ethernet: use net core MTU range checking in more drivers

[mirror_ubuntu-zesty-kernel.git] / drivers / net / ethernet / alteon / acenic.c

/*
 * acenic.c: Linux driver for the Alteon AceNIC Gigabit Ethernet card
 *           and other Tigon based cards.
 *
 * Copyright 1998-2002 by Jes Sorensen, <jes@trained-monkey.org>.
 *
 * Thanks to Alteon and 3Com for providing hardware and documentation
 * enabling me to write this driver.
 *
 * A mailing list for discussing the use of this driver has been
 * setup, please subscribe to the lists if you have any questions
 * about the driver. Send mail to linux-acenic-help@sunsite.auc.dk to
 * see how to subscribe.
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Additional credits:
 *   Pete Wyckoff <wyckoff@ca.sandia.gov>: Initial Linux/Alpha and trace
 *       dump support. The trace dump support has not been
 *       integrated yet however.
 *   Troy Benjegerdes: Big Endian (PPC) patches.
 *   Nate Stahl: Better out of memory handling and stats support.
 *   Aman Singla: Nasty race between interrupt handler and tx code dealing
 *                with 'testing the tx_ret_csm and setting tx_full'
 *   David S. Miller <davem@redhat.com>: conversion to new PCI dma mapping
 *                                       infrastructure and Sparc support
 *   Pierrick Pinasseau (CERN): For lending me an Ultra 5 to test the
 *                              driver under Linux/Sparc64
 *   Matt Domsch <Matt_Domsch@dell.com>: Detect Alteon 1000baseT cards
 *                                       ETHTOOL_GDRVINFO support
 *   Chip Salzenberg <chip@valinux.com>: Fix race condition between tx
 *                                       handler and close() cleanup.
 *   Ken Aaker <kdaaker@rchland.vnet.ibm.com>: Correct check for whether
 *                                       memory mapped IO is enabled to
 *                                       make the driver work on RS/6000.
 *   Takayoshi Kouchi <kouchi@hpc.bs1.fc.nec.co.jp>: Identifying problem
 *                                       where the driver would disable
 *                                       bus master mode if it had to disable
 *                                       write and invalidate.
 *   Stephen Hack <stephen_hack@hp.com>: Fixed ace_set_mac_addr for little
 *                                       endian systems.
 *   Val Henson <vhenson@esscom.com>:    Reset Jumbo skb producer and
 *                                       rx producer index when
 *                                       flushing the Jumbo ring.
 *   Hans Grobler <grobh@sun.ac.za>:     Memory leak fixes in the
 *                                       driver init path.
 *   Grant Grundler <grundler@cup.hp.com>: PCI write posting fixes.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/delay.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/sockios.h>
#include <linux/firmware.h>
#include <linux/slab.h>
#include <linux/prefetch.h>
#include <linux/if_vlan.h>

#ifdef SIOCETHTOOL
#include <linux/ethtool.h>
#endif

#include <net/sock.h>
#include <net/ip.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/byteorder.h>
#include <asm/uaccess.h>


#define DRV_NAME "acenic"

#undef INDEX_DEBUG

#ifdef CONFIG_ACENIC_OMIT_TIGON_I
#define ACE_IS_TIGON_I(ap)      0
#define ACE_TX_RING_ENTRIES(ap) MAX_TX_RING_ENTRIES
#else
#define ACE_IS_TIGON_I(ap)      (ap->version == 1)
#define ACE_TX_RING_ENTRIES(ap) ap->tx_ring_entries
#endif

#ifndef PCI_VENDOR_ID_ALTEON
#define PCI_VENDOR_ID_ALTEON            0x12ae
#endif
#ifndef PCI_DEVICE_ID_ALTEON_ACENIC_FIBRE
#define PCI_DEVICE_ID_ALTEON_ACENIC_FIBRE  0x0001
#define PCI_DEVICE_ID_ALTEON_ACENIC_COPPER 0x0002
#endif
#ifndef PCI_DEVICE_ID_3COM_3C985
#define PCI_DEVICE_ID_3COM_3C985        0x0001
#endif
#ifndef PCI_VENDOR_ID_NETGEAR
#define PCI_VENDOR_ID_NETGEAR           0x1385
#define PCI_DEVICE_ID_NETGEAR_GA620     0x620a
#endif
#ifndef PCI_DEVICE_ID_NETGEAR_GA620T
#define PCI_DEVICE_ID_NETGEAR_GA620T    0x630a
#endif


/*
 * Farallon used the DEC vendor ID by mistake and they seem not
 * to care - stinky!
 */
#ifndef PCI_DEVICE_ID_FARALLON_PN9000SX
#define PCI_DEVICE_ID_FARALLON_PN9000SX 0x1a
#endif
#ifndef PCI_DEVICE_ID_FARALLON_PN9100T
#define PCI_DEVICE_ID_FARALLON_PN9100T  0xfa
#endif
#ifndef PCI_VENDOR_ID_SGI
#define PCI_VENDOR_ID_SGI               0x10a9
#endif
#ifndef PCI_DEVICE_ID_SGI_ACENIC
#define PCI_DEVICE_ID_SGI_ACENIC        0x0009
#endif

static const struct pci_device_id acenic_pci_tbl[] = {
        { PCI_VENDOR_ID_ALTEON, PCI_DEVICE_ID_ALTEON_ACENIC_FIBRE,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        { PCI_VENDOR_ID_ALTEON, PCI_DEVICE_ID_ALTEON_ACENIC_COPPER,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        { PCI_VENDOR_ID_3COM, PCI_DEVICE_ID_3COM_3C985,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        { PCI_VENDOR_ID_NETGEAR, PCI_DEVICE_ID_NETGEAR_GA620,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        { PCI_VENDOR_ID_NETGEAR, PCI_DEVICE_ID_NETGEAR_GA620T,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        /*
         * Farallon used the DEC vendor ID on their cards incorrectly,
         * then later Alteon's ID.
         */
        { PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_FARALLON_PN9000SX,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        { PCI_VENDOR_ID_ALTEON, PCI_DEVICE_ID_FARALLON_PN9100T,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        { PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_ACENIC,
          PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, },
        { }
};
MODULE_DEVICE_TABLE(pci, acenic_pci_tbl);

#define ace_sync_irq(irq)       synchronize_irq(irq)

#ifndef offset_in_page
#define offset_in_page(ptr)     ((unsigned long)(ptr) & ~PAGE_MASK)
#endif

#define ACE_MAX_MOD_PARMS       8
#define BOARD_IDX_STATIC        0
#define BOARD_IDX_OVERFLOW      -1

#include "acenic.h"

/*
 * These must be defined before the firmware is included.
 */
#define MAX_TEXT_LEN    96*1024
#define MAX_RODATA_LEN  8*1024
#define MAX_DATA_LEN    2*1024

#ifndef tigon2FwReleaseLocal
#define tigon2FwReleaseLocal 0
#endif

/*
 * This driver currently supports Tigon I and Tigon II based cards
 * including the Alteon AceNIC, the 3Com 3C985[B] and NetGear
 * GA620. The driver should also work on the SGI, DEC and Farallon
 * versions of the card, however I have not been able to test that
 * myself.
 *
 * This card is really neat, it supports receive hardware checksumming
 * and jumbo frames (up to 9000 bytes) and does a lot of work in the
 * firmware. Also the programming interface is quite neat, except for
 * the parts dealing with the i2c eeprom on the card ;-)
 *
 * Using jumbo frames:
 *
 * To enable jumbo frames, simply specify an mtu between 1500 and 9000
 * bytes to ifconfig. Jumbo frames can be enabled or disabled at any time
 * by running `ifconfig eth<X> mtu <MTU>' with <X> being the Ethernet
 * interface number and <MTU> being the MTU value.
 *
 * Module parameters:
 *
 * When compiled as a loadable module, the driver allows for a number
 * of module parameters to be specified. The driver supports the
 * following module parameters:
 *
 *  trace=<val> - Firmware trace level. This requires special traced
 *                firmware to replace the firmware supplied with
 *                the driver - for debugging purposes only.
 *
 *  link=<val>  - Link state. Normally you want to use the default link
 *                parameters set by the driver. This can be used to
 *                override these in case your switch doesn't negotiate
 *                the link properly. Valid values are:
 *         0x0001 - Force half duplex link.
 *         0x0002 - Do not negotiate line speed with the other end.
 *         0x0010 - 10Mbit/sec link.
 *         0x0020 - 100Mbit/sec link.
 *         0x0040 - 1000Mbit/sec link.
 *         0x0100 - Do not negotiate flow control.
 *         0x0200 - Enable RX flow control Y
 *         0x0400 - Enable TX flow control Y (Tigon II NICs only).
 *                Default value is 0x0270, ie. enable link+flow
 *                control negotiation. Negotiating the highest
 *                possible link speed with RX flow control enabled.
 *
 *                When disabling link speed negotiation, only one link
 *                speed is allowed to be specified!
 *
 *  tx_coal_tick=<val> - number of coalescing clock ticks (us) allowed
 *                to wait for more packets to arive before
 *                interrupting the host, from the time the first
 *                packet arrives.
 *
 *  rx_coal_tick=<val> - number of coalescing clock ticks (us) allowed
 *                to wait for more packets to arive in the transmit ring,
 *                before interrupting the host, after transmitting the
 *                first packet in the ring.
 *
 *  max_tx_desc=<val> - maximum number of transmit descriptors
 *                (packets) transmitted before interrupting the host.
 *
 *  max_rx_desc=<val> - maximum number of receive descriptors
 *                (packets) received before interrupting the host.
 *
 *  tx_ratio=<val> - 7 bit value (0 - 63) specifying the split in 64th
 *                increments of the NIC's on board memory to be used for
 *                transmit and receive buffers. For the 1MB NIC app. 800KB
 *                is available, on the 1/2MB NIC app. 300KB is available.
 *                68KB will always be available as a minimum for both
 *                directions. The default value is a 50/50 split.
 *  dis_pci_mem_inval=<val> - disable PCI memory write and invalidate
 *                operations, default (1) is to always disable this as
 *                that is what Alteon does on NT. I have not been able
 *                to measure any real performance differences with
 *                this on my systems. Set <val>=0 if you want to
 *                enable these operations.
 *
 * If you use more than one NIC, specify the parameters for the
 * individual NICs with a comma, ie. trace=0,0x00001fff,0 you want to
 * run tracing on NIC #2 but not on NIC #1 and #3.
 *
 * TODO:
 *
 * - Proper multicast support.
 * - NIC dump support.
 * - More tuning parameters.
 *
 * The mini ring is not used under Linux and I am not sure it makes sense
 * to actually use it.
 *
 * New interrupt handler strategy:
 *
 * The old interrupt handler worked using the traditional method of
 * replacing an skbuff with a new one when a packet arrives. However
 * the rx rings do not need to contain a static number of buffer
 * descriptors, thus it makes sense to move the memory allocation out
 * of the main interrupt handler and do it in a bottom half handler
 * and only allocate new buffers when the number of buffers in the
 * ring is below a certain threshold. In order to avoid starving the
 * NIC under heavy load it is however necessary to force allocation
 * when hitting a minimum threshold. The strategy for alloction is as
 * follows:
 *
 *     RX_LOW_BUF_THRES    - allocate buffers in the bottom half
 *     RX_PANIC_LOW_THRES  - we are very low on buffers, allocate
 *                           the buffers in the interrupt handler
 *     RX_RING_THRES       - maximum number of buffers in the rx ring
 *     RX_MINI_THRES       - maximum number of buffers in the mini ring
 *     RX_JUMBO_THRES      - maximum number of buffers in the jumbo ring
 *
 * One advantagous side effect of this allocation approach is that the
 * entire rx processing can be done without holding any spin lock
 * since the rx rings and registers are totally independent of the tx
 * ring and its registers.  This of course includes the kmalloc's of
 * new skb's. Thus start_xmit can run in parallel with rx processing
 * and the memory allocation on SMP systems.
 *
 * Note that running the skb reallocation in a bottom half opens up
 * another can of races which needs to be handled properly. In
 * particular it can happen that the interrupt handler tries to run
 * the reallocation while the bottom half is either running on another
 * CPU or was interrupted on the same CPU. To get around this the
 * driver uses bitops to prevent the reallocation routines from being
 * reentered.
 *
 * TX handling can also be done without holding any spin lock, wheee
 * this is fun! since tx_ret_csm is only written to by the interrupt
 * handler. The case to be aware of is when shutting down the device
 * and cleaning up where it is necessary to make sure that
 * start_xmit() is not running while this is happening. Well DaveM
 * informs me that this case is already protected against ... bye bye
 * Mr. Spin Lock, it was nice to know you.
 *
 * TX interrupts are now partly disabled so the NIC will only generate
 * TX interrupts for the number of coal ticks, not for the number of
 * TX packets in the queue. This should reduce the number of TX only,
 * ie. when no RX processing is done, interrupts seen.
 */

/*
 * Threshold values for RX buffer allocation - the low water marks for
 * when to start refilling the rings are set to 75% of the ring
 * sizes. It seems to make sense to refill the rings entirely from the
 * intrrupt handler once it gets below the panic threshold, that way
 * we don't risk that the refilling is moved to another CPU when the
 * one running the interrupt handler just got the slab code hot in its
 * cache.
 */
#define RX_RING_SIZE            72
#define RX_MINI_SIZE            64
#define RX_JUMBO_SIZE           48

#define RX_PANIC_STD_THRES      16
#define RX_PANIC_STD_REFILL     (3*RX_PANIC_STD_THRES)/2
#define RX_LOW_STD_THRES        (3*RX_RING_SIZE)/4
#define RX_PANIC_MINI_THRES     12
#define RX_PANIC_MINI_REFILL    (3*RX_PANIC_MINI_THRES)/2
#define RX_LOW_MINI_THRES       (3*RX_MINI_SIZE)/4
#define RX_PANIC_JUMBO_THRES    6
#define RX_PANIC_JUMBO_REFILL   (3*RX_PANIC_JUMBO_THRES)/2
#define RX_LOW_JUMBO_THRES      (3*RX_JUMBO_SIZE)/4


