src/hardware/ne2000.cpp

#include "config.h"

#if C_NE2000

#if defined(WIN32)
  #define HAVE_REMOTE
#endif

#include "dosbox.h"
#include <string.h>
#include <stdio.h>
#include "support.h"
#include "inout.h"
#include "setup.h"
#include "callback.h"
#include "timer.h"
#include "pic.h"
#include "cpu.h"
#include "setup.h"
#include "control.h"

/* Couldn't find a real spec for the NE2000 out there, hence this is adapted heavily from Bochs */


// $Id: ne2k.cc,v 1.56.2.1 2004/02/02 22:37:22 cbothamy Exp $
//
//  Copyright (C) 2002  MandrakeSoft S.A.
//
//    MandrakeSoft S.A.
//    43, rue d'Aboukir
//    75002 Paris - France
//    http://www.linux-mandrake.com/
//    http://www.mandrakesoft.com/
//
//  This library is free software; you can redistribute it and/or
//  modify it under the terms of the GNU Lesser General Public
//  License as published by the Free Software Foundation; either
//  version 2 of the License, or (at your option) any later version.
//
//  This library is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
//  Lesser General Public License for more details.
//
//  You should have received a copy of the GNU General Public License along
//  with this program; if not, write to the Free Software Foundation, Inc.,
//  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

// Peter Grehan (grehan@iprg.nokia.com) coded all of this
// NE2000/ether stuff.

#include "ne2000.h"

#include "pcap.h"
// Handle to WinPCap device
pcap_t *adhandle = 0;
static void NE2000_TX_Event(Bitu val);

#ifdef WIN32
// DLL loading
#define pcap_sendpacket(A,B,C)                  PacketSendPacket(A,B,C)
#define pcap_close(A)                                   PacketClose(A)
#define pcap_freealldevs(A)                             PacketFreealldevs(A)
#define pcap_open(A,B,C,D,E,F)                  PacketOpen(A,B,C,D,E,F)
#define pcap_next_ex(A,B,C)                             PacketNextEx(A,B,C)
#define pcap_findalldevs_ex(A,B,C,D)    PacketFindALlDevsEx(A,B,C,D)

int (*PacketSendPacket)(pcap_t *, const u_char *, int) = 0;
void (*PacketClose)(pcap_t *) = 0;
void (*PacketFreealldevs)(pcap_if_t *) = 0;
pcap_t* (*PacketOpen)(char const *,int,int,int,struct pcap_rmtauth *,char *) = 0;
int (*PacketNextEx)(pcap_t *, struct pcap_pkthdr **, const u_char **) = 0;
int (*PacketFindALlDevsEx)(char *, struct pcap_rmtauth *, pcap_if_t **, char *) = 0;

#endif

//Never completely fill the ne2k ring so that we never
// hit the unclear completely full buffer condition.
#define BX_NE2K_NEVER_FULL_RING (1)

#define LOG_THIS theNE2kDevice->
//#define BX_DEBUG 
//#define BX_INFO 
#define BX_NULL_TIMER_HANDLE 0
//#define BX_PANIC 
//#define BX_ERROR 
#define BX_RESET_HARDWARE 0
#define BX_RESET_SOFTWARE 1

static char bxtmp[1024];

static inline void BX_INFO(const char *msg,...) {
    va_list va;

    va_start(va,msg);
    vsnprintf(bxtmp,sizeof(bxtmp)-1,msg,va);
    va_end(va);

    LOG(LOG_MISC,LOG_NORMAL)("BX_INFO: %s",bxtmp);
}

static inline void BX_DEBUG(const char *msg,...) {
    if (false/*TOO MUCH DEBUG INFO*/) {
        va_list va;

        va_start(va,msg);
        vsnprintf(bxtmp,sizeof(bxtmp)-1,msg,va);
        va_end(va);

        LOG(LOG_MISC,LOG_DEBUG)("BX_DEBUG: %s",bxtmp);
    }
}

static inline void BX_ERROR(const char *msg,...) {
    va_list va;

    va_start(va,msg);
    vsnprintf(bxtmp,sizeof(bxtmp)-1,msg,va);
    va_end(va);

    LOG_MSG("BX_ERROR: %s",bxtmp);
}

static inline void BX_PANIC(const char *msg,...) {
    va_list va;

    va_start(va,msg);
    vsnprintf(bxtmp,sizeof(bxtmp)-1,msg,va);
    va_end(va);

    LOG_MSG("BX_PANIC: %s",bxtmp);
    E_Exit("BX_PANIC condition");
}

bx_ne2k_c* theNE2kDevice = NULL;

  
bx_ne2k_c::bx_ne2k_c(void)
{
  s.tx_timer_index = BX_NULL_TIMER_HANDLE;
}


bx_ne2k_c::~bx_ne2k_c(void)
{
  // nothing for now
}

//
// reset - restore state to power-up, cancelling all i/o
//
void
bx_ne2k_c::reset(unsigned type)
{
    (void)type;//UNUSED
  BX_DEBUG ("reset");
  // Zero out registers and memory
  memset( & BX_NE2K_THIS s.CR,  0, sizeof(BX_NE2K_THIS s.CR) );
  memset( & BX_NE2K_THIS s.ISR, 0, sizeof(BX_NE2K_THIS s.ISR));
  memset( & BX_NE2K_THIS s.IMR, 0, sizeof(BX_NE2K_THIS s.IMR));
  memset( & BX_NE2K_THIS s.DCR, 0, sizeof(BX_NE2K_THIS s.DCR));
  memset( & BX_NE2K_THIS s.TCR, 0, sizeof(BX_NE2K_THIS s.TCR));
  memset( & BX_NE2K_THIS s.TSR, 0, sizeof(BX_NE2K_THIS s.TSR));
  //memset( & BX_NE2K_THIS s.RCR, 0, sizeof(BX_NE2K_THIS s.RCR));
  memset( & BX_NE2K_THIS s.RSR, 0, sizeof(BX_NE2K_THIS s.RSR));
  BX_NE2K_THIS s.tx_timer_active = 0;
  BX_NE2K_THIS s.local_dma  = 0;
  BX_NE2K_THIS s.page_start = 0;
  BX_NE2K_THIS s.page_stop  = 0;
  BX_NE2K_THIS s.bound_ptr  = 0;
  BX_NE2K_THIS s.tx_page_start = 0;
  BX_NE2K_THIS s.num_coll   = 0;
  BX_NE2K_THIS s.tx_bytes   = 0;
  BX_NE2K_THIS s.fifo       = 0;
  BX_NE2K_THIS s.remote_dma = 0;
  BX_NE2K_THIS s.remote_start = 0;
  BX_NE2K_THIS s.remote_bytes = 0;
  BX_NE2K_THIS s.tallycnt_0 = 0;
  BX_NE2K_THIS s.tallycnt_1 = 0;
  BX_NE2K_THIS s.tallycnt_2 = 0;

  //memset( & BX_NE2K_THIS s.physaddr, 0, sizeof(BX_NE2K_THIS s.physaddr));
  //memset( & BX_NE2K_THIS s.mchash, 0, sizeof(BX_NE2K_THIS s.mchash));
  BX_NE2K_THIS s.curr_page = 0;

  BX_NE2K_THIS s.rempkt_ptr   = 0;
  BX_NE2K_THIS s.localpkt_ptr = 0;
  BX_NE2K_THIS s.address_cnt  = 0;

  memset( & BX_NE2K_THIS s.mem, 0, sizeof(BX_NE2K_THIS s.mem));
  
  // Set power-up conditions
  BX_NE2K_THIS s.CR.stop      = 1;
    BX_NE2K_THIS s.CR.rdma_cmd  = 4;
  BX_NE2K_THIS s.ISR.reset    = 1;
  BX_NE2K_THIS s.DCR.longaddr = 1;
  PIC_DeActivateIRQ((unsigned int)s.base_irq);
  //DEV_pic_lower_irq(BX_NE2K_THIS s.base_irq);
}

//
// read_cr/write_cr - utility routines for handling reads/writes to
// the Command Register
//
Bit32u
bx_ne2k_c::read_cr(void)
{
  Bit32u val = 
    (((unsigned int)(BX_NE2K_THIS s.CR.pgsel    & 0x03u) << 6u) |
         ((unsigned int)(BX_NE2K_THIS s.CR.rdma_cmd & 0x07u) << 3u) |
          (unsigned int)(BX_NE2K_THIS s.CR.tx_packet << 2u) |
          (unsigned int)(BX_NE2K_THIS s.CR.start     << 1u) |
          (unsigned int)(BX_NE2K_THIS s.CR.stop));
  BX_DEBUG("read CR returns 0x%08x", val);
  return val;
}

void
bx_ne2k_c::write_cr(Bit32u value)
{
  BX_DEBUG ("wrote 0x%02x to CR", value);

  // Validate remote-DMA
  if ((value & 0x38) == 0x00) {
    BX_DEBUG("CR write - invalid rDMA value 0");
    value |= 0x20; /* dma_cmd == 4 is a safe default */
        //value = 0x22; /* dma_cmd == 4 is a safe default */
  }

