* add p cc

[mascara-docs.git] / i386 / linux / linux-2.3.21 / drivers / net / defxx.c

/*
 * File Name:
 *   defxx.c
 *
 * Copyright Information:
 *   Copyright Digital Equipment Corporation 1996.
 *
 *   This software may be used and distributed according to the terms of
 *   the GNU Public License, incorporated herein by reference.
 *
 * Abstract:
 *   A Linux device driver supporting the Digital Equipment Corporation
 *   FDDI EISA and PCI controller families.  Supported adapters include:
 *
 *              DEC FDDIcontroller/EISA (DEFEA)
 *              DEC FDDIcontroller/PCI  (DEFPA)
 *
 * Maintainers:
 *   LVS        Lawrence V. Stefani
 *
 * Contact:
 *       The author may be reached at:
 *
 *              Inet: stefani@lkg.dec.com
 *              Mail: Digital Equipment Corporation
 *                        550 King Street
 *                        M/S: LKG1-3/M07
 *                        Littleton, MA  01460
 *
 * Credits:
 *   I'd like to thank Patricia Cross for helping me get started with
 *   Linux, David Davies for a lot of help upgrading and configuring
 *   my development system and for answering many OS and driver
 *   development questions, and Alan Cox for recommendations and
 *   integration help on getting FDDI support into Linux.  LVS
 *
 * Driver Architecture:
 *   The driver architecture is largely based on previous driver work
 *   for other operating systems.  The upper edge interface and
 *   functions were largely taken from existing Linux device drivers
 *   such as David Davies' DE4X5.C driver and Donald Becker's TULIP.C
 *   driver.
 *
 *   Adapter Probe -
 *              The driver scans for supported EISA adapters by reading the
 *              SLOT ID register for each EISA slot and making a match
 *              against the expected value.  The supported PCI adapters are
 *              discovered using successive calls to pcibios_find_device.
 *              The first time the probe routine is called, all supported
 *              devices are discovered and initialized.  The adapters aren't
 *              brought up to an operational state until the open routine is
 *              called.
 *
 *   Bus-Specific Initialization -
 *              This driver currently supports both EISA and PCI controller
 *              families.  While the custom DMA chip and FDDI logic is similar
 *              or identical, the bus logic is very different.  After
 *              initialization, the     only bus-specific differences is in how the
 *              driver enables and disables interrupts.  Other than that, the
 *              run-time critical code behaves the same on both families.
 *              It's important to note that both adapter families are configured
 *              to I/O map, rather than memory map, the adapter registers.
 *
 *   Driver Open/Close -
 *              In the driver open routine, the driver ISR (interrupt service
 *              routine) is registered and the adapter is brought to an
 *              operational state.  In the driver close routine, the opposite
 *              occurs; the driver ISR is deregistered and the adapter is
 *              brought to a safe, but closed state.  Users may use consecutive
 *              commands to bring the adapter up and down as in the following
 *              example:
 *                                      ifconfig fddi0 up
 *                                      ifconfig fddi0 down
 *                                      ifconfig fddi0 up
 *
 *   Driver Shutdown -
 *              Apparently, there is no shutdown or halt routine support under
 *              Linux.  This routine would be called during "reboot" or
 *              "shutdown" to allow the driver to place the adapter in a safe
 *              state before a warm reboot occurs.  To be really safe, the user
 *              should close the adapter before shutdown (eg. ifconfig fddi0 down)
 *              to ensure that the adapter DMA engine is taken off-line.  However,
 *              the current driver code anticipates this problem and always issues
 *              a soft reset of the adapter     at the beginning of driver initialization.
 *              A future driver enhancement in this area may occur in 2.1.X where
 *              Alan indicated that a shutdown handler may be implemented.
 *
 *   Interrupt Service Routine -
 *              The driver supports shared interrupts, so the ISR is registered for
 *              each board with the appropriate flag and the pointer to that board's
 *              device structure.  This provides the context during interrupt
 *              processing to support shared interrupts and multiple boards.
 *
 *              Interrupt enabling/disabling can occur at many levels.  At the host
 *              end, you can disable system interrupts, or disable interrupts at the
 *              PIC (on Intel systems).  Across the bus, both EISA and PCI adapters
 *              have a bus-logic chip interrupt enable/disable as well as a DMA
 *              controller interrupt enable/disable.
 *
 *              The driver currently enables and disables adapter interrupts at the
 *              bus-logic chip and assumes that Linux will take care of clearing or
 *              acknowledging any host-based interrupt chips.
 *
 *   Control Functions -
 *              Control functions are those used to support functions such as adding
 *              or deleting multicast addresses, enabling or disabling packet
 *              reception filters, or other custom/proprietary commands.  Presently,
 *              the driver supports the "get statistics", "set multicast list", and
 *              "set mac address" functions defined by Linux.  A list of possible
 *              enhancements include:
 *
 *                              - Custom ioctl interface for executing port interface commands
 *                              - Custom ioctl interface for adding unicast addresses to
 *                                adapter CAM (to support bridge functions).
 *                              - Custom ioctl interface for supporting firmware upgrades.
 *
 *   Hardware (port interface) Support Routines -
 *              The driver function names that start with "dfx_hw_" represent
 *              low-level port interface routines that are called frequently.  They
 *              include issuing a DMA or port control command to the adapter,
 *              resetting the adapter, or reading the adapter state.  Since the
 *              driver initialization and run-time code must make calls into the
 *              port interface, these routines were written to be as generic and
 *              usable as possible.
 *
 *   Receive Path -
 *              The adapter DMA engine supports a 256 entry receive descriptor block
 *              of which up to 255 entries can be used at any given time.  The
 *              architecture is a standard producer, consumer, completion model in
 *              which the driver "produces" receive buffers to the adapter, the
 *              adapter "consumes" the receive buffers by DMAing incoming packet data,
 *              and the driver "completes" the receive buffers by servicing the
 *              incoming packet, then "produces" a new buffer and starts the cycle
 *              again.  Receive buffers can be fragmented in up to 16 fragments
 *              (descriptor     entries).  For simplicity, this driver posts
 *              single-fragment receive buffers of 4608 bytes, then allocates a
 *              sk_buff, copies the data, then reposts the buffer.  To reduce CPU
 *              utilization, a better approach would be to pass up the receive
 *              buffer (no extra copy) then allocate and post a replacement buffer.
 *              This is a performance enhancement that should be looked into at
 *              some point.
 *
 *   Transmit Path -
 *              Like the receive path, the adapter DMA engine supports a 256 entry
 *              transmit descriptor block of which up to 255 entries can be used at
 *              any     given time.  Transmit buffers can be fragmented in up to 255
 *              fragments (descriptor entries).  This driver always posts one
 *              fragment per transmit packet request.
 *
 *              The fragment contains the entire packet from FC to end of data.
 *              Before posting the buffer to the adapter, the driver sets a three-byte
 *              packet request header (PRH) which is required by the Motorola MAC chip
 *              used on the adapters.  The PRH tells the MAC the type of token to
 *              receive/send, whether or not to generate and append the CRC, whether
 *              synchronous or asynchronous framing is used, etc.  Since the PRH
 *              definition is not necessarily consistent across all FDDI chipsets,
 *              the driver, rather than the common FDDI packet handler routines,
 *              sets these bytes.
 *
 *              To reduce the amount of descriptor fetches needed per transmit request,
 *              the driver takes advantage of the fact that there are at least three
 *              bytes available before the skb->data field on the outgoing transmit
 *              request.  This is guaranteed by having fddi_setup() in net_init.c set
 *              dev->hard_header_len to 24 bytes.  21 bytes accounts for the largest
 *              header in an 802.2 SNAP frame.  The other 3 bytes are the extra "pad"
 *              bytes which we'll use to store the PRH.
 *
 *              There's a subtle advantage to adding these pad bytes to the
 *              hard_header_len, it ensures that the data portion of the packet for
 *              an 802.2 SNAP frame is longword aligned.  Other FDDI driver
 *              implementations may not need the extra padding and can start copying
 *              or DMAing directly from the FC byte which starts at skb->data.  Should
 *              another driver implementation need ADDITIONAL padding, the net_init.c
 *              module should be updated and dev->hard_header_len should be increased.
 *              NOTE: To maintain the alignment on the data portion of the packet,
 *              dev->hard_header_len should always be evenly divisible by 4 and at
 *              least 24 bytes in size.
 *
 * Modification History:
 *              Date            Name    Description
 *              16-Aug-96       LVS             Created.
 *              20-Aug-96       LVS             Updated dfx_probe so that version information
 *                                                      string is only displayed if 1 or more cards are
 *                                                      found.  Changed dfx_rcv_queue_process to copy
 *                                                      3 NULL bytes before FC to ensure that data is
 *                                                      longword aligned in receive buffer.
 *              09-Sep-96       LVS             Updated dfx_ctl_set_multicast_list to enable
 *                                                      LLC group promiscuous mode if multicast list
 *                                                      is too large.  LLC individual/group promiscuous
 *                                                      mode is now disabled if IFF_PROMISC flag not set.
 *                                                      dfx_xmt_queue_pkt no longer checks for NULL skb
 *                                                      on Alan Cox recommendation.  Added node address
 *                                                      override support.
 *              12-Sep-96       LVS             Reset current address to factory address during
 *                                                      device open.  Updated transmit path to post a
 *                                                      single fragment which includes PRH->end of data.
 */

/* Version information string - should be updated prior to each new release!!! */

static const char *version = "defxx.c:v1.04 09/16/96  Lawrence V. Stefani (stefani@lkg.dec.com)\n";

/* Include files */

#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/malloc.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <asm/byteorder.h>
#include <asm/bitops.h>
#include <asm/io.h>

#include <linux/netdevice.h>
#include <linux/fddidevice.h>
#include <linux/skbuff.h>

#include "defxx.h"

#define DYNAMIC_BUFFERS 1

#define SKBUFF_RX_COPYBREAK 200
/*
 * NEW_SKB_SIZE = PI_RCV_DATA_K_SIZE_MAX+128 to allow 128 byte
 * alignment for compatibility with old EISA boards.
 */
#define NEW_SKB_SIZE (PI_RCV_DATA_K_SIZE_MAX+128)

/* Define global routines */

int     dfx_probe(struct net_device *dev);

/* Define module-wide (static) routines */

static struct net_device *dfx_alloc_device(struct net_device *dev, u16 iobase);

static void             dfx_bus_init(struct net_device *dev);
static void             dfx_bus_config_check(DFX_board_t *bp);

static int              dfx_driver_init(struct net_device *dev);
static int              dfx_adap_init(DFX_board_t *bp);

static int              dfx_open(struct net_device *dev);
static int              dfx_close(struct net_device *dev);

static void             dfx_int_pr_halt_id(DFX_board_t *bp);
static void             dfx_int_type_0_process(DFX_board_t *bp);
static void             dfx_int_common(DFX_board_t *bp);
static void             dfx_interrupt(int irq, void *dev_id, struct pt_regs *regs);

static struct           net_device_stats *dfx_ctl_get_stats(struct net_device *dev);
static void             dfx_ctl_set_multicast_list(struct net_device *dev);
static int              dfx_ctl_set_mac_address(struct net_device *dev, void *addr);
static int              dfx_ctl_update_cam(DFX_board_t *bp);
static int              dfx_ctl_update_filters(DFX_board_t *bp);

static int              dfx_hw_dma_cmd_req(DFX_board_t *bp);
static int              dfx_hw_port_ctrl_req(DFX_board_t *bp, PI_UINT32 command, PI_UINT32 data_a, PI_UINT32 data_b, PI_UINT32 *host_data);
static void             dfx_hw_adap_reset(DFX_board_t *bp, PI_UINT32 type);
static int              dfx_hw_adap_state_rd(DFX_board_t *bp);
static int              dfx_hw_dma_uninit(DFX_board_t *bp, PI_UINT32 type);

static void             dfx_rcv_init(DFX_board_t *bp);
static void             dfx_rcv_queue_process(DFX_board_t *bp);

static int              dfx_xmt_queue_pkt(struct sk_buff *skb, struct net_device *dev);
static void             dfx_xmt_done(DFX_board_t *bp);
static void             dfx_xmt_flush(DFX_board_t *bp);

/* Define module-wide (static) variables */

static int              num_boards = 0;                 /* total number of adapters configured */
static int              already_probed = 0;             /* have we already entered dfx_probe? */

\f
/*
 * =======================
 * = dfx_port_write_byte =
 * = dfx_port_read_byte  =
 * = dfx_port_write_long =
 * = dfx_port_read_long  =
 * =======================
 *   
 * Overview:
 *   Routines for reading and writing values from/to adapter
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp     - pointer to board information
 *   offset - register offset from base I/O address
 *   data   - for dfx_port_write_byte and dfx_port_write_long, this
 *                        is a value to write.
 *                        for dfx_port_read_byte and dfx_port_read_byte, this
 *                        is a pointer to store the read value.
 *
 * Functional Description:
 *   These routines perform the correct operation to read or write
 *   the adapter register.
 *   
 *   EISA port block base addresses are based on the slot number in which the
 *   controller is installed.  For example, if the EISA controller is installed
 *   in slot 4, the port block base address is 0x4000.  If the controller is
 *   installed in slot 2, the port block base address is 0x2000, and so on.
 *   This port block can be used to access PDQ, ESIC, and DEFEA on-board
 *   registers using the register offsets defined in DEFXX.H.
 *
 *   PCI port block base addresses are assigned by the PCI BIOS or system
 *       firmware.  There is one 128 byte port block which can be accessed.  It
 *   allows for I/O mapping of both PDQ and PFI registers using the register
 *   offsets defined in DEFXX.H.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   bp->base_addr is a valid base I/O address for this adapter.
 *   offset is a valid register offset for this adapter.
 *
 * Side Effects:
 *   Rather than produce macros for these functions, these routines
 *   are defined using "inline" to ensure that the compiler will
 *   generate inline code and not waste a procedure call and return.
 *   This provides all the benefits of macros, but with the
 *   advantage of strict data type checking.
 */

static inline void dfx_port_write_byte(
        DFX_board_t     *bp,
        int                     offset,
        u8                      data
        )

        {
        u16 port = bp->base_addr + offset;

        outb(data, port);
        return;
        }

static inline void dfx_port_read_byte(
        DFX_board_t     *bp,
        int                     offset,
        u8                      *data
        )

        {
        u16 port = bp->base_addr + offset;

        *data = inb(port);
        return;
        }

static inline void dfx_port_write_long(
        DFX_board_t     *bp,
        int                     offset,
        u32                     data
        )

        {
        u16 port = bp->base_addr + offset;

        outl(data, port);
        return;
        }

static inline void dfx_port_read_long(
        DFX_board_t     *bp,
        int                     offset,
        u32                     *data
        )

        {
        u16 port = bp->base_addr + offset;

