   */

  
  #define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt

  #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 <linux/io.h>

  
  #include "arcdevice.h"

  #include "com9026.h"

  /* 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)

  /* 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)
  {

  	if (BUGLVL(D_NORMAL)) {

  		pr_info("%s
  ", "RIM I (entirely mem-mapped) support");
  		pr_info("E-mail me if you actually test the RIM I driver, please!
  ");
  		pr_info("Given: node %02Xh, shmem %lXh, irq %d
  ",
  			dev->dev_addr[0], dev->mem_start, dev->irq);

  	}

  
  	if (dev->mem_start <= 0 || dev->irq <= 0) {

  		if (BUGLVL(D_NORMAL))

  			pr_err("No autoprobe for RIM I; you must specify the shmem and irq!
  ");

  		return -ENODEV;
  	}

  	if (dev->dev_addr[0] == 0) {

  		if (BUGLVL(D_NORMAL))

  			pr_err("You need to specify your card's station ID!
  ");

  		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)")) {

  		if (BUGLVL(D_NORMAL))

  			pr_notice("Card memory already allocated
  ");

  		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 (arcnet_readb(p, COM9026_REG_R_STATUS) == 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);

  		arc_printk(D_NORMAL, dev, "Can't ioremap
  ");

  		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);

  		arc_printk(D_NORMAL, dev, "Can't get IRQ %d!
  ", dev->irq);

  		return -ENODEV;
  	}
  
  	shmem = dev->mem_start;

  	arcnet_writeb(TESTvalue, p, COM9026_REG_W_INTMASK);
  	arcnet_writeb(TESTvalue, p, COM9026_REG_W_COMMAND);
  					/* actually the station/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 (arcnet_readb(p, COM9026_REG_R_STATUS) == 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)")) {

  		arc_printk(D_NORMAL, dev, "Card memory already allocated
  ");

  		goto err_free_irq;
  	}

  	lp->mem_start = ioremap(dev->mem_start,
  				dev->mem_end - dev->mem_start + 1);

  	if (!lp->mem_start) {

  		arc_printk(D_NORMAL, dev, "Can't remap device memory!
  ");

  		goto err_release_mem;
  	}
  
  	/* get and check the station ID from offset 1 in shmem */

  	dev->dev_addr[0] = arcnet_readb(lp->mem_start, COM9026_REG_R_STATION);

  	arc_printk(D_NORMAL, dev, "ARCnet RIM I: station %02Xh found at IRQ %d, ShMem %lXh (%ld*%d bytes)
  ",
  		   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;

  	arc_printk(D_INIT, dev, "Resetting %s (status=%02Xh)
  ",

  		   dev->name, arcnet_readb(ioaddr, COM9026_REG_R_STATUS));

  
  	if (really_reset) {

  		arcnet_writeb(TESTvalue, ioaddr, -0x800);	/* fake reset */

  		return 0;
  	}

  	/* clear flags & end reset */
  	arcnet_writeb(CFLAGScmd | RESETclear, ioaddr, COM9026_REG_W_COMMAND);
  	arcnet_writeb(CFLAGScmd | CONFIGclear, ioaddr, COM9026_REG_W_COMMAND);

  
  	/* enable extended (512-byte) packets */

  	arcnet_writeb(CONFIGcmd | EXTconf, ioaddr, COM9026_REG_W_COMMAND);

  
  	/* 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;

  	arcnet_writeb(mask, ioaddr, COM9026_REG_W_INTMASK);

  }
  
  static int arcrimi_status(struct net_device *dev)
  {

  	struct arcnet_local *lp = netdev_priv(dev);

  	void __iomem *ioaddr = lp->mem_start + 0x800;

  	return arcnet_readb(ioaddr, COM9026_REG_R_STATUS);

  }
  
  static void arcrimi_command(struct net_device *dev, int cmd)
  {

  	struct arcnet_local *lp = netdev_priv(dev);

  	void __iomem *ioaddr = lp->mem_start + 0x800;

  	arcnet_writeb(cmd, ioaddr, COM9026_REG_W_COMMAND);

  }
  
  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(dev, "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(dev, "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 */

  		pr_err("Too many arguments
  ");

  	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)