  // Check for s/w reset
  if (value & 0x01) {
    BX_NE2K_THIS s.ISR.reset = 1;
    BX_NE2K_THIS s.CR.stop   = 1;
  } else {
    BX_NE2K_THIS s.CR.stop = 0;
  }

  BX_NE2K_THIS s.CR.rdma_cmd = (value & 0x38) >> 3;
  
  // If start command issued, the RST bit in the ISR
  // must be cleared
  if ((value & 0x02) && !BX_NE2K_THIS s.CR.start) {
    BX_NE2K_THIS s.ISR.reset = 0;
  }

  BX_NE2K_THIS s.CR.start = ((value & 0x02) == 0x02);
  BX_NE2K_THIS s.CR.pgsel = (value & 0xc0) >> 6;

    // Check for send-packet command
    if (BX_NE2K_THIS s.CR.rdma_cmd == 3) {
        // Set up DMA read from receive ring
                BX_NE2K_THIS s.remote_start = BX_NE2K_THIS s.remote_dma =
                        BX_NE2K_THIS s.bound_ptr * 256;
                BX_NE2K_THIS s.remote_bytes = *((Bit16u*) &
                        BX_NE2K_THIS s.mem[BX_NE2K_THIS s.bound_ptr * 256 + 2 - BX_NE2K_MEMSTART]);
                BX_INFO("Sending buffer #x%x length %d",
                        BX_NE2K_THIS s.remote_start,
                        BX_NE2K_THIS s.remote_bytes);
    }

  // Check for start-tx
    if ((value & 0x04) && BX_NE2K_THIS s.TCR.loop_cntl) {
                // loopback mode
                if (BX_NE2K_THIS s.TCR.loop_cntl != 1) {
                        BX_INFO("Loop mode %d not supported.", BX_NE2K_THIS s.TCR.loop_cntl);
                } else {
                        rx_frame (& BX_NE2K_THIS s.mem[BX_NE2K_THIS s.tx_page_start*256 -
                                BX_NE2K_MEMSTART],
                                BX_NE2K_THIS s.tx_bytes);

                        // do a TX interrupt
                        // Generate an interrupt if not masked and not one in progress
                        if (BX_NE2K_THIS s.IMR.tx_inte && !BX_NE2K_THIS s.ISR.pkt_tx) {
                                //LOG_MSG("tx complete interrupt");
                                PIC_ActivateIRQ((unsigned int)s.base_irq);
                        }
                        BX_NE2K_THIS s.ISR.pkt_tx = 1;
                }
    } else if (value & 0x04) {
                // start-tx and no loopback
                if (BX_NE2K_THIS s.CR.stop || !BX_NE2K_THIS s.CR.start)
                        BX_PANIC(("CR write - tx start, dev in reset"));
            
                if (BX_NE2K_THIS s.tx_bytes == 0)
                        BX_PANIC(("CR write - tx start, tx bytes == 0"));

#ifdef notdef    
    // XXX debug stuff
    printf("packet tx (%d bytes):\t", BX_NE2K_THIS s.tx_bytes);
    for (int i = 0; i < BX_NE2K_THIS s.tx_bytes; i++) {
      printf("%02x ", BX_NE2K_THIS s.mem[BX_NE2K_THIS s.tx_page_start*256 - 
                                BX_NE2K_MEMSTART + i]);
      if (i && (((i+1) % 16) == 0)) 
        printf("\t");
    }
    printf("");
#endif    

    // Send the packet to the system driver
        /* TODO: Transmit packet */
    //BX_NE2K_THIS ethdev->sendpkt(& BX_NE2K_THIS s.mem[BX_NE2K_THIS s.tx_page_start*256 - BX_NE2K_MEMSTART], BX_NE2K_THIS s.tx_bytes);
        pcap_sendpacket(adhandle,&s.mem[s.tx_page_start*256 - BX_NE2K_MEMSTART], s.tx_bytes);
        // some more debug
        if (BX_NE2K_THIS s.tx_timer_active) {
      BX_PANIC(("CR write, tx timer still active"));
          PIC_RemoveEvents(NE2000_TX_Event);
        }
        //LOG_MSG("send packet command");
        //s.tx_timer_index = (64 + 96 + 4*8 + BX_NE2K_THIS s.tx_bytes*8)/10;
        s.tx_timer_active = 1;
        PIC_AddEvent(NE2000_TX_Event,(float)((64 + 96 + 4*8 + BX_NE2K_THIS s.tx_bytes*8)/10000.0),0);
    // Schedule a timer to trigger a tx-complete interrupt
    // The number of microseconds is the bit-time / 10.
    // The bit-time is the preamble+sfd (64 bits), the
    // inter-frame gap (96 bits), the CRC (4 bytes), and the
    // the number of bits in the frame (s.tx_bytes * 8).
    //

        /* TODO: Code transmit timer */
        /*
    bx_pc_system.activate_timer(BX_NE2K_THIS s.tx_timer_index,
                                (64 + 96 + 4*8 + BX_NE2K_THIS s.tx_bytes*8)/10,
                                0); // not continuous
        */
  } // end transmit-start branch

  // Linux probes for an interrupt by setting up a remote-DMA read
  // of 0 bytes with remote-DMA completion interrupts enabled.
  // Detect this here
  if (BX_NE2K_THIS s.CR.rdma_cmd == 0x01 &&
      BX_NE2K_THIS s.CR.start &&
      BX_NE2K_THIS s.remote_bytes == 0) {
    BX_NE2K_THIS s.ISR.rdma_done = 1;
    if (BX_NE2K_THIS s.IMR.rdma_inte) {
                PIC_ActivateIRQ((unsigned int)s.base_irq);
      //DEV_pic_raise_irq(BX_NE2K_THIS s.base_irq);
    }
  }
}

//
// chipmem_read/chipmem_write - access the 64K private RAM.
// The ne2000 memory is accessed through the data port of
// the asic (offset 0) after setting up a remote-DMA transfer.
// Both byte and word accesses are allowed.
// The first 16 bytes contains the MAC address at even locations,
// and there is 16K of buffer memory starting at 16K
//
Bit32u bx_ne2k_c::chipmem_read(Bit32u address, unsigned int io_len)
{
  Bit32u retval = 0;

  if ((io_len == 2) && (address & 0x1)) 
    BX_PANIC(("unaligned chipmem word read"));

  // ROM'd MAC address
  if (/*(address >=0) && */address <= 31) {
    retval = BX_NE2K_THIS s.macaddr[address];
    if ((io_len == 2u) || (io_len == 4u)) {
      retval |= (unsigned int)(BX_NE2K_THIS s.macaddr[address + 1u] << 8u);
          if (io_len == 4u) {
                        retval |= (unsigned int)(BX_NE2K_THIS s.macaddr[address + 2u] << 16u);
                        retval |= (unsigned int)(BX_NE2K_THIS s.macaddr[address + 3u] << 24u);
          }
    }
    return (retval);
  }

  if ((address >= BX_NE2K_MEMSTART) && (address < BX_NE2K_MEMEND)) {
    retval = BX_NE2K_THIS s.mem[address - BX_NE2K_MEMSTART];
    if ((io_len == 2u) || (io_len == 4u)) {
      retval |= (unsigned int)(BX_NE2K_THIS s.mem[address - BX_NE2K_MEMSTART + 1] << 8u);
    }
        if (io_len == 4u) {
       retval |= (unsigned int)(BX_NE2K_THIS s.mem[address - BX_NE2K_MEMSTART + 2] << 16u);
       retval |= (unsigned int)(BX_NE2K_THIS s.mem[address - BX_NE2K_MEMSTART + 3] << 24u);
    }
    return (retval);
  }

  BX_DEBUG("out-of-bounds chipmem read, %04X", address);

  return (0xff);
}

void 
bx_ne2k_c::chipmem_write(Bit32u address, Bit32u value, unsigned io_len)
{
  if ((io_len == 2) && (address & 0x1)) 
    BX_PANIC(("unaligned chipmem word write"));

  if ((address >= BX_NE2K_MEMSTART) && (address < BX_NE2K_MEMEND)) {
    BX_NE2K_THIS s.mem[address - BX_NE2K_MEMSTART] = value & 0xff;
    if (io_len == 2)
      BX_NE2K_THIS s.mem[address - BX_NE2K_MEMSTART + 1] = value >> 8;
  } else
    BX_DEBUG("out-of-bounds chipmem write, %04X", address);
}