/*
 * Size of the mini ring entries, basically these just should be big
 * enough to take TCP ACKs
 */
#define ACE_MINI_SIZE           100

#define ACE_MINI_BUFSIZE        ACE_MINI_SIZE
#define ACE_STD_BUFSIZE         (ACE_STD_MTU + ETH_HLEN + 4)
#define ACE_JUMBO_BUFSIZE       (ACE_JUMBO_MTU + ETH_HLEN + 4)

/*
 * There seems to be a magic difference in the effect between 995 and 996
 * but little difference between 900 and 995 ... no idea why.
 *
 * There is now a default set of tuning parameters which is set, depending
 * on whether or not the user enables Jumbo frames. It's assumed that if
 * Jumbo frames are enabled, the user wants optimal tuning for that case.
 */
#define DEF_TX_COAL             400 /* 996 */
#define DEF_TX_MAX_DESC         60  /* was 40 */
#define DEF_RX_COAL             120 /* 1000 */
#define DEF_RX_MAX_DESC         25
#define DEF_TX_RATIO            21 /* 24 */

#define DEF_JUMBO_TX_COAL       20
#define DEF_JUMBO_TX_MAX_DESC   60
#define DEF_JUMBO_RX_COAL       30
#define DEF_JUMBO_RX_MAX_DESC   6
#define DEF_JUMBO_TX_RATIO      21

#if tigon2FwReleaseLocal < 20001118
/*
 * Standard firmware and early modifications duplicate
 * IRQ load without this flag (coal timer is never reset).
 * Note that with this flag tx_coal should be less than
 * time to xmit full tx ring.
 * 400usec is not so bad for tx ring size of 128.
 */
#define TX_COAL_INTS_ONLY       1       /* worth it */
#else
/*
 * With modified firmware, this is not necessary, but still useful.
 */
#define TX_COAL_INTS_ONLY       1
#endif

#define DEF_TRACE               0
#define DEF_STAT                (2 * TICKS_PER_SEC)


static int link_state[ACE_MAX_MOD_PARMS];
static int trace[ACE_MAX_MOD_PARMS];
static int tx_coal_tick[ACE_MAX_MOD_PARMS];
static int rx_coal_tick[ACE_MAX_MOD_PARMS];
static int max_tx_desc[ACE_MAX_MOD_PARMS];
static int max_rx_desc[ACE_MAX_MOD_PARMS];
static int tx_ratio[ACE_MAX_MOD_PARMS];
static int dis_pci_mem_inval[ACE_MAX_MOD_PARMS] = {1, 1, 1, 1, 1, 1, 1, 1};

MODULE_AUTHOR("Jes Sorensen <jes@trained-monkey.org>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("AceNIC/3C985/GA620 Gigabit Ethernet driver");
#ifndef CONFIG_ACENIC_OMIT_TIGON_I
MODULE_FIRMWARE("acenic/tg1.bin");
#endif
MODULE_FIRMWARE("acenic/tg2.bin");

module_param_array_named(link, link_state, int, NULL, 0);
module_param_array(trace, int, NULL, 0);
module_param_array(tx_coal_tick, int, NULL, 0);
module_param_array(max_tx_desc, int, NULL, 0);
module_param_array(rx_coal_tick, int, NULL, 0);
module_param_array(max_rx_desc, int, NULL, 0);
module_param_array(tx_ratio, int, NULL, 0);
MODULE_PARM_DESC(link, "AceNIC/3C985/NetGear link state");
MODULE_PARM_DESC(trace, "AceNIC/3C985/NetGear firmware trace level");
MODULE_PARM_DESC(tx_coal_tick, "AceNIC/3C985/GA620 max clock ticks to wait from first tx descriptor arrives");
MODULE_PARM_DESC(max_tx_desc, "AceNIC/3C985/GA620 max number of transmit descriptors to wait");
MODULE_PARM_DESC(rx_coal_tick, "AceNIC/3C985/GA620 max clock ticks to wait from first rx descriptor arrives");
MODULE_PARM_DESC(max_rx_desc, "AceNIC/3C985/GA620 max number of receive descriptors to wait");
MODULE_PARM_DESC(tx_ratio, "AceNIC/3C985/GA620 ratio of NIC memory used for TX/RX descriptors (range 0-63)");


static const char version[] =
  "acenic.c: v0.92 08/05/2002  Jes Sorensen, linux-acenic@SunSITE.dk\n"
  "                            http://home.cern.ch/~jes/gige/acenic.html\n";

static int ace_get_settings(struct net_device *, struct ethtool_cmd *);
static int ace_set_settings(struct net_device *, struct ethtool_cmd *);
static void ace_get_drvinfo(struct net_device *, struct ethtool_drvinfo *);

static const struct ethtool_ops ace_ethtool_ops = {
        .get_settings = ace_get_settings,
        .set_settings = ace_set_settings,
        .get_drvinfo = ace_get_drvinfo,
};

static void ace_watchdog(struct net_device *dev);

static const struct net_device_ops ace_netdev_ops = {
        .ndo_open               = ace_open,
        .ndo_stop               = ace_close,
        .ndo_tx_timeout         = ace_watchdog,
        .ndo_get_stats          = ace_get_stats,
        .ndo_start_xmit         = ace_start_xmit,
        .ndo_set_rx_mode        = ace_set_multicast_list,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = ace_set_mac_addr,
        .ndo_change_mtu         = ace_change_mtu,
};

static int acenic_probe_one(struct pci_dev *pdev,
                            const struct pci_device_id *id)
{
        struct net_device *dev;
        struct ace_private *ap;
        static int boards_found;

        dev = alloc_etherdev(sizeof(struct ace_private));
        if (dev == NULL)
                return -ENOMEM;

        SET_NETDEV_DEV(dev, &pdev->dev);

        ap = netdev_priv(dev);
        ap->pdev = pdev;
        ap->name = pci_name(pdev);

        dev->features |= NETIF_F_SG | NETIF_F_IP_CSUM;
        dev->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;

        dev->watchdog_timeo = 5*HZ;
        dev->min_mtu = 0;
        dev->max_mtu = ACE_JUMBO_MTU;

        dev->netdev_ops = &ace_netdev_ops;
        dev->ethtool_ops = &ace_ethtool_ops;

        /* we only display this string ONCE */
        if (!boards_found)
                printk(version);

        if (pci_enable_device(pdev))
                goto fail_free_netdev;

        /*
         * Enable master mode before we start playing with the
         * pci_command word since pci_set_master() will modify
         * it.
         */
        pci_set_master(pdev);

        pci_read_config_word(pdev, PCI_COMMAND, &ap->pci_command);

        /* OpenFirmware on Mac's does not set this - DOH.. */
        if (!(ap->pci_command & PCI_COMMAND_MEMORY)) {
                printk(KERN_INFO "%s: Enabling PCI Memory Mapped "
                       "access - was not enabled by BIOS/Firmware\n",
                       ap->name);
                ap->pci_command = ap->pci_command | PCI_COMMAND_MEMORY;
                pci_write_config_word(ap->pdev, PCI_COMMAND,
                                      ap->pci_command);
                wmb();
        }

        pci_read_config_byte(pdev, PCI_LATENCY_TIMER, &ap->pci_latency);
        if (ap->pci_latency <= 0x40) {
                ap->pci_latency = 0x40;
                pci_write_config_byte(pdev, PCI_LATENCY_TIMER, ap->pci_latency);
        }

        /*
         * Remap the regs into kernel space - this is abuse of
         * dev->base_addr since it was means for I/O port
         * addresses but who gives a damn.
         */
        dev->base_addr = pci_resource_start(pdev, 0);
        ap->regs = ioremap(dev->base_addr, 0x4000);
        if (!ap->regs) {
                printk(KERN_ERR "%s:  Unable to map I/O register, "
                       "AceNIC %i will be disabled.\n",
                       ap->name, boards_found);
                goto fail_free_netdev;
        }

        switch(pdev->vendor) {
        case PCI_VENDOR_ID_ALTEON:
                if (pdev->device == PCI_DEVICE_ID_FARALLON_PN9100T) {
                        printk(KERN_INFO "%s: Farallon PN9100-T ",
                               ap->name);
                } else {
                        printk(KERN_INFO "%s: Alteon AceNIC ",
                               ap->name);
                }
                break;
        case PCI_VENDOR_ID_3COM:
                printk(KERN_INFO "%s: 3Com 3C985 ", ap->name);
                break;
        case PCI_VENDOR_ID_NETGEAR:
                printk(KERN_INFO "%s: NetGear GA620 ", ap->name);
                break;
        case PCI_VENDOR_ID_DEC:
                if (pdev->device == PCI_DEVICE_ID_FARALLON_PN9000SX) {
                        printk(KERN_INFO "%s: Farallon PN9000-SX ",
                               ap->name);
                        break;
                }
        case PCI_VENDOR_ID_SGI:
                printk(KERN_INFO "%s: SGI AceNIC ", ap->name);
                break;
        default:
                printk(KERN_INFO "%s: Unknown AceNIC ", ap->name);
                break;
        }

        printk("Gigabit Ethernet at 0x%08lx, ", dev->base_addr);
        printk("irq %d\n", pdev->irq);

#ifdef CONFIG_ACENIC_OMIT_TIGON_I
        if ((readl(&ap->regs->HostCtrl) >> 28) == 4) {
                printk(KERN_ERR "%s: Driver compiled without Tigon I"
                       " support - NIC disabled\n", dev->name);
                goto fail_uninit;
        }
#endif

        if (ace_allocate_descriptors(dev))
                goto fail_free_netdev;

#ifdef MODULE
        if (boards_found >= ACE_MAX_MOD_PARMS)
                ap->board_idx = BOARD_IDX_OVERFLOW;
        else
                ap->board_idx = boards_found;
#else
        ap->board_idx = BOARD_IDX_STATIC;
#endif

        if (ace_init(dev))
                goto fail_free_netdev;

        if (register_netdev(dev)) {
                printk(KERN_ERR "acenic: device registration failed\n");
                goto fail_uninit;
        }
        ap->name = dev->name;

        if (ap->pci_using_dac)
                dev->features |= NETIF_F_HIGHDMA;

        pci_set_drvdata(pdev, dev);

        boards_found++;
        return 0;

 fail_uninit:
        ace_init_cleanup(dev);
 fail_free_netdev:
        free_netdev(dev);
        return -ENODEV;
}

static void acenic_remove_one(struct pci_dev *pdev)
{
        struct net_device *dev = pci_get_drvdata(pdev);
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        short i;

        unregister_netdev(dev);

        writel(readl(&regs->CpuCtrl) | CPU_HALT, &regs->CpuCtrl);
        if (ap->version >= 2)
                writel(readl(&regs->CpuBCtrl) | CPU_HALT, &regs->CpuBCtrl);

        /*
         * This clears any pending interrupts
         */
        writel(1, &regs->Mb0Lo);
        readl(&regs->CpuCtrl);  /* flush */

        /*
         * Make sure no other CPUs are processing interrupts
         * on the card before the buffers are being released.
         * Otherwise one might experience some `interesting'
         * effects.
         *
         * Then release the RX buffers - jumbo buffers were
         * already released in ace_close().
         */
        ace_sync_irq(dev->irq);

        for (i = 0; i < RX_STD_RING_ENTRIES; i++) {
                struct sk_buff *skb = ap->skb->rx_std_skbuff[i].skb;

                if (skb) {
                        struct ring_info *ringp;
                        dma_addr_t mapping;

                        ringp = &ap->skb->rx_std_skbuff[i];
                        mapping = dma_unmap_addr(ringp, mapping);
                        pci_unmap_page(ap->pdev, mapping,
                                       ACE_STD_BUFSIZE,
                                       PCI_DMA_FROMDEVICE);

                        ap->rx_std_ring[i].size = 0;
                        ap->skb->rx_std_skbuff[i].skb = NULL;
                        dev_kfree_skb(skb);
                }
        }

        if (ap->version >= 2) {
                for (i = 0; i < RX_MINI_RING_ENTRIES; i++) {
                        struct sk_buff *skb = ap->skb->rx_mini_skbuff[i].skb;

                        if (skb) {
                                struct ring_info *ringp;
                                dma_addr_t mapping;

                                ringp = &ap->skb->rx_mini_skbuff[i];
                                mapping = dma_unmap_addr(ringp,mapping);
                                pci_unmap_page(ap->pdev, mapping,
                                               ACE_MINI_BUFSIZE,
                                               PCI_DMA_FROMDEVICE);

                                ap->rx_mini_ring[i].size = 0;
                                ap->skb->rx_mini_skbuff[i].skb = NULL;
                                dev_kfree_skb(skb);
                        }
                }
        }

        for (i = 0; i < RX_JUMBO_RING_ENTRIES; i++) {
                struct sk_buff *skb = ap->skb->rx_jumbo_skbuff[i].skb;
                if (skb) {
                        struct ring_info *ringp;
                        dma_addr_t mapping;

                        ringp = &ap->skb->rx_jumbo_skbuff[i];
                        mapping = dma_unmap_addr(ringp, mapping);
                        pci_unmap_page(ap->pdev, mapping,
                                       ACE_JUMBO_BUFSIZE,
                                       PCI_DMA_FROMDEVICE);

