/*
 *                   XFree86 int10 module
 *   execute BIOS int 10h calls in x86 real mode environment
 *                 Copyright 1999 Egbert Eich
 */

#ifdef HAVE_XORG_CONFIG_H
#include <xorg-config.h>
#endif

#include "xf86.h"
#include "compiler.h"
#define _INT10_PRIVATE
#include "xf86int10.h"
#include "int10Defines.h"
#include "Pci.h"

#define REG pInt

xf86Int10InfoPtr Int10Current = NULL;

static int int1A_handler(xf86Int10InfoPtr pInt);

#ifndef _PC
static int int42_handler(xf86Int10InfoPtr pInt);
#endif
static int intE6_handler(xf86Int10InfoPtr pInt);
static struct pci_device *findPci(xf86Int10InfoPtr pInt, unsigned short bx);
static CARD32 pciSlotBX(const struct pci_device *pvp);

int
int_handler(xf86Int10InfoPtr pInt)
{
    int num = pInt->num;
    int ret = 0;

    switch (num) {
#ifndef _PC
    case 0x10:
    case 0x42:
    case 0x6D:
        if (getIntVect(pInt, num) == I_S_DEFAULT_INT_VECT)
            ret = int42_handler(pInt);
        break;
#endif
    case 0x1A:
        ret = int1A_handler(pInt);
        break;
    case 0xe6:
        ret = intE6_handler(pInt);
        break;
    default:
        break;
    }

    if (!ret)
        ret = run_bios_int(num, pInt);

    if (!ret) {
        xf86DrvMsg(pInt->pScrn->scrnIndex, X_ERROR, "Halting on int 0x%2.2x!\n", num);
        dump_registers(pInt);
        stack_trace(pInt);
    }

    return ret;
}

#ifndef _PC
/*
 * This is derived from a number of PC system BIOS'es.  The intent here is to
 * provide very primitive video support, before an EGA/VGA BIOS installs its
 * own interrupt vector.  Here, "Ignored" calls should remain so.  "Not
 * Implemented" denotes functionality that can be implemented should the need
 * arise.  What are "Not Implemented" throughout are video memory accesses.
 * Also, very little input validity checking is done here.
 */
static int
int42_handler(xf86Int10InfoPtr pInt)
{
    switch (X86_AH) {
    case 0x00:
        /* Set Video Mode                                     */
        /* Enter:  AL = video mode number                     */
        /* Leave:  Nothing                                    */
        /* Implemented (except for clearing the screen)       */
    {                           /* Localise */
        unsigned int ioport;
        int i;
        CARD16 int1d, regvals, tmp;
        CARD8 mode, cgamode, cgacolour;

        /*
         * Ignore all mode numbers but 0x00-0x13.  Some systems also ignore
         * 0x0B and 0x0C, but don't do that here.
         */
        if (X86_AL > 0x13)
            break;

        /*
         * You didn't think that was really the mode set, did you?  There
         * are only so many slots in the video parameter table...
         */
        mode = X86_AL;
        ioport = 0x03D4;
        switch (MEM_RB(pInt, 0x0410) & 0x30) {
        case 0x30:             /* MDA */
            mode = 0x07;        /* Force mode to 0x07 */
            ioport = 0x03B4;
            break;
        case 0x10:             /* CGA 40x25 */
            if (mode >= 0x07)
                mode = 0x01;
            break;
        case 0x20:             /* CGA 80x25 (MCGA?) */
            if (mode >= 0x07)
                mode = 0x03;
            break;
        case 0x00:             /* EGA/VGA */
            if (mode >= 0x07)   /* Don't try MDA timings */
                mode = 0x01;    /* !?!?! */
            break;
        }

        /* Locate data in video parameter table */
        int1d = MEM_RW(pInt, 0x1d << 2);
        regvals = ((mode >> 1) << 4) + int1d;
        cgacolour = 0x30;
        if (mode == 0x06) {
            regvals -= 0x10;
            cgacolour = 0x3F;
        }