        *data = inl(port);
        return;
        }

\f
/*
 * =============
 * = dfx_probe =
 * =============
 *   
 * Overview:
 *   Probes for supported FDDI EISA and PCI controllers
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   dev - pointer to device information
 *
 * Functional Description:
 *   This routine is called by the OS for each FDDI device name (fddi0,
 *   fddi1,...,fddi6, fddi7) specified in drivers/net/Space.c.  Since
 *   the DEFXX.C driver currently does not support being loaded as a
 *   module, dfx_probe() will initialize all devices the first time
 *   it is called.
 *
 *   Let's say that dfx_probe() is getting called to initialize fddi0.
 *   Furthermore, let's say there are three supported controllers in the
 *   system.  Before dfx_probe() leaves, devices fddi0, fddi1, and fddi2
 *   will be initialized and a global flag will be set to indicate that
 *   dfx_probe() has already been called.
 *
 *   However...the OS doesn't know that we've already initialized
 *   devices fddi1 and fddi2 so dfx_probe() gets called again and again
 *   until it reaches the end of the device list for FDDI (presently,
 *   fddi7).  It's important that the driver "pretend" to probe for
 *   devices fddi1 and fddi2 and return success.  Devices fddi3
 *   through fddi7 will return failure since they weren't initialized.
 *
 *   This algorithm seems to work for the time being.  As other FDDI
 *   drivers are written for Linux, a more generic approach (perhaps
 *   similar to the Ethernet card approach) may need to be implemented.
 *   
 * Return Codes:
 *   0           - This device (fddi0, fddi1, etc) configured successfully
 *   -ENODEV - No devices present, or no Digital FDDI EISA or PCI device
 *                         present for this device name
 *
 * Assumptions:
 *   For the time being, DEFXX.C is the only FDDI driver under Linux.
 *   As this assumption changes, this routine will likely be impacted.
 *   Also, it is assumed that no more than eight (8) FDDI controllers
 *   will be configured in the system (fddi0 through fddi7).  This
 *   routine will not allocate new device structures.  If more than
 *   eight FDDI controllers need to be configured, drivers/net/Space.c
 *   should be updated as well as the DFX_MAX_NUM_BOARDS constant in
 *   DEFXX.H.
 *
 * Side Effects:
 *   Device structures for FDDI adapters (fddi0, fddi1, etc) are
 *   initialized and the board resources are read and stored in
 *   the device structure.
 */

int __init dfx_probe(struct net_device *dev)
{
        int                             i;                              /* used in for loops */
        int                             version_disp;   /* was version info string already displayed? */
        int                             port_len;               /* length of port address range (in bytes) */
        u16                             port;                   /* temporary I/O (port) address */
        struct pci_dev *                pdev = NULL;            /* PCI device record */
        u16                             command;                /* PCI Configuration space Command register val */
        u32                             slot_id;                /* EISA hardware (slot) ID read from adapter */
        DFX_board_t             *bp;                    /* board pointer */

        DBG_printk("In dfx_probe...\n");

        /*
         * Verify whether we're going through dfx_probe() again
         *
         * If so, see if we're going through for a subsequent fddi device that
         * we've already initialized.  If we are, return success (0).  If not,
         * return failure (-ENODEV).
         */

        version_disp = 0;                               /* default to version string not displayed */
        if (already_probed)
                {
                DBG_printk("Already entered dfx_probe\n");
                if (dev != NULL)
                        if ((strncmp(dev->name, "fddi", 4) == 0) && (dev->base_addr != 0))
                                {
                                DBG_printk("In dfx_probe for fddi adapter (%s) we've already initialized it, so return success\n", dev->name);
                                return(0);
                                }
                return(-ENODEV);
                }
        already_probed = 1;                     /* set global flag */

        /* Scan for FDDI EISA controllers */

        for (i=0; i < DFX_MAX_EISA_SLOTS; i++)          /* only scan for up to 16 EISA slots */
                {
                port = (i << 12) + PI_ESIC_K_SLOT_ID;   /* port = I/O address for reading slot ID */
                slot_id = inl(port);                                    /* read EISA HW (slot) ID */
                if ((slot_id & 0xF0FFFFFF) == DEFEA_PRODUCT_ID)
                        {
                        if (!version_disp)                                      /* display version info if adapter is found */
                                {
                                version_disp = 1;                               /* set display flag to TRUE so that */
                                printk(version);                                /* we only display this string ONCE */
                                }
                                
                        port = (i << 12);                                       /* recalc base addr */

                        /* Verify port address range is not already being used */

                        port_len = PI_ESIC_K_CSR_IO_LEN;
                        if (check_region(port, port_len) == 0)
                                {
                                /* Allocate a new device structure for this adapter */

                                dev = dfx_alloc_device(dev, port);
                                if (dev != NULL)
                                        {
                                        /* Initialize board structure with bus-specific info */

                                        bp = (DFX_board_t *) dev->priv;
                                        bp->dev = dev;
                                        bp->bus_type = DFX_BUS_TYPE_EISA;
                                        if (dfx_driver_init(dev) == DFX_K_SUCCESS)
                                                num_boards++;           /* only increment global board count on success */
                                        else
                                                dev->base_addr = 0;     /* clear port address field in device structure on failure */
                                        }
                                }
                        else
                                printk("I/O range allocated to adapter (0x%X-0x%X) is already being used!\n", port, (port + port_len-1));
                        }
                }

        /* Scan for FDDI PCI controllers */

        if (pci_present())                                              /* is PCI even present? */
                while ((pdev = pci_find_device(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_FDDI, pdev)))
                        {
                        if (!version_disp)                                      /* display version info if adapter is found */
                                {
                                version_disp = 1;                               /* set display flag to TRUE so that */
                                printk(version);                                /* we only display this string ONCE */
                                }

                        /* Verify that I/O enable bit is set (PCI slot is enabled) */

                        pci_read_config_word(pdev, PCI_COMMAND, &command);
                        if ((command & PCI_COMMAND_IO) == 0)
                                printk("I/O enable bit not set!  Verify that slot is enabled\n");
                        else
                                {
                                /* Turn off memory mapped space and enable mastering */

                                command |= PCI_COMMAND_MASTER;
                                command &= ~PCI_COMMAND_MEMORY;
                                pci_write_config_word(pdev, PCI_COMMAND, command);

                                /* Get I/O base address from PCI Configuration Space */

                                port = pdev->resource[1].start;

                                /* Verify port address range is not already being used */

                                port_len = PFI_K_CSR_IO_LEN;

                                if (check_region(port, port_len) == 0)
                                        {
                                        /* Allocate a new device structure for this adapter */

                                        dev = dfx_alloc_device(dev, port);
                                        if (dev != NULL)
                                                {
                                                /* Initialize board structure with bus-specific info */

                                                bp = (DFX_board_t *) dev->priv;
                                                bp->dev = dev;
                                                bp->bus_type = DFX_BUS_TYPE_PCI;
                                                bp->pci_dev = pdev;
                                                if (dfx_driver_init(dev) == DFX_K_SUCCESS)
                                                        num_boards++;           /* only increment global board count on success */
                                                else
                                                        dev->base_addr = 0;     /* clear port address field in device structure on failure */
                                                }
                                        }
                                else
                                        printk("I/O range allocated to adapter (0x%X-0x%X) is already being used!\n", port, (port + port_len-1));
                                }
                        }

        /*
         * If we're at this point we're going through dfx_probe() for the first
         * time.  Return success (0) if we've initialized 1 or more boards.
         * Otherwise, return failure (-ENODEV).
         */

        if (num_boards > 0)
                return(0);
        else
                return(-ENODEV);
        }

\f
/*
 * ====================
 * = dfx_alloc_device =
 * ====================
 *   
 * Overview:
 *   Allocate new device structure for adapter
 *  
 * Returns:
 *   Pointer to device structure for this adapter or NULL if
 *   none are available or could not allocate memory for
 *   private board structure.
 *       
 * Arguments:
 *   dev    - pointer to device information for last device
 *   iobase - base I/O address of new adapter
 *
 * Functional Description:
 *   The algorithm for allocating a new device structure is
 *   fairly simple.  Since we're presently the only FDDI driver
 *   under Linux, we'll find the first device structure with an
 *   "fddi*" device name that's free.  If we run out of devices,
 *   we'll fail on error.  This is simpler than trying to
 *   allocate the memory for a new device structure, determine
 *   the next free number (beyond 7) and link it into the chain
 *   of devices.  A user can always modify drivers/net/Space.c
 *   to add new FDDI device structures if necessary.
 *
 *   Beyond finding a free FDDI device structure, this routine
 *   initializes most of the fields, resource tags, and dispatch
 *   pointers in the device structure and calls the common
 *   fddi_setup() routine to perform the rest of the device
 *   structure initialization.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   If additional FDDI drivers are integrated into Linux,
 *   we'll likely need to use a different approach to
 *   allocate a device structure.  Perhaps one that is
 *   similar to what the Ethernet drivers use.
 *
 * Side Effects:
 *   None
 */

struct net_device __init *dfx_alloc_device( struct net_device *dev, u16 iobase)
{
        struct net_device *tmp_dev;             /* pointer to a device structure */

        DBG_printk("In dfx_alloc_device...\n");

        /* Find next free fddi entry */

        for (tmp_dev = dev; tmp_dev != NULL; tmp_dev = tmp_dev->next)
                if ((strncmp(tmp_dev->name, "fddi", 4) == 0) && (tmp_dev->base_addr == 0))
                        break;
        if (tmp_dev == NULL)
                {
                printk("Could not find free FDDI device structure for this adapter!\n");
                return(NULL);
                }
        DBG_printk("Device entry free, device name = %s\n", tmp_dev->name);

        /* Allocate space for private board structure */

        tmp_dev->priv = (void *) kmalloc(sizeof(DFX_board_t), GFP_KERNEL);
        if (tmp_dev->priv == NULL)
                {
                printk("Could not allocate memory for private board structure!\n");
                return(NULL);
                }
        memset(tmp_dev->priv, 0, sizeof(DFX_board_t));  /* clear structure */

        /* Initialize new device structure */

        tmp_dev->rmem_end       = 0;            /* shared memory isn't used */
        tmp_dev->rmem_start     = 0;            /* shared memory isn't used */
        tmp_dev->mem_end        = 0;            /* shared memory isn't used */
        tmp_dev->mem_start      = 0;            /* shared memory isn't used */
        tmp_dev->base_addr      = iobase;       /* save port (I/O) base address */
        tmp_dev->irq            = 0;            /* set in dfx_bus_init() */
        tmp_dev->if_port        = 0;            /* not applicable to FDDI adapters */
        tmp_dev->dma            = 0;            /* Bus Master DMA doesn't require channel */

        tmp_dev->get_stats                              = &dfx_ctl_get_stats;
        tmp_dev->open                                   = &dfx_open;
        tmp_dev->stop                                   = &dfx_close;
        tmp_dev->hard_start_xmit                = &dfx_xmt_queue_pkt;
        tmp_dev->hard_header                    = NULL;         /* set in fddi_setup() */
        tmp_dev->rebuild_header                 = NULL;         /* set in fddi_setup() */
        tmp_dev->set_multicast_list             = &dfx_ctl_set_multicast_list;
        tmp_dev->set_mac_address                = &dfx_ctl_set_mac_address;
        tmp_dev->do_ioctl                       = NULL;         /* not supported for now &&& */
        tmp_dev->set_config                     = NULL;         /* not supported for now &&& */
        tmp_dev->hard_header_cache              = NULL;         /* not supported */
        tmp_dev->header_cache_update            = NULL;         /* not supported */
        tmp_dev->change_mtu                     = NULL;         /* set in fddi_setup() */

        /* Initialize remaining device structure information */

        fddi_setup(tmp_dev);
        return(tmp_dev);
        }

\f
/*
 * ================
 * = dfx_bus_init =
 * ================
 *   
 * Overview:
 *   Initializes EISA and PCI controller bus-specific logic.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   dev - pointer to device information
 *
 * Functional Description:
 *   Determine and save adapter IRQ in device table,
 *   then perform bus-specific logic initialization.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   dev->base_addr has already been set with the proper
 *       base I/O address for this device.
 *
 * Side Effects:
 *   Interrupts are enabled at the adapter bus-specific logic.
 *   Note:  Interrupts at the DMA engine (PDQ chip) are not
 *   enabled yet.
 */

void __init dfx_bus_init(struct net_device *dev)
{
        DFX_board_t *bp = (DFX_board_t *)dev->priv;
        u8                      val;    /* used for I/O read/writes */

        DBG_printk("In dfx_bus_init...\n");

        /*
         * Initialize base I/O address field in bp structure
         *
         * Note: bp->base_addr is the same as dev->base_addr.
         *               It's useful because often we'll need to read
         *               or write registers where we already have the
         *               bp pointer instead of the dev pointer.  Having
         *               the base address in the bp structure will
         *               save a pointer dereference.
         *
         *               IMPORTANT!! This field must be defined before
         *               any of the dfx_port_* inline functions are
         *               called.
         */

        bp->base_addr = dev->base_addr;

        /* Initialize adapter based on bus type */

        if (bp->bus_type == DFX_BUS_TYPE_EISA)
                {
                /* Get the interrupt level from the ESIC chip */

                dfx_port_read_byte(bp, PI_ESIC_K_IO_CONFIG_STAT_0, &val);
                switch ((val & PI_CONFIG_STAT_0_M_IRQ) >> PI_CONFIG_STAT_0_V_IRQ)
                        {
                        case PI_CONFIG_STAT_0_IRQ_K_9:
                                dev->irq = 9;
                                break;

                        case PI_CONFIG_STAT_0_IRQ_K_10:
                                dev->irq = 10;
                                break;

                        case PI_CONFIG_STAT_0_IRQ_K_11:
                                dev->irq = 11;
                                break;

                        case PI_CONFIG_STAT_0_IRQ_K_15:
                                dev->irq = 15;
                                break;
                        }

                /* Enable access to I/O on the board by writing 0x03 to Function Control Register */

                dfx_port_write_byte(bp, PI_ESIC_K_FUNCTION_CNTRL, PI_ESIC_K_FUNCTION_CNTRL_IO_ENB);

                /* Set the I/O decode range of the board */

                val = ((dev->base_addr >> 12) << PI_IO_CMP_V_SLOT);
                dfx_port_write_byte(bp, PI_ESIC_K_IO_CMP_0_1, val);
                dfx_port_write_byte(bp, PI_ESIC_K_IO_CMP_1_1, val);

                /* Enable access to rest of module (including PDQ and packet memory) */

                dfx_port_write_byte(bp, PI_ESIC_K_SLOT_CNTRL, PI_SLOT_CNTRL_M_ENB);

                /*
                 * Map PDQ registers into I/O space.  This is done by clearing a bit
                 * in Burst Holdoff register.
                 */

                dfx_port_read_byte(bp, PI_ESIC_K_BURST_HOLDOFF, &val);
                dfx_port_write_byte(bp, PI_ESIC_K_BURST_HOLDOFF, (val & ~PI_BURST_HOLDOFF_M_MEM_MAP));

                /* Enable interrupts at EISA bus interface chip (ESIC) */

                dfx_port_read_byte(bp, PI_ESIC_K_IO_CONFIG_STAT_0, &val);
                dfx_port_write_byte(bp, PI_ESIC_K_IO_CONFIG_STAT_0, (val | PI_CONFIG_STAT_0_M_INT_ENB));
                }
        else
                {
                struct pci_dev *pdev = bp->pci_dev;

                /* Get the interrupt level from the PCI Configuration Table */

                dev->irq = pdev->irq;

                /* Check Latency Timer and set if less than minimal */

                pci_read_config_byte(pdev, PCI_LATENCY_TIMER, &val);
                if (val < PFI_K_LAT_TIMER_MIN)  /* if less than min, override with default */
                        {
                        val = PFI_K_LAT_TIMER_DEF;
                        pci_write_config_byte(pdev, PCI_LATENCY_TIMER, val);
                        }

                /* Enable interrupts at PCI bus interface chip (PFI) */

                dfx_port_write_long(bp, PFI_K_REG_MODE_CTRL, (PFI_MODE_M_PDQ_INT_ENB | PFI_MODE_M_DMA_ENB));
                }
        return;
        }

\f
/*
 * ========================
 * = dfx_bus_config_check =
 * ========================
 *   
 * Overview:
 *   Checks the configuration (burst size, full-duplex, etc.)  If any parameters
 *   are illegal, then this routine will set new defaults.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   For Revision 1 FDDI EISA, Revision 2 or later FDDI EISA with rev E or later
 *   PDQ, and all FDDI PCI controllers, all values are legal.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   dfx_adap_init has NOT been called yet so burst size and other items have
 *   not been set.
 *
 * Side Effects:
 *   None
 */

void __init dfx_bus_config_check(DFX_board_t *bp)
{
        int     status;                         /* return code from adapter port control call */
        u32     slot_id;                        /* EISA-bus hardware id (DEC3001, DEC3002,...) */
        u32     host_data;                      /* LW data returned from port control call */

        DBG_printk("In dfx_bus_config_check...\n");

        /* Configuration check only valid for EISA adapter */

        if (bp->bus_type == DFX_BUS_TYPE_EISA)
                {
                dfx_port_read_long(bp, PI_ESIC_K_SLOT_ID, &slot_id);