                        ap->rx_jumbo_ring[i].size = 0;
                        ap->skb->rx_jumbo_skbuff[i].skb = NULL;
                        dev_kfree_skb(skb);
                }
        }

        ace_init_cleanup(dev);
        free_netdev(dev);
}

static struct pci_driver acenic_pci_driver = {
        .name           = "acenic",
        .id_table       = acenic_pci_tbl,
        .probe          = acenic_probe_one,
        .remove         = acenic_remove_one,
};

static void ace_free_descriptors(struct net_device *dev)
{
        struct ace_private *ap = netdev_priv(dev);
        int size;

        if (ap->rx_std_ring != NULL) {
                size = (sizeof(struct rx_desc) *
                        (RX_STD_RING_ENTRIES +
                         RX_JUMBO_RING_ENTRIES +
                         RX_MINI_RING_ENTRIES +
                         RX_RETURN_RING_ENTRIES));
                pci_free_consistent(ap->pdev, size, ap->rx_std_ring,
                                    ap->rx_ring_base_dma);
                ap->rx_std_ring = NULL;
                ap->rx_jumbo_ring = NULL;
                ap->rx_mini_ring = NULL;
                ap->rx_return_ring = NULL;
        }
        if (ap->evt_ring != NULL) {
                size = (sizeof(struct event) * EVT_RING_ENTRIES);
                pci_free_consistent(ap->pdev, size, ap->evt_ring,
                                    ap->evt_ring_dma);
                ap->evt_ring = NULL;
        }
        if (ap->tx_ring != NULL && !ACE_IS_TIGON_I(ap)) {
                size = (sizeof(struct tx_desc) * MAX_TX_RING_ENTRIES);
                pci_free_consistent(ap->pdev, size, ap->tx_ring,
                                    ap->tx_ring_dma);
        }
        ap->tx_ring = NULL;

        if (ap->evt_prd != NULL) {
                pci_free_consistent(ap->pdev, sizeof(u32),
                                    (void *)ap->evt_prd, ap->evt_prd_dma);
                ap->evt_prd = NULL;
        }
        if (ap->rx_ret_prd != NULL) {
                pci_free_consistent(ap->pdev, sizeof(u32),
                                    (void *)ap->rx_ret_prd,
                                    ap->rx_ret_prd_dma);
                ap->rx_ret_prd = NULL;
        }
        if (ap->tx_csm != NULL) {
                pci_free_consistent(ap->pdev, sizeof(u32),
                                    (void *)ap->tx_csm, ap->tx_csm_dma);
                ap->tx_csm = NULL;
        }
}


static int ace_allocate_descriptors(struct net_device *dev)
{
        struct ace_private *ap = netdev_priv(dev);
        int size;

        size = (sizeof(struct rx_desc) *
                (RX_STD_RING_ENTRIES +
                 RX_JUMBO_RING_ENTRIES +
                 RX_MINI_RING_ENTRIES +
                 RX_RETURN_RING_ENTRIES));

        ap->rx_std_ring = pci_alloc_consistent(ap->pdev, size,
                                               &ap->rx_ring_base_dma);
        if (ap->rx_std_ring == NULL)
                goto fail;

        ap->rx_jumbo_ring = ap->rx_std_ring + RX_STD_RING_ENTRIES;
        ap->rx_mini_ring = ap->rx_jumbo_ring + RX_JUMBO_RING_ENTRIES;
        ap->rx_return_ring = ap->rx_mini_ring + RX_MINI_RING_ENTRIES;

        size = (sizeof(struct event) * EVT_RING_ENTRIES);

        ap->evt_ring = pci_alloc_consistent(ap->pdev, size, &ap->evt_ring_dma);

        if (ap->evt_ring == NULL)
                goto fail;

        /*
         * Only allocate a host TX ring for the Tigon II, the Tigon I
         * has to use PCI registers for this ;-(
         */
        if (!ACE_IS_TIGON_I(ap)) {
                size = (sizeof(struct tx_desc) * MAX_TX_RING_ENTRIES);

                ap->tx_ring = pci_alloc_consistent(ap->pdev, size,
                                                   &ap->tx_ring_dma);

                if (ap->tx_ring == NULL)
                        goto fail;
        }

        ap->evt_prd = pci_alloc_consistent(ap->pdev, sizeof(u32),
                                           &ap->evt_prd_dma);
        if (ap->evt_prd == NULL)
                goto fail;

        ap->rx_ret_prd = pci_alloc_consistent(ap->pdev, sizeof(u32),
                                              &ap->rx_ret_prd_dma);
        if (ap->rx_ret_prd == NULL)
                goto fail;

        ap->tx_csm = pci_alloc_consistent(ap->pdev, sizeof(u32),
                                          &ap->tx_csm_dma);
        if (ap->tx_csm == NULL)
                goto fail;

        return 0;

fail:
        /* Clean up. */
        ace_init_cleanup(dev);
        return 1;
}


/*
 * Generic cleanup handling data allocated during init. Used when the
 * module is unloaded or if an error occurs during initialization
 */
static void ace_init_cleanup(struct net_device *dev)
{
        struct ace_private *ap;

        ap = netdev_priv(dev);

        ace_free_descriptors(dev);

        if (ap->info)
                pci_free_consistent(ap->pdev, sizeof(struct ace_info),
                                    ap->info, ap->info_dma);
        kfree(ap->skb);
        kfree(ap->trace_buf);

        if (dev->irq)
                free_irq(dev->irq, dev);

        iounmap(ap->regs);
}


/*
 * Commands are considered to be slow.
 */
static inline void ace_issue_cmd(struct ace_regs __iomem *regs, struct cmd *cmd)
{
        u32 idx;

        idx = readl(&regs->CmdPrd);

        writel(*(u32 *)(cmd), &regs->CmdRng[idx]);
        idx = (idx + 1) % CMD_RING_ENTRIES;

        writel(idx, &regs->CmdPrd);
}


static int ace_init(struct net_device *dev)
{
        struct ace_private *ap;
        struct ace_regs __iomem *regs;
        struct ace_info *info = NULL;
        struct pci_dev *pdev;
        unsigned long myjif;
        u64 tmp_ptr;
        u32 tig_ver, mac1, mac2, tmp, pci_state;
        int board_idx, ecode = 0;
        short i;
        unsigned char cache_size;

        ap = netdev_priv(dev);
        regs = ap->regs;

        board_idx = ap->board_idx;

        /*
         * aman@sgi.com - its useful to do a NIC reset here to
         * address the `Firmware not running' problem subsequent
         * to any crashes involving the NIC
         */
        writel(HW_RESET | (HW_RESET << 24), &regs->HostCtrl);
        readl(&regs->HostCtrl);         /* PCI write posting */
        udelay(5);

        /*
         * Don't access any other registers before this point!
         */
#ifdef __BIG_ENDIAN
        /*
         * This will most likely need BYTE_SWAP once we switch
         * to using __raw_writel()
         */
        writel((WORD_SWAP | CLR_INT | ((WORD_SWAP | CLR_INT) << 24)),
               &regs->HostCtrl);
#else
        writel((CLR_INT | WORD_SWAP | ((CLR_INT | WORD_SWAP) << 24)),
               &regs->HostCtrl);
#endif
        readl(&regs->HostCtrl);         /* PCI write posting */

        /*
         * Stop the NIC CPU and clear pending interrupts
         */
        writel(readl(&regs->CpuCtrl) | CPU_HALT, &regs->CpuCtrl);
        readl(&regs->CpuCtrl);          /* PCI write posting */
        writel(0, &regs->Mb0Lo);

        tig_ver = readl(&regs->HostCtrl) >> 28;

        switch(tig_ver){
#ifndef CONFIG_ACENIC_OMIT_TIGON_I
        case 4:
        case 5:
                printk(KERN_INFO "  Tigon I  (Rev. %i), Firmware: %i.%i.%i, ",
                       tig_ver, ap->firmware_major, ap->firmware_minor,
                       ap->firmware_fix);
                writel(0, &regs->LocalCtrl);
                ap->version = 1;
                ap->tx_ring_entries = TIGON_I_TX_RING_ENTRIES;
                break;
#endif
        case 6:
                printk(KERN_INFO "  Tigon II (Rev. %i), Firmware: %i.%i.%i, ",
                       tig_ver, ap->firmware_major, ap->firmware_minor,
                       ap->firmware_fix);
                writel(readl(&regs->CpuBCtrl) | CPU_HALT, &regs->CpuBCtrl);
                readl(&regs->CpuBCtrl);         /* PCI write posting */
                /*
                 * The SRAM bank size does _not_ indicate the amount
                 * of memory on the card, it controls the _bank_ size!
                 * Ie. a 1MB AceNIC will have two banks of 512KB.
                 */
                writel(SRAM_BANK_512K, &regs->LocalCtrl);
                writel(SYNC_SRAM_TIMING, &regs->MiscCfg);
                ap->version = 2;
                ap->tx_ring_entries = MAX_TX_RING_ENTRIES;
                break;
        default:
                printk(KERN_WARNING "  Unsupported Tigon version detected "
                       "(%i)\n", tig_ver);
                ecode = -ENODEV;
                goto init_error;
        }

        /*
         * ModeStat _must_ be set after the SRAM settings as this change
         * seems to corrupt the ModeStat and possible other registers.
         * The SRAM settings survive resets and setting it to the same
         * value a second time works as well. This is what caused the
         * `Firmware not running' problem on the Tigon II.
         */
#ifdef __BIG_ENDIAN
        writel(ACE_BYTE_SWAP_DMA | ACE_WARN | ACE_FATAL | ACE_BYTE_SWAP_BD |
               ACE_WORD_SWAP_BD | ACE_NO_JUMBO_FRAG, &regs->ModeStat);
#else
        writel(ACE_BYTE_SWAP_DMA | ACE_WARN | ACE_FATAL |
               ACE_WORD_SWAP_BD | ACE_NO_JUMBO_FRAG, &regs->ModeStat);
#endif
        readl(&regs->ModeStat);         /* PCI write posting */

        mac1 = 0;
        for(i = 0; i < 4; i++) {
                int t;

                mac1 = mac1 << 8;
                t = read_eeprom_byte(dev, 0x8c+i);
                if (t < 0) {
                        ecode = -EIO;
                        goto init_error;
                } else
                        mac1 |= (t & 0xff);
        }
        mac2 = 0;
        for(i = 4; i < 8; i++) {
                int t;

                mac2 = mac2 << 8;
                t = read_eeprom_byte(dev, 0x8c+i);
                if (t < 0) {
                        ecode = -EIO;
                        goto init_error;
                } else
                        mac2 |= (t & 0xff);
        }

        writel(mac1, &regs->MacAddrHi);
        writel(mac2, &regs->MacAddrLo);

        dev->dev_addr[0] = (mac1 >> 8) & 0xff;
        dev->dev_addr[1] = mac1 & 0xff;
        dev->dev_addr[2] = (mac2 >> 24) & 0xff;
        dev->dev_addr[3] = (mac2 >> 16) & 0xff;
        dev->dev_addr[4] = (mac2 >> 8) & 0xff;
        dev->dev_addr[5] = mac2 & 0xff;

        printk("MAC: %pM\n", dev->dev_addr);

        /*
         * Looks like this is necessary to deal with on all architectures,
         * even this %$#%$# N440BX Intel based thing doesn't get it right.
         * Ie. having two NICs in the machine, one will have the cache
         * line set at boot time, the other will not.
         */
        pdev = ap->pdev;
        pci_read_config_byte(pdev, PCI_CACHE_LINE_SIZE, &cache_size);
        cache_size <<= 2;
        if (cache_size != SMP_CACHE_BYTES) {
                printk(KERN_INFO "  PCI cache line size set incorrectly "
                       "(%i bytes) by BIOS/FW, ", cache_size);
                if (cache_size > SMP_CACHE_BYTES)
                        printk("expecting %i\n", SMP_CACHE_BYTES);
                else {
                        printk("correcting to %i\n", SMP_CACHE_BYTES);
                        pci_write_config_byte(pdev, PCI_CACHE_LINE_SIZE,
                                              SMP_CACHE_BYTES >> 2);
                }
        }

        pci_state = readl(&regs->PciState);
        printk(KERN_INFO "  PCI bus width: %i bits, speed: %iMHz, "
               "latency: %i clks\n",
                (pci_state & PCI_32BIT) ? 32 : 64,
                (pci_state & PCI_66MHZ) ? 66 : 33,
                ap->pci_latency);

        /*
         * Set the max DMA transfer size. Seems that for most systems
         * the performance is better when no MAX parameter is
         * set. However for systems enabling PCI write and invalidate,
         * DMA writes must be set to the L1 cache line size to get
         * optimal performance.
         *
         * The default is now to turn the PCI write and invalidate off
         * - that is what Alteon does for NT.
         */
        tmp = READ_CMD_MEM | WRITE_CMD_MEM;
        if (ap->version >= 2) {
                tmp |= (MEM_READ_MULTIPLE | (pci_state & PCI_66MHZ));
                /*
                 * Tuning parameters only supported for 8 cards
                 */
                if (board_idx == BOARD_IDX_OVERFLOW ||
                    dis_pci_mem_inval[board_idx]) {
                        if (ap->pci_command & PCI_COMMAND_INVALIDATE) {
                                ap->pci_command &= ~PCI_COMMAND_INVALIDATE;
                                pci_write_config_word(pdev, PCI_COMMAND,
                                                      ap->pci_command);
                                printk(KERN_INFO "  Disabling PCI memory "
                                       "write and invalidate\n");
                        }
                } else if (ap->pci_command & PCI_COMMAND_INVALIDATE) {
                        printk(KERN_INFO "  PCI memory write & invalidate "
                               "enabled by BIOS, enabling counter measures\n");

                        switch(SMP_CACHE_BYTES) {
                        case 16:
                                tmp |= DMA_WRITE_MAX_16;
                                break;
                        case 32:
                                tmp |= DMA_WRITE_MAX_32;
                                break;
                        case 64:
                                tmp |= DMA_WRITE_MAX_64;
                                break;
                        case 128:
                                tmp |= DMA_WRITE_MAX_128;
                                break;
                        default:
                                printk(KERN_INFO "  Cache line size %i not "
                                       "supported, PCI write and invalidate "
                                       "disabled\n", SMP_CACHE_BYTES);
                                ap->pci_command &= ~PCI_COMMAND_INVALIDATE;
                                pci_write_config_word(pdev, PCI_COMMAND,
                                                      ap->pci_command);
                        }
                }
        }