//
// asic_read/asic_write - This is the high 16 bytes of i/o space
// (the lower 16 bytes is for the DS8390). Only two locations
// are used: offset 0, which is used for data transfer, and
// offset 0xf, which is used to reset the device.
// The data transfer port is used to as 'external' DMA to the
// DS8390. The chip has to have the DMA registers set up, and
// after that, insw/outsw instructions can be used to move
// the appropriate number of bytes to/from the device.
//
Bit32u 
bx_ne2k_c::asic_read(Bit32u offset, unsigned int io_len)
{
  Bit32u retval = 0;

  switch (offset) {
  case 0x0:  // Data register
    //
    // A read remote-DMA command must have been issued,
    // and the source-address and length registers must  
    // have been initialised.
    //
    if (io_len > BX_NE2K_THIS s.remote_bytes)
      {
       BX_ERROR("ne2K: dma read underrun iolen=%d remote_bytes=%d",io_len,BX_NE2K_THIS s.remote_bytes);
       //return 0;
      }

    //BX_INFO(("ne2k read DMA: addr=%4x remote_bytes=%d",BX_NE2K_THIS s.remote_dma,BX_NE2K_THIS s.remote_bytes));
    retval = chipmem_read(BX_NE2K_THIS s.remote_dma, io_len);
    //
    // The 8390 bumps the address and decreases the byte count
    // by the selected word size after every access, not by
    // the amount of data requested by the host (io_len).
    //
    BX_NE2K_THIS s.remote_dma += (BX_NE2K_THIS s.DCR.wdsize + 1);
    if (BX_NE2K_THIS s.remote_dma == BX_NE2K_THIS s.page_stop << 8) {
      BX_NE2K_THIS s.remote_dma = BX_NE2K_THIS s.page_start << 8;
    }
    // keep s.remote_bytes from underflowing
    if (BX_NE2K_THIS s.remote_bytes > 1)
      BX_NE2K_THIS s.remote_bytes -= (BX_NE2K_THIS s.DCR.wdsize + 1);
    else
      BX_NE2K_THIS s.remote_bytes = 0;

        // If all bytes have been written, signal remote-DMA complete
        if (BX_NE2K_THIS s.remote_bytes == 0) {
            BX_NE2K_THIS s.ISR.rdma_done = 1;
            if (BX_NE2K_THIS s.IMR.rdma_inte) {
                        PIC_ActivateIRQ((unsigned int)s.base_irq);
                //DEV_pic_raise_irq(BX_NE2K_THIS s.base_irq);
                }
        }
    break;

  case 0xf:  // Reset register
    theNE2kDevice->reset(BX_RESET_SOFTWARE);
        //retval=0x1;
    break;

  default:
    BX_INFO("asic read invalid address %04x", (unsigned) offset);
    break;
  }

  return (retval);
}

void
bx_ne2k_c::asic_write(Bit32u offset, Bit32u value, unsigned io_len)
{
  BX_DEBUG("asic write addr=0x%02x, value=0x%04x", (unsigned) offset, (unsigned) value);
  switch (offset) {
  case 0x0:  // Data register - see asic_read for a description

    if ((io_len == 2) && (BX_NE2K_THIS s.DCR.wdsize == 0)) {
      BX_PANIC(("dma write length 2 on byte mode operation"));
      break;
    }

    if (BX_NE2K_THIS s.remote_bytes == 0)
      BX_PANIC(("ne2K: dma write, byte count 0"));

    chipmem_write(BX_NE2K_THIS s.remote_dma, value, io_len);
    // is this right ??? asic_read uses DCR.wordsize
    BX_NE2K_THIS s.remote_dma   += io_len;
    if (BX_NE2K_THIS s.remote_dma == BX_NE2K_THIS s.page_stop << 8) {
      BX_NE2K_THIS s.remote_dma = BX_NE2K_THIS s.page_start << 8;
    }

    BX_NE2K_THIS s.remote_bytes -= io_len;
    if (BX_NE2K_THIS s.remote_bytes > BX_NE2K_MEMSIZ)
      BX_NE2K_THIS s.remote_bytes = 0;

    // If all bytes have been written, signal remote-DMA complete
    if (BX_NE2K_THIS s.remote_bytes == 0) {
      BX_NE2K_THIS s.ISR.rdma_done = 1;
      if (BX_NE2K_THIS s.IMR.rdma_inte) {
          PIC_ActivateIRQ((unsigned int)s.base_irq);
          //DEV_pic_raise_irq(BX_NE2K_THIS s.base_irq);
      }
    }
    break;

  case 0xf:  // Reset register
    theNE2kDevice->reset(BX_RESET_SOFTWARE);
    break;

  default: // this is invalid, but happens under win95 device detection
    BX_INFO("asic write invalid address %04x, ignoring", (unsigned) offset);
    break ;
  }
}

//
// page0_read/page0_write - These routines handle reads/writes to
// the 'zeroth' page of the DS8390 register file
//
Bit32u
bx_ne2k_c::page0_read(Bit32u offset, unsigned int io_len)
{
  BX_DEBUG("page 0 read from port %04x, len=%u", (unsigned) offset,
           (unsigned) io_len);
  if (io_len > 1) {
    BX_ERROR("bad length! page 0 read from port %04x, len=%u", (unsigned) offset,
             (unsigned) io_len); /* encountered with win98 hardware probe */
        return 0;
  }


  switch (offset) {
  case 0x1:  // CLDA0
    return (BX_NE2K_THIS s.local_dma & 0xff);
    break;

  case 0x2:  // CLDA1
    return (unsigned int)(BX_NE2K_THIS s.local_dma >> 8u);
    break;

  case 0x3:  // BNRY
    return (BX_NE2K_THIS s.bound_ptr);
    break;

  case 0x4:  // TSR
    return
       ((unsigned int)(BX_NE2K_THIS s.TSR.ow_coll    << 7u) |
            (unsigned int)(BX_NE2K_THIS s.TSR.cd_hbeat   << 6u) |
            (unsigned int)(BX_NE2K_THIS s.TSR.fifo_ur    << 5u) |
            (unsigned int)(BX_NE2K_THIS s.TSR.no_carrier << 4u) |
            (unsigned int)(BX_NE2K_THIS s.TSR.aborted    << 3u) |
            (unsigned int)(BX_NE2K_THIS s.TSR.collided   << 2u) |
            (unsigned int)(BX_NE2K_THIS s.TSR.tx_ok));
    break;

  case 0x5:  // NCR
    return (BX_NE2K_THIS s.num_coll);
    break;
    
  case 0x6:  // FIFO
    // reading FIFO is only valid in loopback mode
    BX_ERROR(("reading FIFO not supported yet"));
    return (BX_NE2K_THIS s.fifo);
    break;

  case 0x7:  // ISR
    return
       ((unsigned int)(BX_NE2K_THIS s.ISR.reset     << 7u) |
            (unsigned int)(BX_NE2K_THIS s.ISR.rdma_done << 6u) |
            (unsigned int)(BX_NE2K_THIS s.ISR.cnt_oflow << 5u) |
            (unsigned int)(BX_NE2K_THIS s.ISR.overwrite << 4u) |
            (unsigned int)(BX_NE2K_THIS s.ISR.tx_err    << 3u) |
            (unsigned int)(BX_NE2K_THIS s.ISR.rx_err    << 2u) |
            (unsigned int)(BX_NE2K_THIS s.ISR.pkt_tx    << 1u) |
            (unsigned int)(BX_NE2K_THIS s.ISR.pkt_rx));
    break;
    
  case 0x8:  // CRDA0
    return (BX_NE2K_THIS s.remote_dma & 0xff);
    break;

  case 0x9:  // CRDA1
    return (unsigned int)(BX_NE2K_THIS s.remote_dma >> 8u);
    break;

  case 0xa:  // reserved
    BX_INFO(("reserved read - page 0, 0xa"));
    return (0xff);
    break;

  case 0xb:  // reserved
    BX_INFO(("reserved read - page 0, 0xb"));
    return (0xff);
    break;
    
  case 0xc:  // RSR
    return
       ((unsigned int)(BX_NE2K_THIS s.RSR.deferred    << 7u) |
            (unsigned int)(BX_NE2K_THIS s.RSR.rx_disabled << 6u) |
            (unsigned int)(BX_NE2K_THIS s.RSR.rx_mbit     << 5u) |
            (unsigned int)(BX_NE2K_THIS s.RSR.rx_missed   << 4u) |
            (unsigned int)(BX_NE2K_THIS s.RSR.fifo_or     << 3u) |
            (unsigned int)(BX_NE2K_THIS s.RSR.bad_falign  << 2u) |
            (unsigned int)(BX_NE2K_THIS s.RSR.bad_crc     << 1u) |
            (unsigned int)(BX_NE2K_THIS s.RSR.rx_ok));
    break;
    
  case 0xd:  // CNTR0
    return (BX_NE2K_THIS s.tallycnt_0);
    break;

  case 0xe:  // CNTR1
    return (BX_NE2K_THIS s.tallycnt_1);
    break;

  case 0xf:  // CNTR2
    return (BX_NE2K_THIS s.tallycnt_2);
    break;

  default:
    BX_PANIC("page 0 offset %04x out of range", (unsigned) offset);
  }

  return(0);
}

void
bx_ne2k_c::page0_write(Bit32u offset, Bit32u value, unsigned io_len)
{
  BX_DEBUG("page 0 write to port %04x, len=%u", (unsigned) offset,
           (unsigned) io_len);

  // It appears to be a common practice to use outw on page0 regs...