                /*
                 * First check if revision 2 EISA controller.  Rev. 1 cards used
                 * PDQ revision B, so no workaround needed in this case.  Rev. 3
                 * cards used PDQ revision E, so no workaround needed in this
                 * case, either.  Only Rev. 2 cards used either Rev. D or E
                 * chips, so we must verify the chip revision on Rev. 2 cards.
                 */

                if (slot_id == DEFEA_PROD_ID_2)
                        {
                        /*
                         * Revision 2 FDDI EISA controller found, so let's check PDQ
                         * revision of adapter.
                         */

                        status = dfx_hw_port_ctrl_req(bp,
                                                                                        PI_PCTRL_M_SUB_CMD,
                                                                                        PI_SUB_CMD_K_PDQ_REV_GET,
                                                                                        0,
                                                                                        &host_data);
                        if ((status != DFX_K_SUCCESS) || (host_data == 2))
                                {
                                /*
                                 * Either we couldn't determine the PDQ revision, or
                                 * we determined that it is at revision D.  In either case,
                                 * we need to implement the workaround.
                                 */

                                /* Ensure that the burst size is set to 8 longwords or less */

                                switch (bp->burst_size)
                                        {
                                        case PI_PDATA_B_DMA_BURST_SIZE_32:
                                        case PI_PDATA_B_DMA_BURST_SIZE_16:
                                                bp->burst_size = PI_PDATA_B_DMA_BURST_SIZE_8;
                                                break;

                                        default:
                                                break;
                                        }

                                /* Ensure that full-duplex mode is not enabled */

                                bp->full_duplex_enb = PI_SNMP_K_FALSE;
                                }
                        }
                }
        return;
        }

\f
/*
 * ===================
 * = dfx_driver_init =
 * ===================
 *   
 * Overview:
 *   Initializes remaining adapter board structure information
 *   and makes sure adapter is in a safe state prior to dfx_open().
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   dev - pointer to device information
 *
 * Functional Description:
 *   This function allocates additional resources such as the host memory
 *   blocks needed by the adapter (eg. descriptor and consumer blocks).
 *       Remaining bus initialization steps are also completed.  The adapter
 *   is also reset so that it is in the DMA_UNAVAILABLE state.  The OS
 *   must call dfx_open() to open the adapter and bring it on-line.
 *
 * Return Codes:
 *   DFX_K_SUCCESS      - initialization succeeded
 *   DFX_K_FAILURE      - initialization failed - could not allocate memory
 *                                              or read adapter MAC address
 *
 * Assumptions:
 *   Memory allocated from kmalloc() call is physically contiguous, locked
 *   memory whose physical address equals its virtual address.
 *
 * Side Effects:
 *   Adapter is reset and should be in DMA_UNAVAILABLE state before
 *   returning from this routine.
 */

int __init dfx_driver_init(struct net_device *dev)
{
        DFX_board_t *bp = (DFX_board_t *)dev->priv;
        int                     alloc_size;                     /* total buffer size needed */
        char            *top_v, *curr_v;        /* virtual addrs into memory block */
        u32                     top_p, curr_p;          /* physical addrs into memory block */
        u32                     data;                           /* host data register value */

        DBG_printk("In dfx_driver_init...\n");

        /* Initialize bus-specific hardware registers */

        dfx_bus_init(dev);

        /*
         * Initialize default values for configurable parameters
         *
         * Note: All of these parameters are ones that a user may
         *       want to customize.  It'd be nice to break these
         *               out into Space.c or someplace else that's more
         *               accessible/understandable than this file.
         */

        bp->full_duplex_enb             = PI_SNMP_K_FALSE;
        bp->req_ttrt                    = 8 * 12500;            /* 8ms in 80 nanosec units */
        bp->burst_size                  = PI_PDATA_B_DMA_BURST_SIZE_DEF;
        bp->rcv_bufs_to_post    = RCV_BUFS_DEF;

        /*
         * Ensure that HW configuration is OK
         *
         * Note: Depending on the hardware revision, we may need to modify
         *       some of the configurable parameters to workaround hardware
         *       limitations.  We'll perform this configuration check AFTER
         *       setting the parameters to their default values.
         */

        dfx_bus_config_check(bp);

        /* Disable PDQ interrupts first */

        dfx_port_write_long(bp, PI_PDQ_K_REG_HOST_INT_ENB, PI_HOST_INT_K_DISABLE_ALL_INTS);

        /* Place adapter in DMA_UNAVAILABLE state by resetting adapter */

        (void) dfx_hw_dma_uninit(bp, PI_PDATA_A_RESET_M_SKIP_ST);

        /*  Read the factory MAC address from the adapter then save it */

        if (dfx_hw_port_ctrl_req(bp,
                                                        PI_PCTRL_M_MLA,
                                                        PI_PDATA_A_MLA_K_LO,
                                                        0,
                                                        &data) != DFX_K_SUCCESS)
                {
                printk("%s: Could not read adapter factory MAC address!\n", dev->name);
                return(DFX_K_FAILURE);
                }
        memcpy(&bp->factory_mac_addr[0], &data, sizeof(u32));

        if (dfx_hw_port_ctrl_req(bp,
                                                        PI_PCTRL_M_MLA,
                                                        PI_PDATA_A_MLA_K_HI,
                                                        0,
                                                        &data) != DFX_K_SUCCESS)
                {
                printk("%s: Could not read adapter factory MAC address!\n", dev->name);
                return(DFX_K_FAILURE);
                }
        memcpy(&bp->factory_mac_addr[4], &data, sizeof(u16));

        /*
         * Set current address to factory address
         *
         * Note: Node address override support is handled through
         *       dfx_ctl_set_mac_address.
         */

        memcpy(dev->dev_addr, bp->factory_mac_addr, FDDI_K_ALEN);
        if (bp->bus_type == DFX_BUS_TYPE_EISA)
                printk("%s: DEFEA at I/O addr = 0x%lX, IRQ = %d, Hardware addr = %02X-%02X-%02X-%02X-%02X-%02X\n",
                                dev->name,
                                dev->base_addr,
                                dev->irq,
                                dev->dev_addr[0],
                                dev->dev_addr[1],
                                dev->dev_addr[2],
                                dev->dev_addr[3],
                                dev->dev_addr[4],
                                dev->dev_addr[5]);
        else
                printk("%s: DEFPA at I/O addr = 0x%lX, IRQ = %d, Hardware addr = %02X-%02X-%02X-%02X-%02X-%02X\n",
                                dev->name,
                                dev->base_addr,
                                dev->irq,
                                dev->dev_addr[0],
                                dev->dev_addr[1],
                                dev->dev_addr[2],
                                dev->dev_addr[3],
                                dev->dev_addr[4],
                                dev->dev_addr[5]);

        /*
         * Get memory for descriptor block, consumer block, and other buffers
         * that need to be DMA read or written to by the adapter.
         */

        alloc_size = sizeof(PI_DESCR_BLOCK) +
                                        PI_CMD_REQ_K_SIZE_MAX +
                                        PI_CMD_RSP_K_SIZE_MAX +
#ifndef DYNAMIC_BUFFERS
                                        (bp->rcv_bufs_to_post * PI_RCV_DATA_K_SIZE_MAX) +
#endif
                                        sizeof(PI_CONSUMER_BLOCK) +
                                        (PI_ALIGN_K_DESC_BLK - 1);
        top_v = (char *) kmalloc(alloc_size, GFP_KERNEL);
        if (top_v == NULL)
                {
                printk("%s: Could not allocate memory for host buffers and structures!\n", dev->name);
                return(DFX_K_FAILURE);
                }
        memset(top_v, 0, alloc_size);   /* zero out memory before continuing */
        top_p = virt_to_bus(top_v);             /* get physical address of buffer */

        /*
         *  To guarantee the 8K alignment required for the descriptor block, 8K - 1
         *  plus the amount of memory needed was allocated.  The physical address
         *      is now 8K aligned.  By carving up the memory in a specific order,
         *  we'll guarantee the alignment requirements for all other structures.
         *
         *  Note: If the assumptions change regarding the non-paged, non-cached,
         *                physically contiguous nature of the memory block or the address
         *                alignments, then we'll need to implement a different algorithm
         *                for allocating the needed memory.
         */

        curr_p = (u32) (ALIGN(top_p, PI_ALIGN_K_DESC_BLK));
        curr_v = top_v + (curr_p - top_p);

        /* Reserve space for descriptor block */

        bp->descr_block_virt = (PI_DESCR_BLOCK *) curr_v;
        bp->descr_block_phys = curr_p;
        curr_v += sizeof(PI_DESCR_BLOCK);
        curr_p += sizeof(PI_DESCR_BLOCK);

        /* Reserve space for command request buffer */

        bp->cmd_req_virt = (PI_DMA_CMD_REQ *) curr_v;
        bp->cmd_req_phys = curr_p;
        curr_v += PI_CMD_REQ_K_SIZE_MAX;
        curr_p += PI_CMD_REQ_K_SIZE_MAX;

        /* Reserve space for command response buffer */

        bp->cmd_rsp_virt = (PI_DMA_CMD_RSP *) curr_v;
        bp->cmd_rsp_phys = curr_p;
        curr_v += PI_CMD_RSP_K_SIZE_MAX;
        curr_p += PI_CMD_RSP_K_SIZE_MAX;

        /* Reserve space for the LLC host receive queue buffers */

        bp->rcv_block_virt = curr_v;
        bp->rcv_block_phys = curr_p;

#ifndef DYNAMIC_BUFFERS
        curr_v += (bp->rcv_bufs_to_post * PI_RCV_DATA_K_SIZE_MAX);
        curr_p += (bp->rcv_bufs_to_post * PI_RCV_DATA_K_SIZE_MAX);
#endif

        /* Reserve space for the consumer block */

        bp->cons_block_virt = (PI_CONSUMER_BLOCK *) curr_v;
        bp->cons_block_phys = curr_p;

        /* Display virtual and physical addresses if debug driver */

        DBG_printk("%s: Descriptor block virt = %0lX, phys = %0X\n",                            dev->name, (long)bp->descr_block_virt,  bp->descr_block_phys);
        DBG_printk("%s: Command Request buffer virt = %0lX, phys = %0X\n",                      dev->name, (long)bp->cmd_req_virt,              bp->cmd_req_phys);
        DBG_printk("%s: Command Response buffer virt = %0lX, phys = %0X\n",                     dev->name, (long)bp->cmd_rsp_virt,              bp->cmd_rsp_phys);
        DBG_printk("%s: Receive buffer block virt = %0lX, phys = %0X\n",                        dev->name, (long)bp->rcv_block_virt,    bp->rcv_block_phys);
        DBG_printk("%s: Consumer block virt = %0lX, phys = %0X\n",                                      dev->name, (long)bp->cons_block_virt,   bp->cons_block_phys);

        return(DFX_K_SUCCESS);
        }

\f
/*
 * =================
 * = dfx_adap_init =
 * =================
 *   
 * Overview:
 *   Brings the adapter to the link avail/link unavailable state.
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   Issues the low-level firmware/hardware calls necessary to bring
 *   the adapter up, or to properly reset and restore adapter during
 *   run-time.
 *
 * Return Codes:
 *   DFX_K_SUCCESS - Adapter brought up successfully
 *   DFX_K_FAILURE - Adapter initialization failed
 *
 * Assumptions:
 *   bp->reset_type should be set to a valid reset type value before
 *   calling this routine.
 *
 * Side Effects:
 *   Adapter should be in LINK_AVAILABLE or LINK_UNAVAILABLE state
 *   upon a successful return of this routine.
 */

int dfx_adap_init(
        DFX_board_t *bp
        )

        {
        DBG_printk("In dfx_adap_init...\n");

        /* Disable PDQ interrupts first */

        dfx_port_write_long(bp, PI_PDQ_K_REG_HOST_INT_ENB, PI_HOST_INT_K_DISABLE_ALL_INTS);

        /* Place adapter in DMA_UNAVAILABLE state by resetting adapter */

        if (dfx_hw_dma_uninit(bp, bp->reset_type) != DFX_K_SUCCESS)
                {
                printk("%s: Could not uninitialize/reset adapter!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /*
         * When the PDQ is reset, some false Type 0 interrupts may be pending,
         * so we'll acknowledge all Type 0 interrupts now before continuing.
         */

        dfx_port_write_long(bp, PI_PDQ_K_REG_TYPE_0_STATUS, PI_HOST_INT_K_ACK_ALL_TYPE_0);

        /*
         * Clear Type 1 and Type 2 registers before going to DMA_AVAILABLE state
         *
         * Note: We only need to clear host copies of these registers.  The PDQ reset
         *       takes care of the on-board register values.
         */

        bp->cmd_req_reg.lword   = 0;
        bp->cmd_rsp_reg.lword   = 0;
        bp->rcv_xmt_reg.lword   = 0;

        /* Clear consumer block before going to DMA_AVAILABLE state */

        memset(bp->cons_block_virt, 0, sizeof(PI_CONSUMER_BLOCK));

        /* Initialize the DMA Burst Size */

        if (dfx_hw_port_ctrl_req(bp,
                                                        PI_PCTRL_M_SUB_CMD,
                                                        PI_SUB_CMD_K_BURST_SIZE_SET,
                                                        bp->burst_size,
                                                        NULL) != DFX_K_SUCCESS)
                {
                printk("%s: Could not set adapter burst size!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /*
         * Set base address of Consumer Block
         *
         * Assumption: 32-bit physical address of consumer block is 64 byte
         *                         aligned.  That is, bits 0-5 of the address must be zero.
         */

        if (dfx_hw_port_ctrl_req(bp,
                                                        PI_PCTRL_M_CONS_BLOCK,
                                                        bp->cons_block_phys,
                                                        0,
                                                        NULL) != DFX_K_SUCCESS)
                {
                printk("%s: Could not set consumer block address!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /*
         * Set base address of Descriptor Block and bring adapter to DMA_AVAILABLE state
         *
         * Note: We also set the literal and data swapping requirements in this
         *           command.  Since this driver presently runs on Intel platforms
         *               which are Little Endian, we'll tell the adapter to byte swap
         *               data only.  This code will need to change when we support
         *               Big Endian systems (eg. PowerPC).
         *
         * Assumption: 32-bit physical address of descriptor block is 8Kbyte
         *             aligned.  That is, bits 0-12 of the address must be zero.
         */

        if (dfx_hw_port_ctrl_req(bp,
                                                        PI_PCTRL_M_INIT,
                                                        (u32) (bp->descr_block_phys | PI_PDATA_A_INIT_M_BSWAP_DATA),
                                                        0,
                                                        NULL) != DFX_K_SUCCESS)
                {
                printk("%s: Could not set descriptor block address!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /* Set transmit flush timeout value */

        bp->cmd_req_virt->cmd_type = PI_CMD_K_CHARS_SET;
        bp->cmd_req_virt->char_set.item[0].item_code    = PI_ITEM_K_FLUSH_TIME;
        bp->cmd_req_virt->char_set.item[0].value                = 3;    /* 3 seconds */
        bp->cmd_req_virt->char_set.item[0].item_index   = 0;
        bp->cmd_req_virt->char_set.item[1].item_code    = PI_ITEM_K_EOL;
        if (dfx_hw_dma_cmd_req(bp) != DFX_K_SUCCESS)
                {
                printk("%s: DMA command request failed!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /* Set the initial values for eFDXEnable and MACTReq MIB objects */

        bp->cmd_req_virt->cmd_type = PI_CMD_K_SNMP_SET;
        bp->cmd_req_virt->snmp_set.item[0].item_code    = PI_ITEM_K_FDX_ENB_DIS;
        bp->cmd_req_virt->snmp_set.item[0].value                = bp->full_duplex_enb;
        bp->cmd_req_virt->snmp_set.item[0].item_index   = 0;
        bp->cmd_req_virt->snmp_set.item[1].item_code    = PI_ITEM_K_MAC_T_REQ;
        bp->cmd_req_virt->snmp_set.item[1].value                = bp->req_ttrt;
        bp->cmd_req_virt->snmp_set.item[1].item_index   = 0;
        bp->cmd_req_virt->snmp_set.item[2].item_code    = PI_ITEM_K_EOL;
        if (dfx_hw_dma_cmd_req(bp) != DFX_K_SUCCESS)
                {
                printk("%s: DMA command request failed!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /* Initialize adapter CAM */

        if (dfx_ctl_update_cam(bp) != DFX_K_SUCCESS)
                {
                printk("%s: Adapter CAM update failed!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /* Initialize adapter filters */

        if (dfx_ctl_update_filters(bp) != DFX_K_SUCCESS)
                {
                printk("%s: Adapter filters update failed!\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /* Initialize receive descriptor block and produce buffers */

        dfx_rcv_init(bp);

