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path: root/src/vesa.c
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#define DEBUG_VERB 2
/*
 * Copyright (c) 2000 by Conectiva S.A. (http://www.conectiva.com)
 * Copyright 2008 Red Hat, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * CONECTIVA LINUX BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * Except as contained in this notice, the name of Conectiva Linux shall
 * not be used in advertising or otherwise to promote the sale, use or other
 * dealings in this Software without prior written authorization from
 * Conectiva Linux.
 *
 * Authors: Paulo César Pereira de Andrade <pcpa@conectiva.com.br>
 *          David Dawes <dawes@xfree86.org>
 *          Adam Jackson <ajax@redhat.com>
 */

/*
 * TODO:
 * - Port to RANDR 1.2 setup to make mode selection slightly better
 * - Port to RANDR 1.2 to drop the old-school DGA junk
 * - VBE/SCI for secondary DDC method?
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>

#include "vesa.h"

/* All drivers initialising the SW cursor need this */
#include "mipointer.h"

/* All drivers implementing backing store need this */
#include "mibstore.h"

/* Colormap handling */
#include "micmap.h"
#include "xf86cmap.h"
#include "xf86Modes.h"

/* DPMS */
#ifdef HAVE_XEXTPROTO_71
#include <X11/extensions/dpmsconst.h>
#else
#define DPMS_SERVER
#include <X11/extensions/dpms.h>
#endif


/* Mandatory functions */
static const OptionInfoRec * VESAAvailableOptions(int chipid, int busid);
static void VESAIdentify(int flags);
static Bool VESAProbe(DriverPtr drv, int flags);
#ifdef XSERVER_LIBPCIACCESS
static Bool VESAPciProbe(DriverPtr drv, int entity_num,
     struct pci_device *dev, intptr_t match_data);
#endif
static Bool VESAPreInit(ScrnInfoPtr pScrn, int flags);
static Bool VESAScreenInit(int Index, ScreenPtr pScreen, int argc,
			   char **argv);
static Bool VESAEnterVT(int scrnIndex, int flags);
static void VESALeaveVT(int scrnIndex, int flags);
static Bool VESACloseScreen(int scrnIndex, ScreenPtr pScreen);
static Bool VESASaveScreen(ScreenPtr pScreen, int mode);

static Bool VESASwitchMode(int scrnIndex, DisplayModePtr pMode, int flags);
static Bool VESASetMode(ScrnInfoPtr pScrn, DisplayModePtr pMode);
static void VESAAdjustFrame(int scrnIndex, int x, int y, int flags);
static void VESAFreeScreen(int scrnIndex, int flags);
static void VESAFreeRec(ScrnInfoPtr pScrn);
static VESAPtr VESAGetRec(ScrnInfoPtr pScrn);

static void
VESADisplayPowerManagementSet(ScrnInfoPtr pScrn, int mode,
                int flags);

/* locally used functions */
#ifdef HAVE_ISA
static int VESAFindIsaDevice(GDevPtr dev);
#endif
static Bool VESAMapVidMem(ScrnInfoPtr pScrn);
static void VESAUnmapVidMem(ScrnInfoPtr pScrn);
static int VESABankSwitch(ScreenPtr pScreen, unsigned int iBank);
static void VESALoadPalette(ScrnInfoPtr pScrn, int numColors, int *indices,
			    LOCO *colors, VisualPtr pVisual);
static void SaveFonts(ScrnInfoPtr pScrn);
static void RestoreFonts(ScrnInfoPtr pScrn);
static Bool 
VESASaveRestore(ScrnInfoPtr pScrn, vbeSaveRestoreFunction function);

static void *
VESAWindowLinear(ScreenPtr pScreen, CARD32 row, CARD32 offset, int mode,
		 CARD32 *size, void *closure)
{
    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
    VESAPtr pVesa = VESAGetRec(pScrn);

    *size = pVesa->maxBytesPerScanline;
    return ((CARD8 *)pVesa->base + row * pVesa->maxBytesPerScanline + offset);
}

static void *
VESAWindowWindowed(ScreenPtr pScreen, CARD32 row, CARD32 offset, int mode,
		   CARD32 *size, void *closure)
{
    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
    VESAPtr pVesa = VESAGetRec(pScrn);
    VbeModeInfoBlock *data = ((VbeModeInfoData*)(pScrn->currentMode->Private))->data;
    int window;

    offset += pVesa->maxBytesPerScanline * row;
    window = offset / (data->WinGranularity * 1024);
    pVesa->windowAoffset = window * data->WinGranularity * 1024;
    VESABankSwitch(pScreen, window);
    *size = data->WinSize * 1024 - (offset - pVesa->windowAoffset);

    return (void *)((unsigned long)pVesa->base +
		    (offset - pVesa->windowAoffset));
}

static void
vesaUpdatePacked(ScreenPtr pScreen, shadowBufPtr pBuf)
{
    shadowUpdatePacked(pScreen, pBuf);
}

static Bool VESADGAInit(ScrnInfoPtr pScrn, ScreenPtr pScreen);

enum GenericTypes
{
    CHIP_VESA_GENERIC
};

#ifdef XSERVER_LIBPCIACCESS
static const struct pci_id_match vesa_device_match[] = {
    {
	PCI_MATCH_ANY, PCI_MATCH_ANY, PCI_MATCH_ANY, PCI_MATCH_ANY,
	0x00030000, 0x00ffffff, CHIP_VESA_GENERIC 
    },

    { 0, 0, 0 },
};
#endif
    
/* Supported chipsets */
static SymTabRec VESAChipsets[] =
{
    {CHIP_VESA_GENERIC, "vesa"},
    {-1,		 NULL}
};

#ifndef XSERVER_LIBPCIACCESS
static PciChipsets VESAPCIchipsets[] = {
  { CHIP_VESA_GENERIC, PCI_CHIP_VGA, RES_SHARED_VGA },
  { -1,		-1,	   RES_UNDEFINED },
};
#endif

#ifdef HAVE_ISA
static IsaChipsets VESAISAchipsets[] = {
  {CHIP_VESA_GENERIC, RES_EXCLUSIVE_VGA},
  {-1,		0 }
};
#endif


/* 
 * This contains the functions needed by the server after loading the
 * driver module.  It must be supplied, and gets added the driver list by
 * the Module Setup funtion in the dynamic case.  In the static case a
 * reference to this is compiled in, and this requires that the name of
 * this DriverRec be an upper-case version of the driver name.
 */
_X_EXPORT DriverRec VESA = {
    VESA_VERSION,
    VESA_DRIVER_NAME,
    VESAIdentify,
    VESAProbe,
    VESAAvailableOptions,
    NULL,
    0,
    NULL,