  // break up outw into two outb's
  if (io_len == 2) {
    page0_write(offset, (value & 0xff), 1);
    page0_write(offset + 1, ((value >> 8) & 0xff), 1);
    return;
  }

  switch (offset) {
  case 0x1:  // PSTART
    BX_NE2K_THIS s.page_start = value;
    break;

  case 0x2:  // PSTOP
        // BX_INFO(("Writing to PSTOP: %02x", value));
    BX_NE2K_THIS s.page_stop = value;
    break;

  case 0x3:  // BNRY
    BX_NE2K_THIS s.bound_ptr = value;
    break;

  case 0x4:  // TPSR
    BX_NE2K_THIS s.tx_page_start = value;
    break;

  case 0x5:  // TBCR0
    // Clear out low byte and re-insert
    BX_NE2K_THIS s.tx_bytes &= 0xff00;
    BX_NE2K_THIS s.tx_bytes |= (value & 0xff);
    break;

  case 0x6:  // TBCR1
    // Clear out high byte and re-insert
    BX_NE2K_THIS s.tx_bytes &= 0x00ff;
    BX_NE2K_THIS s.tx_bytes |= ((value & 0xff) << 8);
    break;

  case 0x7:  // ISR
    value &= 0x7f;  // clear RST bit - status-only bit
    // All other values are cleared iff the ISR bit is 1
    BX_NE2K_THIS s.ISR.pkt_rx    &= ~((bx_bool)((value & 0x01) == 0x01));
        BX_NE2K_THIS s.ISR.pkt_tx    &= ~((bx_bool)((value & 0x02) == 0x02));
    BX_NE2K_THIS s.ISR.rx_err    &= ~((bx_bool)((value & 0x04) == 0x04));
    BX_NE2K_THIS s.ISR.tx_err    &= ~((bx_bool)((value & 0x08) == 0x08));
    BX_NE2K_THIS s.ISR.overwrite &= ~((bx_bool)((value & 0x10) == 0x10));
    BX_NE2K_THIS s.ISR.cnt_oflow &= ~((bx_bool)((value & 0x20) == 0x20));
    BX_NE2K_THIS s.ISR.rdma_done &= ~((bx_bool)((value & 0x40) == 0x40));
    value = ((unsigned int)(BX_NE2K_THIS s.ISR.rdma_done << 6u) |
             (unsigned int)(BX_NE2K_THIS s.ISR.cnt_oflow << 5u) |
             (unsigned int)(BX_NE2K_THIS s.ISR.overwrite << 4u) |
             (unsigned int)(BX_NE2K_THIS s.ISR.tx_err    << 3u) |
             (unsigned int)(BX_NE2K_THIS s.ISR.rx_err    << 2u) |
             (unsigned int)(BX_NE2K_THIS s.ISR.pkt_tx    << 1u) |
             (unsigned int)(BX_NE2K_THIS s.ISR.pkt_rx));
    value &= ((unsigned int)(BX_NE2K_THIS s.IMR.rdma_inte  << 6u) |
              (unsigned int)(BX_NE2K_THIS s.IMR.cofl_inte  << 5u) |
              (unsigned int)(BX_NE2K_THIS s.IMR.overw_inte << 4u) |
              (unsigned int)(BX_NE2K_THIS s.IMR.txerr_inte << 3u) |
              (unsigned int)(BX_NE2K_THIS s.IMR.rxerr_inte << 2u) |
              (unsigned int)(BX_NE2K_THIS s.IMR.tx_inte    << 1u) |
              (unsigned int)(BX_NE2K_THIS s.IMR.rx_inte));
    if (value == 0)
          PIC_DeActivateIRQ((unsigned int)s.base_irq);
      //DEV_pic_lower_irq(BX_NE2K_THIS s.base_irq);
    break;

  case 0x8:  // RSAR0
    // Clear out low byte and re-insert
    BX_NE2K_THIS s.remote_start &= 0xff00u;
    BX_NE2K_THIS s.remote_start |= (value & 0xffu);
    BX_NE2K_THIS s.remote_dma = BX_NE2K_THIS s.remote_start;
    break;

  case 0x9:  // RSAR1
    // Clear out high byte and re-insert
    BX_NE2K_THIS s.remote_start &= 0x00ffu;
    BX_NE2K_THIS s.remote_start |= ((value & 0xffu) << 8u);
    BX_NE2K_THIS s.remote_dma = BX_NE2K_THIS s.remote_start;
    break;

  case 0xa:  // RBCR0
    // Clear out low byte and re-insert
    BX_NE2K_THIS s.remote_bytes &= 0xff00u;
    BX_NE2K_THIS s.remote_bytes |= (value & 0xffu);
    break;

  case 0xb:  // RBCR1
    // Clear out high byte and re-insert
    BX_NE2K_THIS s.remote_bytes &= 0x00ffu;
    BX_NE2K_THIS s.remote_bytes |= ((value & 0xffu) << 8u);
    break;

  case 0xc:  // RCR
    // Check if the reserved bits are set
    if (value & 0xc0)
      BX_INFO(("RCR write, reserved bits set"));

    // Set all other bit-fields
    BX_NE2K_THIS s.RCR.errors_ok = ((value & 0x01u) == 0x01u);
    BX_NE2K_THIS s.RCR.runts_ok  = ((value & 0x02u) == 0x02u);
    BX_NE2K_THIS s.RCR.broadcast = ((value & 0x04u) == 0x04u);
    BX_NE2K_THIS s.RCR.multicast = ((value & 0x08u) == 0x08u);
    BX_NE2K_THIS s.RCR.promisc   = ((value & 0x10u) == 0x10u);
    BX_NE2K_THIS s.RCR.monitor   = ((value & 0x20u) == 0x20u);

    // Monitor bit is a little suspicious...
    if (value & 0x20)
      BX_INFO(("RCR write, monitor bit set!"));
    break;

  case 0xd:  // TCR
    // Check reserved bits
    if (value & 0xe0)
      BX_ERROR(("TCR write, reserved bits set"));

    // Test loop mode (not supported)
    if (value & 0x06) {
      BX_NE2K_THIS s.TCR.loop_cntl = (value & 0x6) >> 1;
      BX_INFO("TCR write, loop mode %d not supported", BX_NE2K_THIS s.TCR.loop_cntl);
    } else {
      BX_NE2K_THIS s.TCR.loop_cntl = 0;
    }

    // Inhibit-CRC not supported.
    if (value & 0x01)
      BX_PANIC(("TCR write, inhibit-CRC not supported"));

    // Auto-transmit disable very suspicious
    if (value & 0x08)
      BX_PANIC(("TCR write, auto transmit disable not supported"));

    // Allow collision-offset to be set, although not used
    BX_NE2K_THIS s.TCR.coll_prio = ((value & 0x08) == 0x08);
    break;

  case 0xe:  // DCR
    // the loopback mode is not suppported yet
    if (!(value & 0x08)) {
      BX_ERROR(("DCR write, loopback mode selected"));
    }
    // It is questionable to set longaddr and auto_rx, since they
    // aren't supported on the ne2000. Print a warning and continue
    if (value & 0x04)
      BX_INFO(("DCR write - LAS set ???"));
    if (value & 0x10)
      BX_INFO(("DCR write - AR set ???"));

    // Set other values.
    BX_NE2K_THIS s.DCR.wdsize   = ((value & 0x01) == 0x01);
    BX_NE2K_THIS s.DCR.endian   = ((value & 0x02) == 0x02);
    BX_NE2K_THIS s.DCR.longaddr = ((value & 0x04) == 0x04); // illegal ?
    BX_NE2K_THIS s.DCR.loop     = ((value & 0x08) == 0x08);
    BX_NE2K_THIS s.DCR.auto_rx  = ((value & 0x10) == 0x10); // also illegal ?
    BX_NE2K_THIS s.DCR.fifo_size = (value & 0x50) >> 5;
    break;

  case 0xf:  // IMR
    // Check for reserved bit
        if (value & 0x80)
      BX_PANIC(("IMR write, reserved bit set"));

    // Set other values
    BX_NE2K_THIS s.IMR.rx_inte    = ((value & 0x01) == 0x01);
    BX_NE2K_THIS s.IMR.tx_inte    = ((value & 0x02) == 0x02);
    BX_NE2K_THIS s.IMR.rxerr_inte = ((value & 0x04) == 0x04);
    BX_NE2K_THIS s.IMR.txerr_inte = ((value & 0x08) == 0x08);
    BX_NE2K_THIS s.IMR.overw_inte = ((value & 0x10) == 0x10);
    BX_NE2K_THIS s.IMR.cofl_inte  = ((value & 0x20) == 0x20);
    BX_NE2K_THIS s.IMR.rdma_inte  = ((value & 0x40) == 0x40);
        if(BX_NE2K_THIS s.ISR.pkt_tx && BX_NE2K_THIS s.IMR.tx_inte) {
          LOG_MSG("tx irq retrigger");
          PIC_ActivateIRQ((unsigned int)s.base_irq);
        }
    break;
  default:
    BX_PANIC("page 0 write, bad offset %0x", offset);
  }
}