            /** Update BIOS Data Area **/

        /* Video mode */
        MEM_WB(pInt, 0x0449, mode);

        /* Columns */
        tmp = MEM_RB(pInt, mode + int1d + 0x48);
        MEM_WW(pInt, 0x044A, tmp);

        /* Page length */
        tmp = MEM_RW(pInt, (mode & 0x06) + int1d + 0x40);
        MEM_WW(pInt, 0x044C, tmp);

        /* Start Address */
        MEM_WW(pInt, 0x044E, 0);

        /* Cursor positions, one for each display page */
        for (i = 0x0450; i < 0x0460; i += 2)
            MEM_WW(pInt, i, 0);

        /* Cursor start & end scanlines */
        tmp = MEM_RB(pInt, regvals + 0x0B);
        MEM_WB(pInt, 0x0460, tmp);
        tmp = MEM_RB(pInt, regvals + 0x0A);
        MEM_WB(pInt, 0x0461, tmp);

        /* Current display page number */
        MEM_WB(pInt, 0x0462, 0);

        /* CRTC I/O address */
        MEM_WW(pInt, 0x0463, ioport);

        /* CGA Mode register value */
        cgamode = MEM_RB(pInt, mode + int1d + 0x50);
        MEM_WB(pInt, 0x0465, cgamode);

        /* CGA Colour register value */
        MEM_WB(pInt, 0x0466, cgacolour);

        /* Rows */
        MEM_WB(pInt, 0x0484, (25 - 1));

        /* Program the mode */
        pci_io_write8(pInt->io, ioport + 4, cgamode & 0x37);    /* Turn off screen */
        for (i = 0; i < 0x10; i++) {
            tmp = MEM_RB(pInt, regvals + i);
            pci_io_write8(pInt->io, ioport, i);
            pci_io_write8(pInt->io, ioport + 1, tmp);
        }
        pci_io_write8(pInt->io, ioport + 5, cgacolour); /* Select colour mode */
        pci_io_write8(pInt->io, ioport + 4, cgamode);   /* Turn on screen */
    }
        break;

    case 0x01:
        /* Set Cursor Type                                    */
        /* Enter:  CH = starting line for cursor              */
        /*         CL = ending line for cursor                */
        /* Leave:  Nothing                                    */
        /* Implemented                                        */
    {                           /* Localise */
        unsigned int ioport = MEM_RW(pInt, 0x0463);

        MEM_WB(pInt, 0x0460, X86_CL);
        MEM_WB(pInt, 0x0461, X86_CH);

        pci_io_write8(pInt->io, ioport, 0x0A);
        pci_io_write8(pInt->io, ioport + 1, X86_CH);
        pci_io_write8(pInt->io, ioport, 0x0B);
        pci_io_write8(pInt->io, ioport + 1, X86_CL);
    }
        break;

    case 0x02:
        /* Set Cursor Position                                */
        /* Enter:  BH = display page number                   */
        /*         DH = row                                   */
        /*         DL = column                                */
        /* Leave:  Nothing                                    */
        /* Implemented                                        */
    {                           /* Localise */
        unsigned int ioport;
        CARD16 offset;

        MEM_WB(pInt, (X86_BH << 1) + 0x0450, X86_DL);
        MEM_WB(pInt, (X86_BH << 1) + 0x0451, X86_DH);

        if (X86_BH != MEM_RB(pInt, 0x0462))
            break;

        offset = (X86_DH * MEM_RW(pInt, 0x044A)) + X86_DL;
        offset += MEM_RW(pInt, 0x044E) << 1;

        ioport = MEM_RW(pInt, 0x0463);
        pci_io_write8(pInt->io, ioport, 0x0E);
        pci_io_write8(pInt->io, ioport + 1, offset >> 8);
        pci_io_write8(pInt->io, ioport, 0x0F);
        pci_io_write8(pInt->io, ioport + 1, offset & 0xFF);
    }
        break;

