Bochs/bochs/cpu/io.cc

/////////////////////////////////////////////////////////////////////////
// $Id: io.cc,v 1.30 2006-03-26 19:39:37 sshwarts Exp $
/////////////////////////////////////////////////////////////////////////
//
//  Copyright (C) 2001  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 Lesser General Public
//  License along with this library; if not, write to the Free Software
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA


#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#include "cpu.h"
#define LOG_THIS BX_CPU_THIS_PTR

#include "iodev/iodev.h"


#if BX_SUPPORT_X86_64==0
// Make life easier for merging cpu64 and cpu32 code.
#define RDI EDI
#define RSI ESI
#define RAX EAX
#endif


void BX_CPU_C::INSB_YbDX(bxInstruction_c *i)
{
  Bit8u value8=0;

  if (BX_CPU_THIS_PTR cr0.pe && (BX_CPU_THIS_PTR get_VM () || (CPL>BX_CPU_THIS_PTR get_IOPL ()))) {
    if ( !BX_CPU_THIS_PTR allow_io(DX, 1) ) {
      exception(BX_GP_EXCEPTION, 0, 0);
    }
  }

#if BX_SUPPORT_X86_64
  if (i->as64L()) {
    // Write a zero to memory, to trigger any segment or page
    // faults before reading from IO port.
    write_virtual_byte(BX_SEG_REG_ES, RDI, &value8);

    value8 = BX_INP(DX, 1);

    /* no seg override possible */
    write_virtual_byte(BX_SEG_REG_ES, RDI, &value8);

    if (BX_CPU_THIS_PTR get_DF ())
      RDI--;
    else
      RDI++;
  }
  else
#endif
   if (i->as32L()) {
    // Write a zero to memory, to trigger any segment or page
    // faults before reading from IO port.
    write_virtual_byte(BX_SEG_REG_ES, EDI, &value8);

    value8 = BX_INP(DX, 1);

    /* no seg override possible */
    write_virtual_byte(BX_SEG_REG_ES, EDI, &value8);

    if (BX_CPU_THIS_PTR get_DF ()) {
      RDI = EDI - 1;
    }
    else {
      RDI = EDI + 1;
    }
  }
  else {
    // Write a zero to memory, to trigger any segment or page
    // faults before reading from IO port.
    write_virtual_byte(BX_SEG_REG_ES, DI, &value8);

    value8 = BX_INP(DX, 1);

    /* no seg override possible */
    write_virtual_byte(BX_SEG_REG_ES, DI, &value8);

    if (BX_CPU_THIS_PTR get_DF ())
      DI--;
    else
      DI++;
  }
}

void BX_CPU_C::INSW_YvDX(bxInstruction_c *i)
  // input word/doubleword from port to string
{
  bx_address edi;
  unsigned int incr;

#if BX_SUPPORT_X86_64
  if (i->as64L())  // This was coded as   if (i->as_64) ???
    edi = RDI;
  else
#endif
   if (i->as32L())
    edi = EDI;
  else
    edi = DI;

  if (i->os32L()) {
    Bit32u value32=0;

    if (BX_CPU_THIS_PTR cr0.pe && (BX_CPU_THIS_PTR get_VM () || (CPL>BX_CPU_THIS_PTR get_IOPL ()))) {
      if ( !BX_CPU_THIS_PTR allow_io(DX, 4) ) {
        exception(BX_GP_EXCEPTION, 0, 0);
      }
    }

    // Write a zero to memory, to trigger any segment or page
    // faults before reading from IO port.
    write_virtual_dword(BX_SEG_REG_ES, edi, &value32);

    value32 = BX_INP(DX, 4);

    /* no seg override allowed */
    write_virtual_dword(BX_SEG_REG_ES, edi, &value32);
    incr = 4;
  }
  else {
    Bit16u value16=0;

    if (BX_CPU_THIS_PTR cr0.pe && (BX_CPU_THIS_PTR get_VM () || (CPL>BX_CPU_THIS_PTR get_IOPL ()))) {
      if ( !BX_CPU_THIS_PTR allow_io(DX, 2) )
        exception(BX_GP_EXCEPTION, 0, 0);
      }

#if BX_SupportRepeatSpeedups
#if (BX_DEBUGGER == 0)
#if (defined(__i386__) && __i386__)
    /* If conditions are right, we can transfer IO to physical memory
     * in a batch, rather than one instruction at a time.
     */
    if (i->repUsedL() && !BX_CPU_THIS_PTR async_event) {
      Bit32u wordCount;