//
// page1_read/page1_write - These routines handle reads/writes to
// the first page of the DS8390 register file
//
Bit32u
bx_ne2k_c::page1_read(Bit32u offset, unsigned int io_len)
{
  BX_DEBUG("page 1 read from port %04x, len=%u", (unsigned) offset,
           (unsigned) io_len);
  if (io_len > 1)
    BX_PANIC("bad length! page 1 read from port %04x, len=%u", (unsigned) offset,
             (unsigned) io_len);

  switch (offset) {
  case 0x1:  // PAR0-5
  case 0x2:
  case 0x3:
  case 0x4:
  case 0x5:
  case 0x6:
    return (BX_NE2K_THIS s.physaddr[offset - 1]);
    break;

  case 0x7:  // CURR
      BX_DEBUG("returning current page: %02x", (BX_NE2K_THIS s.curr_page));
    return (BX_NE2K_THIS s.curr_page);

  case 0x8:  // MAR0-7
  case 0x9:
  case 0xa:
  case 0xb:
  case 0xc:
  case 0xd:
  case 0xe:
  case 0xf:
    return (BX_NE2K_THIS s.mchash[offset - 8]);
    break;

  default:
    BX_PANIC("page 1 r offset %04x out of range", (unsigned) offset);
  }

  return (0);
}

void
bx_ne2k_c::page1_write(Bit32u offset, Bit32u value, unsigned io_len)
{
    (void)io_len;//UNUSED
  BX_DEBUG("page 1 w offset %04x", (unsigned) offset);
  switch (offset) {
  case 0x1:  // PAR0-5
  case 0x2:
  case 0x3:
  case 0x4:
  case 0x5:
  case 0x6:
    BX_NE2K_THIS s.physaddr[offset - 1] = value;
    break;
    
  case 0x7:  // CURR
    BX_NE2K_THIS s.curr_page = value;
    break;

  case 0x8:  // MAR0-7
  case 0x9:
  case 0xa:
  case 0xb:
  case 0xc:
  case 0xd:
  case 0xe:
  case 0xf:
    BX_NE2K_THIS s.mchash[offset - 8] = value;
    break;

  default:
    BX_PANIC("page 1 w offset %04x out of range", (unsigned) offset);
  }  
}


//
// page2_read/page2_write - These routines handle reads/writes to
// the second page of the DS8390 register file
//
Bit32u
bx_ne2k_c::page2_read(Bit32u offset, unsigned int io_len)
{
  BX_DEBUG("page 2 read from port %04x, len=%u", (unsigned) offset, (unsigned) io_len);

  if (io_len > 1)
    BX_PANIC("bad length!  page 2 read from port %04x, len=%u", (unsigned) offset, (unsigned) io_len);

  switch (offset) {
  case 0x1:  // PSTART
    return (BX_NE2K_THIS s.page_start);
    break;

  case 0x2:  // PSTOP
    return (BX_NE2K_THIS s.page_stop);
    break;

  case 0x3:  // Remote Next-packet pointer
    return (BX_NE2K_THIS s.rempkt_ptr);
    break;

  case 0x4:  // TPSR
    return (BX_NE2K_THIS s.tx_page_start);
    break;

  case 0x5:  // Local Next-packet pointer
    return (BX_NE2K_THIS s.localpkt_ptr);
    break;

  case 0x6:  // Address counter (upper)
    return (unsigned int)(BX_NE2K_THIS s.address_cnt >> 8u);
    break;

  case 0x7:  // Address counter (lower)
    return (unsigned int)(BX_NE2K_THIS s.address_cnt & 0xff);
    break;

  case 0x8:  // Reserved
  case 0x9:
  case 0xa:
  case 0xb:
    BX_ERROR("reserved read - page 2, 0x%02x", (unsigned) offset);
    return (0xff);
    break;

  case 0xc:  // RCR
    return
       ((unsigned int)(BX_NE2K_THIS s.RCR.monitor   << 5u) |
            (unsigned int)(BX_NE2K_THIS s.RCR.promisc   << 4u) |
            (unsigned int)(BX_NE2K_THIS s.RCR.multicast << 3u) |
            (unsigned int)(BX_NE2K_THIS s.RCR.broadcast << 2u) |
            (unsigned int)(BX_NE2K_THIS s.RCR.runts_ok  << 1u) |
            (unsigned int)(BX_NE2K_THIS s.RCR.errors_ok));
    break;

  case 0xd:  // TCR
    return
       ((unsigned int)(BX_NE2K_THIS s.TCR.coll_prio         << 4u) |
            (unsigned int)(BX_NE2K_THIS s.TCR.ext_stoptx        << 3u) |
           ((unsigned int)(BX_NE2K_THIS s.TCR.loop_cntl & 0x3u) << 1u) |
            (unsigned int)(BX_NE2K_THIS s.TCR.crc_disable));
    break;

  case 0xe:  // DCR
    return
      (((unsigned int)(BX_NE2K_THIS s.DCR.fifo_size & 0x3) << 5u) |
            (unsigned int)(BX_NE2K_THIS s.DCR.auto_rx          << 4u) |
            (unsigned int)(BX_NE2K_THIS s.DCR.loop             << 3u) |
            (unsigned int)(BX_NE2K_THIS s.DCR.longaddr         << 2u) |
            (unsigned int)(BX_NE2K_THIS s.DCR.endian           << 1u) |
            (unsigned int)(BX_NE2K_THIS s.DCR.wdsize));
    break;

  case 0xf:  // IMR
    return
       ((unsigned int)(BX_NE2K_THIS s.IMR.rdma_inte  << 6u) |
            (unsigned int)(BX_NE2K_THIS s.IMR.cofl_inte  << 5u) |
            (unsigned int)(BX_NE2K_THIS s.IMR.overw_inte << 4u) |
            (unsigned int)(BX_NE2K_THIS s.IMR.txerr_inte << 3u) |
            (unsigned int)(BX_NE2K_THIS s.IMR.rxerr_inte << 2u) |
            (unsigned int)(BX_NE2K_THIS s.IMR.tx_inte    << 1u) |
           (unsigned int) (BX_NE2K_THIS s.IMR.rx_inte));
    break;

  default:
    BX_PANIC("page 2 offset %04x out of range", (unsigned) offset);
  }

  return (0);
}

void
bx_ne2k_c::page2_write(Bit32u offset, Bit32u value, unsigned io_len)
{
    (void)io_len;//UNUSED
  // Maybe all writes here should be BX_PANIC()'d, since they
  // affect internal operation, but let them through for now
  // and print a warning.
  if (offset != 0)
    BX_ERROR(("page 2 write ?"));

  switch (offset) {
  case 0x1:  // CLDA0
    // Clear out low byte and re-insert
    BX_NE2K_THIS s.local_dma &= 0xff00;
    BX_NE2K_THIS s.local_dma |= (value & 0xff);
    break;

  case 0x2:  // CLDA1
    // Clear out high byte and re-insert
    BX_NE2K_THIS s.local_dma &= 0x00ff;
    BX_NE2K_THIS s.local_dma |= ((value & 0xff) << 8u);
    break;

  case 0x3:  // Remote Next-pkt pointer
    BX_NE2K_THIS s.rempkt_ptr = value;
    break;

  case 0x4:
    BX_PANIC(("page 2 write to reserved offset 4"));
    break;

  case 0x5:  // Local Next-packet pointer
    BX_NE2K_THIS s.localpkt_ptr = value;
    break;

  case 0x6:  // Address counter (upper)
    // Clear out high byte and re-insert
    BX_NE2K_THIS s.address_cnt &= 0x00ff;
    BX_NE2K_THIS s.address_cnt |= ((value & 0xff) << 8);
    break;

  case 0x7:  // Address counter (lower)
    // Clear out low byte and re-insert
    BX_NE2K_THIS s.address_cnt &= 0xff00;
    BX_NE2K_THIS s.address_cnt |= (value & 0xff);
    break;

  case 0x8:
  case 0x9:
  case 0xa:
  case 0xb:
  case 0xc:
  case 0xd:
  case 0xe:
  case 0xf:
    BX_PANIC("page 2 write to reserved offset %0x", offset);
    break;
   
  default:
    BX_PANIC("page 2 write, illegal offset %0x", offset);
    break;
  }
}
  
//
// page3_read/page3_write - writes to this page are illegal
//
Bit32u
bx_ne2k_c::page3_read(Bit32u offset, unsigned int io_len)
{
    (void)offset;//UNUSED
    (void)io_len;//UNUSED
  BX_PANIC(("page 3 read attempted"));
  return (0);
}

void
bx_ne2k_c::page3_write(Bit32u offset, Bit32u value, unsigned io_len)
{
    (void)value;//UNUSED
    (void)offset;//UNUSED
    (void)io_len;//UNUSED
  BX_PANIC(("page 3 write attempted"));
}