    case 0x03:
        /* Get Cursor Position                                */
        /* Enter:  BH = display page number                   */
        /* Leave:  CH = starting line for cursor              */
        /*         CL = ending line for cursor                */
        /*         DH = row                                   */
        /*         DL = column                                */
        /* Implemented                                        */
    {                           /* Localise */
        X86_CL = MEM_RB(pInt, 0x0460);
        X86_CH = MEM_RB(pInt, 0x0461);
        X86_DL = MEM_RB(pInt, (X86_BH << 1) + 0x0450);
        X86_DH = MEM_RB(pInt, (X86_BH << 1) + 0x0451);
    }
        break;

    case 0x04:
        /* Get Light Pen Position                             */
        /* Enter:  Nothing                                    */
        /* Leave:  AH = 0x01 (down/triggered) or 0x00 (not)   */
        /*         BX = pixel column                          */
        /*         CX = pixel row                             */
        /*         DH = character row                         */
        /*         DL = character column                      */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x04) -- Get Light Pen Position\n",
                       pInt->num);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
        X86_AH = X86_BX = X86_CX = X86_DX = 0;
    }
        break;

    case 0x05:
        /* Set Display Page                                   */
        /* Enter:  AL = display page number                   */
        /* Leave:  Nothing                                    */
        /* Implemented                                        */
    {                           /* Localise */
        unsigned int ioport = MEM_RW(pInt, 0x0463);
        CARD16 start;
        CARD8 x, y;

        /* Calculate new start address */
        MEM_WB(pInt, 0x0462, X86_AL);
        start = X86_AL * MEM_RW(pInt, 0x044C);
        MEM_WW(pInt, 0x044E, start);
        start <<= 1;

        /* Update start address */
        pci_io_write8(pInt->io, ioport, 0x0C);
        pci_io_write8(pInt->io, ioport + 1, start >> 8);
        pci_io_write8(pInt->io, ioport, 0x0D);
        pci_io_write8(pInt->io, ioport + 1, start & 0xFF);

        /* Switch cursor position */
        y = MEM_RB(pInt, (X86_AL << 1) + 0x0450);
        x = MEM_RB(pInt, (X86_AL << 1) + 0x0451);
        start += (y * MEM_RW(pInt, 0x044A)) + x;

        /* Update cursor position */
        pci_io_write8(pInt->io, ioport, 0x0E);
        pci_io_write8(pInt->io, ioport + 1, start >> 8);
        pci_io_write8(pInt->io, ioport, 0x0F);
        pci_io_write8(pInt->io, ioport + 1, start & 0xFF);
    }
        break;

    case 0x06:
        /* Initialise or Scroll Window Up                     */
        /* Enter:  AL = lines to scroll up                    */
        /*         BH = attribute for blank                   */
        /*         CH = upper y of window                     */
        /*         CL = left x of window                      */
        /*         DH = lower y of window                     */
        /*         DL = right x of window                     */
        /* Leave:  Nothing                                    */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x06) -- Initialise or Scroll Window Up\n",
                       pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       " AL=0x%2.2x, BH=0x%2.2x,"
                       " CH=0x%2.2x, CL=0x%2.2x, DH=0x%2.2x, DL=0x%2.2x\n",
                       X86_AL, X86_BH, X86_CH, X86_CL, X86_DH, X86_DL);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
    }
        break;

    case 0x07:
        /* Initialise or Scroll Window Down                   */
        /* Enter:  AL = lines to scroll down                  */
        /*         BH = attribute for blank                   */
        /*         CH = upper y of window                     */
        /*         CL = left x of window                      */
        /*         DH = lower y of window                     */
        /*         DL = right x of window                     */
        /* Leave:  Nothing                                    */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x07) -- Initialise or Scroll Window Down\n",
                       pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       " AL=0x%2.2x, BH=0x%2.2x,"
                       " CH=0x%2.2x, CL=0x%2.2x, DH=0x%2.2x, DL=0x%2.2x\n",
                       X86_AL, X86_BH, X86_CH, X86_CL, X86_DH, X86_DL);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
    }
        break;