#ifdef XSERVER_LIBPCIACCESS
    vesa_device_match,
    VESAPciProbe
#endif
};


typedef enum {
    OPTION_SHADOW_FB,
    OPTION_DFLT_REFRESH,
    OPTION_MODESET_CLEAR_SCREEN
} VESAOpts;

static const OptionInfoRec VESAOptions[] = {
    { OPTION_SHADOW_FB,    "ShadowFB",		OPTV_BOOLEAN,	{0},	FALSE },
    { OPTION_DFLT_REFRESH, "DefaultRefresh",	OPTV_BOOLEAN,	{0},	FALSE },
    { OPTION_MODESET_CLEAR_SCREEN, "ModeSetClearScreen",
						OPTV_BOOLEAN,	{0},	FALSE },
    { -1,		   NULL,		OPTV_NONE,	{0},	FALSE }
};

#ifdef XFree86LOADER

/* Module loader interface */
static MODULESETUPPROTO(vesaSetup);

static XF86ModuleVersionInfo vesaVersionRec =
{
    VESA_DRIVER_NAME,
    MODULEVENDORSTRING,
    MODINFOSTRING1,
    MODINFOSTRING2,
    XORG_VERSION_CURRENT,
    VESA_MAJOR_VERSION, VESA_MINOR_VERSION, VESA_PATCHLEVEL,
    ABI_CLASS_VIDEODRV,			/* This is a video driver */
    ABI_VIDEODRV_VERSION,
    MOD_CLASS_VIDEODRV,
    {0, 0, 0, 0}
};

/*
 * This data is accessed by the loader.  The name must be the module name
 * followed by "ModuleData".
 */
_X_EXPORT XF86ModuleData vesaModuleData = { &vesaVersionRec, vesaSetup, NULL };

static pointer
vesaSetup(pointer Module, pointer Options, int *ErrorMajor, int *ErrorMinor)
{
    static Bool Initialised = FALSE;

    if (!Initialised)
    {
	Initialised = TRUE;
	xf86AddDriver(&VESA, Module, 1);
	return (pointer)TRUE;
    }

    if (ErrorMajor)
	*ErrorMajor = LDR_ONCEONLY;
    return (NULL);
}

#endif

static const OptionInfoRec *
VESAAvailableOptions(int chipid, int busid)
{
    return (VESAOptions);
}

static void
VESAIdentify(int flags)
{
    xf86PrintChipsets(VESA_NAME, "driver for VESA chipsets", VESAChipsets);
}

static VESAPtr
VESAGetRec(ScrnInfoPtr pScrn)
{
    if (!pScrn->driverPrivate)
	pScrn->driverPrivate = calloc(sizeof(VESARec), 1);

    return ((VESAPtr)pScrn->driverPrivate);
}

/* Only a little like VBESetModeParameters */
static void
VESASetModeParameters(vbeInfoPtr pVbe, DisplayModePtr vbemode,
		      DisplayModePtr ddcmode)
{
    VbeModeInfoData *data;
    int clock;

    data = (VbeModeInfoData *)vbemode->Private;

    data->block = calloc(sizeof(VbeCRTCInfoBlock), 1);
    data->block->HorizontalTotal = ddcmode->HTotal;
    data->block->HorizontalSyncStart = ddcmode->HSyncStart;
    data->block->HorizontalSyncEnd = ddcmode->HSyncEnd;
    data->block->VerticalTotal = ddcmode->VTotal;
    data->block->VerticalSyncStart = ddcmode->VSyncStart;
    data->block->VerticalSyncEnd = ddcmode->VSyncEnd;
    data->block->Flags = ((ddcmode->Flags & V_NHSYNC) ? CRTC_NHSYNC : 0) |
	                 ((ddcmode->Flags & V_NVSYNC) ? CRTC_NVSYNC : 0);
    data->block->PixelClock = ddcmode->Clock * 1000;

    /* ask the BIOS to figure out the real clock */
    clock = VBEGetPixelClock(pVbe, data->mode, data->block->PixelClock);
    if (clock)
	data->block->PixelClock = clock;

    data->mode |= (1 << 11);
    data->block->RefreshRate = 100 * ((double)(data->block->PixelClock) /
				(double)(ddcmode->HTotal * ddcmode->VTotal));
}

/*
 * Despite that VBE gives you pixel granularity for mode sizes, some BIOSes
 * think they can only give sizes in multiples of character cells; and
 * indeed, the reference CVT and GTF formulae only give results where
 * (h % 8) == 0.  Whatever, let's just try to cope.  What we're looking for
 * here is cases where the display says 1366x768 and the BIOS says 1360x768.
 */
static Bool
vesaModesCloseEnough(DisplayModePtr edid, DisplayModePtr vbe)
{
    if (!(edid->type & M_T_DRIVER))
	return FALSE;

    /* never seen a height granularity... */
    if (edid->VDisplay != vbe->VDisplay)
	return FALSE;

    if (edid->HDisplay >= vbe->HDisplay &&
	(edid->HDisplay & ~7) == (vbe->HDisplay & ~7))
	return TRUE;

    return FALSE;
}

static ModeStatus
VESAValidMode(int scrn, DisplayModePtr p, Bool flag, int pass)
{
    static int warned = 0;
    int found = 0;
    ScrnInfoPtr pScrn = xf86Screens[scrn];
    VESAPtr pVesa = VESAGetRec(pScrn);
    MonPtr mon = pScrn->monitor;
    ModeStatus ret = MODE_BAD;
    DisplayModePtr mode;
    float v;

    pVesa = VESAGetRec(pScrn);

    if (pass != MODECHECK_FINAL) {
	if (!warned) {
	    xf86DrvMsg(scrn, X_WARNING, "VESAValidMode called unexpectedly\n");
	    warned = 1;
	}
	return MODE_OK;
    }

    /*
     * This is suboptimal.  We pass in just the barest description of a mode
     * we can get away with to VBEValidateModes, so it can't really throw
     * out anything we give it.  But we need to filter the list so that we
     * don't populate the mode list with things the monitor can't do.
     *
     * So first off, if this isn't a mode we handed to the server (ie,
     * M_T_BUILTIN), then we know we can't do it.
     */
    if (!(p->type & M_T_BUILTIN))
	return MODE_NOMODE;

    if (pVesa->strict_validation) {
	/*
	 * If it's our first pass at mode validation, we'll try for a strict
	 * intersection between the VBE and DDC mode lists.
	 */
	if (pScrn->monitor->DDC) {
	    for (mode = pScrn->monitor->Modes; mode; mode = mode->next) {
		if (vesaModesCloseEnough(mode, p)) {
		    if (xf86CheckModeForMonitor(mode, mon) == MODE_OK) {
			found = 1;
			break;
		    }
		}
		if (mode == pScrn->monitor->Last)
		    break;
	    }
	    if (!found)
		return MODE_NOMODE;