#ifdef __sparc__
        /*
         * On this platform, we know what the best dma settings
         * are.  We use 64-byte maximum bursts, because if we
         * burst larger than the cache line size (or even cross
         * a 64byte boundary in a single burst) the UltraSparc
         * PCI controller will disconnect at 64-byte multiples.
         *
         * Read-multiple will be properly enabled above, and when
         * set will give the PCI controller proper hints about
         * prefetching.
         */
        tmp &= ~DMA_READ_WRITE_MASK;
        tmp |= DMA_READ_MAX_64;
        tmp |= DMA_WRITE_MAX_64;
#endif
#ifdef __alpha__
        tmp &= ~DMA_READ_WRITE_MASK;
        tmp |= DMA_READ_MAX_128;
        /*
         * All the docs say MUST NOT. Well, I did.
         * Nothing terrible happens, if we load wrong size.
         * Bit w&i still works better!
         */
        tmp |= DMA_WRITE_MAX_128;
#endif
        writel(tmp, &regs->PciState);

#if 0
        /*
         * The Host PCI bus controller driver has to set FBB.
         * If all devices on that PCI bus support FBB, then the controller
         * can enable FBB support in the Host PCI Bus controller (or on
         * the PCI-PCI bridge if that applies).
         * -ggg
         */
        /*
         * I have received reports from people having problems when this
         * bit is enabled.
         */
        if (!(ap->pci_command & PCI_COMMAND_FAST_BACK)) {
                printk(KERN_INFO "  Enabling PCI Fast Back to Back\n");
                ap->pci_command |= PCI_COMMAND_FAST_BACK;
                pci_write_config_word(pdev, PCI_COMMAND, ap->pci_command);
        }
#endif

        /*
         * Configure DMA attributes.
         */
        if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(64))) {
                ap->pci_using_dac = 1;
        } else if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
                ap->pci_using_dac = 0;
        } else {
                ecode = -ENODEV;
                goto init_error;
        }

        /*
         * Initialize the generic info block and the command+event rings
         * and the control blocks for the transmit and receive rings
         * as they need to be setup once and for all.
         */
        if (!(info = pci_alloc_consistent(ap->pdev, sizeof(struct ace_info),
                                          &ap->info_dma))) {
                ecode = -EAGAIN;
                goto init_error;
        }
        ap->info = info;

        /*
         * Get the memory for the skb rings.
         */
        if (!(ap->skb = kmalloc(sizeof(struct ace_skb), GFP_KERNEL))) {
                ecode = -EAGAIN;
                goto init_error;
        }

        ecode = request_irq(pdev->irq, ace_interrupt, IRQF_SHARED,
                            DRV_NAME, dev);
        if (ecode) {
                printk(KERN_WARNING "%s: Requested IRQ %d is busy\n",
                       DRV_NAME, pdev->irq);
                goto init_error;
        } else
                dev->irq = pdev->irq;

#ifdef INDEX_DEBUG
        spin_lock_init(&ap->debug_lock);
        ap->last_tx = ACE_TX_RING_ENTRIES(ap) - 1;
        ap->last_std_rx = 0;
        ap->last_mini_rx = 0;
#endif

        memset(ap->info, 0, sizeof(struct ace_info));
        memset(ap->skb, 0, sizeof(struct ace_skb));

        ecode = ace_load_firmware(dev);
        if (ecode)
                goto init_error;

        ap->fw_running = 0;

        tmp_ptr = ap->info_dma;
        writel(tmp_ptr >> 32, &regs->InfoPtrHi);
        writel(tmp_ptr & 0xffffffff, &regs->InfoPtrLo);

        memset(ap->evt_ring, 0, EVT_RING_ENTRIES * sizeof(struct event));

        set_aceaddr(&info->evt_ctrl.rngptr, ap->evt_ring_dma);
        info->evt_ctrl.flags = 0;

        *(ap->evt_prd) = 0;
        wmb();
        set_aceaddr(&info->evt_prd_ptr, ap->evt_prd_dma);
        writel(0, &regs->EvtCsm);

        set_aceaddr(&info->cmd_ctrl.rngptr, 0x100);
        info->cmd_ctrl.flags = 0;
        info->cmd_ctrl.max_len = 0;

        for (i = 0; i < CMD_RING_ENTRIES; i++)
                writel(0, &regs->CmdRng[i]);

        writel(0, &regs->CmdPrd);
        writel(0, &regs->CmdCsm);

        tmp_ptr = ap->info_dma;
        tmp_ptr += (unsigned long) &(((struct ace_info *)0)->s.stats);
        set_aceaddr(&info->stats2_ptr, (dma_addr_t) tmp_ptr);

        set_aceaddr(&info->rx_std_ctrl.rngptr, ap->rx_ring_base_dma);
        info->rx_std_ctrl.max_len = ACE_STD_BUFSIZE;
        info->rx_std_ctrl.flags =
          RCB_FLG_TCP_UDP_SUM | RCB_FLG_NO_PSEUDO_HDR | RCB_FLG_VLAN_ASSIST;

        memset(ap->rx_std_ring, 0,
               RX_STD_RING_ENTRIES * sizeof(struct rx_desc));

        for (i = 0; i < RX_STD_RING_ENTRIES; i++)
                ap->rx_std_ring[i].flags = BD_FLG_TCP_UDP_SUM;

        ap->rx_std_skbprd = 0;
        atomic_set(&ap->cur_rx_bufs, 0);

        set_aceaddr(&info->rx_jumbo_ctrl.rngptr,
                    (ap->rx_ring_base_dma +
                     (sizeof(struct rx_desc) * RX_STD_RING_ENTRIES)));
        info->rx_jumbo_ctrl.max_len = 0;
        info->rx_jumbo_ctrl.flags =
          RCB_FLG_TCP_UDP_SUM | RCB_FLG_NO_PSEUDO_HDR | RCB_FLG_VLAN_ASSIST;

        memset(ap->rx_jumbo_ring, 0,
               RX_JUMBO_RING_ENTRIES * sizeof(struct rx_desc));

        for (i = 0; i < RX_JUMBO_RING_ENTRIES; i++)
                ap->rx_jumbo_ring[i].flags = BD_FLG_TCP_UDP_SUM | BD_FLG_JUMBO;

        ap->rx_jumbo_skbprd = 0;
        atomic_set(&ap->cur_jumbo_bufs, 0);

        memset(ap->rx_mini_ring, 0,
               RX_MINI_RING_ENTRIES * sizeof(struct rx_desc));

        if (ap->version >= 2) {
                set_aceaddr(&info->rx_mini_ctrl.rngptr,
                            (ap->rx_ring_base_dma +
                             (sizeof(struct rx_desc) *
                              (RX_STD_RING_ENTRIES +
                               RX_JUMBO_RING_ENTRIES))));
                info->rx_mini_ctrl.max_len = ACE_MINI_SIZE;
                info->rx_mini_ctrl.flags =
                  RCB_FLG_TCP_UDP_SUM|RCB_FLG_NO_PSEUDO_HDR|RCB_FLG_VLAN_ASSIST;

                for (i = 0; i < RX_MINI_RING_ENTRIES; i++)
                        ap->rx_mini_ring[i].flags =
                                BD_FLG_TCP_UDP_SUM | BD_FLG_MINI;
        } else {
                set_aceaddr(&info->rx_mini_ctrl.rngptr, 0);
                info->rx_mini_ctrl.flags = RCB_FLG_RNG_DISABLE;
                info->rx_mini_ctrl.max_len = 0;
        }

        ap->rx_mini_skbprd = 0;
        atomic_set(&ap->cur_mini_bufs, 0);

        set_aceaddr(&info->rx_return_ctrl.rngptr,
                    (ap->rx_ring_base_dma +
                     (sizeof(struct rx_desc) *
                      (RX_STD_RING_ENTRIES +
                       RX_JUMBO_RING_ENTRIES +
                       RX_MINI_RING_ENTRIES))));
        info->rx_return_ctrl.flags = 0;
        info->rx_return_ctrl.max_len = RX_RETURN_RING_ENTRIES;

        memset(ap->rx_return_ring, 0,
               RX_RETURN_RING_ENTRIES * sizeof(struct rx_desc));

        set_aceaddr(&info->rx_ret_prd_ptr, ap->rx_ret_prd_dma);
        *(ap->rx_ret_prd) = 0;

        writel(TX_RING_BASE, &regs->WinBase);

        if (ACE_IS_TIGON_I(ap)) {
                ap->tx_ring = (__force struct tx_desc *) regs->Window;
                for (i = 0; i < (TIGON_I_TX_RING_ENTRIES
                                 * sizeof(struct tx_desc)) / sizeof(u32); i++)
                        writel(0, (__force void __iomem *)ap->tx_ring  + i * 4);

                set_aceaddr(&info->tx_ctrl.rngptr, TX_RING_BASE);
        } else {
                memset(ap->tx_ring, 0,
                       MAX_TX_RING_ENTRIES * sizeof(struct tx_desc));

                set_aceaddr(&info->tx_ctrl.rngptr, ap->tx_ring_dma);
        }

        info->tx_ctrl.max_len = ACE_TX_RING_ENTRIES(ap);
        tmp = RCB_FLG_TCP_UDP_SUM | RCB_FLG_NO_PSEUDO_HDR | RCB_FLG_VLAN_ASSIST;

        /*
         * The Tigon I does not like having the TX ring in host memory ;-(
         */
        if (!ACE_IS_TIGON_I(ap))
                tmp |= RCB_FLG_TX_HOST_RING;
#if TX_COAL_INTS_ONLY
        tmp |= RCB_FLG_COAL_INT_ONLY;
#endif
        info->tx_ctrl.flags = tmp;

        set_aceaddr(&info->tx_csm_ptr, ap->tx_csm_dma);

        /*
         * Potential item for tuning parameter
         */
#if 0 /* NO */
        writel(DMA_THRESH_16W, &regs->DmaReadCfg);
        writel(DMA_THRESH_16W, &regs->DmaWriteCfg);
#else
        writel(DMA_THRESH_8W, &regs->DmaReadCfg);
        writel(DMA_THRESH_8W, &regs->DmaWriteCfg);
#endif

        writel(0, &regs->MaskInt);
        writel(1, &regs->IfIdx);
#if 0
        /*
         * McKinley boxes do not like us fiddling with AssistState
         * this early
         */
        writel(1, &regs->AssistState);
#endif

        writel(DEF_STAT, &regs->TuneStatTicks);
        writel(DEF_TRACE, &regs->TuneTrace);

        ace_set_rxtx_parms(dev, 0);

        if (board_idx == BOARD_IDX_OVERFLOW) {
                printk(KERN_WARNING "%s: more than %i NICs detected, "
                       "ignoring module parameters!\n",
                       ap->name, ACE_MAX_MOD_PARMS);
        } else if (board_idx >= 0) {
                if (tx_coal_tick[board_idx])
                        writel(tx_coal_tick[board_idx],
                               &regs->TuneTxCoalTicks);
                if (max_tx_desc[board_idx])
                        writel(max_tx_desc[board_idx], &regs->TuneMaxTxDesc);

                if (rx_coal_tick[board_idx])
                        writel(rx_coal_tick[board_idx],
                               &regs->TuneRxCoalTicks);
                if (max_rx_desc[board_idx])
                        writel(max_rx_desc[board_idx], &regs->TuneMaxRxDesc);

                if (trace[board_idx])
                        writel(trace[board_idx], &regs->TuneTrace);

                if ((tx_ratio[board_idx] > 0) && (tx_ratio[board_idx] < 64))
                        writel(tx_ratio[board_idx], &regs->TxBufRat);
        }

        /*
         * Default link parameters
         */
        tmp = LNK_ENABLE | LNK_FULL_DUPLEX | LNK_1000MB | LNK_100MB |
                LNK_10MB | LNK_RX_FLOW_CTL_Y | LNK_NEG_FCTL | LNK_NEGOTIATE;
        if(ap->version >= 2)
                tmp |= LNK_TX_FLOW_CTL_Y;

        /*
         * Override link default parameters
         */
        if ((board_idx >= 0) && link_state[board_idx]) {
                int option = link_state[board_idx];

                tmp = LNK_ENABLE;

                if (option & 0x01) {
                        printk(KERN_INFO "%s: Setting half duplex link\n",
                               ap->name);
                        tmp &= ~LNK_FULL_DUPLEX;
                }
                if (option & 0x02)
                        tmp &= ~LNK_NEGOTIATE;
                if (option & 0x10)
                        tmp |= LNK_10MB;
                if (option & 0x20)
                        tmp |= LNK_100MB;
                if (option & 0x40)
                        tmp |= LNK_1000MB;
                if ((option & 0x70) == 0) {
                        printk(KERN_WARNING "%s: No media speed specified, "
                               "forcing auto negotiation\n", ap->name);
                        tmp |= LNK_NEGOTIATE | LNK_1000MB |
                                LNK_100MB | LNK_10MB;
                }
                if ((option & 0x100) == 0)
                        tmp |= LNK_NEG_FCTL;
                else
                        printk(KERN_INFO "%s: Disabling flow control "
                               "negotiation\n", ap->name);
                if (option & 0x200)
                        tmp |= LNK_RX_FLOW_CTL_Y;
                if ((option & 0x400) && (ap->version >= 2)) {
                        printk(KERN_INFO "%s: Enabling TX flow control\n",
                               ap->name);
                        tmp |= LNK_TX_FLOW_CTL_Y;
                }
        }

        ap->link = tmp;
        writel(tmp, &regs->TuneLink);
        if (ap->version >= 2)
                writel(tmp, &regs->TuneFastLink);

        writel(ap->firmware_start, &regs->Pc);

        writel(0, &regs->Mb0Lo);