    case 0x08:
        /* Read Character and Attribute at Cursor             */
        /* Enter:  BH = display page number                   */
        /* Leave:  AH = attribute                             */
        /*         AL = character                             */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x08) -- Read Character and Attribute at"
                       " Cursor\n", pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       "BH=0x%2.2x\n", X86_BH);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
        X86_AX = 0;
    }
        break;

    case 0x09:
        /* Write Character and Attribute at Cursor            */
        /* Enter:  AL = character                             */
        /*         BH = display page number                   */
        /*         BL = attribute (text) or colour (graphics) */
        /*         CX = replication count                     */
        /* Leave:  Nothing                                    */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x09) -- Write Character and Attribute at"
                       " Cursor\n", pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       "AL=0x%2.2x, BH=0x%2.2x, BL=0x%2.2x, CX=0x%4.4x\n",
                       X86_AL, X86_BH, X86_BL, X86_CX);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
    }
        break;

    case 0x0a:
        /* Write Character at Cursor                          */
        /* Enter:  AL = character                             */
        /*         BH = display page number                   */
        /*         BL = colour                                */
        /*         CX = replication count                     */
        /* Leave:  Nothing                                    */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x0A) -- Write Character at Cursor\n",
                       pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       "AL=0x%2.2x, BH=0x%2.2x, BL=0x%2.2x, CX=0x%4.4x\n",
                       X86_AL, X86_BH, X86_BL, X86_CX);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
    }
        break;

    case 0x0b:
        /* Set Palette, Background or Border                  */
        /* Enter:  BH = 0x00 or 0x01                          */
        /*         BL = colour or palette (respectively)      */
        /* Leave:  Nothing                                    */
        /* Implemented                                        */
    {                           /* Localise */
        unsigned int ioport = MEM_RW(pInt, 0x0463) + 5;
        CARD8 cgacolour = MEM_RB(pInt, 0x0466);

        if (X86_BH) {
            cgacolour &= 0xDF;
            cgacolour |= (X86_BL & 0x01) << 5;
        }
        else {
            cgacolour &= 0xE0;
            cgacolour |= X86_BL & 0x1F;
        }

        MEM_WB(pInt, 0x0466, cgacolour);
        pci_io_write8(pInt->io, ioport, cgacolour);
    }
        break;

    case 0x0c:
        /* Write Graphics Pixel                               */
        /* Enter:  AL = pixel value                           */
        /*         BH = display page number                   */
        /*         CX = column                                */
        /*         DX = row                                   */
        /* Leave:  Nothing                                    */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x0C) -- Write Graphics Pixel\n",
                       pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       "AL=0x%2.2x, BH=0x%2.2x, CX=0x%4.4x, DX=0x%4.4x\n",
                       X86_AL, X86_BH, X86_CX, X86_DX);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
    }
        break;

    case 0x0d:
        /* Read Graphics Pixel                                */
        /* Enter:  BH = display page number                   */
        /*         CX = column                                */
        /*         DX = row                                   */
        /* Leave:  AL = pixel value                           */
        /* Not Implemented                                    */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x0D) -- Read Graphics Pixel\n",
                       pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       "BH=0x%2.2x, CX=0x%4.4x, DX=0x%4.4x\n", X86_BH, X86_CX,
                       X86_DX);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
        X86_AL = 0;
    }
        break;

    case 0x0e:
        /* Write Character in Teletype Mode                   */
        /* Enter:  AL = character                             */
        /*         BH = display page number                   */
        /*         BL = foreground colour                     */
        /* Leave:  Nothing                                    */
        /* Not Implemented                                    */
        /* WARNING:  Emulation of BEL characters will require */
        /*           emulation of RTC and PC speaker I/O.     */
        /*           Also, this recurses through int 0x10     */
        /*           which might or might not have been       */
        /*           installed yet.                           */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x0E) -- Write Character in Teletype Mode\n",
                       pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       "AL=0x%2.2x, BH=0x%2.2x, BL=0x%2.2x\n",
                       X86_AL, X86_BH, X86_BL);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
    }
        break;