	    /* having found a matching mode, stash the CRTC values aside */
	    VESASetModeParameters(pVesa->pVbe, p, mode);
	    return MODE_OK;
	}

	/* No DDC and no modes make Homer something something... */
	return MODE_NOMODE;
    }

    /*
     * Finally, walk through the vsync rates 1Hz at a time looking for a mode
     * that will fit.  This is assuredly a terrible way to do this, but
     * there's no obvious method for computing a mode of a given size that
     * will pass xf86CheckModeForMonitor.  XXX this path is terrible, but
     * then, by this point, you're well into despair territory.
     */
    for (v = mon->vrefresh[0].lo; v <= mon->vrefresh[0].hi; v++) {
	mode = xf86GTFMode(p->HDisplay, p->VDisplay, v, 0, 0);
	ret = xf86CheckModeForMonitor(mode, mon);
	free(mode->name);
	free(mode);
	if (ret == MODE_OK)
	    break;
    }

    return ret;
}

static void
VESAInitScrn(ScrnInfoPtr pScrn)
{
    pScrn->driverVersion = VESA_VERSION;
    pScrn->driverName    = VESA_DRIVER_NAME;
    pScrn->name		 = VESA_NAME;
    pScrn->Probe	 = VESAProbe;
    pScrn->PreInit       = VESAPreInit;
    pScrn->ScreenInit    = VESAScreenInit;
    pScrn->SwitchMode    = VESASwitchMode;
    pScrn->ValidMode     = VESAValidMode;
    pScrn->AdjustFrame   = VESAAdjustFrame;
    pScrn->EnterVT       = VESAEnterVT;
    pScrn->LeaveVT       = VESALeaveVT;
    pScrn->FreeScreen    = VESAFreeScreen;
}

/*
 * This function is called once, at the start of the first server generation to
 * do a minimal probe for supported hardware.
 */

#ifdef XSERVER_LIBPCIACCESS
static Bool
VESAPciProbe(DriverPtr drv, int entity_num, struct pci_device *dev,
	     intptr_t match_data)
{
    ScrnInfoPtr pScrn;
    
    pScrn = xf86ConfigPciEntity(NULL, 0, entity_num, NULL, 
				NULL, NULL, NULL, NULL, NULL);
    if (pScrn != NULL) {
	VESAPtr pVesa;

	if (pci_device_has_kernel_driver(dev)) {
	    ErrorF("vesa: Ignoring device with a bound kernel driver\n");
	    return FALSE;
	}

	pVesa = VESAGetRec(pScrn);
	VESAInitScrn(pScrn);
	pVesa->pciInfo = dev;
    }

    return (pScrn != NULL);
}
#endif

static Bool
VESAProbe(DriverPtr drv, int flags)
{
    Bool foundScreen = FALSE;
    int numDevSections, numUsed;
    GDevPtr *devSections;
    int *usedChips;
    int i;

    /*
     * Find the config file Device sections that match this
     * driver, and return if there are none.
     */
    if ((numDevSections = xf86MatchDevice(VESA_NAME,
					  &devSections)) <= 0)
	return (FALSE);

#ifndef XSERVER_LIBPCIACCESS
    /* PCI BUS */
    if (xf86GetPciVideoInfo()) {
	numUsed = xf86MatchPciInstances(VESA_NAME, PCI_VENDOR_GENERIC,
					VESAChipsets, VESAPCIchipsets, 
					devSections, numDevSections,
					drv, &usedChips);
	if (numUsed > 0) {
	    if (flags & PROBE_DETECT)
		foundScreen = TRUE;
	    else {
		for (i = 0; i < numUsed; i++) {
		    ScrnInfoPtr pScrn = NULL;
		    /* Allocate a ScrnInfoRec  */
		    if ((pScrn = xf86ConfigPciEntity(pScrn,0,usedChips[i],
						     VESAPCIchipsets,NULL,
						     NULL,NULL,NULL,NULL))) {
			VESAInitScrn(pScrn);
			foundScreen = TRUE;
		    }
		}
	    }
	    free(usedChips);
	}
    }
#endif

#ifdef HAVE_ISA
    /* Isa Bus */
    numUsed = xf86MatchIsaInstances(VESA_NAME,VESAChipsets,
				    VESAISAchipsets, drv,
				    VESAFindIsaDevice, devSections,
				    numDevSections, &usedChips);
    if(numUsed > 0) {
	if (flags & PROBE_DETECT)
	    foundScreen = TRUE;
	else for (i = 0; i < numUsed; i++) {
	    ScrnInfoPtr pScrn = NULL;
	    if ((pScrn = xf86ConfigIsaEntity(pScrn, 0,usedChips[i],
					     VESAISAchipsets, NULL,
					     NULL, NULL, NULL, NULL))) {
		VESAInitScrn(pScrn);
		foundScreen = TRUE;
	    }
	}
	free(usedChips);
    }
#endif

    free(devSections);

    return (foundScreen);
}

#ifdef HAVE_ISA
static int
VESAFindIsaDevice(GDevPtr dev)
{
#ifndef PC98_EGC
    CARD16 GenericIOBase = VGAHW_GET_IOBASE();
    CARD8 CurrentValue, TestValue;

    /* There's no need to unlock VGA CRTC registers here */

    /* VGA has one more read/write attribute register than EGA */
    (void) inb(GenericIOBase + VGA_IN_STAT_1_OFFSET);  /* Reset flip-flop */
    outb(VGA_ATTR_INDEX, 0x14 | 0x20);
    CurrentValue = inb(VGA_ATTR_DATA_R);
    outb(VGA_ATTR_DATA_W, CurrentValue ^ 0x0F);
    outb(VGA_ATTR_INDEX, 0x14 | 0x20);
    TestValue = inb(VGA_ATTR_DATA_R);
    outb(VGA_ATTR_DATA_R, CurrentValue);