        /*
         * Set tx_csm before we start receiving interrupts, otherwise
         * the interrupt handler might think it is supposed to process
         * tx ints before we are up and running, which may cause a null
         * pointer access in the int handler.
         */
        ap->cur_rx = 0;
        ap->tx_prd = *(ap->tx_csm) = ap->tx_ret_csm = 0;

        wmb();
        ace_set_txprd(regs, ap, 0);
        writel(0, &regs->RxRetCsm);

       /*
        * Enable DMA engine now.
        * If we do this sooner, Mckinley box pukes.
        * I assume it's because Tigon II DMA engine wants to check
        * *something* even before the CPU is started.
        */
       writel(1, &regs->AssistState);  /* enable DMA */

        /*
         * Start the NIC CPU
         */
        writel(readl(&regs->CpuCtrl) & ~(CPU_HALT|CPU_TRACE), &regs->CpuCtrl);
        readl(&regs->CpuCtrl);

        /*
         * Wait for the firmware to spin up - max 3 seconds.
         */
        myjif = jiffies + 3 * HZ;
        while (time_before(jiffies, myjif) && !ap->fw_running)
                cpu_relax();

        if (!ap->fw_running) {
                printk(KERN_ERR "%s: Firmware NOT running!\n", ap->name);

                ace_dump_trace(ap);
                writel(readl(&regs->CpuCtrl) | CPU_HALT, &regs->CpuCtrl);
                readl(&regs->CpuCtrl);

                /* aman@sgi.com - account for badly behaving firmware/NIC:
                 * - have observed that the NIC may continue to generate
                 *   interrupts for some reason; attempt to stop it - halt
                 *   second CPU for Tigon II cards, and also clear Mb0
                 * - if we're a module, we'll fail to load if this was
                 *   the only GbE card in the system => if the kernel does
                 *   see an interrupt from the NIC, code to handle it is
                 *   gone and OOps! - so free_irq also
                 */
                if (ap->version >= 2)
                        writel(readl(&regs->CpuBCtrl) | CPU_HALT,
                               &regs->CpuBCtrl);
                writel(0, &regs->Mb0Lo);
                readl(&regs->Mb0Lo);

                ecode = -EBUSY;
                goto init_error;
        }

        /*
         * We load the ring here as there seem to be no way to tell the
         * firmware to wipe the ring without re-initializing it.
         */
        if (!test_and_set_bit(0, &ap->std_refill_busy))
                ace_load_std_rx_ring(dev, RX_RING_SIZE);
        else
                printk(KERN_ERR "%s: Someone is busy refilling the RX ring\n",
                       ap->name);
        if (ap->version >= 2) {
                if (!test_and_set_bit(0, &ap->mini_refill_busy))
                        ace_load_mini_rx_ring(dev, RX_MINI_SIZE);
                else
                        printk(KERN_ERR "%s: Someone is busy refilling "
                               "the RX mini ring\n", ap->name);
        }
        return 0;

 init_error:
        ace_init_cleanup(dev);
        return ecode;
}


static void ace_set_rxtx_parms(struct net_device *dev, int jumbo)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        int board_idx = ap->board_idx;

        if (board_idx >= 0) {
                if (!jumbo) {
                        if (!tx_coal_tick[board_idx])
                                writel(DEF_TX_COAL, &regs->TuneTxCoalTicks);
                        if (!max_tx_desc[board_idx])
                                writel(DEF_TX_MAX_DESC, &regs->TuneMaxTxDesc);
                        if (!rx_coal_tick[board_idx])
                                writel(DEF_RX_COAL, &regs->TuneRxCoalTicks);
                        if (!max_rx_desc[board_idx])
                                writel(DEF_RX_MAX_DESC, &regs->TuneMaxRxDesc);
                        if (!tx_ratio[board_idx])
                                writel(DEF_TX_RATIO, &regs->TxBufRat);
                } else {
                        if (!tx_coal_tick[board_idx])
                                writel(DEF_JUMBO_TX_COAL,
                                       &regs->TuneTxCoalTicks);
                        if (!max_tx_desc[board_idx])
                                writel(DEF_JUMBO_TX_MAX_DESC,
                                       &regs->TuneMaxTxDesc);
                        if (!rx_coal_tick[board_idx])
                                writel(DEF_JUMBO_RX_COAL,
                                       &regs->TuneRxCoalTicks);
                        if (!max_rx_desc[board_idx])
                                writel(DEF_JUMBO_RX_MAX_DESC,
                                       &regs->TuneMaxRxDesc);
                        if (!tx_ratio[board_idx])
                                writel(DEF_JUMBO_TX_RATIO, &regs->TxBufRat);
                }
        }
}


static void ace_watchdog(struct net_device *data)
{
        struct net_device *dev = data;
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;

        /*
         * We haven't received a stats update event for more than 2.5
         * seconds and there is data in the transmit queue, thus we
         * assume the card is stuck.
         */
        if (*ap->tx_csm != ap->tx_ret_csm) {
                printk(KERN_WARNING "%s: Transmitter is stuck, %08x\n",
                       dev->name, (unsigned int)readl(&regs->HostCtrl));
                /* This can happen due to ieee flow control. */
        } else {
                printk(KERN_DEBUG "%s: BUG... transmitter died. Kicking it.\n",
                       dev->name);
#if 0
                netif_wake_queue(dev);
#endif
        }
}


static void ace_tasklet(unsigned long arg)
{
        struct net_device *dev = (struct net_device *) arg;
        struct ace_private *ap = netdev_priv(dev);
        int cur_size;

        cur_size = atomic_read(&ap->cur_rx_bufs);
        if ((cur_size < RX_LOW_STD_THRES) &&
            !test_and_set_bit(0, &ap->std_refill_busy)) {
#ifdef DEBUG
                printk("refilling buffers (current %i)\n", cur_size);
#endif
                ace_load_std_rx_ring(dev, RX_RING_SIZE - cur_size);
        }

        if (ap->version >= 2) {
                cur_size = atomic_read(&ap->cur_mini_bufs);
                if ((cur_size < RX_LOW_MINI_THRES) &&
                    !test_and_set_bit(0, &ap->mini_refill_busy)) {
#ifdef DEBUG
                        printk("refilling mini buffers (current %i)\n",
                               cur_size);
#endif
                        ace_load_mini_rx_ring(dev, RX_MINI_SIZE - cur_size);
                }
        }

        cur_size = atomic_read(&ap->cur_jumbo_bufs);
        if (ap->jumbo && (cur_size < RX_LOW_JUMBO_THRES) &&
            !test_and_set_bit(0, &ap->jumbo_refill_busy)) {
#ifdef DEBUG
                printk("refilling jumbo buffers (current %i)\n", cur_size);
#endif
                ace_load_jumbo_rx_ring(dev, RX_JUMBO_SIZE - cur_size);
        }
        ap->tasklet_pending = 0;
}


/*
 * Copy the contents of the NIC's trace buffer to kernel memory.
 */
static void ace_dump_trace(struct ace_private *ap)
{
#if 0
        if (!ap->trace_buf)
                if (!(ap->trace_buf = kmalloc(ACE_TRACE_SIZE, GFP_KERNEL)))
                    return;
#endif
}


/*
 * Load the standard rx ring.
 *
 * Loading rings is safe without holding the spin lock since this is
 * done only before the device is enabled, thus no interrupts are
 * generated and by the interrupt handler/tasklet handler.
 */
static void ace_load_std_rx_ring(struct net_device *dev, int nr_bufs)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        short i, idx;


        prefetchw(&ap->cur_rx_bufs);

        idx = ap->rx_std_skbprd;

        for (i = 0; i < nr_bufs; i++) {
                struct sk_buff *skb;
                struct rx_desc *rd;
                dma_addr_t mapping;

                skb = netdev_alloc_skb_ip_align(dev, ACE_STD_BUFSIZE);
                if (!skb)
                        break;

                mapping = pci_map_page(ap->pdev, virt_to_page(skb->data),
                                       offset_in_page(skb->data),
                                       ACE_STD_BUFSIZE,
                                       PCI_DMA_FROMDEVICE);
                ap->skb->rx_std_skbuff[idx].skb = skb;
                dma_unmap_addr_set(&ap->skb->rx_std_skbuff[idx],
                                   mapping, mapping);

                rd = &ap->rx_std_ring[idx];
                set_aceaddr(&rd->addr, mapping);
                rd->size = ACE_STD_BUFSIZE;
                rd->idx = idx;
                idx = (idx + 1) % RX_STD_RING_ENTRIES;
        }

        if (!i)
                goto error_out;

        atomic_add(i, &ap->cur_rx_bufs);
        ap->rx_std_skbprd = idx;

        if (ACE_IS_TIGON_I(ap)) {
                struct cmd cmd;
                cmd.evt = C_SET_RX_PRD_IDX;
                cmd.code = 0;
                cmd.idx = ap->rx_std_skbprd;
                ace_issue_cmd(regs, &cmd);
        } else {
                writel(idx, &regs->RxStdPrd);
                wmb();
        }

 out:
        clear_bit(0, &ap->std_refill_busy);
        return;

 error_out:
        printk(KERN_INFO "Out of memory when allocating "
               "standard receive buffers\n");
        goto out;
}


static void ace_load_mini_rx_ring(struct net_device *dev, int nr_bufs)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        short i, idx;

        prefetchw(&ap->cur_mini_bufs);

        idx = ap->rx_mini_skbprd;
        for (i = 0; i < nr_bufs; i++) {
                struct sk_buff *skb;
                struct rx_desc *rd;
                dma_addr_t mapping;

                skb = netdev_alloc_skb_ip_align(dev, ACE_MINI_BUFSIZE);
                if (!skb)
                        break;

                mapping = pci_map_page(ap->pdev, virt_to_page(skb->data),
                                       offset_in_page(skb->data),
                                       ACE_MINI_BUFSIZE,
                                       PCI_DMA_FROMDEVICE);
                ap->skb->rx_mini_skbuff[idx].skb = skb;
                dma_unmap_addr_set(&ap->skb->rx_mini_skbuff[idx],
                                   mapping, mapping);

                rd = &ap->rx_mini_ring[idx];
                set_aceaddr(&rd->addr, mapping);
                rd->size = ACE_MINI_BUFSIZE;
                rd->idx = idx;
                idx = (idx + 1) % RX_MINI_RING_ENTRIES;
        }

        if (!i)
                goto error_out;

        atomic_add(i, &ap->cur_mini_bufs);

        ap->rx_mini_skbprd = idx;

        writel(idx, &regs->RxMiniPrd);
        wmb();

 out:
        clear_bit(0, &ap->mini_refill_busy);
        return;
 error_out:
        printk(KERN_INFO "Out of memory when allocating "
               "mini receive buffers\n");
        goto out;
}


/*
 * Load the jumbo rx ring, this may happen at any time if the MTU
 * is changed to a value > 1500.
 */
static void ace_load_jumbo_rx_ring(struct net_device *dev, int nr_bufs)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        short i, idx;

        idx = ap->rx_jumbo_skbprd;

        for (i = 0; i < nr_bufs; i++) {
                struct sk_buff *skb;
                struct rx_desc *rd;
                dma_addr_t mapping;

                skb = netdev_alloc_skb_ip_align(dev, ACE_JUMBO_BUFSIZE);
                if (!skb)
                        break;

                mapping = pci_map_page(ap->pdev, virt_to_page(skb->data),
                                       offset_in_page(skb->data),
                                       ACE_JUMBO_BUFSIZE,
                                       PCI_DMA_FROMDEVICE);
                ap->skb->rx_jumbo_skbuff[idx].skb = skb;
                dma_unmap_addr_set(&ap->skb->rx_jumbo_skbuff[idx],
                                   mapping, mapping);

                rd = &ap->rx_jumbo_ring[idx];
                set_aceaddr(&rd->addr, mapping);
                rd->size = ACE_JUMBO_BUFSIZE;
                rd->idx = idx;
                idx = (idx + 1) % RX_JUMBO_RING_ENTRIES;
        }

        if (!i)
                goto error_out;

        atomic_add(i, &ap->cur_jumbo_bufs);
        ap->rx_jumbo_skbprd = idx;

        if (ACE_IS_TIGON_I(ap)) {
                struct cmd cmd;
                cmd.evt = C_SET_RX_JUMBO_PRD_IDX;
                cmd.code = 0;
                cmd.idx = ap->rx_jumbo_skbprd;
                ace_issue_cmd(regs, &cmd);
        } else {
                writel(idx, &regs->RxJumboPrd);
                wmb();
        }

 out:
        clear_bit(0, &ap->jumbo_refill_busy);
        return;
 error_out:
        if (net_ratelimit())
                printk(KERN_INFO "Out of memory when allocating "
                       "jumbo receive buffers\n");
        goto out;
}