        /* Issue START command and bring adapter to LINK_(UN)AVAILABLE state */

        bp->cmd_req_virt->cmd_type = PI_CMD_K_START;
        if (dfx_hw_dma_cmd_req(bp) != DFX_K_SUCCESS)
                {
                printk("%s: Start command failed\n", bp->dev->name);
                return(DFX_K_FAILURE);
                }

        /* Initialization succeeded, reenable PDQ interrupts */

        dfx_port_write_long(bp, PI_PDQ_K_REG_HOST_INT_ENB, PI_HOST_INT_K_ENABLE_DEF_INTS);
        return(DFX_K_SUCCESS);
        }

\f
/*
 * ============
 * = dfx_open =
 * ============
 *   
 * Overview:
 *   Opens the adapter
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   dev - pointer to device information
 *
 * Functional Description:
 *   This function brings the adapter to an operational state.
 *
 * Return Codes:
 *   0           - Adapter was successfully opened
 *   -EAGAIN - Could not register IRQ or adapter initialization failed
 *
 * Assumptions:
 *   This routine should only be called for a device that was
 *   initialized successfully during the dfx_probe process.
 *
 * Side Effects:
 *   Adapter should be in LINK_AVAILABLE or LINK_UNAVAILABLE state
 *   if the open is successful.
 */

int dfx_open(
        struct net_device *dev
        )

        {
        DFX_board_t     *bp = (DFX_board_t *)dev->priv;

        DBG_printk("In dfx_open...\n");

        /* Register IRQ - support shared interrupts by passing device ptr */

        if (request_irq(dev->irq, (void *)dfx_interrupt, SA_SHIRQ, dev->name, dev))
                {
                printk("%s: Requested IRQ %d is busy\n", dev->name, dev->irq);
                return(-EAGAIN);
                }

        /*
         * Set current address to factory MAC address
         *
         * Note: We've already done this step in dfx_driver_init.
         *       However, it's possible that a user has set a node
         *               address override, then closed and reopened the
         *               adapter.  Unless we reset the device address field
         *               now, we'll continue to use the existing modified
         *               address.
         */

        memcpy(dev->dev_addr, bp->factory_mac_addr, FDDI_K_ALEN);

        /* Clear local unicast/multicast address tables and counts */

        memset(bp->uc_table, 0, sizeof(bp->uc_table));
        memset(bp->mc_table, 0, sizeof(bp->mc_table));
        bp->uc_count = 0;
        bp->mc_count = 0;

        /* Disable promiscuous filter settings */

        bp->ind_group_prom      = PI_FSTATE_K_BLOCK;
        bp->group_prom          = PI_FSTATE_K_BLOCK;

        /* Reset and initialize adapter */

        bp->reset_type = PI_PDATA_A_RESET_M_SKIP_ST;    /* skip self-test */
        if (dfx_adap_init(bp) != DFX_K_SUCCESS)
                {
                printk("%s: Adapter open failed!\n", dev->name);
                return(-EAGAIN);
                }

        /* Set device structure info */

        dev->tbusy                      = 0;
        dev->interrupt          = DFX_UNMASK_INTERRUPTS;
        dev->start                      = 1;
        return(0);
        }

\f
/*
 * =============
 * = dfx_close =
 * =============
 *   
 * Overview:
 *   Closes the device/module.
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   dev - pointer to device information
 *
 * Functional Description:
 *   This routine closes the adapter and brings it to a safe state.
 *   The interrupt service routine is deregistered with the OS.
 *   The adapter can be opened again with another call to dfx_open().
 *
 * Return Codes:
 *   Always return 0.
 *
 * Assumptions:
 *   No further requests for this adapter are made after this routine is
 *   called.  dfx_open() can be called to reset and reinitialize the
 *   adapter.
 *
 * Side Effects:
 *   Adapter should be in DMA_UNAVAILABLE state upon completion of this
 *   routine.
 */

int dfx_close(
        struct net_device *dev
        )

        {
        DFX_board_t     *bp = (DFX_board_t *)dev->priv;

        DBG_printk("In dfx_close...\n");

        /* Disable PDQ interrupts first */

        dfx_port_write_long(bp, PI_PDQ_K_REG_HOST_INT_ENB, PI_HOST_INT_K_DISABLE_ALL_INTS);

        /* Place adapter in DMA_UNAVAILABLE state by resetting adapter */

        (void) dfx_hw_dma_uninit(bp, PI_PDATA_A_RESET_M_SKIP_ST);

        /*
         * Flush any pending transmit buffers
         *
         * Note: It's important that we flush the transmit buffers
         *               BEFORE we clear our copy of the Type 2 register.
         *               Otherwise, we'll have no idea how many buffers
         *               we need to free.
         */

        dfx_xmt_flush(bp);

        /*
         * Clear Type 1 and Type 2 registers after adapter reset
         *
         * Note: Even though we're closing the adapter, it's
         *       possible that an interrupt will occur after
         *               dfx_close is called.  Without some assurance to
         *               the contrary we want to make sure that we don't
         *               process receive and transmit LLC frames and update
         *               the Type 2 register with bad information.
         */

        bp->cmd_req_reg.lword   = 0;
        bp->cmd_rsp_reg.lword   = 0;
        bp->rcv_xmt_reg.lword   = 0;

        /* Clear consumer block for the same reason given above */

        memset(bp->cons_block_virt, 0, sizeof(PI_CONSUMER_BLOCK));

        /* Clear device structure flags */

        dev->start = 0;
        dev->tbusy = 1;

        /* Deregister (free) IRQ */

        free_irq(dev->irq, dev);
        return(0);
        }

\f
/*
 * ======================
 * = dfx_int_pr_halt_id =
 * ======================
 *   
 * Overview:
 *   Displays halt id's in string form.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   Determine current halt id and display appropriate string.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   None
 *
 * Side Effects:
 *   None
 */

void dfx_int_pr_halt_id(
        DFX_board_t     *bp
        )

        {
        PI_UINT32       port_status;                    /* PDQ port status register value */
        PI_UINT32       halt_id;                                /* PDQ port status halt ID */

        /* Read the latest port status */

        dfx_port_read_long(bp, PI_PDQ_K_REG_PORT_STATUS, &port_status);

        /* Display halt state transition information */

        halt_id = (port_status & PI_PSTATUS_M_HALT_ID) >> PI_PSTATUS_V_HALT_ID;
        switch (halt_id)
                {
                case PI_HALT_ID_K_SELFTEST_TIMEOUT:
                        printk("%s: Halt ID: Selftest Timeout\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_PARITY_ERROR:
                        printk("%s: Halt ID: Host Bus Parity Error\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_HOST_DIR_HALT:
                        printk("%s: Halt ID: Host-Directed Halt\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_SW_FAULT:
                        printk("%s: Halt ID: Adapter Software Fault\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_HW_FAULT:
                        printk("%s: Halt ID: Adapter Hardware Fault\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_PC_TRACE:
                        printk("%s: Halt ID: FDDI Network PC Trace Path Test\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_DMA_ERROR:
                        printk("%s: Halt ID: Adapter DMA Error\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_IMAGE_CRC_ERROR:
                        printk("%s: Halt ID: Firmware Image CRC Error\n", bp->dev->name);
                        break;

                case PI_HALT_ID_K_BUS_EXCEPTION:
                        printk("%s: Halt ID: 68000 Bus Exception\n", bp->dev->name);
                        break;

                default:
                        printk("%s: Halt ID: Unknown (code = %X)\n", bp->dev->name, halt_id);
                        break;
                }
        return;
        }

\f
/*
 * ==========================
 * = dfx_int_type_0_process =
 * ==========================
 *   
 * Overview:
 *   Processes Type 0 interrupts.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   Processes all enabled Type 0 interrupts.  If the reason for the interrupt
 *   is a serious fault on the adapter, then an error message is displayed
 *   and the adapter is reset.
 *
 *   One tricky potential timing window is the rapid succession of "link avail"
 *   "link unavail" state change interrupts.  The acknowledgement of the Type 0
 *   interrupt must be done before reading the state from the Port Status
 *   register.  This is true because a state change could occur after reading
 *   the data, but before acknowledging the interrupt.  If this state change
 *   does happen, it would be lost because the driver is using the old state,
 *   and it will never know about the new state because it subsequently
 *   acknowledges the state change interrupt.
 *
 *          INCORRECT                                      CORRECT
 *      read type 0 int reasons                   read type 0 int reasons
 *      read adapter state                        ack type 0 interrupts
 *      ack type 0 interrupts                     read adapter state
 *      ... process interrupt ...                 ... process interrupt ...
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   None
 *
 * Side Effects:
 *   An adapter reset may occur if the adapter has any Type 0 error interrupts
 *   or if the port status indicates that the adapter is halted.  The driver
 *   is responsible for reinitializing the adapter with the current CAM
 *   contents and adapter filter settings.
 */

void dfx_int_type_0_process(
        DFX_board_t     *bp
        )

        {
        PI_UINT32       type_0_status;          /* Host Interrupt Type 0 register */
        PI_UINT32       state;                          /* current adap state (from port status) */

        /*
         * Read host interrupt Type 0 register to determine which Type 0
         * interrupts are pending.  Immediately write it back out to clear
         * those interrupts.
         */

        dfx_port_read_long(bp, PI_PDQ_K_REG_TYPE_0_STATUS, &type_0_status);
        dfx_port_write_long(bp, PI_PDQ_K_REG_TYPE_0_STATUS, type_0_status);

        /* Check for Type 0 error interrupts */

        if (type_0_status & (PI_TYPE_0_STAT_M_NXM |
                                                        PI_TYPE_0_STAT_M_PM_PAR_ERR |
                                                        PI_TYPE_0_STAT_M_BUS_PAR_ERR))
                {
                /* Check for Non-Existent Memory error */

                if (type_0_status & PI_TYPE_0_STAT_M_NXM)
                        printk("%s: Non-Existent Memory Access Error\n", bp->dev->name);

                /* Check for Packet Memory Parity error */

                if (type_0_status & PI_TYPE_0_STAT_M_PM_PAR_ERR)
                        printk("%s: Packet Memory Parity Error\n", bp->dev->name);

                /* Check for Host Bus Parity error */

                if (type_0_status & PI_TYPE_0_STAT_M_BUS_PAR_ERR)
                        printk("%s: Host Bus Parity Error\n", bp->dev->name);

                /* Reset adapter and bring it back on-line */

                bp->link_available = PI_K_FALSE;        /* link is no longer available */
                bp->reset_type = 0;                                     /* rerun on-board diagnostics */
                printk("%s: Resetting adapter...\n", bp->dev->name);
                if (dfx_adap_init(bp) != DFX_K_SUCCESS)
                        {
                        printk("%s: Adapter reset failed!  Disabling adapter interrupts.\n", bp->dev->name);
                        dfx_port_write_long(bp, PI_PDQ_K_REG_HOST_INT_ENB, PI_HOST_INT_K_DISABLE_ALL_INTS);
                        return;
                        }
                printk("%s: Adapter reset successful!\n", bp->dev->name);
                return;
                }

        /* Check for transmit flush interrupt */

        if (type_0_status & PI_TYPE_0_STAT_M_XMT_FLUSH)
                {
                /* Flush any pending xmt's and acknowledge the flush interrupt */

                bp->link_available = PI_K_FALSE;                /* link is no longer available */
                dfx_xmt_flush(bp);                                              /* flush any outstanding packets */
                (void) dfx_hw_port_ctrl_req(bp,
                                                                        PI_PCTRL_M_XMT_DATA_FLUSH_DONE,
                                                                        0,
                                                                        0,
                                                                        NULL);
                }

        /* Check for adapter state change */

        if (type_0_status & PI_TYPE_0_STAT_M_STATE_CHANGE)
                {                     
                /* Get latest adapter state */

                state = dfx_hw_adap_state_rd(bp);       /* get adapter state */
                if (state == PI_STATE_K_HALTED)
                        {
                        /*
                         * Adapter has transitioned to HALTED state, try to reset
                         * adapter to bring it back on-line.  If reset fails,
                         * leave the adapter in the broken state.
                         */

                        printk("%s: Controller has transitioned to HALTED state!\n", bp->dev->name);
                        dfx_int_pr_halt_id(bp);                 /* display halt id as string */

                        /* Reset adapter and bring it back on-line */

                        bp->link_available = PI_K_FALSE;        /* link is no longer available */
                        bp->reset_type = 0;                                     /* rerun on-board diagnostics */
                        printk("%s: Resetting adapter...\n", bp->dev->name);
                        if (dfx_adap_init(bp) != DFX_K_SUCCESS)
                                {
                                printk("%s: Adapter reset failed!  Disabling adapter interrupts.\n", bp->dev->name);
                                dfx_port_write_long(bp, PI_PDQ_K_REG_HOST_INT_ENB, PI_HOST_INT_K_DISABLE_ALL_INTS);
                                return;
                                }
                        printk("%s: Adapter reset successful!\n", bp->dev->name);
                        }
                else if (state == PI_STATE_K_LINK_AVAIL)
                        {
                        bp->link_available = PI_K_TRUE;         /* set link available flag */
                        }
                }
        return;
        }

\f
/*
 * ==================
 * = dfx_int_common =
 * ==================
 *   
 * Overview:
 *   Interrupt service routine (ISR)
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   This is the ISR which processes incoming adapter interrupts.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   This routine assumes PDQ interrupts have not been disabled.
 *   When interrupts are disabled at the PDQ, the Port Status register
 *   is automatically cleared.  This routine uses the Port Status
 *   register value to determine whether a Type 0 interrupt occurred,
 *   so it's important that adapter interrupts are not normally
 *   enabled/disabled at the PDQ.
 *
 *   It's vital that this routine is NOT reentered for the
 *   same board and that the OS is not in another section of
 *   code (eg. dfx_xmt_queue_pkt) for the same board on a
 *   different thread.
 *
 * Side Effects:
 *   Pending interrupts are serviced.  Depending on the type of
 *   interrupt, acknowledging and clearing the interrupt at the
 *   PDQ involves writing a register to clear the interrupt bit
 *   or updating completion indices.
 */

void dfx_int_common(
        DFX_board_t     *bp
        )

        {
        PI_UINT32       port_status;            /* Port Status register */

        /* Process xmt interrupts - frequent case, so always call this routine */

        dfx_xmt_done(bp);                               /* free consumed xmt packets */

        /* Process rcv interrupts - frequent case, so always call this routine */

        dfx_rcv_queue_process(bp);              /* service received LLC frames */

        /*
         * Transmit and receive producer and completion indices are updated on the
         * adapter by writing to the Type 2 Producer register.  Since the frequent
         * case is that we'll be processing either LLC transmit or receive buffers,
         * we'll optimize I/O writes by doing a single register write here.
         */

        dfx_port_write_long(bp, PI_PDQ_K_REG_TYPE_2_PROD, bp->rcv_xmt_reg.lword);

        /* Read PDQ Port Status register to find out which interrupts need processing */

        dfx_port_read_long(bp, PI_PDQ_K_REG_PORT_STATUS, &port_status);

        /* Process Type 0 interrupts (if any) - infrequent, so only call when needed */

        if (port_status & PI_PSTATUS_M_TYPE_0_PENDING)
                dfx_int_type_0_process(bp);     /* process Type 0 interrupts */
        return;
        }

\f
/*
 * =================
 * = dfx_interrupt =
 * =================
 *   
 * Overview:
 *   Interrupt processing routine
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   irq        - interrupt vector
 *   dev_id     - pointer to device information
 *       regs   - pointer to registers structure
 *
 * Functional Description:
 *   This routine calls the interrupt processing routine for this adapter.  It
 *   disables and reenables adapter interrupts, as appropriate.  We can support
 *   shared interrupts since the incoming dev_id pointer provides our device
 *   structure context.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   The interrupt acknowledgement at the hardware level (eg. ACKing the PIC
 *   on Intel-based systems) is done by the operating system outside this
 *   routine.
 *
 *       System interrupts are enabled through this call.
 *
 * Side Effects:
 *   Interrupts are disabled, then reenabled at the adapter.
 */

void dfx_interrupt(
        int                             irq,
        void                    *dev_id,
        struct pt_regs  *regs
        )