    /* Quit now if no VGA is present */
    if ((CurrentValue ^ 0x0F) != TestValue)
      return -1;
#endif
    return (int)CHIP_VESA_GENERIC;
}
#endif

static void
VESAFreeRec(ScrnInfoPtr pScrn)
{
    VESAPtr pVesa = VESAGetRec(pScrn);
#if 0
    DisplayModePtr mode = pScrn->modes;
    /* I am not sure if the modes will ever get freed.
     * Anyway, the data unknown to other modules is being freed here.
     */
    if (mode) {
	do {
	    if (mode->Private) {
		VbeModeInfoData *data = (VbeModeInfoData*)mode->Private;

		if (data->block)
		    free(data->block);

		free(data);

		mode->Private = NULL;
	    }
	    mode = mode->next;
	} while (mode && mode != pScrn->modes);
    }
#endif
    free(pVesa->monitor);
    free(pVesa->vbeInfo);
    free(pVesa->pal);
    free(pVesa->savedPal);
    free(pVesa->fonts);
    free(pScrn->driverPrivate);
    pScrn->driverPrivate = NULL;
}

static int
VESAValidateModes(ScrnInfoPtr pScrn)
{
    VESAPtr pVesa = VESAGetRec(pScrn);
    DisplayModePtr mode;

    for (mode = pScrn->monitor->Modes; mode; mode = mode->next)
	mode->status = MODE_OK;

    return VBEValidateModes(pScrn, NULL, pScrn->display->modes, 
			    NULL, NULL, 0, 32767, 1, 0, 32767,
			    pScrn->display->virtualX,
			    pScrn->display->virtualY,
			    pVesa->mapSize, LOOKUP_BEST_REFRESH);
}

/*
 * This function is called once for each screen at the start of the first
 * server generation to initialise the screen for all server generations.
 */
static Bool
VESAPreInit(ScrnInfoPtr pScrn, int flags)
{
    VESAPtr pVesa;
    VbeInfoBlock *vbe;
    DisplayModePtr pMode;
    VbeModeInfoBlock *mode;
    Gamma gzeros = {0.0, 0.0, 0.0};
    rgb rzeros = {0, 0, 0};
    pointer pDDCModule;
    int i;
    int flags24 = 0;
    int defaultDepth = 0;
    int defaultBpp = 0;
    int depths = 0;

    if (flags & PROBE_DETECT)
	return (FALSE);

    pVesa = VESAGetRec(pScrn);
    pVesa->pEnt = xf86GetEntityInfo(pScrn->entityList[0]);

    /* Load vbe module */
    if (!xf86LoadSubModule(pScrn, "vbe"))
        return (FALSE);

    if ((pVesa->pVbe = VBEExtendedInit(NULL, pVesa->pEnt->index,
				       SET_BIOS_SCRATCH
				       | RESTORE_BIOS_SCRATCH)) == NULL)
        return (FALSE);

#ifndef XSERVER_LIBPCIACCESS
    if (pVesa->pEnt->location.type == BUS_PCI) {
	pVesa->pciInfo = xf86GetPciInfoForEntity(pVesa->pEnt->index);
	pVesa->pciTag = pciTag(pVesa->pciInfo->bus, pVesa->pciInfo->device,
			       pVesa->pciInfo->func);
    }
#endif

    pScrn->chipset = "vesa";
    pScrn->monitor = pScrn->confScreen->monitor;
    pScrn->progClock = TRUE;
    pScrn->rgbBits = 8;

    if ((vbe = VBEGetVBEInfo(pVesa->pVbe)) == NULL)
	return (FALSE);
    pVesa->major = (unsigned)(vbe->VESAVersion >> 8);
    pVesa->minor = vbe->VESAVersion & 0xff;
    pVesa->vbeInfo = vbe;
    pScrn->videoRam = vbe->TotalMemory * 64;

    /*
     * Find what depths are available.
     */
    depths = VBEFindSupportedDepths(pVesa->pVbe, pVesa->vbeInfo, &flags24,
				    V_MODETYPE_VBE);

    /* Preferred order for default depth selection. */
    if (depths & V_DEPTH_24)
	defaultDepth = 24;
    else if (depths & V_DEPTH_16)
	defaultDepth = 16;
    else if (depths & V_DEPTH_15)
	defaultDepth = 15;
    else if (depths & V_DEPTH_8)
	defaultDepth = 8;
    else if (depths & V_DEPTH_4)
	defaultDepth = 4;
    else if (depths & V_DEPTH_1)
	defaultDepth = 1;

    if (defaultDepth == 24 && !(flags24 & Support32bppFb))
	defaultBpp = 24;

    /* Prefer 32bpp because 1999 called and wants its packed pixels back */
    if (flags24 & Support32bppFb)
	flags24 |= SupportConvert24to32 | PreferConvert24to32;
    if (flags24 & Support24bppFb)
	flags24 |= SupportConvert32to24;

    if (!xf86SetDepthBpp(pScrn, defaultDepth, 0, defaultBpp, flags24)) {
        vbeFree(pVesa->pVbe);
	return (FALSE);
    }
    xf86PrintDepthBpp(pScrn);

    /* color weight */
    if (pScrn->depth > 8 && !xf86SetWeight(pScrn, rzeros, rzeros)) {
        vbeFree(pVesa->pVbe);
	return (FALSE);
    }
    /* visual init */
    if (!xf86SetDefaultVisual(pScrn, -1)) {
        vbeFree(pVesa->pVbe);
	return (FALSE);
    }

    xf86SetGamma(pScrn, gzeros);

    if (pVesa->major >= 2) {
	/* Load ddc module */
	if ((pDDCModule = xf86LoadSubModule(pScrn, "ddc")) == NULL) {
	    vbeFree(pVesa->pVbe);
	    return (FALSE);
	}

	if ((pVesa->monitor = vbeDoEDID(pVesa->pVbe, pDDCModule)) != NULL) {
	    xf86PrintEDID(pVesa->monitor);
	}

	xf86UnloadSubModule(pDDCModule);
    }

    if ((pScrn->monitor->DDC = pVesa->monitor) != NULL)
	xf86SetDDCproperties(pScrn, pVesa->monitor);
#ifdef HAVE_PANELID
    else {
	void *panelid = VBEReadPanelID(pVesa->pVbe);
	VBEInterpretPanelID(pScrn->scrnIndex, panelid);
	free(panelid);
    }
#endif

    xf86DrvMsgVerb(pScrn->scrnIndex, X_INFO, DEBUG_VERB,
			"Searching for matching VESA mode(s):\n");

    /*
     * Check the available BIOS modes, and extract those that match the
     * requirements into the modePool.  Note: modePool is a NULL-terminated
     * list.
     */
    pScrn->modePool = VBEGetModePool (pScrn, pVesa->pVbe, pVesa->vbeInfo,
				      V_MODETYPE_VBE);

    xf86ErrorFVerb(DEBUG_VERB, "\n");
    xf86DrvMsgVerb(pScrn->scrnIndex, X_INFO, DEBUG_VERB,
		   "Total Memory: %d 64KB banks (%dkB)\n", vbe->TotalMemory,
		   (vbe->TotalMemory * 65536) / 1024);

    pVesa->mapSize = vbe->TotalMemory * 65536;
    if (pScrn->modePool == NULL) {
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "No matching modes\n");
        vbeFree(pVesa->pVbe);
	return (FALSE);
    }