/*
 * All events are considered to be slow (RX/TX ints do not generate
 * events) and are handled here, outside the main interrupt handler,
 * to reduce the size of the handler.
 */
static u32 ace_handle_event(struct net_device *dev, u32 evtcsm, u32 evtprd)
{
        struct ace_private *ap;

        ap = netdev_priv(dev);

        while (evtcsm != evtprd) {
                switch (ap->evt_ring[evtcsm].evt) {
                case E_FW_RUNNING:
                        printk(KERN_INFO "%s: Firmware up and running\n",
                               ap->name);
                        ap->fw_running = 1;
                        wmb();
                        break;
                case E_STATS_UPDATED:
                        break;
                case E_LNK_STATE:
                {
                        u16 code = ap->evt_ring[evtcsm].code;
                        switch (code) {
                        case E_C_LINK_UP:
                        {
                                u32 state = readl(&ap->regs->GigLnkState);
                                printk(KERN_WARNING "%s: Optical link UP "
                                       "(%s Duplex, Flow Control: %s%s)\n",
                                       ap->name,
                                       state & LNK_FULL_DUPLEX ? "Full":"Half",
                                       state & LNK_TX_FLOW_CTL_Y ? "TX " : "",
                                       state & LNK_RX_FLOW_CTL_Y ? "RX" : "");
                                break;
                        }
                        case E_C_LINK_DOWN:
                                printk(KERN_WARNING "%s: Optical link DOWN\n",
                                       ap->name);
                                break;
                        case E_C_LINK_10_100:
                                printk(KERN_WARNING "%s: 10/100BaseT link "
                                       "UP\n", ap->name);
                                break;
                        default:
                                printk(KERN_ERR "%s: Unknown optical link "
                                       "state %02x\n", ap->name, code);
                        }
                        break;
                }
                case E_ERROR:
                        switch(ap->evt_ring[evtcsm].code) {
                        case E_C_ERR_INVAL_CMD:
                                printk(KERN_ERR "%s: invalid command error\n",
                                       ap->name);
                                break;
                        case E_C_ERR_UNIMP_CMD:
                                printk(KERN_ERR "%s: unimplemented command "
                                       "error\n", ap->name);
                                break;
                        case E_C_ERR_BAD_CFG:
                                printk(KERN_ERR "%s: bad config error\n",
                                       ap->name);
                                break;
                        default:
                                printk(KERN_ERR "%s: unknown error %02x\n",
                                       ap->name, ap->evt_ring[evtcsm].code);
                        }
                        break;
                case E_RESET_JUMBO_RNG:
                {
                        int i;
                        for (i = 0; i < RX_JUMBO_RING_ENTRIES; i++) {
                                if (ap->skb->rx_jumbo_skbuff[i].skb) {
                                        ap->rx_jumbo_ring[i].size = 0;
                                        set_aceaddr(&ap->rx_jumbo_ring[i].addr, 0);
                                        dev_kfree_skb(ap->skb->rx_jumbo_skbuff[i].skb);
                                        ap->skb->rx_jumbo_skbuff[i].skb = NULL;
                                }
                        }

                        if (ACE_IS_TIGON_I(ap)) {
                                struct cmd cmd;
                                cmd.evt = C_SET_RX_JUMBO_PRD_IDX;
                                cmd.code = 0;
                                cmd.idx = 0;
                                ace_issue_cmd(ap->regs, &cmd);
                        } else {
                                writel(0, &((ap->regs)->RxJumboPrd));
                                wmb();
                        }

                        ap->jumbo = 0;
                        ap->rx_jumbo_skbprd = 0;
                        printk(KERN_INFO "%s: Jumbo ring flushed\n",
                               ap->name);
                        clear_bit(0, &ap->jumbo_refill_busy);
                        break;
                }
                default:
                        printk(KERN_ERR "%s: Unhandled event 0x%02x\n",
                               ap->name, ap->evt_ring[evtcsm].evt);
                }
                evtcsm = (evtcsm + 1) % EVT_RING_ENTRIES;
        }

        return evtcsm;
}


static void ace_rx_int(struct net_device *dev, u32 rxretprd, u32 rxretcsm)
{
        struct ace_private *ap = netdev_priv(dev);
        u32 idx;
        int mini_count = 0, std_count = 0;

        idx = rxretcsm;

        prefetchw(&ap->cur_rx_bufs);
        prefetchw(&ap->cur_mini_bufs);

        while (idx != rxretprd) {
                struct ring_info *rip;
                struct sk_buff *skb;
                struct rx_desc *rxdesc, *retdesc;
                u32 skbidx;
                int bd_flags, desc_type, mapsize;
                u16 csum;


                /* make sure the rx descriptor isn't read before rxretprd */
                if (idx == rxretcsm)
                        rmb();

                retdesc = &ap->rx_return_ring[idx];
                skbidx = retdesc->idx;
                bd_flags = retdesc->flags;
                desc_type = bd_flags & (BD_FLG_JUMBO | BD_FLG_MINI);

                switch(desc_type) {
                        /*
                         * Normal frames do not have any flags set
                         *
                         * Mini and normal frames arrive frequently,
                         * so use a local counter to avoid doing
                         * atomic operations for each packet arriving.
                         */
                case 0:
                        rip = &ap->skb->rx_std_skbuff[skbidx];
                        mapsize = ACE_STD_BUFSIZE;
                        rxdesc = &ap->rx_std_ring[skbidx];
                        std_count++;
                        break;
                case BD_FLG_JUMBO:
                        rip = &ap->skb->rx_jumbo_skbuff[skbidx];
                        mapsize = ACE_JUMBO_BUFSIZE;
                        rxdesc = &ap->rx_jumbo_ring[skbidx];
                        atomic_dec(&ap->cur_jumbo_bufs);
                        break;
                case BD_FLG_MINI:
                        rip = &ap->skb->rx_mini_skbuff[skbidx];
                        mapsize = ACE_MINI_BUFSIZE;
                        rxdesc = &ap->rx_mini_ring[skbidx];
                        mini_count++;
                        break;
                default:
                        printk(KERN_INFO "%s: unknown frame type (0x%02x) "
                               "returned by NIC\n", dev->name,
                               retdesc->flags);
                        goto error;
                }

                skb = rip->skb;
                rip->skb = NULL;
                pci_unmap_page(ap->pdev,
                               dma_unmap_addr(rip, mapping),
                               mapsize,
                               PCI_DMA_FROMDEVICE);
                skb_put(skb, retdesc->size);

                /*
                 * Fly baby, fly!
                 */
                csum = retdesc->tcp_udp_csum;

                skb->protocol = eth_type_trans(skb, dev);

                /*
                 * Instead of forcing the poor tigon mips cpu to calculate
                 * pseudo hdr checksum, we do this ourselves.
                 */
                if (bd_flags & BD_FLG_TCP_UDP_SUM) {
                        skb->csum = htons(csum);
                        skb->ip_summed = CHECKSUM_COMPLETE;
                } else {
                        skb_checksum_none_assert(skb);
                }

                /* send it up */
                if ((bd_flags & BD_FLG_VLAN_TAG))
                        __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), retdesc->vlan);
                netif_rx(skb);

                dev->stats.rx_packets++;
                dev->stats.rx_bytes += retdesc->size;

                idx = (idx + 1) % RX_RETURN_RING_ENTRIES;
        }

        atomic_sub(std_count, &ap->cur_rx_bufs);
        if (!ACE_IS_TIGON_I(ap))
                atomic_sub(mini_count, &ap->cur_mini_bufs);

 out:
        /*
         * According to the documentation RxRetCsm is obsolete with
         * the 12.3.x Firmware - my Tigon I NICs seem to disagree!
         */
        if (ACE_IS_TIGON_I(ap)) {
                writel(idx, &ap->regs->RxRetCsm);
        }
        ap->cur_rx = idx;

        return;
 error:
        idx = rxretprd;
        goto out;
}


static inline void ace_tx_int(struct net_device *dev,
                              u32 txcsm, u32 idx)
{
        struct ace_private *ap = netdev_priv(dev);

        do {
                struct sk_buff *skb;
                struct tx_ring_info *info;

                info = ap->skb->tx_skbuff + idx;
                skb = info->skb;

                if (dma_unmap_len(info, maplen)) {
                        pci_unmap_page(ap->pdev, dma_unmap_addr(info, mapping),
                                       dma_unmap_len(info, maplen),
                                       PCI_DMA_TODEVICE);
                        dma_unmap_len_set(info, maplen, 0);
                }

                if (skb) {
                        dev->stats.tx_packets++;
                        dev->stats.tx_bytes += skb->len;
                        dev_kfree_skb_irq(skb);
                        info->skb = NULL;
                }

                idx = (idx + 1) % ACE_TX_RING_ENTRIES(ap);
        } while (idx != txcsm);

        if (netif_queue_stopped(dev))
                netif_wake_queue(dev);

        wmb();
        ap->tx_ret_csm = txcsm;

        /* So... tx_ret_csm is advanced _after_ check for device wakeup.
         *
         * We could try to make it before. In this case we would get
         * the following race condition: hard_start_xmit on other cpu
         * enters after we advanced tx_ret_csm and fills space,
         * which we have just freed, so that we make illegal device wakeup.
         * There is no good way to workaround this (at entry
         * to ace_start_xmit detects this condition and prevents
         * ring corruption, but it is not a good workaround.)
         *
         * When tx_ret_csm is advanced after, we wake up device _only_
         * if we really have some space in ring (though the core doing
         * hard_start_xmit can see full ring for some period and has to
         * synchronize.) Superb.
         * BUT! We get another subtle race condition. hard_start_xmit
         * may think that ring is full between wakeup and advancing
         * tx_ret_csm and will stop device instantly! It is not so bad.
         * We are guaranteed that there is something in ring, so that
         * the next irq will resume transmission. To speedup this we could
         * mark descriptor, which closes ring with BD_FLG_COAL_NOW
         * (see ace_start_xmit).
         *
         * Well, this dilemma exists in all lock-free devices.
         * We, following scheme used in drivers by Donald Becker,
         * select the least dangerous.
         *                                                      --ANK
         */
}


static irqreturn_t ace_interrupt(int irq, void *dev_id)
{
        struct net_device *dev = (struct net_device *)dev_id;
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        u32 idx;
        u32 txcsm, rxretcsm, rxretprd;
        u32 evtcsm, evtprd;

        /*
         * In case of PCI shared interrupts or spurious interrupts,
         * we want to make sure it is actually our interrupt before
         * spending any time in here.
         */
        if (!(readl(&regs->HostCtrl) & IN_INT))
                return IRQ_NONE;

        /*
         * ACK intr now. Otherwise we will lose updates to rx_ret_prd,
         * which happened _after_ rxretprd = *ap->rx_ret_prd; but before
         * writel(0, &regs->Mb0Lo).
         *
         * "IRQ avoidance" recommended in docs applies to IRQs served
         * threads and it is wrong even for that case.
         */
        writel(0, &regs->Mb0Lo);
        readl(&regs->Mb0Lo);

        /*
         * There is no conflict between transmit handling in
         * start_xmit and receive processing, thus there is no reason
         * to take a spin lock for RX handling. Wait until we start
         * working on the other stuff - hey we don't need a spin lock
         * anymore.
         */
        rxretprd = *ap->rx_ret_prd;
        rxretcsm = ap->cur_rx;

        if (rxretprd != rxretcsm)
                ace_rx_int(dev, rxretprd, rxretcsm);

        txcsm = *ap->tx_csm;
        idx = ap->tx_ret_csm;

        if (txcsm != idx) {
                /*
                 * If each skb takes only one descriptor this check degenerates
                 * to identity, because new space has just been opened.
                 * But if skbs are fragmented we must check that this index
                 * update releases enough of space, otherwise we just
                 * wait for device to make more work.
                 */
                if (!tx_ring_full(ap, txcsm, ap->tx_prd))
                        ace_tx_int(dev, txcsm, idx);
        }

        evtcsm = readl(&regs->EvtCsm);
        evtprd = *ap->evt_prd;

        if (evtcsm != evtprd) {
                evtcsm = ace_handle_event(dev, evtcsm, evtprd);
                writel(evtcsm, &regs->EvtCsm);
        }

        /*
         * This has to go last in the interrupt handler and run with
         * the spin lock released ... what lock?
         */
        if (netif_running(dev)) {
                int cur_size;
                int run_tasklet = 0;

                cur_size = atomic_read(&ap->cur_rx_bufs);
                if (cur_size < RX_LOW_STD_THRES) {
                        if ((cur_size < RX_PANIC_STD_THRES) &&
                            !test_and_set_bit(0, &ap->std_refill_busy)) {
#ifdef DEBUG
                                printk("low on std buffers %i\n", cur_size);
#endif
                                ace_load_std_rx_ring(dev,
                                                     RX_RING_SIZE - cur_size);
                        } else
                                run_tasklet = 1;
                }

                if (!ACE_IS_TIGON_I(ap)) {
                        cur_size = atomic_read(&ap->cur_mini_bufs);
                        if (cur_size < RX_LOW_MINI_THRES) {
                                if ((cur_size < RX_PANIC_MINI_THRES) &&
                                    !test_and_set_bit(0,
                                                      &ap->mini_refill_busy)) {
#ifdef DEBUG
                                        printk("low on mini buffers %i\n",
                                               cur_size);
#endif
                                        ace_load_mini_rx_ring(dev,
                                                              RX_MINI_SIZE - cur_size);
                                } else
                                        run_tasklet = 1;
                        }
                }

                if (ap->jumbo) {
                        cur_size = atomic_read(&ap->cur_jumbo_bufs);
                        if (cur_size < RX_LOW_JUMBO_THRES) {
                                if ((cur_size < RX_PANIC_JUMBO_THRES) &&
                                    !test_and_set_bit(0,
                                                      &ap->jumbo_refill_busy)){
#ifdef DEBUG
                                        printk("low on jumbo buffers %i\n",
                                               cur_size);
#endif
                                        ace_load_jumbo_rx_ring(dev,
                                                               RX_JUMBO_SIZE - cur_size);
                                } else
                                        run_tasklet = 1;
                        }
                }
                if (run_tasklet && !ap->tasklet_pending) {
                        ap->tasklet_pending = 1;
                        tasklet_schedule(&ap->ace_tasklet);
                }
        }

        return IRQ_HANDLED;
}

static int ace_open(struct net_device *dev)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        struct cmd cmd;

        if (!(ap->fw_running)) {
                printk(KERN_WARNING "%s: Firmware not running!\n", dev->name);
                return -EBUSY;
        }

        writel(dev->mtu + ETH_HLEN + 4, &regs->IfMtu);

        cmd.evt = C_CLEAR_STATS;
        cmd.code = 0;
        cmd.idx = 0;
        ace_issue_cmd(regs, &cmd);

        cmd.evt = C_HOST_STATE;
        cmd.code = C_C_STACK_UP;
        cmd.idx = 0;
        ace_issue_cmd(regs, &cmd);

        if (ap->jumbo &&
            !test_and_set_bit(0, &ap->jumbo_refill_busy))
                ace_load_jumbo_rx_ring(dev, RX_JUMBO_SIZE);

        if (dev->flags & IFF_PROMISC) {
                cmd.evt = C_SET_PROMISC_MODE;
                cmd.code = C_C_PROMISC_ENABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);

                ap->promisc = 1;
        }else
                ap->promisc = 0;
        ap->mcast_all = 0;