        {
        struct net_device       *dev = (struct net_device *) dev_id;
        DFX_board_t             *bp;    /* private board structure pointer */
        u8                              tmp;    /* used for disabling/enabling ints */

        /* Get board pointer only if device structure is valid */

        if (dev == NULL)
                {
                printk("dfx_interrupt(): irq %d for unknown device!\n", irq);
                return;
                }
        bp = (DFX_board_t *) dev->priv;

        spin_lock(&bp->lock);
        
        /* See if we're already servicing an interrupt */

        if (dev->interrupt)
                printk("%s: Re-entering the interrupt handler!\n", dev->name);
        dev->interrupt = DFX_MASK_INTERRUPTS;   /* ensure non reentrancy */

        /* Service adapter interrupts */

        if (bp->bus_type == DFX_BUS_TYPE_PCI)
                {
                /* Disable PDQ-PFI interrupts at PFI */

                dfx_port_write_long(bp, PFI_K_REG_MODE_CTRL, PFI_MODE_M_DMA_ENB);

                /* Call interrupt service routine for this adapter */

                dfx_int_common(bp);

                /* Clear PDQ interrupt status bit and reenable interrupts */

                dfx_port_write_long(bp, PFI_K_REG_STATUS, PFI_STATUS_M_PDQ_INT);
                dfx_port_write_long(bp, PFI_K_REG_MODE_CTRL,
                                        (PFI_MODE_M_PDQ_INT_ENB + PFI_MODE_M_DMA_ENB));
                }
        else
                {
                /* Disable interrupts at the ESIC */

                dfx_port_read_byte(bp, PI_ESIC_K_IO_CONFIG_STAT_0, &tmp);
                tmp &= ~PI_CONFIG_STAT_0_M_INT_ENB;
                dfx_port_write_byte(bp, PI_ESIC_K_IO_CONFIG_STAT_0, tmp);

                /* Call interrupt service routine for this adapter */

                dfx_int_common(bp);

                /* Reenable interrupts at the ESIC */

                dfx_port_read_byte(bp, PI_ESIC_K_IO_CONFIG_STAT_0, &tmp);
                tmp |= PI_CONFIG_STAT_0_M_INT_ENB;
                dfx_port_write_byte(bp, PI_ESIC_K_IO_CONFIG_STAT_0, tmp);
                }

        dev->interrupt = DFX_UNMASK_INTERRUPTS;
        spin_unlock(&bp->lock);
        return;
        }

\f
/*
 * =====================
 * = dfx_ctl_get_stats =
 * =====================
 *   
 * Overview:
 *   Get statistics for FDDI adapter
 *  
 * Returns:
 *   Pointer to FDDI statistics structure
 *       
 * Arguments:
 *   dev - pointer to device information
 *
 * Functional Description:
 *   Gets current MIB objects from adapter, then
 *   returns FDDI statistics structure as defined
 *   in if_fddi.h.
 *
 *   Note: Since the FDDI statistics structure is
 *   still new and the device structure doesn't
 *   have an FDDI-specific get statistics handler,
 *   we'll return the FDDI statistics structure as
 *   a pointer to an Ethernet statistics structure.
 *   That way, at least the first part of the statistics
 *   structure can be decoded properly, and it allows
 *   "smart" applications to perform a second cast to
 *   decode the FDDI-specific statistics.
 *
 *   We'll have to pay attention to this routine as the
 *   device structure becomes more mature and LAN media
 *   independent.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   None
 *
 * Side Effects:
 *   None
 */

struct net_device_stats *dfx_ctl_get_stats(
        struct net_device *dev
        )

        {
        DFX_board_t     *bp = (DFX_board_t *)dev->priv;

        /* Fill the bp->stats structure with driver-maintained counters */

        bp->stats.rx_packets                    = bp->rcv_total_frames;
        bp->stats.tx_packets                    = bp->xmt_total_frames;
        bp->stats.rx_bytes                      = bp->rcv_total_bytes;
        bp->stats.tx_bytes                      = bp->xmt_total_bytes;
        bp->stats.rx_errors                             = (u32)(bp->rcv_crc_errors + bp->rcv_frame_status_errors + bp->rcv_length_errors);
        bp->stats.tx_errors                             = bp->xmt_length_errors;
        bp->stats.rx_dropped                    = bp->rcv_discards;
        bp->stats.tx_dropped                    = bp->xmt_discards;
        bp->stats.multicast                             = bp->rcv_multicast_frames;
        bp->stats.transmit_collision    = 0;    /* always zero (0) for FDDI */

        /* Get FDDI SMT MIB objects */

        bp->cmd_req_virt->cmd_type = PI_CMD_K_SMT_MIB_GET;
        if (dfx_hw_dma_cmd_req(bp) != DFX_K_SUCCESS)
                return((struct net_device_stats *) &bp->stats);

        /* Fill the bp->stats structure with the SMT MIB object values */

        memcpy(bp->stats.smt_station_id, &bp->cmd_rsp_virt->smt_mib_get.smt_station_id, sizeof(bp->cmd_rsp_virt->smt_mib_get.smt_station_id));
        bp->stats.smt_op_version_id                                     = bp->cmd_rsp_virt->smt_mib_get.smt_op_version_id;
        bp->stats.smt_hi_version_id                                     = bp->cmd_rsp_virt->smt_mib_get.smt_hi_version_id;
        bp->stats.smt_lo_version_id                                     = bp->cmd_rsp_virt->smt_mib_get.smt_lo_version_id;
        memcpy(bp->stats.smt_user_data, &bp->cmd_rsp_virt->smt_mib_get.smt_user_data, sizeof(bp->cmd_rsp_virt->smt_mib_get.smt_user_data));
        bp->stats.smt_mib_version_id                            = bp->cmd_rsp_virt->smt_mib_get.smt_mib_version_id;
        bp->stats.smt_mac_cts                                           = bp->cmd_rsp_virt->smt_mib_get.smt_mac_ct;
        bp->stats.smt_non_master_cts                            = bp->cmd_rsp_virt->smt_mib_get.smt_non_master_ct;
        bp->stats.smt_master_cts                                        = bp->cmd_rsp_virt->smt_mib_get.smt_master_ct;
        bp->stats.smt_available_paths                           = bp->cmd_rsp_virt->smt_mib_get.smt_available_paths;
        bp->stats.smt_config_capabilities                       = bp->cmd_rsp_virt->smt_mib_get.smt_config_capabilities;
        bp->stats.smt_config_policy                                     = bp->cmd_rsp_virt->smt_mib_get.smt_config_policy;
        bp->stats.smt_connection_policy                         = bp->cmd_rsp_virt->smt_mib_get.smt_connection_policy;
        bp->stats.smt_t_notify                                          = bp->cmd_rsp_virt->smt_mib_get.smt_t_notify;
        bp->stats.smt_stat_rpt_policy                           = bp->cmd_rsp_virt->smt_mib_get.smt_stat_rpt_policy;
        bp->stats.smt_trace_max_expiration                      = bp->cmd_rsp_virt->smt_mib_get.smt_trace_max_expiration;
        bp->stats.smt_bypass_present                            = bp->cmd_rsp_virt->smt_mib_get.smt_bypass_present;
        bp->stats.smt_ecm_state                                         = bp->cmd_rsp_virt->smt_mib_get.smt_ecm_state;
        bp->stats.smt_cf_state                                          = bp->cmd_rsp_virt->smt_mib_get.smt_cf_state;
        bp->stats.smt_remote_disconnect_flag            = bp->cmd_rsp_virt->smt_mib_get.smt_remote_disconnect_flag;
        bp->stats.smt_station_status                            = bp->cmd_rsp_virt->smt_mib_get.smt_station_status;
        bp->stats.smt_peer_wrap_flag                            = bp->cmd_rsp_virt->smt_mib_get.smt_peer_wrap_flag;
        bp->stats.smt_time_stamp                                        = bp->cmd_rsp_virt->smt_mib_get.smt_msg_time_stamp.ls;
        bp->stats.smt_transition_time_stamp                     = bp->cmd_rsp_virt->smt_mib_get.smt_transition_time_stamp.ls;
        bp->stats.mac_frame_status_functions            = bp->cmd_rsp_virt->smt_mib_get.mac_frame_status_functions;
        bp->stats.mac_t_max_capability                          = bp->cmd_rsp_virt->smt_mib_get.mac_t_max_capability;
        bp->stats.mac_tvx_capability                            = bp->cmd_rsp_virt->smt_mib_get.mac_tvx_capability;
        bp->stats.mac_available_paths                           = bp->cmd_rsp_virt->smt_mib_get.mac_available_paths;
        bp->stats.mac_current_path                                      = bp->cmd_rsp_virt->smt_mib_get.mac_current_path;
        memcpy(bp->stats.mac_upstream_nbr, &bp->cmd_rsp_virt->smt_mib_get.mac_upstream_nbr, FDDI_K_ALEN);
        memcpy(bp->stats.mac_downstream_nbr, &bp->cmd_rsp_virt->smt_mib_get.mac_downstream_nbr, FDDI_K_ALEN);
        memcpy(bp->stats.mac_old_upstream_nbr, &bp->cmd_rsp_virt->smt_mib_get.mac_old_upstream_nbr, FDDI_K_ALEN);
        memcpy(bp->stats.mac_old_downstream_nbr, &bp->cmd_rsp_virt->smt_mib_get.mac_old_downstream_nbr, FDDI_K_ALEN);
        bp->stats.mac_dup_address_test                          = bp->cmd_rsp_virt->smt_mib_get.mac_dup_address_test;
        bp->stats.mac_requested_paths                           = bp->cmd_rsp_virt->smt_mib_get.mac_requested_paths;
        bp->stats.mac_downstream_port_type                      = bp->cmd_rsp_virt->smt_mib_get.mac_downstream_port_type;
        memcpy(bp->stats.mac_smt_address, &bp->cmd_rsp_virt->smt_mib_get.mac_smt_address, FDDI_K_ALEN);
        bp->stats.mac_t_req                                                     = bp->cmd_rsp_virt->smt_mib_get.mac_t_req;
        bp->stats.mac_t_neg                                                     = bp->cmd_rsp_virt->smt_mib_get.mac_t_neg;
        bp->stats.mac_t_max                                                     = bp->cmd_rsp_virt->smt_mib_get.mac_t_max;
        bp->stats.mac_tvx_value                                         = bp->cmd_rsp_virt->smt_mib_get.mac_tvx_value;
        bp->stats.mac_frame_error_threshold                     = bp->cmd_rsp_virt->smt_mib_get.mac_frame_error_threshold;
        bp->stats.mac_frame_error_ratio                         = bp->cmd_rsp_virt->smt_mib_get.mac_frame_error_ratio;
        bp->stats.mac_rmt_state                                         = bp->cmd_rsp_virt->smt_mib_get.mac_rmt_state;
        bp->stats.mac_da_flag                                           = bp->cmd_rsp_virt->smt_mib_get.mac_da_flag;
        bp->stats.mac_una_da_flag                                       = bp->cmd_rsp_virt->smt_mib_get.mac_unda_flag;
        bp->stats.mac_frame_error_flag                          = bp->cmd_rsp_virt->smt_mib_get.mac_frame_error_flag;
        bp->stats.mac_ma_unitdata_available                     = bp->cmd_rsp_virt->smt_mib_get.mac_ma_unitdata_available;
        bp->stats.mac_hardware_present                          = bp->cmd_rsp_virt->smt_mib_get.mac_hardware_present;
        bp->stats.mac_ma_unitdata_enable                        = bp->cmd_rsp_virt->smt_mib_get.mac_ma_unitdata_enable;
        bp->stats.path_tvx_lower_bound                          = bp->cmd_rsp_virt->smt_mib_get.path_tvx_lower_bound;
        bp->stats.path_t_max_lower_bound                        = bp->cmd_rsp_virt->smt_mib_get.path_t_max_lower_bound;
        bp->stats.path_max_t_req                                        = bp->cmd_rsp_virt->smt_mib_get.path_max_t_req;
        memcpy(bp->stats.path_configuration, &bp->cmd_rsp_virt->smt_mib_get.path_configuration, sizeof(bp->cmd_rsp_virt->smt_mib_get.path_configuration));
        bp->stats.port_my_type[0]                                       = bp->cmd_rsp_virt->smt_mib_get.port_my_type[0];
        bp->stats.port_my_type[1]                                       = bp->cmd_rsp_virt->smt_mib_get.port_my_type[1];
        bp->stats.port_neighbor_type[0]                         = bp->cmd_rsp_virt->smt_mib_get.port_neighbor_type[0];
        bp->stats.port_neighbor_type[1]                         = bp->cmd_rsp_virt->smt_mib_get.port_neighbor_type[1];
        bp->stats.port_connection_policies[0]           = bp->cmd_rsp_virt->smt_mib_get.port_connection_policies[0];
        bp->stats.port_connection_policies[1]           = bp->cmd_rsp_virt->smt_mib_get.port_connection_policies[1];
        bp->stats.port_mac_indicated[0]                         = bp->cmd_rsp_virt->smt_mib_get.port_mac_indicated[0];
        bp->stats.port_mac_indicated[1]                         = bp->cmd_rsp_virt->smt_mib_get.port_mac_indicated[1];
        bp->stats.port_current_path[0]                          = bp->cmd_rsp_virt->smt_mib_get.port_current_path[0];
        bp->stats.port_current_path[1]                          = bp->cmd_rsp_virt->smt_mib_get.port_current_path[1];
        memcpy(&bp->stats.port_requested_paths[0*3], &bp->cmd_rsp_virt->smt_mib_get.port_requested_paths[0], 3);
        memcpy(&bp->stats.port_requested_paths[1*3], &bp->cmd_rsp_virt->smt_mib_get.port_requested_paths[1], 3);
        bp->stats.port_mac_placement[0]                         = bp->cmd_rsp_virt->smt_mib_get.port_mac_placement[0];
        bp->stats.port_mac_placement[1]                         = bp->cmd_rsp_virt->smt_mib_get.port_mac_placement[1];
        bp->stats.port_available_paths[0]                       = bp->cmd_rsp_virt->smt_mib_get.port_available_paths[0];
        bp->stats.port_available_paths[1]                       = bp->cmd_rsp_virt->smt_mib_get.port_available_paths[1];
        bp->stats.port_pmd_class[0]                                     = bp->cmd_rsp_virt->smt_mib_get.port_pmd_class[0];
        bp->stats.port_pmd_class[1]                                     = bp->cmd_rsp_virt->smt_mib_get.port_pmd_class[1];
        bp->stats.port_connection_capabilities[0]       = bp->cmd_rsp_virt->smt_mib_get.port_connection_capabilities[0];
        bp->stats.port_connection_capabilities[1]       = bp->cmd_rsp_virt->smt_mib_get.port_connection_capabilities[1];
        bp->stats.port_bs_flag[0]                                       = bp->cmd_rsp_virt->smt_mib_get.port_bs_flag[0];
        bp->stats.port_bs_flag[1]                                       = bp->cmd_rsp_virt->smt_mib_get.port_bs_flag[1];
        bp->stats.port_ler_estimate[0]                          = bp->cmd_rsp_virt->smt_mib_get.port_ler_estimate[0];
        bp->stats.port_ler_estimate[1]                          = bp->cmd_rsp_virt->smt_mib_get.port_ler_estimate[1];
        bp->stats.port_ler_cutoff[0]                            = bp->cmd_rsp_virt->smt_mib_get.port_ler_cutoff[0];
        bp->stats.port_ler_cutoff[1]                            = bp->cmd_rsp_virt->smt_mib_get.port_ler_cutoff[1];
        bp->stats.port_ler_alarm[0]                                     = bp->cmd_rsp_virt->smt_mib_get.port_ler_alarm[0];
        bp->stats.port_ler_alarm[1]                                     = bp->cmd_rsp_virt->smt_mib_get.port_ler_alarm[1];
        bp->stats.port_connect_state[0]                         = bp->cmd_rsp_virt->smt_mib_get.port_connect_state[0];
        bp->stats.port_connect_state[1]                         = bp->cmd_rsp_virt->smt_mib_get.port_connect_state[1];
        bp->stats.port_pcm_state[0]                                     = bp->cmd_rsp_virt->smt_mib_get.port_pcm_state[0];
        bp->stats.port_pcm_state[1]                                     = bp->cmd_rsp_virt->smt_mib_get.port_pcm_state[1];
        bp->stats.port_pc_withhold[0]                           = bp->cmd_rsp_virt->smt_mib_get.port_pc_withhold[0];
        bp->stats.port_pc_withhold[1]                           = bp->cmd_rsp_virt->smt_mib_get.port_pc_withhold[1];
        bp->stats.port_ler_flag[0]                                      = bp->cmd_rsp_virt->smt_mib_get.port_ler_flag[0];
        bp->stats.port_ler_flag[1]                                      = bp->cmd_rsp_virt->smt_mib_get.port_ler_flag[1];
        bp->stats.port_hardware_present[0]                      = bp->cmd_rsp_virt->smt_mib_get.port_hardware_present[0];
        bp->stats.port_hardware_present[1]                      = bp->cmd_rsp_virt->smt_mib_get.port_hardware_present[1];