    VBESetModeNames(pScrn->modePool);

    pVesa->strict_validation = TRUE;
    i = VESAValidateModes(pScrn);

    if (i <= 0) {
	xf86DrvMsg(pScrn->scrnIndex, X_WARNING,
		"No valid modes left. Trying less strict filter...\n");
	pVesa->strict_validation = FALSE;
	i = VESAValidateModes(pScrn);
    }

    if (i <= 0) do {
	Bool changed = FALSE;
	/* maybe there's more modes at the bottom... */
	if (pScrn->monitor->vrefresh[0].lo > 50) {
	    changed = TRUE;
	    pScrn->monitor->vrefresh[0].lo = 50;
	}
	if (pScrn->monitor->hsync[0].lo > 31.5) {
	    changed = TRUE;
	    pScrn->monitor->hsync[0].lo = 31.5;
	}

	if (!changed)
	    break;

	xf86DrvMsg(pScrn->scrnIndex, X_WARNING,
		   "No valid modes left. Trying aggressive sync range...\n");
	i = VESAValidateModes(pScrn);
    } while (0);	

    if (i <= 0) {
	/* alright, i'm out of ideas */
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "No valid modes\n");
        vbeFree(pVesa->pVbe);
	return (FALSE);
    }

    xf86PruneDriverModes(pScrn);

    pMode = pScrn->modes;
    do {
	mode = ((VbeModeInfoData*)pMode->Private)->data;
	if (mode->BytesPerScanline > pVesa->maxBytesPerScanline) {
	    pVesa->maxBytesPerScanline = mode->BytesPerScanline;
	}
	pMode = pMode->next;
    } while (pMode != pScrn->modes);

    pScrn->currentMode = pScrn->modes;
    pScrn->displayWidth = pScrn->virtualX;

    VBEPrintModes(pScrn);

    /* Set display resolution */
    xf86SetDpi(pScrn, 0, 0);

    if (pScrn->modes == NULL) {
	xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "No modes\n");
        vbeFree(pVesa->pVbe);
	return (FALSE);
    }

    /* options */
    xf86CollectOptions(pScrn, NULL);
    if (!(pVesa->Options = malloc(sizeof(VESAOptions)))) {
        vbeFree(pVesa->pVbe);
	return FALSE;
    }
    memcpy(pVesa->Options, VESAOptions, sizeof(VESAOptions));
    xf86ProcessOptions(pScrn->scrnIndex, pScrn->options, pVesa->Options);

    /* Use shadow by default */
    if (xf86ReturnOptValBool(pVesa->Options, OPTION_SHADOW_FB, TRUE)) 
	pVesa->shadowFB = TRUE;

    if (xf86ReturnOptValBool(pVesa->Options, OPTION_DFLT_REFRESH, FALSE))
	pVesa->defaultRefresh = TRUE;

    pVesa->ModeSetClearScreen = FALSE;
    if (xf86ReturnOptValBool(pVesa->Options, OPTION_MODESET_CLEAR_SCREEN, 
			     FALSE))
	pVesa->ModeSetClearScreen = TRUE;

    if (!pVesa->defaultRefresh && !pVesa->strict_validation)
	VBESetModeParameters(pScrn, pVesa->pVbe);

    mode = ((VbeModeInfoData*)pScrn->modes->Private)->data;
    switch (mode->MemoryModel) {
	case 0x4:	/* Packed pixel */
	case 0x6:	/* Direct Color */
	    pScrn->bitmapBitOrder = BITMAP_BIT_ORDER; 

	    switch (pScrn->bitsPerPixel) {
		case 8:
		case 16:
		case 24:
		case 32:
		    break;
		default:
		    xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
			       "Unsupported bpp: %d", pScrn->bitsPerPixel);
		    vbeFree(pVesa->pVbe);
		    return FALSE;
	    }
	    break;
	default:
	    xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
		       "Unsupported Memory Model: %d", mode->MemoryModel);
	    return FALSE;
    }

    if (pVesa->shadowFB) {
	xf86DrvMsg(pScrn->scrnIndex, X_CONFIG, "Using \"Shadow Framebuffer\"\n");
	if (!xf86LoadSubModule(pScrn, "shadow")) {
	    vbeFree(pVesa->pVbe);
	    return (FALSE);
	}
    }

    if (xf86LoadSubModule(pScrn, "fb") == NULL) {
	VESAFreeRec(pScrn);
        vbeFree(pVesa->pVbe);
	return (FALSE);
    }

    vbeFree(pVesa->pVbe);

    return (TRUE);
}

static Bool
vesaCreateScreenResources(ScreenPtr pScreen)
{
    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
    VESAPtr pVesa = VESAGetRec(pScrn);
    Bool ret;

    pScreen->CreateScreenResources = pVesa->CreateScreenResources;
    ret = pScreen->CreateScreenResources(pScreen);
    pScreen->CreateScreenResources = vesaCreateScreenResources;

    shadowAdd(pScreen, pScreen->GetScreenPixmap(pScreen), pVesa->update,
	      pVesa->window, 0, 0);

    return ret;
}

static void
vesaEnableDisableFBAccess(int scrnIndex, Bool enable)
{
    ScrnInfoPtr pScrn = xf86Screens[scrnIndex];
    VESAPtr pVesa = VESAGetRec(pScrn);

    pVesa->accessEnabled = enable;
    pVesa->EnableDisableFBAccess(scrnIndex, enable);
}

static Bool
VESAScreenInit(int scrnIndex, ScreenPtr pScreen, int argc, char **argv)
{
    ScrnInfoPtr pScrn = xf86Screens[scrnIndex];
    VESAPtr pVesa = VESAGetRec(pScrn);
    VisualPtr visual;
    VbeModeInfoBlock *mode;
    int flags;

    if ((pVesa->pVbe = VBEExtendedInit(NULL, pVesa->pEnt->index,
				       SET_BIOS_SCRATCH
				       | RESTORE_BIOS_SCRATCH)) == NULL)
        return (FALSE);

    if (pVesa->mapPhys == 0) {
	mode = ((VbeModeInfoData*)(pScrn->currentMode->Private))->data;
	pScrn->videoRam = pVesa->mapSize;
	pVesa->mapPhys = mode->PhysBasePtr;
	pVesa->mapOff = 0;
    }

    if (pVesa->mapPhys == 0) {
	pVesa->mapPhys = 0xa0000;
	pVesa->mapSize = 0x10000;
    }

    if (!VESAMapVidMem(pScrn)) {
	if (pVesa->mapPhys != 0xa0000) {
	    pVesa->mapPhys = 0xa0000;
	    pVesa->mapSize = 0x10000;
	    if (!VESAMapVidMem(pScrn))
		return (FALSE);
	}
	else
	    return (FALSE);
    }