#if 0
        cmd.evt = C_LNK_NEGOTIATION;
        cmd.code = 0;
        cmd.idx = 0;
        ace_issue_cmd(regs, &cmd);
#endif

        netif_start_queue(dev);

        /*
         * Setup the bottom half rx ring refill handler
         */
        tasklet_init(&ap->ace_tasklet, ace_tasklet, (unsigned long)dev);
        return 0;
}


static int ace_close(struct net_device *dev)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        struct cmd cmd;
        unsigned long flags;
        short i;

        /*
         * Without (or before) releasing irq and stopping hardware, this
         * is an absolute non-sense, by the way. It will be reset instantly
         * by the first irq.
         */
        netif_stop_queue(dev);


        if (ap->promisc) {
                cmd.evt = C_SET_PROMISC_MODE;
                cmd.code = C_C_PROMISC_DISABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
                ap->promisc = 0;
        }

        cmd.evt = C_HOST_STATE;
        cmd.code = C_C_STACK_DOWN;
        cmd.idx = 0;
        ace_issue_cmd(regs, &cmd);

        tasklet_kill(&ap->ace_tasklet);

        /*
         * Make sure one CPU is not processing packets while
         * buffers are being released by another.
         */

        local_irq_save(flags);
        ace_mask_irq(dev);

        for (i = 0; i < ACE_TX_RING_ENTRIES(ap); i++) {
                struct sk_buff *skb;
                struct tx_ring_info *info;

                info = ap->skb->tx_skbuff + i;
                skb = info->skb;

                if (dma_unmap_len(info, maplen)) {
                        if (ACE_IS_TIGON_I(ap)) {
                                /* NB: TIGON_1 is special, tx_ring is in io space */
                                struct tx_desc __iomem *tx;
                                tx = (__force struct tx_desc __iomem *) &ap->tx_ring[i];
                                writel(0, &tx->addr.addrhi);
                                writel(0, &tx->addr.addrlo);
                                writel(0, &tx->flagsize);
                        } else
                                memset(ap->tx_ring + i, 0,
                                       sizeof(struct tx_desc));
                        pci_unmap_page(ap->pdev, dma_unmap_addr(info, mapping),
                                       dma_unmap_len(info, maplen),
                                       PCI_DMA_TODEVICE);
                        dma_unmap_len_set(info, maplen, 0);
                }
                if (skb) {
                        dev_kfree_skb(skb);
                        info->skb = NULL;
                }
        }

        if (ap->jumbo) {
                cmd.evt = C_RESET_JUMBO_RNG;
                cmd.code = 0;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
        }

        ace_unmask_irq(dev);
        local_irq_restore(flags);

        return 0;
}


static inline dma_addr_t
ace_map_tx_skb(struct ace_private *ap, struct sk_buff *skb,
               struct sk_buff *tail, u32 idx)
{
        dma_addr_t mapping;
        struct tx_ring_info *info;

        mapping = pci_map_page(ap->pdev, virt_to_page(skb->data),
                               offset_in_page(skb->data),
                               skb->len, PCI_DMA_TODEVICE);

        info = ap->skb->tx_skbuff + idx;
        info->skb = tail;
        dma_unmap_addr_set(info, mapping, mapping);
        dma_unmap_len_set(info, maplen, skb->len);
        return mapping;
}


static inline void
ace_load_tx_bd(struct ace_private *ap, struct tx_desc *desc, u64 addr,
               u32 flagsize, u32 vlan_tag)
{
#if !USE_TX_COAL_NOW
        flagsize &= ~BD_FLG_COAL_NOW;
#endif

        if (ACE_IS_TIGON_I(ap)) {
                struct tx_desc __iomem *io = (__force struct tx_desc __iomem *) desc;
                writel(addr >> 32, &io->addr.addrhi);
                writel(addr & 0xffffffff, &io->addr.addrlo);
                writel(flagsize, &io->flagsize);
                writel(vlan_tag, &io->vlanres);
        } else {
                desc->addr.addrhi = addr >> 32;
                desc->addr.addrlo = addr;
                desc->flagsize = flagsize;
                desc->vlanres = vlan_tag;
        }
}


static netdev_tx_t ace_start_xmit(struct sk_buff *skb,
                                  struct net_device *dev)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        struct tx_desc *desc;
        u32 idx, flagsize;
        unsigned long maxjiff = jiffies + 3*HZ;

restart:
        idx = ap->tx_prd;

        if (tx_ring_full(ap, ap->tx_ret_csm, idx))
                goto overflow;

        if (!skb_shinfo(skb)->nr_frags) {
                dma_addr_t mapping;
                u32 vlan_tag = 0;

                mapping = ace_map_tx_skb(ap, skb, skb, idx);
                flagsize = (skb->len << 16) | (BD_FLG_END);
                if (skb->ip_summed == CHECKSUM_PARTIAL)
                        flagsize |= BD_FLG_TCP_UDP_SUM;
                if (skb_vlan_tag_present(skb)) {
                        flagsize |= BD_FLG_VLAN_TAG;
                        vlan_tag = skb_vlan_tag_get(skb);
                }
                desc = ap->tx_ring + idx;
                idx = (idx + 1) % ACE_TX_RING_ENTRIES(ap);

                /* Look at ace_tx_int for explanations. */
                if (tx_ring_full(ap, ap->tx_ret_csm, idx))
                        flagsize |= BD_FLG_COAL_NOW;

                ace_load_tx_bd(ap, desc, mapping, flagsize, vlan_tag);
        } else {
                dma_addr_t mapping;
                u32 vlan_tag = 0;
                int i, len = 0;

                mapping = ace_map_tx_skb(ap, skb, NULL, idx);
                flagsize = (skb_headlen(skb) << 16);
                if (skb->ip_summed == CHECKSUM_PARTIAL)
                        flagsize |= BD_FLG_TCP_UDP_SUM;
                if (skb_vlan_tag_present(skb)) {
                        flagsize |= BD_FLG_VLAN_TAG;
                        vlan_tag = skb_vlan_tag_get(skb);
                }

                ace_load_tx_bd(ap, ap->tx_ring + idx, mapping, flagsize, vlan_tag);

                idx = (idx + 1) % ACE_TX_RING_ENTRIES(ap);

                for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
                        const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                        struct tx_ring_info *info;

                        len += skb_frag_size(frag);
                        info = ap->skb->tx_skbuff + idx;
                        desc = ap->tx_ring + idx;

                        mapping = skb_frag_dma_map(&ap->pdev->dev, frag, 0,
                                                   skb_frag_size(frag),
                                                   DMA_TO_DEVICE);

                        flagsize = skb_frag_size(frag) << 16;
                        if (skb->ip_summed == CHECKSUM_PARTIAL)
                                flagsize |= BD_FLG_TCP_UDP_SUM;
                        idx = (idx + 1) % ACE_TX_RING_ENTRIES(ap);

                        if (i == skb_shinfo(skb)->nr_frags - 1) {
                                flagsize |= BD_FLG_END;
                                if (tx_ring_full(ap, ap->tx_ret_csm, idx))
                                        flagsize |= BD_FLG_COAL_NOW;

                                /*
                                 * Only the last fragment frees
                                 * the skb!
                                 */
                                info->skb = skb;
                        } else {
                                info->skb = NULL;
                        }
                        dma_unmap_addr_set(info, mapping, mapping);
                        dma_unmap_len_set(info, maplen, skb_frag_size(frag));
                        ace_load_tx_bd(ap, desc, mapping, flagsize, vlan_tag);
                }
        }

        wmb();
        ap->tx_prd = idx;
        ace_set_txprd(regs, ap, idx);

        if (flagsize & BD_FLG_COAL_NOW) {
                netif_stop_queue(dev);

                /*
                 * A TX-descriptor producer (an IRQ) might have gotten
                 * between, making the ring free again. Since xmit is
                 * serialized, this is the only situation we have to
                 * re-test.
                 */
                if (!tx_ring_full(ap, ap->tx_ret_csm, idx))
                        netif_wake_queue(dev);
        }

        return NETDEV_TX_OK;

overflow:
        /*
         * This race condition is unavoidable with lock-free drivers.
         * We wake up the queue _before_ tx_prd is advanced, so that we can
         * enter hard_start_xmit too early, while tx ring still looks closed.
         * This happens ~1-4 times per 100000 packets, so that we can allow
         * to loop syncing to other CPU. Probably, we need an additional
         * wmb() in ace_tx_intr as well.
         *
         * Note that this race is relieved by reserving one more entry
         * in tx ring than it is necessary (see original non-SG driver).
         * However, with SG we need to reserve 2*MAX_SKB_FRAGS+1, which
         * is already overkill.
         *
         * Alternative is to return with 1 not throttling queue. In this
         * case loop becomes longer, no more useful effects.
         */
        if (time_before(jiffies, maxjiff)) {
                barrier();
                cpu_relax();
                goto restart;
        }

        /* The ring is stuck full. */
        printk(KERN_WARNING "%s: Transmit ring stuck full\n", dev->name);
        return NETDEV_TX_BUSY;
}


static int ace_change_mtu(struct net_device *dev, int new_mtu)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;

        writel(new_mtu + ETH_HLEN + 4, &regs->IfMtu);
        dev->mtu = new_mtu;

        if (new_mtu > ACE_STD_MTU) {
                if (!(ap->jumbo)) {
                        printk(KERN_INFO "%s: Enabling Jumbo frame "
                               "support\n", dev->name);
                        ap->jumbo = 1;
                        if (!test_and_set_bit(0, &ap->jumbo_refill_busy))
                                ace_load_jumbo_rx_ring(dev, RX_JUMBO_SIZE);
                        ace_set_rxtx_parms(dev, 1);
                }
        } else {
                while (test_and_set_bit(0, &ap->jumbo_refill_busy));
                ace_sync_irq(dev->irq);
                ace_set_rxtx_parms(dev, 0);
                if (ap->jumbo) {
                        struct cmd cmd;

                        cmd.evt = C_RESET_JUMBO_RNG;
                        cmd.code = 0;
                        cmd.idx = 0;
                        ace_issue_cmd(regs, &cmd);
                }
        }

        return 0;
}

static int ace_get_settings(struct net_device *dev, struct ethtool_cmd *ecmd)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        u32 link;

        memset(ecmd, 0, sizeof(struct ethtool_cmd));
        ecmd->supported =
                (SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full |
                 SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full |
                 SUPPORTED_1000baseT_Half | SUPPORTED_1000baseT_Full |
                 SUPPORTED_Autoneg | SUPPORTED_FIBRE);

        ecmd->port = PORT_FIBRE;
        ecmd->transceiver = XCVR_INTERNAL;

        link = readl(&regs->GigLnkState);
        if (link & LNK_1000MB)
                ethtool_cmd_speed_set(ecmd, SPEED_1000);
        else {
                link = readl(&regs->FastLnkState);
                if (link & LNK_100MB)
                        ethtool_cmd_speed_set(ecmd, SPEED_100);
                else if (link & LNK_10MB)
                        ethtool_cmd_speed_set(ecmd, SPEED_10);
                else
                        ethtool_cmd_speed_set(ecmd, 0);
        }
        if (link & LNK_FULL_DUPLEX)
                ecmd->duplex = DUPLEX_FULL;
        else
                ecmd->duplex = DUPLEX_HALF;

        if (link & LNK_NEGOTIATE)
                ecmd->autoneg = AUTONEG_ENABLE;
        else
                ecmd->autoneg = AUTONEG_DISABLE;

#if 0
        /*
         * Current struct ethtool_cmd is insufficient
         */
        ecmd->trace = readl(&regs->TuneTrace);

        ecmd->txcoal = readl(&regs->TuneTxCoalTicks);
        ecmd->rxcoal = readl(&regs->TuneRxCoalTicks);
#endif
        ecmd->maxtxpkt = readl(&regs->TuneMaxTxDesc);
        ecmd->maxrxpkt = readl(&regs->TuneMaxRxDesc);

        return 0;
}

static int ace_set_settings(struct net_device *dev, struct ethtool_cmd *ecmd)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        u32 link, speed;

        link = readl(&regs->GigLnkState);
        if (link & LNK_1000MB)
                speed = SPEED_1000;
        else {
                link = readl(&regs->FastLnkState);
                if (link & LNK_100MB)
                        speed = SPEED_100;
                else if (link & LNK_10MB)
                        speed = SPEED_10;
                else
                        speed = SPEED_100;
        }

        link = LNK_ENABLE | LNK_1000MB | LNK_100MB | LNK_10MB |
                LNK_RX_FLOW_CTL_Y | LNK_NEG_FCTL;
        if (!ACE_IS_TIGON_I(ap))
                link |= LNK_TX_FLOW_CTL_Y;
        if (ecmd->autoneg == AUTONEG_ENABLE)
                link |= LNK_NEGOTIATE;
        if (ethtool_cmd_speed(ecmd) != speed) {
                link &= ~(LNK_1000MB | LNK_100MB | LNK_10MB);
                switch (ethtool_cmd_speed(ecmd)) {
                case SPEED_1000:
                        link |= LNK_1000MB;
                        break;
                case SPEED_100:
                        link |= LNK_100MB;
                        break;
                case SPEED_10:
                        link |= LNK_10MB;
                        break;
                }
        }

        if (ecmd->duplex == DUPLEX_FULL)
                link |= LNK_FULL_DUPLEX;

        if (link != ap->link) {
                struct cmd cmd;
                printk(KERN_INFO "%s: Renegotiating link state\n",
                       dev->name);

                ap->link = link;
                writel(link, &regs->TuneLink);
                if (!ACE_IS_TIGON_I(ap))
                        writel(link, &regs->TuneFastLink);
                wmb();

                cmd.evt = C_LNK_NEGOTIATION;
                cmd.code = 0;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
        }
        return 0;
}

static void ace_get_drvinfo(struct net_device *dev,
                            struct ethtool_drvinfo *info)
{
        struct ace_private *ap = netdev_priv(dev);

        strlcpy(info->driver, "acenic", sizeof(info->driver));
        snprintf(info->version, sizeof(info->version), "%i.%i.%i",
                 ap->firmware_major, ap->firmware_minor,
                 ap->firmware_fix);

        if (ap->pdev)
                strlcpy(info->bus_info, pci_name(ap->pdev),
                        sizeof(info->bus_info));