#if BX_SUPPORT_X86_64
      if (i->as64L())
        wordCount = RCX; // Truncated to 32bits. (we're only doing 1 page)
      else
#endif
      if (i->as32L())
        wordCount = ECX;
      else
        wordCount = CX;

      if (wordCount) {
        bx_address laddrDst;
        Bit32u paddrDst, wordsFitDst;
        Bit8u *hostAddrDst;
        bx_segment_reg_t *dstSegPtr;
        int pointerDelta;

        dstSegPtr = &BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES];

        // Do segment checks for the 1st word.  We do not want to
        // trip an exception beyond this, because the address would
        // be incorrect.  After we know how many bytes we will directly
        // transfer, we can do the full segment limit check ourselves
        // without generating an exception.
        write_virtual_checks(dstSegPtr, edi, 2);
        laddrDst = BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_ES) + edi;
        if (BX_CPU_THIS_PTR cr0.pg)
          paddrDst = dtranslate_linear(laddrDst, CPL==3, BX_WRITE);
        else
          paddrDst = laddrDst;
        // If we want to write directly into the physical memory array,
        // we need the A20 address.
        paddrDst = A20ADDR(paddrDst);

        hostAddrDst = BX_CPU_THIS_PTR mem->getHostMemAddr(BX_CPU_THIS,
            paddrDst, BX_WRITE, DATA_ACCESS);

        // Check that native host access was not vetoed for that page, and
        // that the address is word aligned.
        if ( hostAddrDst && ! (paddrDst & 1) ) {
          // See how many words can fit in the rest of this page.
          if (BX_CPU_THIS_PTR get_DF ()) {
            // Counting downward.
            // Note: 1st word must not cross page boundary.
            if ( (paddrDst & 0xfff) > 0xffe )
              goto noAcceleration;
            wordsFitDst = (2 + (paddrDst & 0xfff)) >> 1;
            pointerDelta = -2;
          }
          else {
            // Counting upward.
            wordsFitDst = (0x1000 - (paddrDst & 0xfff)) >> 1;
            pointerDelta =  2;
          }

          // Restrict word count to the number that will fit in this page.
          if (wordCount > wordsFitDst)
            wordCount = wordsFitDst;

          // If after all the restrictions, there is anything left to do...
          if (wordCount) {
            unsigned j;
            Bit32u dstSegLimit;

            dstSegLimit = dstSegPtr->cache.u.segment.limit_scaled;
            // For 16-bit addressing mode, clamp the segment limits to 16bits
            // so we don't have to worry about computations using si/di
            // rolling over 16-bit boundaries.
            if (!i->as32L()) {
              if (dstSegLimit > 0xffff)
                dstSegLimit = 0xffff;
              }

            // Before we copy memory, we need to make sure that the segments
            // allow the accesses up to the given source and dest offset.  If
            // the cache.valid bits have SegAccessWOK and ROK, we know that
            // the cache is valid for those operations, and that the segments
            // are non-expand down (thus we can make a simple limit check).
            if ( !(dstSegPtr->cache.valid & SegAccessWOK) ) {
              goto noAcceleration;
            }
            if (BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64) {
              // Now make sure transfer will fit within the constraints of the
              // segment boundaries, 0..limit for non expand-down.  We know
              // wordCount >= 1 here.
              if (BX_CPU_THIS_PTR get_DF ()) {
                // Counting downward.
                Bit32u minOffset = (wordCount-1) << 1;
                if ( edi < minOffset )
                  goto noAcceleration;
              }
              else {
                // Counting upward.
                Bit32u dstMaxOffset = (dstSegLimit - (wordCount<<1)) + 1;
                if ( edi > dstMaxOffset )
                  goto noAcceleration;
              }
            }

            for (j=0; j<wordCount; ) {
              Bit16u temp16;
              bx_devices.bulkIOQuantumsTransferred = 0;
              if ( BX_CPU_THIS_PTR get_DF ()==0 ) { // Only do accel for DF=0
                bx_devices.bulkIOHostAddr = hostAddrDst;
                bx_devices.bulkIOQuantumsRequested = (wordCount - j);
              }
              else
                bx_devices.bulkIOQuantumsRequested = 0;
              temp16 = BX_INP(DX, 2);
              if ( bx_devices.bulkIOQuantumsTransferred ) {
                hostAddrDst =  bx_devices.bulkIOHostAddr;
                j += bx_devices.bulkIOQuantumsTransferred;
              }
              else {
                * (Bit16u *) hostAddrDst = temp16;
                hostAddrDst += pointerDelta;
                j++;
              }
              // Terminate early if there was an event.
              if ( BX_CPU_THIS_PTR async_event )
                break;
            }
            // Reset for next non-bulk IO.
            bx_devices.bulkIOQuantumsRequested = 0;
            wordCount = j;
            // Decrement eCX.  Note, the main loop will decrement 1 also, so
            // decrement by one less than expected, like the case above.
            BX_TICKN(j-1); // Main cpu loop also decrements one more.
#if BX_SUPPORT_X86_64
            if (i->as64L())
              RCX -= (wordCount-1);
            else
#endif
            if (i->as32L())
              ECX -= (wordCount-1);
            else
              CX  -= (wordCount-1);
            incr = wordCount << 1; // count * 2.
            goto doIncr;
          }
        }
      }
    }

noAcceleration:

#endif  // __i386__
#endif  // (BX_DEBUGGER == 0)
#endif  // #if BX_SupportRepeatSpeedups

    // Write a zero to memory, to trigger any segment or page
    // faults before reading from IO port.
    write_virtual_word(BX_SEG_REG_ES, edi, &value16);

    value16 = BX_INP(DX, 2);

    /* no seg override allowed */
    write_virtual_word(BX_SEG_REG_ES, edi, &value16);
    incr = 2;
  }

#if BX_SupportRepeatSpeedups
#if (BX_DEBUGGER == 0)
#if (defined(__i386__) && __i386__)
doIncr:
#endif
#endif
#endif

#if BX_SUPPORT_X86_64
  if (i->as64L()) {
    if (BX_CPU_THIS_PTR get_DF ())
      RDI = RDI - incr;
    else
      RDI = RDI + incr;
  }
  else
#endif
  if (i->as32L()) {
    if (BX_CPU_THIS_PTR get_DF ())
      RDI = EDI - incr;
    else
      RDI = EDI + incr;
  }
  else {
    if (BX_CPU_THIS_PTR get_DF ())
      DI = DI - incr;
    else
      DI = DI + incr;
  }
}

void BX_CPU_C::OUTSB_DXXb(bxInstruction_c *i)
{
  unsigned seg;
  Bit8u value8;
  bx_address esi;

  if (BX_CPU_THIS_PTR cr0.pe && (BX_CPU_THIS_PTR get_VM () || (CPL>BX_CPU_THIS_PTR get_IOPL ()))) {
    if ( !BX_CPU_THIS_PTR allow_io(DX, 1) ) {
      exception(BX_GP_EXCEPTION, 0, 0);
    }
  }

  if (!BX_NULL_SEG_REG(i->seg())) {
    seg = i->seg();
  }
  else {
    seg = BX_SEG_REG_DS;
  }

#if BX_SUPPORT_X86_64
  if (i->as64L())
    esi = RSI;
  else
#endif
  if (i->as32L())
    esi = ESI;
  else
    esi = SI;

  read_virtual_byte(seg, esi, &value8);

  BX_OUTP(DX, value8, 1);

#if BX_SUPPORT_X86_64
  if (i->as64L()) {
    if (BX_CPU_THIS_PTR get_DF ())
      RSI--;
    else
      RSI++;
  }
  else
#endif
  if (i->as32L()) {
    if (BX_CPU_THIS_PTR get_DF ())
      RSI--;
    else
      RSI++;
  }
  else {
    if (BX_CPU_THIS_PTR get_DF ())
      SI--;
    else
      SI++;
  }
}

// output word/doubleword string to port
void BX_CPU_C::OUTSW_DXXv(bxInstruction_c *i)
{
  unsigned seg;
  bx_address esi;
  unsigned int incr;

  if (!BX_NULL_SEG_REG(i->seg())) {
    seg = i->seg();
  }
  else {
    seg = BX_SEG_REG_DS;
  }

#if BX_SUPPORT_X86_64
  if (i->as64L())
    esi = RSI;
  else
#endif
  if (i->as32L())
    esi = ESI;
  else
    esi = SI;

  if (i->os32L()) {
    Bit32u value32;

    if (BX_CPU_THIS_PTR cr0.pe && (BX_CPU_THIS_PTR get_VM () || (CPL>BX_CPU_THIS_PTR get_IOPL ()))) {
      if ( !BX_CPU_THIS_PTR allow_io(DX, 4) ) {
        exception(BX_GP_EXCEPTION, 0, 0);
      }
    }

    read_virtual_dword(seg, esi, &value32);

    BX_OUTP(DX, value32, 4);
    incr = 4;
  }
  else {
    Bit16u value16;

    if (BX_CPU_THIS_PTR cr0.pe && (BX_CPU_THIS_PTR get_VM () || (CPL>BX_CPU_THIS_PTR get_IOPL ()))) {
      if ( !BX_CPU_THIS_PTR allow_io(DX, 2) ) {
        exception(BX_GP_EXCEPTION, 0, 0);
      }
    }