//
// tx_timer_handler/tx_timer
//
void
bx_ne2k_c::tx_timer_handler(void *this_ptr)
{
  bx_ne2k_c *class_ptr = (bx_ne2k_c *) this_ptr;

  class_ptr->tx_timer();
}

void
bx_ne2k_c::tx_timer(void)
{
  BX_DEBUG(("tx_timer"));
  BX_NE2K_THIS s.TSR.tx_ok = 1;
  // Generate an interrupt if not masked and not one in progress
  if (BX_NE2K_THIS s.IMR.tx_inte && !BX_NE2K_THIS s.ISR.pkt_tx) {
                //LOG_MSG("tx complete interrupt");
          PIC_ActivateIRQ((unsigned int)s.base_irq);
    //DEV_pic_raise_irq(BX_NE2K_THIS s.base_irq);
  } //else        LOG_MSG("no tx complete interrupt");
  BX_NE2K_THIS s.ISR.pkt_tx = 1;
  BX_NE2K_THIS s.tx_timer_active = 0;
}


//
// read_handler/read - i/o 'catcher' function called from BOCHS
// mainline when the CPU attempts a read in the i/o space registered
// by this ne2000 instance
//
Bit32u bx_ne2k_c::read_handler(void *this_ptr, Bit32u address, unsigned io_len)
{
#if !BX_USE_NE2K_SMF
  bx_ne2k_c *class_ptr = (bx_ne2k_c *) this_ptr;

  return( class_ptr->read(address, io_len) );
}

Bit32u bx_ne2k_c::read(Bit32u address, unsigned io_len)
{
#else
  UNUSED(this_ptr);
#endif  // !BX_USE_NE2K_SMF
  BX_DEBUG("read addr %x, len %d", address, io_len);
  Bit32u retval = 0;
  unsigned int offset = (unsigned int)address - (unsigned int)(BX_NE2K_THIS s.base_address);

  if (offset >= 0x10) {
    retval = asic_read(offset - 0x10, io_len);
  } else if (offset == 0x00) {
    retval = read_cr();
  } else {
    switch (BX_NE2K_THIS s.CR.pgsel) {
    case 0x00:
      retval = page0_read(offset, io_len);
      break;

    case 0x01:
      retval = page1_read(offset, io_len);
      break;

    case 0x02:
      retval = page2_read(offset, io_len);
      break;

    case 0x03:
      retval = page3_read(offset, io_len);
      break;

    default:
      BX_PANIC("ne2K: unknown value of pgsel in read - %d",
               BX_NE2K_THIS s.CR.pgsel);
    }
  }

  return (retval);
}

//
// write_handler/write - i/o 'catcher' function called from BOCHS
// mainline when the CPU attempts a write in the i/o space registered
// by this ne2000 instance
//
void
bx_ne2k_c::write_handler(void *this_ptr, Bit32u address, Bit32u value, 
                         unsigned io_len)
{
#if !BX_USE_NE2K_SMF
  bx_ne2k_c *class_ptr = (bx_ne2k_c *) this_ptr;
  
  class_ptr->write(address, value, io_len);
}

void
bx_ne2k_c::write(Bit32u address, Bit32u value, unsigned io_len)
{
#else
  UNUSED(this_ptr);
#endif  // !BX_USE_NE2K_SMF
  BX_DEBUG("write with length %d", io_len);
  unsigned int offset = (unsigned int)address - (unsigned int)(BX_NE2K_THIS s.base_address);

  //
  // The high 16 bytes of i/o space are for the ne2000 asic -
  //  the low 16 bytes are for the DS8390, with the current
  //  page being selected by the PS0,PS1 registers in the
  //  command register
  //
  if (offset >= 0x10) {
    asic_write(offset - 0x10, value, io_len);
        } else if (offset == 0x00) {
    write_cr(value);
  } else {
    switch (BX_NE2K_THIS s.CR.pgsel) {
    case 0x00:
      page0_write(offset, value, io_len);
      break;

    case 0x01:
      page1_write(offset, value, io_len);
      break;

    case 0x02:
      page2_write(offset, value, io_len);
      break;

    case 0x03:
      page3_write(offset, value, io_len);
      break;

    default:
      BX_PANIC("ne2K: unknown value of pgsel in write - %d",
               BX_NE2K_THIS s.CR.pgsel);
    }
  }
}


/*
 * mcast_index() - return the 6-bit index into the multicast
 * table. Stolen unashamedly from FreeBSD's if_ed.c
 */
unsigned
bx_ne2k_c::mcast_index(const void *dst)
{
#define POLYNOMIAL 0x04c11db6
  unsigned long crc = 0xffffffffL;
  int carry, i, j;
  unsigned char b;
  unsigned char *ep = (unsigned char *) dst;

  for (i = 6; --i >= 0;) {
      b = *ep++;
      for (j = 8; --j >= 0;) {
          carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
          crc <<= 1;
          b >>= 1;
          if (carry)
              crc = ((crc ^ POLYNOMIAL) | (unsigned int)carry);
      }
  }

  return (uint32_t)((crc & 0xfffffffful) >> 26ul); /* WARNING: Caller directly uses our 6-bit return as index. If not truncated, will cause a segfault */
#undef POLYNOMIAL
}

/*
 * Callback from the eth system driver when a frame has arrived
 */
/*
void
bx_ne2k_c::rx_handler(void *arg, const void *buf, unsigned len)
{
    // BX_DEBUG(("rx_handler with length %d", len));
  bx_ne2k_c *class_ptr = (bx_ne2k_c *) arg;
  if(
  class_ptr->rx_frame(buf, len);
}
*/
/*
 * rx_frame() - called by the platform-specific code when an
 * ethernet frame has been received. The destination address
 * is tested to see if it should be accepted, and if the
 * rx ring has enough room, it is copied into it and
 * the receive process is updated
 */
void
bx_ne2k_c::rx_frame(const void *buf, unsigned io_len)
{
  int pages;
  int avail;
  unsigned idx;
//  int wrapped;
  int nextpage;
  unsigned char pkthdr[4];
  unsigned char *pktbuf = (unsigned char *) buf;
  unsigned char *startptr;
  static unsigned char bcast_addr[6] = {0xff,0xff,0xff,0xff,0xff,0xff};

  if(io_len != 60) {
        BX_DEBUG("rx_frame with length %d", io_len);
  }

        //LOG_MSG("stop=%d, pagestart=%x, dcr_loop=%x, tcr_loopcntl=%x",
        //      BX_NE2K_THIS s.CR.stop, BX_NE2K_THIS s.page_start,
        //      BX_NE2K_THIS s.DCR.loop, BX_NE2K_THIS s.TCR.loop_cntl);
  if ((BX_NE2K_THIS s.CR.stop != 0) ||
      (BX_NE2K_THIS s.page_start == 0) /*||
      ((BX_NE2K_THIS s.DCR.loop == 0) &&
       (BX_NE2K_THIS s.TCR.loop_cntl != 0))*/) {
    return;
  }

  // Add the pkt header + CRC to the length, and work
  // out how many 256-byte pages the frame would occupy
  pages = (int)((io_len + 4u + 4u + 255u)/256u);

  if (BX_NE2K_THIS s.curr_page < BX_NE2K_THIS s.bound_ptr) {
    avail = BX_NE2K_THIS s.bound_ptr - BX_NE2K_THIS s.curr_page;    
  } else {
    avail = (BX_NE2K_THIS s.page_stop - BX_NE2K_THIS s.page_start) -
      (BX_NE2K_THIS s.curr_page - BX_NE2K_THIS s.bound_ptr);
//    wrapped = 1;
  }

  // Avoid getting into a buffer overflow condition by not attempting
  // to do partial receives. The emulation to handle this condition
  // seems particularly painful.
  if ((avail < pages) 
#if BX_NE2K_NEVER_FULL_RING
      || (avail == pages)
#endif
      ) {
        BX_DEBUG("no space");
    return;
  }

  if ((io_len < 40/*60*/) && !BX_NE2K_THIS s.RCR.runts_ok) {
    BX_DEBUG("rejected small packet, length %d", io_len);
    return;
  }
  // some computers don't care...
  if (io_len < 60) io_len=60;

  // Do address filtering if not in promiscuous mode
  if (! BX_NE2K_THIS s.RCR.promisc) {
    if (!memcmp(buf, bcast_addr, 6)) {
      if (!BX_NE2K_THIS s.RCR.broadcast) {
        return;
      }
    } else if (pktbuf[0] & 0x01) {
        if (! BX_NE2K_THIS s.RCR.multicast) {
            return;
        }
      idx = mcast_index(buf);
      if (!(BX_NE2K_THIS s.mchash[idx >> 3] & (1 << (idx & 0x7)))) {
        return;
      }
    } else if (0 != memcmp(buf, BX_NE2K_THIS s.physaddr, 6)) {
      return;
    }
  } else {
      BX_DEBUG(("rx_frame promiscuous receive"));
  }