    /* Set bpp to 8 for depth 4 when using shadowfb. */
    if (pVesa->shadowFB && pScrn->bitsPerPixel == 4)
	pScrn->bitsPerPixel = 8;

    if (pVesa->shadowFB) {
	pVesa->shadow = calloc(1, pScrn->displayWidth * pScrn->virtualY *
				   ((pScrn->bitsPerPixel + 7) / 8));
	if (!pVesa->shadow) {
	    xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
		       "Failed to allocate shadow buffer\n");
	    return FALSE;
	}
    }

    /* save current video state */
    VESASaveRestore(pScrn, MODE_SAVE);
    pVesa->savedPal = VBESetGetPaletteData(pVesa->pVbe, FALSE, 0, 256,
					    NULL, FALSE, FALSE);

    /* set first video mode */
    if (!VESASetMode(pScrn, pScrn->currentMode))
	return (FALSE);

    /* set the viewport */
    VESAAdjustFrame(scrnIndex, pScrn->frameX0, pScrn->frameY0, 0);

    /* Blank the screen for aesthetic reasons. */
    VESASaveScreen(pScreen, SCREEN_SAVER_ON);

    /* mi layer */
    miClearVisualTypes();
    if (!xf86SetDefaultVisual(pScrn, -1))
	return (FALSE);
    if (pScrn->bitsPerPixel > 8) {
	if (!miSetVisualTypes(pScrn->depth, TrueColorMask,
			      pScrn->rgbBits, TrueColor))
	    return (FALSE);
    }
    else {
	if (!miSetVisualTypes(pScrn->depth,
			      miGetDefaultVisualMask(pScrn->depth),
			      pScrn->rgbBits, pScrn->defaultVisual))
	    return (FALSE);
    }
    if (!miSetPixmapDepths())
	return (FALSE);

    mode = ((VbeModeInfoData*)pScrn->modes->Private)->data;
    switch (mode->MemoryModel) {
	case 0x4:	/* Packed pixel */
	case 0x6:	/* Direct Color */
	    switch (pScrn->bitsPerPixel) {
		case 8:
		case 16:
		case 24:
		case 32:
		    if (!fbScreenInit(pScreen,
				pVesa->shadowFB ? pVesa->shadow : pVesa->base,
				       pScrn->virtualX, pScrn->virtualY,
				       pScrn->xDpi, pScrn->yDpi,
				       pScrn->displayWidth, pScrn->bitsPerPixel))
			return (FALSE);
		    break;
		default:
		    xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
			       "Unsupported bpp: %d", pScrn->bitsPerPixel);
		    return (FALSE);
	    }
	    break;
	default:
	    xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
		       "Unsupported Memory Model: %d", mode->MemoryModel);
	    return (FALSE);
    }


    if (pScrn->bitsPerPixel > 8) {
	/* Fixup RGB ordering */
	visual = pScreen->visuals + pScreen->numVisuals;
	while (--visual >= pScreen->visuals) {
	    if ((visual->class | DynamicClass) == DirectColor) {
		visual->offsetRed   = pScrn->offset.red;
		visual->offsetGreen = pScrn->offset.green;
		visual->offsetBlue  = pScrn->offset.blue;
		visual->redMask     = pScrn->mask.red;
		visual->greenMask   = pScrn->mask.green;
		visual->blueMask    = pScrn->mask.blue;
	    }
	}
    }

    /* must be after RGB ordering fixed */
    fbPictureInit(pScreen, 0, 0);

    if (pVesa->shadowFB) {
	if (pVesa->mapPhys == 0xa0000) {	/* Windowed */
	    pVesa->update = vesaUpdatePacked;
	    pVesa->window = VESAWindowWindowed;
	}
	else {	/* Linear */
	    pVesa->update = vesaUpdatePacked;
	    pVesa->window = VESAWindowLinear;
	}

	if (!shadowSetup(pScreen))
	    return FALSE;
	pVesa->CreateScreenResources = pScreen->CreateScreenResources;
	pScreen->CreateScreenResources = vesaCreateScreenResources;
    }
    else if (pVesa->mapPhys == 0xa0000) {
        xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
                   "Banked framebuffer requires ShadowFB\n");
        return FALSE;
    }

    VESADGAInit(pScrn, pScreen);

    xf86SetBlackWhitePixels(pScreen);
    miInitializeBackingStore(pScreen);
    xf86SetBackingStore(pScreen);

    /* software cursor */
    miDCInitialize(pScreen, xf86GetPointerScreenFuncs());

    /* colormap */
    if (!miCreateDefColormap(pScreen))
	return (FALSE);

    flags = CMAP_RELOAD_ON_MODE_SWITCH;

    if(!xf86HandleColormaps(pScreen, 256,
	pVesa->vbeInfo->Capabilities[0] & 0x01 ? 8 : 6,
	VESALoadPalette, NULL, flags))
	return (FALSE);

    pVesa->accessEnabled = TRUE;
    pVesa->EnableDisableFBAccess = pScrn->EnableDisableFBAccess;
    pScrn->EnableDisableFBAccess = vesaEnableDisableFBAccess;

    pVesa->CloseScreen = pScreen->CloseScreen;
    pScreen->CloseScreen = VESACloseScreen;
    pScreen->SaveScreen = VESASaveScreen;

    xf86DPMSInit(pScreen, VESADisplayPowerManagementSet, 0);