    case 0x0f:
        /* Get Video Mode                                     */
        /* Enter:  Nothing                                    */
        /* Leave:  AH = number of columns                     */
        /*         AL = video mode number                     */
        /*         BH = display page number                   */
        /* Implemented                                        */
    {                           /* Localise */
        X86_AH = MEM_RW(pInt, 0x044A);
        X86_AL = MEM_RB(pInt, 0x0449);
        X86_BH = MEM_RB(pInt, 0x0462);
    }
        break;

    case 0x10:
        /* Colour Control (subfunction in AL)                 */
        /* Enter:  Various                                    */
        /* Leave:  Various                                    */
        /* Ignored                                            */
        break;

    case 0x11:
        /* Font Control (subfunction in AL)                   */
        /* Enter:  Various                                    */
        /* Leave:  Various                                    */
        /* Ignored                                            */
        break;

    case 0x12:
        /* Miscellaneous (subfunction in BL)                  */
        /* Enter:  Various                                    */
        /* Leave:  Various                                    */
        /* Ignored.  Previous code here optionally allowed    */
        /* the enabling and disabling of VGA, but no system   */
        /* BIOS I've come across actually implements it.      */
        break;

    case 0x13:
        /* Write String in Teletype Mode                      */
        /* Enter:  AL = write mode                            */
        /*         BL = attribute (if (AL & 0x02) == 0)       */
        /*         CX = string length                         */
        /*         DH = row                                   */
        /*         DL = column                                */
        /*         ES:BP = string segment:offset              */
        /* Leave:  Nothing                                    */
        /* Not Implemented                                    */
        /* WARNING:  Emulation of BEL characters will require */
        /*           emulation of RTC and PC speaker I/O.     */
        /*           Also, this recurses through int 0x10     */
        /*           which might or might not have been       */
        /*           installed yet.                           */
    {                           /* Localise */
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x%2.2x(AH=0x13) -- Write String in Teletype Mode\n",
                       pInt->num);
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 3,
                       "AL=0x%2.2x, BL=0x%2.2x, CX=0x%4.4x,"
                       " DH=0x%2.2x, DL=0x%2.2x, ES:BP=0x%4.4x:0x%4.4x\n",
                       X86_AL, X86_BL, X86_CX, X86_DH, X86_DL, X86_ES, X86_BP);
        if (xf86GetVerbosity() > 3) {
            dump_registers(pInt);
            stack_trace(pInt);
        }
    }
        break;

    default:
        /* Various extensions                                 */
        /* Enter:  Various                                    */
        /* Leave:  Various                                    */
        /* Ignored                                            */
        break;
    }

    return 1;
}
#endif

#define SUCCESSFUL              0x00
#define DEVICE_NOT_FOUND        0x86
#define BAD_REGISTER_NUMBER     0x87

#ifdef SHOW_ALL_DEVICES
/**
 * These functions are meant to be used by the PCI BIOS emulation. Some
 * BIOSes need to see if there are \b other chips of the same type around so
 * by setting \c exclude one PCI device can be explicitely excluded, if
 * required.
 */
static struct pci_device *
do_find(const struct pci_id_match *m, char n, const struct pci_device *exclude)
{
    struct pci_device *dev;
    struct pci_device_iterator *iter;

    n++;

    iter = pci_id_match_iterator_create(m);
    while ((dev = pci_device_next(iter)) != NULL) {
        if ((dev != exclude) && !(--n)) {
            break;
        }
    }

    pci_iterator_destroy(iter);

    return dev;
}

static struct pci_device *
find_pci_device_vendor(CARD16 vendorID, CARD16 deviceID,
                       char n, const struct pci_device *exclude)
{
    struct pci_id_match m;

    m.vendor_id = vendorID;
    m.device_id = deviceID;
    m.subvendor_id = PCI_MATCH_ANY;
    m.subdevice_id = PCI_MATCH_ANY;
    m.device_class = 0;
    m.device_class_mask = 0;

    return do_find(&m, n, exclude);
}

static struct pci_device *
find_pci_class(CARD8 intf, CARD8 subClass, CARD16 _class,
               char n, const struct pci_device *exclude)
{
    struct pci_id_match m;