#if BX_SupportRepeatSpeedups
#if (BX_DEBUGGER == 0)
#if (defined(__i386__) && __i386__)
    /* If conditions are right, we can transfer IO to physical memory
     * in a batch, rather than one instruction at a time.
     */
    if (i->repUsedL() && !BX_CPU_THIS_PTR async_event) {
      Bit32u wordCount;

#if BX_SUPPORT_X86_64
      if (i->as64L())
        wordCount = RCX; // Truncated to 32bits. (we're only doing 1 page)
      else
#endif
      if (i->as32L())
        wordCount = ECX;
      else
        wordCount = CX;

      if (wordCount) {
        bx_address laddrSrc;
        Bit32u paddrSrc, wordsFitSrc;
        Bit8u *hostAddrSrc;
        bx_segment_reg_t *srcSegPtr;
        unsigned pointerDelta;

        srcSegPtr = &BX_CPU_THIS_PTR sregs[seg];

        // Do segment checks for the 1st word.  We do not want to
        // trip an exception beyond this, because the address would
        // be incorrect.  After we know how many bytes we will directly
        // transfer, we can do the full segment limit check ourselves
        // without generating an exception.
        read_virtual_checks(srcSegPtr, esi, 2);
        laddrSrc = BX_CPU_THIS_PTR get_segment_base(seg) + esi;
        if (BX_CPU_THIS_PTR cr0.pg)
          paddrSrc = dtranslate_linear(laddrSrc, CPL==3, BX_READ);
        else
          paddrSrc = laddrSrc;
        // If we want to write directly into the physical memory array,
        // we need the A20 address.
        paddrSrc = A20ADDR(paddrSrc);

        hostAddrSrc = BX_CPU_THIS_PTR mem->getHostMemAddr(BX_CPU_THIS,
            paddrSrc, BX_READ, DATA_ACCESS);

        // Check that native host access was not vetoed for that page, and
        // that the address is word aligned.
        if ( hostAddrSrc && ! (paddrSrc & 1) ) {
          // See how many words can fit in the rest of this page.
          if (BX_CPU_THIS_PTR get_DF ()) {
            // Counting downward.
            // Note: 1st word must not cross page boundary.
            if ( (paddrSrc & 0xfff) > 0xffe )
              goto noAcceleration;
            wordsFitSrc = (2 + (paddrSrc & 0xfff)) >> 1;
            pointerDelta = (unsigned) -2;
          }
          else {
            // Counting upward.
            wordsFitSrc = (0x1000 - (paddrSrc & 0xfff)) >> 1;
            pointerDelta =  2;
          }

          // Restrict word count to the number that will fit in this page.
          if (wordCount > wordsFitSrc)
            wordCount = wordsFitSrc;

          // If after all the restrictions, there is anything left to do...
          if (wordCount) {
            unsigned j;
            Bit32u srcSegLimit;

            srcSegLimit = srcSegPtr->cache.u.segment.limit_scaled;
            // For 16-bit addressing mode, clamp the segment limits to 16bits
            // so we don't have to worry about computations using si/di
            // rolling over 16-bit boundaries.
            if (!i->as32L()) {
              if (srcSegLimit > 0xffff)
                srcSegLimit = 0xffff;
            }

            // Before we copy memory, we need to make sure that the segments
            // allow the accesses up to the given source and dest offset.  If
            // the cache.valid bits have SegAccessWOK and ROK, we know that
            // the cache is valid for those operations, and that the segments
            // are non-expand down (thus we can make a simple limit check).
            if ( !(srcSegPtr->cache.valid & SegAccessROK) ) {
              goto noAcceleration;
            }
            if (BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64) {
              // Now make sure transfer will fit within the constraints of the
              // segment boundaries, 0..limit for non expand-down.  We know
              // wordCount >= 1 here.
              if (BX_CPU_THIS_PTR get_DF ()) {
                // Counting downward.
                Bit32u minOffset = (wordCount-1) << 1;
                if ( esi < minOffset )
                  goto noAcceleration;
              }
              else {
                // Counting upward.
                Bit32u srcMaxOffset = (srcSegLimit - (wordCount<<1)) + 1;
                if ( esi > srcMaxOffset )
                  goto noAcceleration;
              }
            }