    /* Report any unused options (only for the first generation) */
    if (serverGeneration == 1)
        xf86ShowUnusedOptions(pScrn->scrnIndex, pScrn->options);

    return (TRUE);
}

static Bool
VESAEnterVT(int scrnIndex, int flags)
{
    ScrnInfoPtr pScrn = xf86Screens[scrnIndex];

    if (!VESASetMode(pScrn, pScrn->currentMode))
	return FALSE;
    VESAAdjustFrame(scrnIndex, pScrn->frameX0, pScrn->frameY0, 0);
    return TRUE;
}

static void
VESALeaveVT(int scrnIndex, int flags)
{
    VESASaveRestore(xf86Screens[scrnIndex], MODE_RESTORE);
}

static Bool
VESACloseScreen(int scrnIndex, ScreenPtr pScreen)
{
    ScrnInfoPtr pScrn = xf86Screens[scrnIndex];
    VESAPtr pVesa = VESAGetRec(pScrn);

    if (pScrn->vtSema) {
	VESASaveRestore(xf86Screens[scrnIndex], MODE_RESTORE);
	if (pVesa->savedPal)
	    VBESetGetPaletteData(pVesa->pVbe, TRUE, 0, 256,
				 pVesa->savedPal, FALSE, TRUE);
	VESAUnmapVidMem(pScrn);
    }
    if (pVesa->shadowFB && pVesa->shadow) {
	shadowRemove(pScreen, pScreen->GetScreenPixmap(pScreen));
	free(pVesa->shadow);
    }
    if (pVesa->pDGAMode) {
	free(pVesa->pDGAMode);
	pVesa->pDGAMode = NULL;
	pVesa->nDGAMode = 0;
    }
    pScrn->vtSema = FALSE;

    pScrn->EnableDisableFBAccess = pVesa->EnableDisableFBAccess;
    pScreen->CreateScreenResources = pVesa->CreateScreenResources;
    pScreen->CloseScreen = pVesa->CloseScreen;
    return pScreen->CloseScreen(scrnIndex, pScreen);
}

static Bool
VESASwitchMode(int scrnIndex, DisplayModePtr pMode, int flags)
{
    ScrnInfoPtr pScrn = xf86Screens[scrnIndex];
    VESAPtr pVesa = VESAGetRec(pScrn);
    Bool ret, disableAccess = pVesa->ModeSetClearScreen && pVesa->accessEnabled;

    if (disableAccess)
	pScrn->EnableDisableFBAccess(scrnIndex,FALSE);
    ret = VESASetMode(xf86Screens[scrnIndex], pMode);
    if (disableAccess)
	pScrn->EnableDisableFBAccess(scrnIndex,TRUE);
    return ret;
}

/* Set a graphics mode */
static Bool
VESASetMode(ScrnInfoPtr pScrn, DisplayModePtr pMode)
{
    VESAPtr pVesa;
    VbeModeInfoData *data;
    int mode;

    pVesa = VESAGetRec(pScrn);

    data = (VbeModeInfoData*)pMode->Private;

    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
	       "Setting up VESA Mode 0x%X (%dx%d)\n",
	       data->mode & 0x7FF, pMode->HDisplay, pMode->VDisplay);

    /* careful, setting the bit means don't clear the screen */
    mode = data->mode | (pVesa->ModeSetClearScreen ? 0 : (1U << 15));

    /* enable linear addressing */
    if (pVesa->mapPhys != 0xa0000)
	mode |= 1 << 14;

    if (VBESetVBEMode(pVesa->pVbe, mode, data->block) == FALSE) {
	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "VBESetVBEMode failed");
	if ((data->block || (data->mode & (1 << 11))) &&
	    VBESetVBEMode(pVesa->pVbe, (mode & ~(1 << 11)), NULL) == TRUE) {
	    /* Some cards do not like setting the clock.
	     * Free it as it will not be any longer useful
	     */
	    xf86ErrorF(", mode set without customized refresh.\n");
	    free(data->block);
	    data->block = NULL;
	    data->mode &= ~(1 << 11);
	}
	else {
	    ErrorF("\n");
	    return (FALSE);
	}
    }

    pVesa->bankSwitchWindowB =
	!((data->data->WinBSegment == 0) && (data->data->WinBAttributes == 0));

    if (data->data->XResolution != pScrn->displayWidth)
	VBESetLogicalScanline(pVesa->pVbe, pScrn->displayWidth);

    if (pScrn->bitsPerPixel == 8 && pVesa->vbeInfo->Capabilities[0] & 0x01 &&
        !(data->data->MemoryModel == 0x6 || data->data->MemoryModel == 0x7)) 
	VBESetGetDACPaletteFormat(pVesa->pVbe, 8);

    pScrn->vtSema = TRUE;

    return (TRUE);
}

static void
VESAAdjustFrame(int scrnIndex, int x, int y, int flags)
{
    VESAPtr pVesa = VESAGetRec(xf86Screens[scrnIndex]);

    VBESetDisplayStart(pVesa->pVbe, x, y, TRUE);
}

static void
VESAFreeScreen(int scrnIndex, int flags)
{
    VESAFreeRec(xf86Screens[scrnIndex]);
}

static Bool
VESAMapVidMem(ScrnInfoPtr pScrn)
{
    VESAPtr pVesa = VESAGetRec(pScrn);

    if (pVesa->base != NULL)
	return (TRUE);

    pScrn->memPhysBase = pVesa->mapPhys;
    pScrn->fbOffset = pVesa->mapOff;

#ifdef XSERVER_LIBPCIACCESS
    if ((pVesa->mapPhys != 0xa0000) && (pVesa->pciInfo != NULL)) {
	(void) pci_device_map_range(pVesa->pciInfo, pScrn->memPhysBase,
				    pVesa->mapSize,
				    (PCI_DEV_MAP_FLAG_WRITABLE
				     | PCI_DEV_MAP_FLAG_WRITE_COMBINE),
				    & pVesa->base);
    }
    else
	(void) pci_device_map_legacy(pVesa->pciInfo, pScrn->memPhysBase,
	                             pVesa->mapSize,
	                             PCI_DEV_MAP_FLAG_WRITABLE,
	                             & pVesa->base);

    if (pVesa->base) {
	if (pVesa->mapPhys != 0xa0000)
	    (void) pci_device_map_legacy(pVesa->pciInfo, 0xa0000, 0x10000,
	                                 PCI_DEV_MAP_FLAG_WRITABLE,
	                                 & pVesa->VGAbase);
	else
	    pVesa->VGAbase = pVesa->base;

    }
#else
    if (pVesa->mapPhys != 0xa0000 && pVesa->pEnt->location.type == BUS_PCI)
	pVesa->base = xf86MapPciMem(pScrn->scrnIndex, VIDMEM_FRAMEBUFFER,
				    pVesa->pciTag, pScrn->memPhysBase,
				    pVesa->mapSize);
    else
	pVesa->base = xf86MapDomainMemory(pScrn->scrnIndex, 0, pVesa->pciTag,
					  pScrn->memPhysBase, pVesa->mapSize);

    if (pVesa->base) {
	if (pVesa->mapPhys != 0xa0000)
	    pVesa->VGAbase = xf86MapDomainMemory(pScrn->scrnIndex, 0,
						 pVesa->pciTag,
						 0xa0000, 0x10000);
	else
	    pVesa->VGAbase = pVesa->base;
    }
#endif