        /* Get FDDI counters */

        bp->cmd_req_virt->cmd_type = PI_CMD_K_CNTRS_GET;
        if (dfx_hw_dma_cmd_req(bp) != DFX_K_SUCCESS)
                return((struct net_device_stats *) &bp->stats);

        /* Fill the bp->stats structure with the FDDI counter values */

        bp->stats.mac_frame_cts                         = bp->cmd_rsp_virt->cntrs_get.cntrs.frame_cnt.ls;
        bp->stats.mac_copied_cts                        = bp->cmd_rsp_virt->cntrs_get.cntrs.copied_cnt.ls;
        bp->stats.mac_transmit_cts                      = bp->cmd_rsp_virt->cntrs_get.cntrs.transmit_cnt.ls;
        bp->stats.mac_error_cts                         = bp->cmd_rsp_virt->cntrs_get.cntrs.error_cnt.ls;
        bp->stats.mac_lost_cts                          = bp->cmd_rsp_virt->cntrs_get.cntrs.lost_cnt.ls;
        bp->stats.port_lct_fail_cts[0]          = bp->cmd_rsp_virt->cntrs_get.cntrs.lct_rejects[0].ls;
        bp->stats.port_lct_fail_cts[1]          = bp->cmd_rsp_virt->cntrs_get.cntrs.lct_rejects[1].ls;
        bp->stats.port_lem_reject_cts[0]        = bp->cmd_rsp_virt->cntrs_get.cntrs.lem_rejects[0].ls;
        bp->stats.port_lem_reject_cts[1]        = bp->cmd_rsp_virt->cntrs_get.cntrs.lem_rejects[1].ls;
        bp->stats.port_lem_cts[0]                       = bp->cmd_rsp_virt->cntrs_get.cntrs.link_errors[0].ls;
        bp->stats.port_lem_cts[1]                       = bp->cmd_rsp_virt->cntrs_get.cntrs.link_errors[1].ls;

        return((struct net_device_stats *) &bp->stats);
        }

\f
/*
 * ==============================
 * = dfx_ctl_set_multicast_list =
 * ==============================
 *   
 * Overview:
 *   Enable/Disable LLC frame promiscuous mode reception
 *   on the adapter and/or update multicast address table.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   dev - pointer to device information
 *
 * Functional Description:
 *   This routine follows a fairly simple algorithm for setting the
 *   adapter filters and CAM:
 *
 *              if IFF_PROMISC flag is set
 *                      enable LLC individual/group promiscuous mode
 *              else
 *                      disable LLC individual/group promiscuous mode
 *                      if number of incoming multicast addresses >
 *                                      (CAM max size - number of unicast addresses in CAM)
 *                              enable LLC group promiscuous mode
 *                              set driver-maintained multicast address count to zero
 *                      else
 *                              disable LLC group promiscuous mode
 *                              set driver-maintained multicast address count to incoming count
 *                      update adapter CAM
 *              update adapter filters
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   Multicast addresses are presented in canonical (LSB) format.
 *
 * Side Effects:
 *   On-board adapter CAM and filters are updated.
 */

void dfx_ctl_set_multicast_list(
        struct net_device *dev
        )

        {
        DFX_board_t                     *bp = (DFX_board_t *)dev->priv;
        int                                     i;                      /* used as index in for loop */
        struct dev_mc_list      *dmi;           /* ptr to multicast addr entry */

        /* Enable LLC frame promiscuous mode, if necessary */

        if (dev->flags & IFF_PROMISC)
                bp->ind_group_prom = PI_FSTATE_K_PASS;          /* Enable LLC ind/group prom mode */

        /* Else, update multicast address table */

        else
                {
                bp->ind_group_prom = PI_FSTATE_K_BLOCK;         /* Disable LLC ind/group prom mode */
                /*
                 * Check whether incoming multicast address count exceeds table size
                 *
                 * Note: The adapters utilize an on-board 64 entry CAM for
                 *       supporting perfect filtering of multicast packets
                 *               and bridge functions when adding unicast addresses.
                 *               There is no hash function available.  To support
                 *               additional multicast addresses, the all multicast
                 *               filter (LLC group promiscuous mode) must be enabled.
                 *
                 *               The firmware reserves two CAM entries for SMT-related
                 *               multicast addresses, which leaves 62 entries available.
                 *               The following code ensures that we're not being asked
                 *               to add more than 62 addresses to the CAM.  If we are,
                 *               the driver will enable the all multicast filter.
                 *               Should the number of multicast addresses drop below
                 *               the high water mark, the filter will be disabled and
                 *               perfect filtering will be used.
                 */

                if (dev->mc_count > (PI_CMD_ADDR_FILTER_K_SIZE - bp->uc_count))
                        {
                        bp->group_prom  = PI_FSTATE_K_PASS;             /* Enable LLC group prom mode */
                        bp->mc_count    = 0;                                    /* Don't add mc addrs to CAM */
                        }
                else
                        {
                        bp->group_prom  = PI_FSTATE_K_BLOCK;    /* Disable LLC group prom mode */
                        bp->mc_count    = dev->mc_count;                /* Add mc addrs to CAM */
                        }

                /* Copy addresses to multicast address table, then update adapter CAM */

                dmi = dev->mc_list;                             /* point to first multicast addr */
                for (i=0; i < bp->mc_count; i++)
                        {
                        memcpy(&bp->mc_table[i*FDDI_K_ALEN], dmi->dmi_addr, FDDI_K_ALEN);
                        dmi = dmi->next;                        /* point to next multicast addr */
                        }
                if (dfx_ctl_update_cam(bp) != DFX_K_SUCCESS)
                        {
                        DBG_printk("%s: Could not update multicast address table!\n", dev->name);
                        }
                else
                        {
                        DBG_printk("%s: Multicast address table updated!  Added %d addresses.\n", dev->name, bp->mc_count);
                        }
                }

        /* Update adapter filters */

        if (dfx_ctl_update_filters(bp) != DFX_K_SUCCESS)
                {
                DBG_printk("%s: Could not update adapter filters!\n", dev->name);
                }
        else
                {
                DBG_printk("%s: Adapter filters updated!\n", dev->name);
                }
        return;
        }

\f
/*
 * ===========================
 * = dfx_ctl_set_mac_address =
 * ===========================
 *   
 * Overview:
 *   Add node address override (unicast address) to adapter
 *   CAM and update dev_addr field in device table.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   dev  - pointer to device information
 *   addr - pointer to sockaddr structure containing unicast address to add
 *
 * Functional Description:
 *   The adapter supports node address overrides by adding one or more
 *   unicast addresses to the adapter CAM.  This is similar to adding
 *   multicast addresses.  In this routine we'll update the driver and
 *   device structures with the new address, then update the adapter CAM
 *   to ensure that the adapter will copy and strip frames destined and
 *   sourced by that address.
 *
 * Return Codes:
 *   Always returns zero.
 *
 * Assumptions:
 *   The address pointed to by addr->sa_data is a valid unicast
 *   address and is presented in canonical (LSB) format.
 *
 * Side Effects:
 *   On-board adapter CAM is updated.  On-board adapter filters
 *   may be updated.
 */

int dfx_ctl_set_mac_address(
        struct net_device       *dev,
        void                    *addr
        )

        {
        DFX_board_t             *bp = (DFX_board_t *)dev->priv;
        struct sockaddr *p_sockaddr = (struct sockaddr *)addr;

        /* Copy unicast address to driver-maintained structs and update count */

        memcpy(dev->dev_addr, p_sockaddr->sa_data, FDDI_K_ALEN);        /* update device struct */
        memcpy(&bp->uc_table[0], p_sockaddr->sa_data, FDDI_K_ALEN);     /* update driver struct */
        bp->uc_count = 1;

        /*
         * Verify we're not exceeding the CAM size by adding unicast address
         *
         * Note: It's possible that before entering this routine we've
         *       already filled the CAM with 62 multicast addresses.
         *               Since we need to place the node address override into
         *               the CAM, we have to check to see that we're not
         *               exceeding the CAM size.  If we are, we have to enable
         *               the LLC group (multicast) promiscuous mode filter as
         *               in dfx_ctl_set_multicast_list.
         */

        if ((bp->uc_count + bp->mc_count) > PI_CMD_ADDR_FILTER_K_SIZE)
                {
                bp->group_prom  = PI_FSTATE_K_PASS;             /* Enable LLC group prom mode */
                bp->mc_count    = 0;                                    /* Don't add mc addrs to CAM */

                /* Update adapter filters */

                if (dfx_ctl_update_filters(bp) != DFX_K_SUCCESS)
                        {
                        DBG_printk("%s: Could not update adapter filters!\n", dev->name);
                        }
                else
                        {
                        DBG_printk("%s: Adapter filters updated!\n", dev->name);
                        }
                }

        /* Update adapter CAM with new unicast address */

        if (dfx_ctl_update_cam(bp) != DFX_K_SUCCESS)
                {
                DBG_printk("%s: Could not set new MAC address!\n", dev->name);
                }
        else
                {
                DBG_printk("%s: Adapter CAM updated with new MAC address\n", dev->name);
                }
        return(0);                      /* always return zero */
        }

\f
/*
 * ======================
 * = dfx_ctl_update_cam =
 * ======================
 *
 * Overview:
 *   Procedure to update adapter CAM (Content Addressable Memory)
 *   with desired unicast and multicast address entries.
 *
 * Returns:
 *   Condition code
 *
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   Updates adapter CAM with current contents of board structure
 *   unicast and multicast address tables.  Since there are only 62
 *   free entries in CAM, this routine ensures that the command
 *   request buffer is not overrun.
 *
 * Return Codes:
 *   DFX_K_SUCCESS - Request succeeded
 *   DFX_K_FAILURE - Request failed
 *
 * Assumptions:
 *   All addresses being added (unicast and multicast) are in canonical
 *   order.
 *
 * Side Effects:
 *   On-board adapter CAM is updated.
 */

int dfx_ctl_update_cam(
        DFX_board_t *bp
        )

        {
        int                     i;                              /* used as index */
        PI_LAN_ADDR     *p_addr;                /* pointer to CAM entry */

        /*
         * Fill in command request information
         *
         * Note: Even though both the unicast and multicast address
         *       table entries are stored as contiguous 6 byte entries,
         *               the firmware address filter set command expects each
         *               entry to be two longwords (8 bytes total).  We must be
         *               careful to only copy the six bytes of each unicast and
         *               multicast table entry into each command entry.  This
         *               is also why we must first clear the entire command
         *               request buffer.
         */

        memset(bp->cmd_req_virt, 0, PI_CMD_REQ_K_SIZE_MAX);     /* first clear buffer */
        bp->cmd_req_virt->cmd_type = PI_CMD_K_ADDR_FILTER_SET;
        p_addr = &bp->cmd_req_virt->addr_filter_set.entry[0];

        /* Now add unicast addresses to command request buffer, if any */

        for (i=0; i < (int)bp->uc_count; i++)
                {
                if (i < PI_CMD_ADDR_FILTER_K_SIZE)
                        {
                        memcpy(p_addr, &bp->uc_table[i*FDDI_K_ALEN], FDDI_K_ALEN);
                        p_addr++;                       /* point to next command entry */
                        }
                }

        /* Now add multicast addresses to command request buffer, if any */

        for (i=0; i < (int)bp->mc_count; i++)
                {
                if ((i + bp->uc_count) < PI_CMD_ADDR_FILTER_K_SIZE)
                        {
                        memcpy(p_addr, &bp->mc_table[i*FDDI_K_ALEN], FDDI_K_ALEN);
                        p_addr++;                       /* point to next command entry */
                        }
                }

        /* Issue command to update adapter CAM, then return */

        if (dfx_hw_dma_cmd_req(bp) != DFX_K_SUCCESS)
                return(DFX_K_FAILURE);
        return(DFX_K_SUCCESS);
        }

\f
/*
 * ==========================
 * = dfx_ctl_update_filters =
 * ==========================
 *
 * Overview:
 *   Procedure to update adapter filters with desired
 *   filter settings.
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   Enables or disables filter using current filter settings.
 *
 * Return Codes:
 *   DFX_K_SUCCESS - Request succeeded.
 *   DFX_K_FAILURE - Request failed.
 *
 * Assumptions:
 *   We must always pass up packets destined to the broadcast
 *   address (FF-FF-FF-FF-FF-FF), so we'll always keep the
 *   broadcast filter enabled.
 *
 * Side Effects:
 *   On-board adapter filters are updated.
 */

int dfx_ctl_update_filters(
        DFX_board_t *bp
        )

        {
        int     i = 0;                                  /* used as index */

        /* Fill in command request information */

        bp->cmd_req_virt->cmd_type = PI_CMD_K_FILTERS_SET;

        /* Initialize Broadcast filter - * ALWAYS ENABLED * */

        bp->cmd_req_virt->filter_set.item[i].item_code  = PI_ITEM_K_BROADCAST;
        bp->cmd_req_virt->filter_set.item[i++].value    = PI_FSTATE_K_PASS;

        /* Initialize LLC Individual/Group Promiscuous filter */

        bp->cmd_req_virt->filter_set.item[i].item_code  = PI_ITEM_K_IND_GROUP_PROM;
        bp->cmd_req_virt->filter_set.item[i++].value    = bp->ind_group_prom;

        /* Initialize LLC Group Promiscuous filter */

        bp->cmd_req_virt->filter_set.item[i].item_code  = PI_ITEM_K_GROUP_PROM;
        bp->cmd_req_virt->filter_set.item[i++].value    = bp->group_prom;

        /* Terminate the item code list */

        bp->cmd_req_virt->filter_set.item[i].item_code  = PI_ITEM_K_EOL;

        /* Issue command to update adapter filters, then return */

        if (dfx_hw_dma_cmd_req(bp) != DFX_K_SUCCESS)
                return(DFX_K_FAILURE);
        return(DFX_K_SUCCESS);
        }

\f
/*
 * ======================
 * = dfx_hw_dma_cmd_req =
 * ======================
 *   
 * Overview:
 *   Sends PDQ DMA command to adapter firmware
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   The command request and response buffers are posted to the adapter in the manner
 *   described in the PDQ Port Specification:
 *
 *              1. Command Response Buffer is posted to adapter.
 *              2. Command Request Buffer is posted to adapter.
 *              3. Command Request consumer index is polled until it indicates that request
 *         buffer has been DMA'd to adapter.
 *              4. Command Response consumer index is polled until it indicates that response
 *         buffer has been DMA'd from adapter.
 *
 *   This ordering ensures that a response buffer is already available for the firmware
 *   to use once it's done processing the request buffer.
 *
 * Return Codes:
 *   DFX_K_SUCCESS        - DMA command succeeded
 *       DFX_K_OUTSTATE   - Adapter is NOT in proper state
 *   DFX_K_HW_TIMEOUT - DMA command timed out
 *
 * Assumptions:
 *   Command request buffer has already been filled with desired DMA command.
 *
 * Side Effects:
 *   None
 */

int dfx_hw_dma_cmd_req(
        DFX_board_t *bp
        )