    BX_INFO("rx_frame %d to %x:%x:%x:%x:%x:%x from %x:%x:%x:%x:%x:%x",
           io_len,
           pktbuf[0], pktbuf[1], pktbuf[2], pktbuf[3], pktbuf[4], pktbuf[5],
           pktbuf[6], pktbuf[7], pktbuf[8], pktbuf[9], pktbuf[10], pktbuf[11]);

  nextpage = BX_NE2K_THIS s.curr_page + pages;
  if (nextpage >= BX_NE2K_THIS s.page_stop) {
    nextpage -= BX_NE2K_THIS s.page_stop - BX_NE2K_THIS s.page_start;
  }

  // Setup packet header
  pkthdr[0] = 0;        // rx status - old behavior
  pkthdr[0] = 1;        // Probably better to set it all the time
                        // rather than set it to 0, which is clearly wrong.
  if (pktbuf[0] & 0x01) {
    pkthdr[0] |= 0x20;  // rx status += multicast packet
  }
  pkthdr[1] = nextpage; // ptr to next packet
  pkthdr[2] = (io_len + 4) & 0xff;      // length-low
  pkthdr[3] = (io_len + 4) >> 8;        // length-hi

  // copy into buffer, update curpage, and signal interrupt if config'd
  startptr = & BX_NE2K_THIS s.mem[BX_NE2K_THIS s.curr_page * 256 -
                               BX_NE2K_MEMSTART];
  if ((nextpage > BX_NE2K_THIS s.curr_page) ||
      ((BX_NE2K_THIS s.curr_page + pages) == BX_NE2K_THIS s.page_stop)) {
    memcpy(startptr, pkthdr, 4);
    memcpy(startptr + 4, buf, io_len);
    BX_NE2K_THIS s.curr_page = nextpage;
  } else {
    unsigned int endbytes = (unsigned int)(BX_NE2K_THIS s.page_stop - BX_NE2K_THIS s.curr_page) 
      * 256u;
    memcpy(startptr, pkthdr, 4);
    memcpy(startptr + 4, buf, (size_t)(endbytes - 4u));
    startptr = & BX_NE2K_THIS s.mem[BX_NE2K_THIS s.page_start * 256u -
                                 BX_NE2K_MEMSTART];
    memcpy(startptr, (void *)(pktbuf + endbytes - 4u),
           (size_t)(io_len - endbytes + 8u));
    BX_NE2K_THIS s.curr_page = nextpage;
  }
  
  BX_NE2K_THIS s.RSR.rx_ok = 1;
  if (pktbuf[0] & 0x80) {
    BX_NE2K_THIS s.RSR.rx_mbit = 1;
  }

  BX_NE2K_THIS s.ISR.pkt_rx = 1;

  if (BX_NE2K_THIS s.IMR.rx_inte) {
        //LOG_MSG("packet rx interrupt");
          PIC_ActivateIRQ((unsigned int)s.base_irq);
    //DEV_pic_raise_irq(BX_NE2K_THIS s.base_irq);
  } //else LOG_MSG("no packet rx interrupt");

}

//Bit8u macaddr[6] = { 0xAC, 0xDE, 0x48, 0x8E, 0x89, 0x19 };

Bitu dosbox_read(Bitu port, Bitu len) {
        Bitu retval = theNE2kDevice->read((Bit32u)port,(unsigned int)len);
        //LOG_MSG("ne2k rd port %x val %4x len %d page %d, CS:IP %8x:%8x",
        //      port, retval, len, theNE2kDevice->s.CR.pgsel,SegValue(cs),reg_eip);
        return retval;
}
void dosbox_write(Bitu port, Bitu val, Bitu len) {
        //LOG_MSG("ne2k wr port %x val %4x len %d page %d, CS:IP %8x:%8x",
        //      port, val, len,theNE2kDevice->s.CR.pgsel,SegValue(cs),reg_eip);
        theNE2kDevice->write((Bit32u)port, (Bit32u)val, (unsigned int)len);
}

void bx_ne2k_c::init()
{
  //BX_DEBUG(("Init $Id: ne2k.cc,v 1.56.2.1 2004/02/02 22:37:22 cbothamy Exp $"));

  // Read in values from config file
  //BX_NE2K_THIS s.base_address = 0x300;
  //BX_NE2K_THIS s.base_irq     = 3;
  /*
  if (BX_NE2K_THIS s.tx_timer_index == BX_NULL_TIMER_HANDLE) {
    BX_NE2K_THIS s.tx_timer_index =
      bx_pc_system.register_timer(this, tx_timer_handler, 0,
                                  0,0, "ne2k"); // one-shot, inactive
  }*/
  // Register the IRQ and i/o port addresses
  //DEV_register_irq(BX_NE2K_THIS s.base_irq, "NE2000 ethernet NIC");

   //DEV_register_ioread_handler(this, read_handler, addr, "ne2000 NIC", 3);
   //DEV_register_iowrite_handler(this, write_handler, addr, "ne2000 NIC", 3);


  BX_INFO("port 0x%x/32 irq %d mac %02x:%02x:%02x:%02x:%02x:%02x",
           (unsigned int)(BX_NE2K_THIS s.base_address),
           (int)(BX_NE2K_THIS s.base_irq),
           BX_NE2K_THIS s.physaddr[0],
           BX_NE2K_THIS s.physaddr[1],
           BX_NE2K_THIS s.physaddr[2],
           BX_NE2K_THIS s.physaddr[3],
           BX_NE2K_THIS s.physaddr[4],
           BX_NE2K_THIS s.physaddr[5]);

  // Initialise the mac address area by doubling the physical address
  BX_NE2K_THIS s.macaddr[0]  = BX_NE2K_THIS s.physaddr[0];
  BX_NE2K_THIS s.macaddr[1]  = BX_NE2K_THIS s.physaddr[0];
  BX_NE2K_THIS s.macaddr[2]  = BX_NE2K_THIS s.physaddr[1];
  BX_NE2K_THIS s.macaddr[3]  = BX_NE2K_THIS s.physaddr[1];
  BX_NE2K_THIS s.macaddr[4]  = BX_NE2K_THIS s.physaddr[2];
  BX_NE2K_THIS s.macaddr[5]  = BX_NE2K_THIS s.physaddr[2];
  BX_NE2K_THIS s.macaddr[6]  = BX_NE2K_THIS s.physaddr[3];
  BX_NE2K_THIS s.macaddr[7]  = BX_NE2K_THIS s.physaddr[3];
  BX_NE2K_THIS s.macaddr[8]  = BX_NE2K_THIS s.physaddr[4];
  BX_NE2K_THIS s.macaddr[9]  = BX_NE2K_THIS s.physaddr[4];
  BX_NE2K_THIS s.macaddr[10] = BX_NE2K_THIS s.physaddr[5];
  BX_NE2K_THIS s.macaddr[11] = BX_NE2K_THIS s.physaddr[5];
    
  // ne2k signature
  for (Bitu i = 12; i < 32; i++) 
    BX_NE2K_THIS s.macaddr[i] = 0x57;
    
  // Bring the register state into power-up state
  reset(BX_RESET_HARDWARE);
}

static void NE2000_TX_Event(Bitu val) {
    (void)val;//UNUSED
        theNE2kDevice->tx_timer();
}

static void NE2000_Poller(void) {
        int res;
        struct pcap_pkthdr *header;
        u_char *pkt_data;
//#if 0
        while((res = pcap_next_ex( adhandle, &header, (const u_char **)&pkt_data)) > 0) {
                //LOG_MSG("NE2000: Received %d bytes", header->len);
                
                // don't receive in loopback modes
                if((theNE2kDevice->s.DCR.loop == 0) || (theNE2kDevice->s.TCR.loop_cntl != 0))
                        return;
                theNE2kDevice->rx_frame(pkt_data, header->len);
        }
//#endif
}
#ifdef WIN32
#include <windows.h>
#endif

class NE2K: public Module_base {
private:
        // Data
        IO_ReadHandleObject ReadHandler8[0x20];
        IO_WriteHandleObject WriteHandler8[0x20];
        IO_ReadHandleObject ReadHandler16[0x10];
        IO_WriteHandleObject WriteHandler16[0x10];

public:
        bool load_success;
        NE2K(Section* configuration):Module_base(configuration) {
                Section_prop * section=static_cast<Section_prop *>(configuration);

                load_success = true;
                // enabled?

                if(!section->Get_bool("ne2000")) {
                        load_success = false;
                        return;
                }