    m.vendor_id = PCI_MATCH_ANY;
    m.device_id = PCI_MATCH_ANY;
    m.subvendor_id = PCI_MATCH_ANY;
    m.subdevice_id = PCI_MATCH_ANY;
    m.device_class = (((uint32_t) _class) << 16)
        | (((uint32_t) subClass) << 8) | intf;
    m.device_class_mask = 0x00ffffff;

    return do_find(&m, n, exclude);
}
#endif

/*
 * Return the last bus number in the same domain as dev.  Only look at the
 * one domain since this is going into %cl, and VGA I/O is per-domain anyway.
 */
static int
int1A_last_bus_number(struct pci_device *dev)
{
    struct pci_device *d;

    struct pci_slot_match m = { dev->domain,
        PCI_MATCH_ANY,
        PCI_MATCH_ANY,
        PCI_MATCH_ANY
    };
    struct pci_device_iterator *iter;
    int i = 0;

    iter = pci_slot_match_iterator_create(&m);

    while ((d = pci_device_next(iter)))
        if (d->bus > i)
            i = d->bus;

    pci_iterator_destroy(iter);

    return i;
}

static int
int1A_handler(xf86Int10InfoPtr pInt)
{
    struct pci_device *const pvp = xf86GetPciInfoForEntity(pInt->entityIndex);
    struct pci_device *dev;