        {
        int status;                     /* adapter status */
        int timeout_cnt;        /* used in for loops */
        
        /* Make sure the adapter is in a state that we can issue the DMA command in */
        
        status = dfx_hw_adap_state_rd(bp);
        if ((status == PI_STATE_K_RESET)                ||
                (status == PI_STATE_K_HALTED)           ||
                (status == PI_STATE_K_DMA_UNAVAIL)      ||
                (status == PI_STATE_K_UPGRADE))
                return(DFX_K_OUTSTATE);

        /* Put response buffer on the command response queue */

        bp->descr_block_virt->cmd_rsp[bp->cmd_rsp_reg.index.prod].long_0 = (u32) (PI_RCV_DESCR_M_SOP |
                        ((PI_CMD_RSP_K_SIZE_MAX / PI_ALIGN_K_CMD_RSP_BUFF) << PI_RCV_DESCR_V_SEG_LEN));
        bp->descr_block_virt->cmd_rsp[bp->cmd_rsp_reg.index.prod].long_1 = bp->cmd_rsp_phys;

        /* Bump (and wrap) the producer index and write out to register */

        bp->cmd_rsp_reg.index.prod += 1;
        bp->cmd_rsp_reg.index.prod &= PI_CMD_RSP_K_NUM_ENTRIES-1;
        dfx_port_write_long(bp, PI_PDQ_K_REG_CMD_RSP_PROD, bp->cmd_rsp_reg.lword);

        /* Put request buffer on the command request queue */
        
        bp->descr_block_virt->cmd_req[bp->cmd_req_reg.index.prod].long_0 = (u32) (PI_XMT_DESCR_M_SOP |
                        PI_XMT_DESCR_M_EOP | (PI_CMD_REQ_K_SIZE_MAX << PI_XMT_DESCR_V_SEG_LEN));
        bp->descr_block_virt->cmd_req[bp->cmd_req_reg.index.prod].long_1 = bp->cmd_req_phys;

        /* Bump (and wrap) the producer index and write out to register */

        bp->cmd_req_reg.index.prod += 1;
        bp->cmd_req_reg.index.prod &= PI_CMD_REQ_K_NUM_ENTRIES-1;
        dfx_port_write_long(bp, PI_PDQ_K_REG_CMD_REQ_PROD, bp->cmd_req_reg.lword);

        /*
         * Here we wait for the command request consumer index to be equal
         * to the producer, indicating that the adapter has DMAed the request.
         */

        for (timeout_cnt = 20000; timeout_cnt > 0; timeout_cnt--)
                {
                if (bp->cmd_req_reg.index.prod == (u8)(bp->cons_block_virt->cmd_req))
                        break;
                udelay(100);                    /* wait for 100 microseconds */
                }
        if (timeout_cnt == 0) 
                return(DFX_K_HW_TIMEOUT);

        /* Bump (and wrap) the completion index and write out to register */

        bp->cmd_req_reg.index.comp += 1;
        bp->cmd_req_reg.index.comp &= PI_CMD_REQ_K_NUM_ENTRIES-1;
        dfx_port_write_long(bp, PI_PDQ_K_REG_CMD_REQ_PROD, bp->cmd_req_reg.lword);

        /*
         * Here we wait for the command response consumer index to be equal
         * to the producer, indicating that the adapter has DMAed the response.
         */

        for (timeout_cnt = 20000; timeout_cnt > 0; timeout_cnt--)
                {
                if (bp->cmd_rsp_reg.index.prod == (u8)(bp->cons_block_virt->cmd_rsp))
                        break;
                udelay(100);                    /* wait for 100 microseconds */
                }
        if (timeout_cnt == 0) 
                return(DFX_K_HW_TIMEOUT);

        /* Bump (and wrap) the completion index and write out to register */

        bp->cmd_rsp_reg.index.comp += 1;
        bp->cmd_rsp_reg.index.comp &= PI_CMD_RSP_K_NUM_ENTRIES-1;
        dfx_port_write_long(bp, PI_PDQ_K_REG_CMD_RSP_PROD, bp->cmd_rsp_reg.lword);
        return(DFX_K_SUCCESS);
        }

\f
/*
 * ========================
 * = dfx_hw_port_ctrl_req =
 * ========================
 *   
 * Overview:
 *   Sends PDQ port control command to adapter firmware
 *  
 * Returns:
 *   Host data register value in host_data if ptr is not NULL
 *       
 * Arguments:
 *   bp                 - pointer to board information
 *       command        - port control command
 *       data_a         - port data A register value
 *       data_b         - port data B register value
 *       host_data      - ptr to host data register value
 *
 * Functional Description:
 *   Send generic port control command to adapter by writing
 *   to various PDQ port registers, then polling for completion.
 *
 * Return Codes:
 *   DFX_K_SUCCESS        - port control command succeeded
 *   DFX_K_HW_TIMEOUT - port control command timed out
 *
 * Assumptions:
 *   None
 *
 * Side Effects:
 *   None
 */

int dfx_hw_port_ctrl_req(
        DFX_board_t     *bp,
        PI_UINT32       command,
        PI_UINT32       data_a,
        PI_UINT32       data_b,
        PI_UINT32       *host_data
        )

        {
        PI_UINT32       port_cmd;               /* Port Control command register value */
        int                     timeout_cnt;    /* used in for loops */

        /* Set Command Error bit in command longword */
        
        port_cmd = (PI_UINT32) (command | PI_PCTRL_M_CMD_ERROR);

        /* Issue port command to the adapter */

        dfx_port_write_long(bp, PI_PDQ_K_REG_PORT_DATA_A, data_a);
        dfx_port_write_long(bp, PI_PDQ_K_REG_PORT_DATA_B, data_b);
        dfx_port_write_long(bp, PI_PDQ_K_REG_PORT_CTRL, port_cmd);

        /* Now wait for command to complete */

        if (command == PI_PCTRL_M_BLAST_FLASH)
                timeout_cnt = 600000;   /* set command timeout count to 60 seconds */
        else
                timeout_cnt = 20000;    /* set command timeout count to 2 seconds */

        for (; timeout_cnt > 0; timeout_cnt--)
                {
                dfx_port_read_long(bp, PI_PDQ_K_REG_PORT_CTRL, &port_cmd);
                if (!(port_cmd & PI_PCTRL_M_CMD_ERROR))
                        break;
                udelay(100);                    /* wait for 100 microseconds */
                }
        if (timeout_cnt == 0) 
                return(DFX_K_HW_TIMEOUT);

        /*
         * If the address of host_data is non-zero, assume caller has supplied a  
         * non NULL pointer, and return the contents of the HOST_DATA register in 
         * it.
         */

        if (host_data != NULL)
                dfx_port_read_long(bp, PI_PDQ_K_REG_HOST_DATA, host_data);
        return(DFX_K_SUCCESS);
        }

\f
/*
 * =====================
 * = dfx_hw_adap_reset =
 * =====================
 *   
 * Overview:
 *   Resets adapter
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp   - pointer to board information
 *   type - type of reset to perform
 *
 * Functional Description:
 *   Issue soft reset to adapter by writing to PDQ Port Reset
 *   register.  Use incoming reset type to tell adapter what
 *   kind of reset operation to perform.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   This routine merely issues a soft reset to the adapter.
 *   It is expected that after this routine returns, the caller
 *   will appropriately poll the Port Status register for the
 *   adapter to enter the proper state.
 *
 * Side Effects:
 *   Internal adapter registers are cleared.
 */

void dfx_hw_adap_reset(
        DFX_board_t     *bp,
        PI_UINT32       type
        )

        {
        /* Set Reset type and assert reset */

        dfx_port_write_long(bp, PI_PDQ_K_REG_PORT_DATA_A, type);        /* tell adapter type of reset */
        dfx_port_write_long(bp, PI_PDQ_K_REG_PORT_RESET, PI_RESET_M_ASSERT_RESET);

        /* Wait for at least 1 Microsecond according to the spec. We wait 20 just to be safe */

        udelay(20);

        /* Deassert reset */

        dfx_port_write_long(bp, PI_PDQ_K_REG_PORT_RESET, 0);
        return;
        }

\f
/*
 * ========================
 * = dfx_hw_adap_state_rd =
 * ========================
 *   
 * Overview:
 *   Returns current adapter state
 *  
 * Returns:
 *   Adapter state per PDQ Port Specification
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   Reads PDQ Port Status register and returns adapter state.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   None
 *
 * Side Effects:
 *   None
 */

int dfx_hw_adap_state_rd(
        DFX_board_t *bp
        )

        {
        PI_UINT32 port_status;          /* Port Status register value */

        dfx_port_read_long(bp, PI_PDQ_K_REG_PORT_STATUS, &port_status);
        return((port_status & PI_PSTATUS_M_STATE) >> PI_PSTATUS_V_STATE);
        }

\f
/*
 * =====================
 * = dfx_hw_dma_uninit =
 * =====================
 *   
 * Overview:
 *   Brings adapter to DMA_UNAVAILABLE state
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   bp   - pointer to board information
 *   type - type of reset to perform
 *
 * Functional Description:
 *   Bring adapter to DMA_UNAVAILABLE state by performing the following:
 *              1. Set reset type bit in Port Data A Register then reset adapter.
 *              2. Check that adapter is in DMA_UNAVAILABLE state.
 *
 * Return Codes:
 *   DFX_K_SUCCESS        - adapter is in DMA_UNAVAILABLE state
 *   DFX_K_HW_TIMEOUT - adapter did not reset properly
 *
 * Assumptions:
 *   None
 *
 * Side Effects:
 *   Internal adapter registers are cleared.
 */

int dfx_hw_dma_uninit(
        DFX_board_t     *bp,
        PI_UINT32       type
        )

        {
        int timeout_cnt;        /* used in for loops */

        /* Set reset type bit and reset adapter */

        dfx_hw_adap_reset(bp, type);

        /* Now wait for adapter to enter DMA_UNAVAILABLE state */

        for (timeout_cnt = 100000; timeout_cnt > 0; timeout_cnt--)
                {
                if (dfx_hw_adap_state_rd(bp) == PI_STATE_K_DMA_UNAVAIL)
                        break;
                udelay(100);                                    /* wait for 100 microseconds */
                }
        if (timeout_cnt == 0) 
                return(DFX_K_HW_TIMEOUT);
        return(DFX_K_SUCCESS);
        }


/*
 *      Align an sk_buff to a boundary power of 2
 *
 */
 
void my_skb_align(struct sk_buff *skb, int n)
{
        u32 x=(u32)skb->data;   /* We only want the low bits .. */
        u32 v;
        
        v=(x+n-1)&~(n-1);       /* Where we want to be */
        
        skb_reserve(skb, v-x);
}

\f
/*
 * ================
 * = dfx_rcv_init =
 * ================
 *   
 * Overview:
 *   Produces buffers to adapter LLC Host receive descriptor block
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   This routine can be called during dfx_adap_init() or during an adapter
 *       reset.  It initializes the descriptor block and produces all allocated
 *   LLC Host queue receive buffers.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   The PDQ has been reset and the adapter and driver maintained Type 2
 *   register indices are cleared.
 *
 * Side Effects:
 *   Receive buffers are posted to the adapter LLC queue and the adapter
 *   is notified.
 */

void dfx_rcv_init(
        DFX_board_t *bp
        )

        {
        int     i, j;                                   /* used in for loop */

        /*
         *  Since each receive buffer is a single fragment of same length, initialize
         *  first longword in each receive descriptor for entire LLC Host descriptor
         *  block.  Also initialize second longword in each receive descriptor with
         *  physical address of receive buffer.  We'll always allocate receive
         *  buffers in powers of 2 so that we can easily fill the 256 entry descriptor
         *  block and produce new receive buffers by simply updating the receive
         *  producer index.
         *
         *      Assumptions:
         *              To support all shipping versions of PDQ, the receive buffer size
         *              must be mod 128 in length and the physical address must be 128 byte
         *              aligned.  In other words, bits 0-6 of the length and address must
         *              be zero for the following descriptor field entries to be correct on
         *              all PDQ-based boards.  We guaranteed both requirements during
         *              driver initialization when we allocated memory for the receive buffers.
         */

#ifdef DYNAMIC_BUFFERS
        for (i = 0; i < (int)(bp->rcv_bufs_to_post); i++)
                for (j = 0; (i + j) < (int)PI_RCV_DATA_K_NUM_ENTRIES; j += bp->rcv_bufs_to_post)
                {
                        struct sk_buff *newskb;
                        bp->descr_block_virt->rcv_data[i+j].long_0 = (u32) (PI_RCV_DESCR_M_SOP |
                                ((PI_RCV_DATA_K_SIZE_MAX / PI_ALIGN_K_RCV_DATA_BUFF) << PI_RCV_DESCR_V_SEG_LEN));
                        newskb = dev_alloc_skb(NEW_SKB_SIZE);
                        /*
                         * align to 128 bytes for compatibility with
                         * the old EISA boards.
                         */
                         
                        my_skb_align(newskb,128);
                        bp->descr_block_virt->rcv_data[i+j].long_1 = virt_to_bus(newskb->data);
                        /*
                         * p_rcv_buff_va is only used inside the
                         * kernel so we put the skb pointer here.
                         */
                        bp->p_rcv_buff_va[i+j] = (char *) newskb;
                }
#else
        for (i=0; i < (int)(bp->rcv_bufs_to_post); i++)
                for (j=0; (i + j) < (int)PI_RCV_DATA_K_NUM_ENTRIES; j += bp->rcv_bufs_to_post)
                        {
                        bp->descr_block_virt->rcv_data[i+j].long_0 = (u32) (PI_RCV_DESCR_M_SOP |
                                ((PI_RCV_DATA_K_SIZE_MAX / PI_ALIGN_K_RCV_DATA_BUFF) << PI_RCV_DESCR_V_SEG_LEN));
                        bp->descr_block_virt->rcv_data[i+j].long_1 = (u32) (bp->rcv_block_phys + (i * PI_RCV_DATA_K_SIZE_MAX));
                        bp->p_rcv_buff_va[i+j] = (char *) (bp->rcv_block_virt + (i * PI_RCV_DATA_K_SIZE_MAX));
                        }
#endif

        /* Update receive producer and Type 2 register */

        bp->rcv_xmt_reg.index.rcv_prod = bp->rcv_bufs_to_post;
        dfx_port_write_long(bp, PI_PDQ_K_REG_TYPE_2_PROD, bp->rcv_xmt_reg.lword);
        return;
        }

\f
/*
 * =========================
 * = dfx_rcv_queue_process =
 * =========================
 *   
 * Overview:
 *   Process received LLC frames.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   Received LLC frames are processed until there are no more consumed frames.
 *   Once all frames are processed, the receive buffers are returned to the
 *   adapter.  Note that this algorithm fixes the length of time that can be spent
 *   in this routine, because there are a fixed number of receive buffers to
 *   process and buffers are not produced until this routine exits and returns
 *   to the ISR.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   None
 *
 * Side Effects:
 *   None
 */

void dfx_rcv_queue_process(
        DFX_board_t *bp
        )

        {
        PI_TYPE_2_CONSUMER      *p_type_2_cons;         /* ptr to rcv/xmt consumer block register */
        char                            *p_buff;                        /* ptr to start of packet receive buffer (FMC descriptor) */
        u32                                     descr, pkt_len;         /* FMC descriptor field and packet length */
        struct sk_buff          *skb;                           /* pointer to a sk_buff to hold incoming packet data */