#ifdef WIN32
/*              
                int (*PacketSendPacket)(pcap_t *, const u_char *, int);
                void (*PacketClose)(pcap_t *);
                void (*PacketFreealldevs)(pcap_if_t *);
                pcap_t* (*PacketOpen)(char const *,int,int,int,struct pcap_rmtauth *,char *);
                int (*PacketNextEx)(pcap_t *, struct pcap_pkthdr **, const u_char **);
                int (*PacketFindALlDevsEx)(char *, struct pcap_rmtauth *, pcap_if_t **, char *);
*/
                // init the library
                HINSTANCE pcapinst;
                pcapinst = LoadLibrary("WPCAP.DLL");
                if(pcapinst==NULL) {
                        LOG_MSG("WinPcap has to be installed for the NE2000 to work.");
                        load_success = false;
                        return;
                }
                FARPROC psp;
                
                psp = GetProcAddress(pcapinst,"pcap_sendpacket");
                if(!PacketSendPacket) PacketSendPacket =
                        (int (__cdecl *)(pcap_t *,const u_char *,int))psp;
                
                psp = GetProcAddress(pcapinst,"pcap_close");
                if(!PacketClose) PacketClose =
                        (void (__cdecl *)(pcap_t *)) psp;
                
                psp = GetProcAddress(pcapinst,"pcap_freealldevs");
                if(!PacketFreealldevs) PacketFreealldevs =
                        (void (__cdecl *)(pcap_if_t *)) psp;

                psp = GetProcAddress(pcapinst,"pcap_open");
                if(!PacketOpen) PacketOpen =
                        (pcap_t* (__cdecl *)(char const *,int,int,int,struct pcap_rmtauth *,char *)) psp;

                psp = GetProcAddress(pcapinst,"pcap_next_ex");
                if(!PacketNextEx) PacketNextEx = 
                        (int (__cdecl *)(pcap_t *, struct pcap_pkthdr **, const u_char **)) psp;

                psp = GetProcAddress(pcapinst,"pcap_findalldevs_ex");
                if(!PacketFindALlDevsEx) PacketFindALlDevsEx =
                        (int (__cdecl *)(char *, struct pcap_rmtauth *, pcap_if_t **, char *)) psp;

                if(PacketFindALlDevsEx==0 || PacketNextEx==0 || PacketOpen==0 || 
                        PacketFreealldevs==0 || PacketClose==0 || PacketSendPacket==0) {
                        LOG_MSG("Wrong WinPcap version or something");
                        load_success = false;
                        return;
                }

#endif

                // get irq and base
                Bitu irq = (Bitu)section->Get_int("nicirq");
                if(!(irq==3 || irq==4  || irq==5  || irq==6 ||irq==7 ||
                        irq==9 || irq==10 || irq==11 || irq==12 ||irq==14 ||irq==15)) {
                        irq=3;
                }
                Bitu base = (Bitu)section->Get_hex("nicbase");
                if(!(base==0x260||base==0x280||base==0x300||base==0x320||base==0x340||base==0x380)) {
                        base=0x300;
                }

        LOG_MSG("NE2000: Base=0x%x irq=%u",(unsigned int)base,(unsigned int)irq);

                // mac address
                const char* macstring=section->Get_string("macaddr");
                unsigned int macint[6];
                Bit8u mac[6];
                if(sscanf(macstring,"%02x:%02x:%02x:%02x:%02x:%02x",
                        &macint[0],&macint[1],&macint[2],&macint[3],&macint[4],&macint[5]) != 6) {
                        mac[0]=0xac;mac[1]=0xde;mac[2]=0x48;
                        mac[3]=0x88;mac[4]=0xbb;mac[5]=0xaa;
                } else {
                        mac[0]=macint[0]; mac[1]=macint[1];
                        mac[2]=macint[2]; mac[3]=macint[3];
                        mac[4]=macint[4]; mac[5]=macint[5];
                }

                // find out which pcap device to use
                const char* realnicstring=section->Get_string("realnic");
                pcap_if_t *alldevs;
                pcap_if_t *currentdev = NULL;
                char errbuf[PCAP_ERRBUF_SIZE];
                unsigned int userdev;
#ifdef WIN32
                if (pcap_findalldevs_ex(PCAP_SRC_IF_STRING, NULL, &alldevs, errbuf) == -1)
#else
                if (pcap_findalldevs(&alldevs, errbuf) == -1)
#endif
                {
                        LOG_MSG("Cannot enumerate network interfaces: %s\n", errbuf);
                        load_success = false;
                        return;
                }
                if (!strcasecmp(realnicstring,"list")) {
                        // print list and quit
                        Bitu i = 0;
                        LOG_MSG("\nNetwork Interface List \n-----------------------------------");
                        for(currentdev=alldevs; currentdev!=NULL; currentdev=currentdev->next) {
                                const char* desc = "no description"; 
                                if(currentdev->description) desc=currentdev->description;
                                i++;
                                LOG_MSG("%2d. %s\n    (%s)\n",(int)i,currentdev->name,desc);
                        }
                        pcap_freealldevs(alldevs);
                        load_success = false;
                        return;
                } else if(1==sscanf(realnicstring,"%u",&userdev)) {
                        // user passed us a number
                        Bitu i = 0;
                        currentdev=alldevs;
                        while(currentdev!=NULL) {
                                i++;
                                if(i==userdev) break;
                                else currentdev=currentdev->next;
                        }
                } else {
                        // user might have passed a piece of name
                        for(currentdev=alldevs; currentdev!=NULL; currentdev=currentdev->next) {
                                if(strstr(currentdev->name,realnicstring)) {
                                        break;
                                }else if(currentdev->description!=NULL &&
                                        strstr(currentdev->description,realnicstring)) {
                                        break;
                                }
                        }
                }

                if(currentdev==NULL) {
                        LOG_MSG("Unable to find network interface - check realnic parameter\n");
                        load_success = false;
                        pcap_freealldevs(alldevs);
                        return;
                }
                // print out which interface we are going to use
        const char* desc = "no description"; 
                if(currentdev->description) desc=currentdev->description;
                LOG_MSG("Using Network interface:\n%s\n(%s)\n",currentdev->name,desc);
                
                // attempt to open it
#ifdef WIN32
                if ( (adhandle= pcap_open(
                        currentdev->name, // name of the device
            65536,            // portion of the packet to capture
                              // 65536 = whole packet 
            PCAP_OPENFLAG_PROMISCUOUS,    // promiscuous mode
            -1,             // read timeout
            NULL,             // authentication on the remote machine
            errbuf            // error buffer
            ) ) == NULL)
#else
                /*pcap_t *pcap_open_live(const char *device, int snaplen,
               int promisc, int to_ms, char *errbuf)*/
                if ( (adhandle= pcap_open_live(
                        currentdev->name, // name of the device
            65536,            // portion of the packet to capture
                              // 65536 = whole packet 
            true,    // promiscuous mode
            -1,             // read timeout
            errbuf            // error buffer
            ) ) == NULL)

#endif        
        {
                                LOG_MSG("\nUnable to open the interface: %s.", errbuf);
                pcap_freealldevs(alldevs);
                        load_success = false;
                        return;
                }
                pcap_freealldevs(alldevs);
#ifndef WIN32
                pcap_setnonblock(adhandle,1,errbuf);
#endif
                // create the bochs NIC class
                theNE2kDevice = new bx_ne2k_c ();
                memcpy(theNE2kDevice->s.physaddr, mac, 6);

                theNE2kDevice->s.base_address=(Bit32u)base;
                theNE2kDevice->s.base_irq=(int)irq;

                theNE2kDevice->init();

                // install I/O-handlers and timer
                for(Bitu i = 0; i < 0x20; i++) {
                        ReadHandler8[i].Install((i+theNE2kDevice->s.base_address),
                                dosbox_read,IO_MB|IO_MW);
                        WriteHandler8[i].Install((i+theNE2kDevice->s.base_address),
                                dosbox_write,IO_MB|IO_MW);
                }
                TIMER_AddTickHandler(NE2000_Poller);
        }       
        
        ~NE2K() {
                if(adhandle) pcap_close(adhandle);
                adhandle=0;
                if(theNE2kDevice != 0) delete theNE2kDevice;
                theNE2kDevice=0;
                TIMER_DelTickHandler(NE2000_Poller);
                PIC_RemoveEvents(NE2000_TX_Event);
        }       
};

static NE2K* test = NULL;

void NE2K_ShutDown(Section* sec) {
    (void)sec;//UNUSED
        if (test) {
        delete test;    
        test = NULL;
    }
}

void NE2K_OnReset(Section* sec) {
    (void)sec;//UNUSED
        if (test == NULL && !IS_PC98_ARCH) {
                LOG(LOG_MISC,LOG_DEBUG)("Allocating NE2000 emulation");
                test = new NE2K(control->GetSection("ne2000"));

                if (!test->load_success) {
                        LOG(LOG_MISC,LOG_DEBUG)("Sorry, NE2000 allocation failed to load");
                        delete test;
                        test = NULL;
                }
        }
}

void NE2K_Init() {
        LOG(LOG_MISC,LOG_DEBUG)("Initializing NE2000 network card emulation");

        AddExitFunction(AddExitFunctionFuncPair(NE2K_ShutDown),true);
        AddVMEventFunction(VM_EVENT_RESET,AddVMEventFunctionFuncPair(NE2K_OnReset));
}

#endif // C_NE2000