    if (pvp == NULL)
        return 0;               /* oops */

#ifdef PRINT_INT
    ErrorF("int 0x1a: ax=0x%x bx=0x%x cx=0x%x dx=0x%x di=0x%x es=0x%x\n",
           X86_EAX, X86_EBX, X86_ECX, X86_EDX, X86_EDI, X86_ESI);
#endif
    switch (X86_AX) {
    case 0xb101:
        X86_EAX &= 0xFF00;      /* no config space/special cycle support */
        X86_EDX = 0x20494350;   /* " ICP" */
        X86_EBX = 0x0210;       /* Version 2.10 */
        X86_ECX &= 0xFF00;
        X86_ECX |= int1A_last_bus_number(pvp);
        X86_EFLAGS &= ~((unsigned long) 0x01);  /* clear carry flag */
#ifdef PRINT_INT
        ErrorF("ax=0x%x dx=0x%x bx=0x%x cx=0x%x flags=0x%x\n",
               X86_EAX, X86_EDX, X86_EBX, X86_ECX, X86_EFLAGS);
#endif
        return 1;
    case 0xb102:
        if ((X86_DX == pvp->vendor_id)
            && (X86_CX == pvp->device_id)
            && (X86_ESI == 0)) {
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
            X86_EBX = pciSlotBX(pvp);
        }
#ifdef SHOW_ALL_DEVICES
        else if ((dev = find_pci_device_vendor(X86_EDX, X86_ECX, X86_ESI, pvp))) {
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
            X86_EBX = pciSlotBX(dev);
        }
#endif
        else {
            X86_EAX = X86_AL | (DEVICE_NOT_FOUND << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x bx=0x%x flags=0x%x\n", X86_EAX, X86_EBX, X86_EFLAGS);
#endif
        return 1;
    case 0xb103:
        if ((X86_ECX & 0x00FFFFFF) == pvp->device_class) {
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EBX = pciSlotBX(pvp);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
        }
#ifdef SHOW_ALL_DEVICES
        else if ((dev = find_pci_class(X86_CL, X86_CH,
                                       (X86_ECX & 0xffff0000) >> 16,
                                       X86_ESI, pvp))) {
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
            X86_EBX = pciSlotBX(dev);
        }
#endif
        else {
            X86_EAX = X86_AL | (DEVICE_NOT_FOUND << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x flags=0x%x\n", X86_EAX, X86_EFLAGS);
#endif
        return 1;
    case 0xb108:
        if ((dev = findPci(pInt, X86_EBX)) != NULL) {
            pci_device_cfg_read_u8(dev, &X86_CL, X86_DI);
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
        }
        else {
            X86_EAX = X86_AL | (BAD_REGISTER_NUMBER << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x cx=0x%x flags=0x%x\n", X86_EAX, X86_ECX, X86_EFLAGS);
#endif
        return 1;
    case 0xb109:
        if ((dev = findPci(pInt, X86_EBX)) != NULL) {
            pci_device_cfg_read_u16(dev, &X86_CX, X86_DI);
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
        }
        else {
            X86_EAX = X86_AL | (BAD_REGISTER_NUMBER << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x cx=0x%x flags=0x%x\n", X86_EAX, X86_ECX, X86_EFLAGS);
#endif
        return 1;
    case 0xb10a:
        if ((dev = findPci(pInt, X86_EBX)) != NULL) {
            pci_device_cfg_read_u32(dev, &X86_ECX, X86_DI);
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
        }
        else {
            X86_EAX = X86_AL | (BAD_REGISTER_NUMBER << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x cx=0x%x flags=0x%x\n", X86_EAX, X86_ECX, X86_EFLAGS);
#endif
        return 1;
    case 0xb10b:
        if ((dev = findPci(pInt, X86_EBX)) != NULL) {
            pci_device_cfg_write_u8(dev, X86_CL, X86_DI);
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
        }
        else {
            X86_EAX = X86_AL | (BAD_REGISTER_NUMBER << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x flags=0x%x\n", X86_EAX, X86_EFLAGS);
#endif
        return 1;
    case 0xb10c:
        if ((dev = findPci(pInt, X86_EBX)) != NULL) {
            pci_device_cfg_write_u16(dev, X86_CX, X86_DI);
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
        }
        else {
            X86_EAX = X86_AL | (BAD_REGISTER_NUMBER << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x flags=0x%x\n", X86_EAX, X86_EFLAGS);
#endif
        return 1;
    case 0xb10d:
        if ((dev = findPci(pInt, X86_EBX)) != NULL) {
            pci_device_cfg_write_u32(dev, X86_ECX, X86_DI);
            X86_EAX = X86_AL | (SUCCESSFUL << 8);
            X86_EFLAGS &= ~((unsigned long) 0x01);      /* clear carry flag */
        }
        else {
            X86_EAX = X86_AL | (BAD_REGISTER_NUMBER << 8);
            X86_EFLAGS |= ((unsigned long) 0x01);       /* set carry flag */
        }
#ifdef PRINT_INT
        ErrorF("ax=0x%x flags=0x%x\n", X86_EAX, X86_EFLAGS);
#endif
        return 1;
    default:
        xf86DrvMsgVerb(pInt->pScrn->scrnIndex, X_NOT_IMPLEMENTED, 2,
                       "int 0x1a subfunction\n");
        dump_registers(pInt);
        if (xf86GetVerbosity() > 3)
            stack_trace(pInt);
        return 0;
    }
}

static struct pci_device *
findPci(xf86Int10InfoPtr pInt, unsigned short bx)
{
    const unsigned bus = (bx >> 8) & 0x00FF;
    const unsigned dev = (bx >> 3) & 0x001F;
    const unsigned func = (bx) & 0x0007;

    return pci_device_find_by_slot(pInt->dev->domain, bus, dev, func);
}

static CARD32
pciSlotBX(const struct pci_device *pvp)
{
    return ((pvp->bus << 8) & 0x00FF00) | (pvp->dev << 3) | (pvp->func);
}

/*
 * handle initialization
 */
static int
intE6_handler(xf86Int10InfoPtr pInt)
{
    struct pci_device *pvp;

    if ((pvp = xf86GetPciInfoForEntity(pInt->entityIndex)))
        X86_AX = (pvp->bus << 8) | (pvp->dev << 3) | (pvp->func & 0x7);
    pushw(pInt, X86_CS);
    pushw(pInt, X86_IP);
    X86_CS = pInt->BIOSseg;
    X86_EIP = 0x0003;
    X86_ES = 0;                 /* standard pc es */
    return 1;
}