}

/*
 * Set the hardware MAC address.
 */
static int ace_set_mac_addr(struct net_device *dev, void *p)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        struct sockaddr *addr=p;
        u8 *da;
        struct cmd cmd;

        if(netif_running(dev))
                return -EBUSY;

        memcpy(dev->dev_addr, addr->sa_data,dev->addr_len);

        da = (u8 *)dev->dev_addr;

        writel(da[0] << 8 | da[1], &regs->MacAddrHi);
        writel((da[2] << 24) | (da[3] << 16) | (da[4] << 8) | da[5],
               &regs->MacAddrLo);

        cmd.evt = C_SET_MAC_ADDR;
        cmd.code = 0;
        cmd.idx = 0;
        ace_issue_cmd(regs, &cmd);

        return 0;
}


static void ace_set_multicast_list(struct net_device *dev)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        struct cmd cmd;

        if ((dev->flags & IFF_ALLMULTI) && !(ap->mcast_all)) {
                cmd.evt = C_SET_MULTICAST_MODE;
                cmd.code = C_C_MCAST_ENABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
                ap->mcast_all = 1;
        } else if (ap->mcast_all) {
                cmd.evt = C_SET_MULTICAST_MODE;
                cmd.code = C_C_MCAST_DISABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
                ap->mcast_all = 0;
        }

        if ((dev->flags & IFF_PROMISC) && !(ap->promisc)) {
                cmd.evt = C_SET_PROMISC_MODE;
                cmd.code = C_C_PROMISC_ENABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
                ap->promisc = 1;
        }else if (!(dev->flags & IFF_PROMISC) && (ap->promisc)) {
                cmd.evt = C_SET_PROMISC_MODE;
                cmd.code = C_C_PROMISC_DISABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
                ap->promisc = 0;
        }

        /*
         * For the time being multicast relies on the upper layers
         * filtering it properly. The Firmware does not allow one to
         * set the entire multicast list at a time and keeping track of
         * it here is going to be messy.
         */
        if (!netdev_mc_empty(dev) && !ap->mcast_all) {
                cmd.evt = C_SET_MULTICAST_MODE;
                cmd.code = C_C_MCAST_ENABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
        }else if (!ap->mcast_all) {
                cmd.evt = C_SET_MULTICAST_MODE;
                cmd.code = C_C_MCAST_DISABLE;
                cmd.idx = 0;
                ace_issue_cmd(regs, &cmd);
        }
}


static struct net_device_stats *ace_get_stats(struct net_device *dev)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_mac_stats __iomem *mac_stats =
                (struct ace_mac_stats __iomem *)ap->regs->Stats;

        dev->stats.rx_missed_errors = readl(&mac_stats->drop_space);
        dev->stats.multicast = readl(&mac_stats->kept_mc);
        dev->stats.collisions = readl(&mac_stats->coll);

        return &dev->stats;
}


static void ace_copy(struct ace_regs __iomem *regs, const __be32 *src,
                     u32 dest, int size)
{
        void __iomem *tdest;
        short tsize, i;

        if (size <= 0)
                return;

        while (size > 0) {
                tsize = min_t(u32, ((~dest & (ACE_WINDOW_SIZE - 1)) + 1),
                            min_t(u32, size, ACE_WINDOW_SIZE));
                tdest = (void __iomem *) &regs->Window +
                        (dest & (ACE_WINDOW_SIZE - 1));
                writel(dest & ~(ACE_WINDOW_SIZE - 1), &regs->WinBase);
                for (i = 0; i < (tsize / 4); i++) {
                        /* Firmware is big-endian */
                        writel(be32_to_cpup(src), tdest);
                        src++;
                        tdest += 4;
                        dest += 4;
                        size -= 4;
                }
        }
}


static void ace_clear(struct ace_regs __iomem *regs, u32 dest, int size)
{
        void __iomem *tdest;
        short tsize = 0, i;

        if (size <= 0)
                return;

        while (size > 0) {
                tsize = min_t(u32, ((~dest & (ACE_WINDOW_SIZE - 1)) + 1),
                                min_t(u32, size, ACE_WINDOW_SIZE));
                tdest = (void __iomem *) &regs->Window +
                        (dest & (ACE_WINDOW_SIZE - 1));
                writel(dest & ~(ACE_WINDOW_SIZE - 1), &regs->WinBase);

                for (i = 0; i < (tsize / 4); i++) {
                        writel(0, tdest + i*4);
                }

                dest += tsize;
                size -= tsize;
        }
}


/*
 * Download the firmware into the SRAM on the NIC
 *
 * This operation requires the NIC to be halted and is performed with
 * interrupts disabled and with the spinlock hold.
 */
static int ace_load_firmware(struct net_device *dev)
{
        const struct firmware *fw;
        const char *fw_name = "acenic/tg2.bin";
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        const __be32 *fw_data;
        u32 load_addr;
        int ret;

        if (!(readl(&regs->CpuCtrl) & CPU_HALTED)) {
                printk(KERN_ERR "%s: trying to download firmware while the "
                       "CPU is running!\n", ap->name);
                return -EFAULT;
        }

        if (ACE_IS_TIGON_I(ap))
                fw_name = "acenic/tg1.bin";

        ret = request_firmware(&fw, fw_name, &ap->pdev->dev);
        if (ret) {
                printk(KERN_ERR "%s: Failed to load firmware \"%s\"\n",
                       ap->name, fw_name);
                return ret;
        }

        fw_data = (void *)fw->data;

        /* Firmware blob starts with version numbers, followed by
           load and start address. Remainder is the blob to be loaded
           contiguously from load address. We don't bother to represent
           the BSS/SBSS sections any more, since we were clearing the
           whole thing anyway. */
        ap->firmware_major = fw->data[0];
        ap->firmware_minor = fw->data[1];
        ap->firmware_fix = fw->data[2];

        ap->firmware_start = be32_to_cpu(fw_data[1]);
        if (ap->firmware_start < 0x4000 || ap->firmware_start >= 0x80000) {
                printk(KERN_ERR "%s: bogus load address %08x in \"%s\"\n",
                       ap->name, ap->firmware_start, fw_name);
                ret = -EINVAL;
                goto out;
        }

        load_addr = be32_to_cpu(fw_data[2]);
        if (load_addr < 0x4000 || load_addr >= 0x80000) {
                printk(KERN_ERR "%s: bogus load address %08x in \"%s\"\n",
                       ap->name, load_addr, fw_name);
                ret = -EINVAL;
                goto out;
        }

        /*
         * Do not try to clear more than 512KiB or we end up seeing
         * funny things on NICs with only 512KiB SRAM
         */
        ace_clear(regs, 0x2000, 0x80000-0x2000);
        ace_copy(regs, &fw_data[3], load_addr, fw->size-12);
 out:
        release_firmware(fw);
        return ret;
}


/*
 * The eeprom on the AceNIC is an Atmel i2c EEPROM.
 *
 * Accessing the EEPROM is `interesting' to say the least - don't read
 * this code right after dinner.
 *
 * This is all about black magic and bit-banging the device .... I
 * wonder in what hospital they have put the guy who designed the i2c
 * specs.
 *
 * Oh yes, this is only the beginning!
 *
 * Thanks to Stevarino Webinski for helping tracking down the bugs in the
 * code i2c readout code by beta testing all my hacks.
 */
static void eeprom_start(struct ace_regs __iomem *regs)
{
        u32 local;

        readl(&regs->LocalCtrl);
        udelay(ACE_SHORT_DELAY);
        local = readl(&regs->LocalCtrl);
        local |= EEPROM_DATA_OUT | EEPROM_WRITE_ENABLE;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        local |= EEPROM_CLK_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        local &= ~EEPROM_DATA_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        local &= ~EEPROM_CLK_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
}


static void eeprom_prep(struct ace_regs __iomem *regs, u8 magic)
{
        short i;
        u32 local;

        udelay(ACE_SHORT_DELAY);
        local = readl(&regs->LocalCtrl);
        local &= ~EEPROM_DATA_OUT;
        local |= EEPROM_WRITE_ENABLE;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();

        for (i = 0; i < 8; i++, magic <<= 1) {
                udelay(ACE_SHORT_DELAY);
                if (magic & 0x80)
                        local |= EEPROM_DATA_OUT;
                else
                        local &= ~EEPROM_DATA_OUT;
                writel(local, &regs->LocalCtrl);
                readl(&regs->LocalCtrl);
                mb();

                udelay(ACE_SHORT_DELAY);
                local |= EEPROM_CLK_OUT;
                writel(local, &regs->LocalCtrl);
                readl(&regs->LocalCtrl);
                mb();
                udelay(ACE_SHORT_DELAY);
                local &= ~(EEPROM_CLK_OUT | EEPROM_DATA_OUT);
                writel(local, &regs->LocalCtrl);
                readl(&regs->LocalCtrl);
                mb();
        }
}


static int eeprom_check_ack(struct ace_regs __iomem *regs)
{
        int state;
        u32 local;

        local = readl(&regs->LocalCtrl);
        local &= ~EEPROM_WRITE_ENABLE;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_LONG_DELAY);
        local |= EEPROM_CLK_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        /* sample data in middle of high clk */
        state = (readl(&regs->LocalCtrl) & EEPROM_DATA_IN) != 0;
        udelay(ACE_SHORT_DELAY);
        mb();
        writel(readl(&regs->LocalCtrl) & ~EEPROM_CLK_OUT, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();

        return state;
}


static void eeprom_stop(struct ace_regs __iomem *regs)
{
        u32 local;

        udelay(ACE_SHORT_DELAY);
        local = readl(&regs->LocalCtrl);
        local |= EEPROM_WRITE_ENABLE;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        local &= ~EEPROM_DATA_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        local |= EEPROM_CLK_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        local |= EEPROM_DATA_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_LONG_DELAY);
        local &= ~EEPROM_CLK_OUT;
        writel(local, &regs->LocalCtrl);
        mb();
}


/*
 * Read a whole byte from the EEPROM.
 */
static int read_eeprom_byte(struct net_device *dev, unsigned long offset)
{
        struct ace_private *ap = netdev_priv(dev);
        struct ace_regs __iomem *regs = ap->regs;
        unsigned long flags;
        u32 local;
        int result = 0;
        short i;

        /*
         * Don't take interrupts on this CPU will bit banging
         * the %#%#@$ I2C device
         */
        local_irq_save(flags);

        eeprom_start(regs);

        eeprom_prep(regs, EEPROM_WRITE_SELECT);
        if (eeprom_check_ack(regs)) {
                local_irq_restore(flags);
                printk(KERN_ERR "%s: Unable to sync eeprom\n", ap->name);
                result = -EIO;
                goto eeprom_read_error;
        }

        eeprom_prep(regs, (offset >> 8) & 0xff);
        if (eeprom_check_ack(regs)) {
                local_irq_restore(flags);
                printk(KERN_ERR "%s: Unable to set address byte 0\n",
                       ap->name);
                result = -EIO;
                goto eeprom_read_error;
        }

        eeprom_prep(regs, offset & 0xff);
        if (eeprom_check_ack(regs)) {
                local_irq_restore(flags);
                printk(KERN_ERR "%s: Unable to set address byte 1\n",
                       ap->name);
                result = -EIO;
                goto eeprom_read_error;
        }

        eeprom_start(regs);
        eeprom_prep(regs, EEPROM_READ_SELECT);
        if (eeprom_check_ack(regs)) {
                local_irq_restore(flags);
                printk(KERN_ERR "%s: Unable to set READ_SELECT\n",
                       ap->name);
                result = -EIO;
                goto eeprom_read_error;
        }

        for (i = 0; i < 8; i++) {
                local = readl(&regs->LocalCtrl);
                local &= ~EEPROM_WRITE_ENABLE;
                writel(local, &regs->LocalCtrl);
                readl(&regs->LocalCtrl);
                udelay(ACE_LONG_DELAY);
                mb();
                local |= EEPROM_CLK_OUT;
                writel(local, &regs->LocalCtrl);
                readl(&regs->LocalCtrl);
                mb();
                udelay(ACE_SHORT_DELAY);
                /* sample data mid high clk */
                result = (result << 1) |
                        ((readl(&regs->LocalCtrl) & EEPROM_DATA_IN) != 0);
                udelay(ACE_SHORT_DELAY);
                mb();
                local = readl(&regs->LocalCtrl);
                local &= ~EEPROM_CLK_OUT;
                writel(local, &regs->LocalCtrl);
                readl(&regs->LocalCtrl);
                udelay(ACE_SHORT_DELAY);
                mb();
                if (i == 7) {
                        local |= EEPROM_WRITE_ENABLE;
                        writel(local, &regs->LocalCtrl);
                        readl(&regs->LocalCtrl);
                        mb();
                        udelay(ACE_SHORT_DELAY);
                }
        }

        local |= EEPROM_DATA_OUT;
        writel(local, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        writel(readl(&regs->LocalCtrl) | EEPROM_CLK_OUT, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        udelay(ACE_LONG_DELAY);
        writel(readl(&regs->LocalCtrl) & ~EEPROM_CLK_OUT, &regs->LocalCtrl);
        readl(&regs->LocalCtrl);
        mb();
        udelay(ACE_SHORT_DELAY);
        eeprom_stop(regs);

        local_irq_restore(flags);
 out:
        return result;

 eeprom_read_error:
        printk(KERN_ERR "%s: Unable to read eeprom byte 0x%02lx\n",
               ap->name, offset);
        goto out;
}

module_pci_driver(acenic_pci_driver);