            for (j=0; j<wordCount; ) {
              Bit16u temp16;
              bx_devices.bulkIOQuantumsTransferred = 0;
              if ( BX_CPU_THIS_PTR get_DF ()==0 ) { // Only do accel for DF=0
                bx_devices.bulkIOHostAddr = hostAddrSrc;
                bx_devices.bulkIOQuantumsRequested = (wordCount - j);
              }
              else
                bx_devices.bulkIOQuantumsRequested = 0;
              temp16 = * (Bit16u *) hostAddrSrc;
              BX_OUTP(DX, temp16, 2);
              if ( bx_devices.bulkIOQuantumsTransferred ) {
                hostAddrSrc =  bx_devices.bulkIOHostAddr;
                j += bx_devices.bulkIOQuantumsTransferred;
              }
              else {
                hostAddrSrc += pointerDelta;
                j++;
              }
              // Terminate early if there was an event.
              if ( BX_CPU_THIS_PTR async_event )
                break;
            }
            // Reset for next non-bulk IO.
            bx_devices.bulkIOQuantumsRequested = 0;
            wordCount = j;
            // Decrement eCX.  Note, the main loop will decrement 1 also, so
            // decrement by one less than expected, like the case above.
            BX_TICKN(j-1); // Main cpu loop also decrements one more.
#if BX_SUPPORT_X86_64
            if (i->as64L())
              RCX -= (wordCount-1);
            else
#endif
            if (i->as32L())
              ECX -= (wordCount-1);
            else
              CX  -= (wordCount-1);
            incr = wordCount << 1; // count * 2.
            goto doIncr;
          }
        }
      }
    }

noAcceleration:

#endif // __i386__
#endif  // (BX_DEBUGGER == 0)
#endif  // #if BX_SupportRepeatSpeedups

    read_virtual_word(seg, esi, &value16);

    BX_OUTP(DX, value16, 2);
    incr = 2;
  }

#if BX_SupportRepeatSpeedups
#if (BX_DEBUGGER == 0)
#if (defined(__i386__) && __i386__)
doIncr:
#endif
#endif
#endif

#if BX_SUPPORT_X86_64
  if (i->as64L()) {
    if (BX_CPU_THIS_PTR get_DF ())
      RSI = RSI - incr;
    else
      RSI = RSI + incr;
  }
  else
#endif
  if (i->as32L()) {
    if (BX_CPU_THIS_PTR get_DF ())
      RSI = ESI - incr;
    else
      RSI = ESI + incr;
  }
  else {
    if (BX_CPU_THIS_PTR get_DF ())
      SI = SI - incr;
    else
      SI = SI + incr;
  }
}

void BX_CPU_C::IN_ALIb(bxInstruction_c *i)
{
  AL = BX_CPU_THIS_PTR inp8(i->Ib());
}

void BX_CPU_C::IN_eAXIb(bxInstruction_c *i)
{
#if BX_CPU_LEVEL > 2
  if (i->os32L()) {
    Bit32u eax = BX_CPU_THIS_PTR inp32(i->Ib());
    RAX = eax;
  }
  else
#endif /* BX_CPU_LEVEL > 2 */
  {
    AX = BX_CPU_THIS_PTR inp16(i->Ib());
  }
}

void BX_CPU_C::OUT_IbAL(bxInstruction_c *i)
{
  BX_CPU_THIS_PTR outp8(i->Ib(), AL);
}

void BX_CPU_C::OUT_IbeAX(bxInstruction_c *i)
{
#if BX_CPU_LEVEL > 2
  if (i->os32L()) {
    BX_CPU_THIS_PTR outp32(i->Ib(), EAX);
  }
  else
#endif /* BX_CPU_LEVEL > 2 */
  {
    BX_CPU_THIS_PTR outp16(i->Ib(), AX);
  }
}

void BX_CPU_C::IN_ALDX(bxInstruction_c *i)
{
  AL = BX_CPU_THIS_PTR inp8(DX);
}

void BX_CPU_C::IN_eAXDX(bxInstruction_c *i)
{
#if BX_CPU_LEVEL > 2
  if (i->os32L()) {
    Bit32u eax = BX_CPU_THIS_PTR inp32(DX);
    RAX = eax;
  }
  else
#endif /* BX_CPU_LEVEL > 2 */
  {
    AX = BX_CPU_THIS_PTR inp16(DX);
  }
}

void BX_CPU_C::OUT_DXAL(bxInstruction_c *i)
{
  BX_CPU_THIS_PTR outp8(DX, AL);
}

void BX_CPU_C::OUT_DXeAX(bxInstruction_c *i)
{
#if BX_CPU_LEVEL > 2
  if (i->os32L()) {
    BX_CPU_THIS_PTR outp32(DX, EAX);
  }
  else
#endif /* BX_CPU_LEVEL > 2 */
  {
    BX_CPU_THIS_PTR outp16(DX, AX);
  }
}