        /* Service all consumed LLC receive frames */

        p_type_2_cons = (PI_TYPE_2_CONSUMER *)(&bp->cons_block_virt->xmt_rcv_data);
        while (bp->rcv_xmt_reg.index.rcv_comp != p_type_2_cons->index.rcv_cons)
                {
                /* Process any errors */

                int entry;

                entry = bp->rcv_xmt_reg.index.rcv_comp;
#ifdef DYNAMIC_BUFFERS
                p_buff = (char *) (((struct sk_buff *)bp->p_rcv_buff_va[entry])->data);
#else
                p_buff = (char *) bp->p_rcv_buff_va[entry];
#endif
                memcpy(&descr, p_buff + RCV_BUFF_K_DESCR, sizeof(u32));

                if (descr & PI_FMC_DESCR_M_RCC_FLUSH)
                        {
                        if (descr & PI_FMC_DESCR_M_RCC_CRC)
                                bp->rcv_crc_errors++;
                        else
                                bp->rcv_frame_status_errors++;
                        }
                else
                {
                        int rx_in_place = 0;

                        /* The frame was received without errors - verify packet length */

                        pkt_len = (u32)((descr & PI_FMC_DESCR_M_LEN) >> PI_FMC_DESCR_V_LEN);
                        pkt_len -= 4;                           /* subtract 4 byte CRC */
                        if (!IN_RANGE(pkt_len, FDDI_K_LLC_ZLEN, FDDI_K_LLC_LEN))
                                bp->rcv_length_errors++;
                        else{
#ifdef DYNAMIC_BUFFERS
                                if (pkt_len > SKBUFF_RX_COPYBREAK) {
                                        struct sk_buff *newskb;

                                        newskb = dev_alloc_skb(NEW_SKB_SIZE);
                                        if (newskb){
                                                rx_in_place = 1;
                                                
                                                my_skb_align(newskb, 128);
                                                skb = (struct sk_buff *)bp->p_rcv_buff_va[entry];
                                                skb_reserve(skb, RCV_BUFF_K_PADDING);
                                                bp->p_rcv_buff_va[entry] = (char *)newskb;
                                                bp->descr_block_virt->rcv_data[entry].long_1 = virt_to_bus(newskb->data);
                                        } else
                                                skb = 0;
                                } else
#endif
                                        skb = dev_alloc_skb(pkt_len+3); /* alloc new buffer to pass up, add room for PRH */
                                if (skb == NULL)
                                        {
                                        printk("%s: Could not allocate receive buffer.  Dropping packet.\n", bp->dev->name);
                                        bp->rcv_discards++;
                                        break;
                                        }
                                else {
#ifndef DYNAMIC_BUFFERS
                                        if (! rx_in_place)
#endif
                                        {
                                                /* Receive buffer allocated, pass receive packet up */

                                                memcpy(skb->data, p_buff + RCV_BUFF_K_PADDING, pkt_len+3);
                                        }
                                        
                                        skb_reserve(skb,3);             /* adjust data field so that it points to FC byte */
                                        skb_put(skb, pkt_len);          /* pass up packet length, NOT including CRC */
                                        skb->dev = bp->dev;             /* pass up device pointer */

                                        skb->protocol = fddi_type_trans(skb, bp->dev);
                                        netif_rx(skb);

                                        /* Update the rcv counters */

                                        bp->rcv_total_frames++;
                                        if (*(p_buff + RCV_BUFF_K_DA) & 0x01)
                                                bp->rcv_multicast_frames++;
                                 
                                        bp->rcv_total_bytes += skb->len;
                                }
                        }
                        }

                /*
                 * Advance the producer (for recycling) and advance the completion
                 * (for servicing received frames).  Note that it is okay to
                 * advance the producer without checking that it passes the
                 * completion index because they are both advanced at the same
                 * rate.
                 */

                bp->rcv_xmt_reg.index.rcv_prod += 1;
                bp->rcv_xmt_reg.index.rcv_comp += 1;
                }
        return;
        }

\f
/*
 * =====================
 * = dfx_xmt_queue_pkt =
 * =====================
 *   
 * Overview:
 *   Queues packets for transmission
 *  
 * Returns:
 *   Condition code
 *       
 * Arguments:
 *   skb - pointer to sk_buff to queue for transmission
 *   dev - pointer to device information
 *
 * Functional Description:
 *   Here we assume that an incoming skb transmit request
 *   is contained in a single physically contiguous buffer
 *   in which the virtual address of the start of packet
 *   (skb->data) can be converted to a physical address
 *   by using virt_to_bus().
 *
 *   Since the adapter architecture requires a three byte
 *   packet request header to prepend the start of packet,
 *   we'll write the three byte field immediately prior to
 *   the FC byte.  This assumption is valid because we've
 *   ensured that dev->hard_header_len includes three pad
 *   bytes.  By posting a single fragment to the adapter,
 *   we'll reduce the number of descriptor fetches and
 *   bus traffic needed to send the request.
 *
 *   Also, we can't free the skb until after it's been DMA'd
 *   out by the adapter, so we'll queue it in the driver and
 *   return it in dfx_xmt_done.
 *
 * Return Codes:
 *   0 - driver queued packet, link is unavailable, or skbuff was bad
 *       1 - caller should requeue the sk_buff for later transmission
 *
 * Assumptions:
 *       First and foremost, we assume the incoming skb pointer
 *   is NOT NULL and is pointing to a valid sk_buff structure.
 *
 *   The outgoing packet is complete, starting with the
 *   frame control byte including the last byte of data,
 *   but NOT including the 4 byte CRC.  We'll let the
 *   adapter hardware generate and append the CRC.
 *
 *   The entire packet is stored in one physically
 *   contiguous buffer which is not cached and whose
 *   32-bit physical address can be determined.
 *
 *   It's vital that this routine is NOT reentered for the
 *   same board and that the OS is not in another section of
 *   code (eg. dfx_int_common) for the same board on a
 *   different thread.
 *
 * Side Effects:
 *   None
 */

int dfx_xmt_queue_pkt(
        struct sk_buff  *skb,
        struct net_device       *dev
        )

        {
        DFX_board_t             *bp = (DFX_board_t *) dev->priv;
        u8                      prod;                           /* local transmit producer index */
        PI_XMT_DESCR            *p_xmt_descr;           /* ptr to transmit descriptor block entry */
        XMT_DRIVER_DESCR        *p_xmt_drv_descr;       /* ptr to transmit driver descriptor */
        unsigned long           flags;

        /*
         * Verify that incoming transmit request is OK
         *
         * Note: The packet size check is consistent with other
         *               Linux device drivers, although the correct packet
         *               size should be verified before calling the
         *               transmit routine.
         */

        if (!IN_RANGE(skb->len, FDDI_K_LLC_ZLEN, FDDI_K_LLC_LEN))
        {
                printk("%s: Invalid packet length - %u bytes\n", 
                        dev->name, skb->len);
                bp->xmt_length_errors++;                /* bump error counter */
                mark_bh(NET_BH);
                dev_kfree_skb(skb);
                return(0);                              /* return "success" */
        }
        /*
         * See if adapter link is available, if not, free buffer
         *
         * Note: If the link isn't available, free buffer and return 0
         *               rather than tell the upper layer to requeue the packet.
         *               The methodology here is that by the time the link
         *               becomes available, the packet to be sent will be
         *               fairly stale.  By simply dropping the packet, the
         *               higher layer protocols will eventually time out
         *               waiting for response packets which it won't receive.
         */

        if (bp->link_available == PI_K_FALSE)
                {
                if (dfx_hw_adap_state_rd(bp) == PI_STATE_K_LINK_AVAIL)  /* is link really available? */
                        bp->link_available = PI_K_TRUE;         /* if so, set flag and continue */
                else
                        {
                        bp->xmt_discards++;                                     /* bump error counter */
                        dev_kfree_skb(skb);             /* free sk_buff now */
                        return(0);                                                      /* return "success" */
                        }
                }

        spin_lock_irqsave(&bp->lock, flags);
        
        /* Get the current producer and the next free xmt data descriptor */

        prod            = bp->rcv_xmt_reg.index.xmt_prod;
        p_xmt_descr = &(bp->descr_block_virt->xmt_data[prod]);

        /*
         * Get pointer to auxiliary queue entry to contain information
         * for this packet.
         *
         * Note: The current xmt producer index will become the
         *       current xmt completion index when we complete this
         *       packet later on.  So, we'll get the pointer to the
         *       next auxiliary queue entry now before we bump the
         *       producer index.
         */

        p_xmt_drv_descr = &(bp->xmt_drv_descr_blk[prod++]);     /* also bump producer index */

        /* Write the three PRH bytes immediately before the FC byte */

        skb_push(skb,3);
        skb->data[0] = DFX_PRH0_BYTE;   /* these byte values are defined */
        skb->data[1] = DFX_PRH1_BYTE;   /* in the Motorola FDDI MAC chip */
        skb->data[2] = DFX_PRH2_BYTE;   /* specification */

        /*
         * Write the descriptor with buffer info and bump producer
         *
         * Note: Since we need to start DMA from the packet request
         *               header, we'll add 3 bytes to the DMA buffer length,
         *               and we'll determine the physical address of the
         *               buffer from the PRH, not skb->data.
         *
         * Assumptions:
         *               1. Packet starts with the frame control (FC) byte
         *                  at skb->data.
         *               2. The 4-byte CRC is not appended to the buffer or
         *                      included in the length.
         *               3. Packet length (skb->len) is from FC to end of
         *                      data, inclusive.
         *               4. The packet length does not exceed the maximum
         *                      FDDI LLC frame length of 4491 bytes.
         *               5. The entire packet is contained in a physically
         *                      contiguous, non-cached, locked memory space
         *                      comprised of a single buffer pointed to by
         *                      skb->data.
         *               6. The physical address of the start of packet
         *                      can be determined from the virtual address
         *                      by using virt_to_bus() and is only 32-bits
         *                      wide.
         */

        p_xmt_descr->long_0     = (u32) (PI_XMT_DESCR_M_SOP | PI_XMT_DESCR_M_EOP | ((skb->len) << PI_XMT_DESCR_V_SEG_LEN));
        p_xmt_descr->long_1 = (u32) virt_to_bus(skb->data);

        /*
         * Verify that descriptor is actually available
         *
         * Note: If descriptor isn't available, return 1 which tells
         *       the upper layer to requeue the packet for later
         *       transmission.
         *
         *       We need to ensure that the producer never reaches the
         *       completion, except to indicate that the queue is empty.
         */

        if (prod == bp->rcv_xmt_reg.index.xmt_comp)
        {
                skb_pull(skb,3);
                spin_unlock_irqrestore(&bp->lock, flags);
                return(1);                      /* requeue packet for later */
        }

        /*
         * Save info for this packet for xmt done indication routine
         *
         * Normally, we'd save the producer index in the p_xmt_drv_descr
         * structure so that we'd have it handy when we complete this
         * packet later (in dfx_xmt_done).  However, since the current
         * transmit architecture guarantees a single fragment for the
         * entire packet, we can simply bump the completion index by
         * one (1) for each completed packet.
         *
         * Note: If this assumption changes and we're presented with
         *       an inconsistent number of transmit fragments for packet
         *       data, we'll need to modify this code to save the current
         *       transmit producer index.
         */

        p_xmt_drv_descr->p_skb = skb;

        /* Update Type 2 register */

        bp->rcv_xmt_reg.index.xmt_prod = prod;
        dfx_port_write_long(bp, PI_PDQ_K_REG_TYPE_2_PROD, bp->rcv_xmt_reg.lword);
        spin_unlock_irqrestore(&bp->lock, flags);
        return(0);                                                      /* packet queued to adapter */
        }

\f
/*
 * ================
 * = dfx_xmt_done =
 * ================
 *   
 * Overview:
 *   Processes all frames that have been transmitted.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   For all consumed transmit descriptors that have not
 *   yet been completed, we'll free the skb we were holding
 *   onto using dev_kfree_skb and bump the appropriate
 *   counters.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   The Type 2 register is not updated in this routine.  It is
 *   assumed that it will be updated in the ISR when dfx_xmt_done
 *   returns.
 *
 * Side Effects:
 *   None
 */

void dfx_xmt_done(
        DFX_board_t *bp
        )

        {
        XMT_DRIVER_DESCR        *p_xmt_drv_descr;       /* ptr to transmit driver descriptor */
        PI_TYPE_2_CONSUMER      *p_type_2_cons;         /* ptr to rcv/xmt consumer block register */

        /* Service all consumed transmit frames */

        p_type_2_cons = (PI_TYPE_2_CONSUMER *)(&bp->cons_block_virt->xmt_rcv_data);
        while (bp->rcv_xmt_reg.index.xmt_comp != p_type_2_cons->index.xmt_cons)
                {
                /* Get pointer to the transmit driver descriptor block information */

                p_xmt_drv_descr = &(bp->xmt_drv_descr_blk[bp->rcv_xmt_reg.index.xmt_comp]);

                /* Increment transmit counters */

                bp->xmt_total_frames++;
                bp->xmt_total_bytes += p_xmt_drv_descr->p_skb->len;

                /* Return skb to operating system */

                dev_kfree_skb(p_xmt_drv_descr->p_skb);

                /*
                 * Move to start of next packet by updating completion index
                 *
                 * Here we assume that a transmit packet request is always
                 * serviced by posting one fragment.  We can therefore
                 * simplify the completion code by incrementing the
                 * completion index by one.  This code will need to be
                 * modified if this assumption changes.  See comments
                 * in dfx_xmt_queue_pkt for more details.
                 */

                bp->rcv_xmt_reg.index.xmt_comp += 1;
                }
        return;
        }

\f
/*
 * =================
 * = dfx_xmt_flush =
 * =================
 *   
 * Overview:
 *   Processes all frames whether they've been transmitted
 *   or not.
 *  
 * Returns:
 *   None
 *       
 * Arguments:
 *   bp - pointer to board information
 *
 * Functional Description:
 *   For all produced transmit descriptors that have not
 *   yet been completed, we'll free the skb we were holding
 *   onto using dev_kfree_skb and bump the appropriate
 *   counters.  Of course, it's possible that some of
 *   these transmit requests actually did go out, but we
 *   won't make that distinction here.  Finally, we'll
 *   update the consumer index to match the producer.
 *
 * Return Codes:
 *   None
 *
 * Assumptions:
 *   This routine does NOT update the Type 2 register.  It
 *   is assumed that this routine is being called during a
 *   transmit flush interrupt, or a shutdown or close routine.
 *
 * Side Effects:
 *   None
 */

void dfx_xmt_flush(
        DFX_board_t *bp
        )

        {
        u32                                     prod_cons;                      /* rcv/xmt consumer block longword */
        XMT_DRIVER_DESCR        *p_xmt_drv_descr;       /* ptr to transmit driver descriptor */

        /* Flush all outstanding transmit frames */

        while (bp->rcv_xmt_reg.index.xmt_comp != bp->rcv_xmt_reg.index.xmt_prod)
                {
                /* Get pointer to the transmit driver descriptor block information */

                p_xmt_drv_descr = &(bp->xmt_drv_descr_blk[bp->rcv_xmt_reg.index.xmt_comp]);

                /* Return skb to operating system */

                dev_kfree_skb(p_xmt_drv_descr->p_skb);

                /* Increment transmit error counter */

                bp->xmt_discards++;

                /*
                 * Move to start of next packet by updating completion index
                 *
                 * Here we assume that a transmit packet request is always
                 * serviced by posting one fragment.  We can therefore
                 * simplify the completion code by incrementing the
                 * completion index by one.  This code will need to be
                 * modified if this assumption changes.  See comments
                 * in dfx_xmt_queue_pkt for more details.
                 */

                bp->rcv_xmt_reg.index.xmt_comp += 1;
                }

        /* Update the transmit consumer index in the consumer block */

        prod_cons = (u32)(bp->cons_block_virt->xmt_rcv_data & ~PI_CONS_M_XMT_INDEX);
        prod_cons |= (u32)(bp->rcv_xmt_reg.index.xmt_prod << PI_CONS_V_XMT_INDEX);
        bp->cons_block_virt->xmt_rcv_data = prod_cons;
        return;
        }

\f
/*
 * Local variables:
 * kernel-compile-command: "gcc -D__KERNEL__ -I/root/linux/include -Wall -Wstrict-prototypes -O2 -pipe -fomit-frame-pointer -fno-strength-reduce -m486 -malign-loops=2 -malign-jumps=2 -malign-functions=2 -DCPU=586 -c defxx.c"
 * End:
 */