#if GET_ABI_MAJOR(ABI_VIDEODRV_VERSION) < 12
    pVesa->ioBase = pScrn->domainIOBase;
#else
    pVesa->ioBase = 0;
#endif

    xf86DrvMsgVerb(pScrn->scrnIndex, X_INFO, DEBUG_VERB,
		   "virtual address = %p,\n"
		   "\tphysical address = 0x%lx, size = %ld\n",
		   pVesa->base, pScrn->memPhysBase, pVesa->mapSize);

    return (pVesa->base != NULL);
}

static void
VESAUnmapVidMem(ScrnInfoPtr pScrn)
{
    VESAPtr pVesa = VESAGetRec(pScrn);

    if (pVesa->base == NULL)
	return;

#ifdef XSERVER_LIBPCIACCESS
    if (pVesa->mapPhys != 0xa0000) {
	(void) pci_device_unmap_range(pVesa->pciInfo, pVesa->base,
				      pVesa->mapSize);
	(void) pci_device_unmap_legacy(pVesa->pciInfo, pVesa->VGAbase,
	                               0x10000);
    }
    else {
	(void) pci_device_unmap_legacy(pVesa->pciInfo, pVesa->base,
	                               pVesa->mapSize);
    }
#else
    xf86UnMapVidMem(pScrn->scrnIndex, pVesa->base, pVesa->mapSize);
    if (pVesa->mapPhys != 0xa0000)
	xf86UnMapVidMem(pScrn->scrnIndex, pVesa->VGAbase, 0x10000);
#endif
    pVesa->base = NULL;
}

/* This code works, but is very slow for programs that use it intensively */
static void
VESALoadPalette(ScrnInfoPtr pScrn, int numColors, int *indices,
		LOCO *colors, VisualPtr pVisual)
{
    VESAPtr pVesa = VESAGetRec(pScrn);
    int i, idx;
    int base;

    if (pVesa->pal == NULL)
	pVesa->pal = calloc(1, sizeof(CARD32) * 256);

    for (i = 0, base = idx = indices[i]; i < numColors; i++, idx++) {
	int j = indices[i];

	if (j < 0 || j >= 256)
	    continue;
	pVesa->pal[j] = colors[j].blue |
			(colors[j].green << 8) |
			(colors[j].red << 16);
	if (j != idx) {
	    VBESetGetPaletteData(pVesa->pVbe, TRUE, base, idx - base,
				  pVesa->pal + base, FALSE, TRUE);
	    idx = base = j;
	}
    }

    if (idx - 1 == indices[i - 1])
	VBESetGetPaletteData(pVesa->pVbe, TRUE, base, idx - base,
			      pVesa->pal + base, FALSE, TRUE);
}

/*
 * Just adapted from the std* functions in vgaHW.c
 */
static void
WriteAttr(VESAPtr pVesa, int index, int value)
{
    (void) inb(pVesa->ioBase + VGA_IOBASE_COLOR + VGA_IN_STAT_1_OFFSET);

    index |= 0x20;
    outb(pVesa->ioBase + VGA_ATTR_INDEX, index);
    outb(pVesa->ioBase + VGA_ATTR_DATA_W, value);
}

static int
ReadAttr(VESAPtr pVesa, int index)
{
    (void) inb(pVesa->ioBase + VGA_IOBASE_COLOR + VGA_IN_STAT_1_OFFSET);

    index |= 0x20;
    outb(pVesa->ioBase + VGA_ATTR_INDEX, index);
    return (inb(pVesa->ioBase + VGA_ATTR_DATA_R));
}

#define WriteMiscOut(value)	outb(pVesa->ioBase + VGA_MISC_OUT_W, value)
#define ReadMiscOut()		inb(pVesa->ioBase + VGA_MISC_OUT_R)
#define WriteSeq(index, value)	outb(pVesa->ioBase + VGA_SEQ_INDEX, index);\
				outb(pVesa->ioBase + VGA_SEQ_DATA, value)

static int
ReadSeq(VESAPtr pVesa, int index)
{
    outb(pVesa->ioBase + VGA_SEQ_INDEX, index);

    return (inb(pVesa->ioBase + VGA_SEQ_DATA));
}

#define WriteGr(index, value)				\
    outb(pVesa->ioBase + VGA_GRAPH_INDEX, index);	\
    outb(pVesa->ioBase + VGA_GRAPH_DATA, value)

static int
ReadGr(VESAPtr pVesa, int index)
{
    outb(pVesa->ioBase + VGA_GRAPH_INDEX, index);

    return (inb(pVesa->ioBase + VGA_GRAPH_DATA));
}

#define WriteCrtc(index, value)						     \
    outb(pVesa->ioBase + (VGA_IOBASE_COLOR + VGA_CRTC_INDEX_OFFSET), index); \
    outb(pVesa->ioBase + (VGA_IOBASE_COLOR + VGA_CRTC_DATA_OFFSET), value)

static void
SeqReset(VESAPtr pVesa, Bool start)
{
    if (start) {
	WriteSeq(0x00, 0x01);		/* Synchronous Reset */
    }
    else {
	WriteSeq(0x00, 0x03);		/* End Reset */
    }
}

static void
SaveFonts(ScrnInfoPtr pScrn)
{
    VESAPtr pVesa = VESAGetRec(pScrn);
    unsigned char miscOut, attr10, gr4, gr5, gr6, seq2, seq4, scrn;

    if (pVesa->fonts != NULL)
	return;

    /* If in graphics mode, don't save anything */
    attr10 = ReadAttr(pVesa, 0x10);
    if (attr10 & 0x01)
	return;

    pVesa->fonts = malloc(16384);

    /* save the registers that are needed here */
    miscOut = ReadMiscOut();
    gr4 = ReadGr(pVesa, 0x04);
    gr5 = ReadGr(pVesa, 0x05);
    gr6 = ReadGr(pVesa, 0x06);
    seq2 = ReadSeq(pVesa, 0x02);
    seq4 = ReadSeq(pVesa, 0x04);

    /* Force into colour mode */
    WriteMiscOut(miscOut | 0x01);

    scrn = ReadSeq(pVesa, 0x01) | 0x20;
    SeqReset(pVesa, TRUE);
    WriteSeq(0x01, scrn);
    SeqReset(pVesa, FALSE);

    WriteAttr(pVesa, 0x10, 0x01);	/* graphics mode */

    /*font1 */
    WriteSeq(0x02, 0x04);	/* write to plane 2 */
    WriteSeq(0x04, 0x06);	/* enable plane graphics */
    WriteGr(0x04, 0x02);	/* read plane 2 */
    WriteGr(0x05, 0x00);	/* write mode 0, read mode 0 */
    WriteGr(0x06, 0x05);	/* set graphics */
    slowbcopy_frombus(pVesa->VGAbase, pVesa->fonts, 8192);

    /* font2 */
    WriteSeq(0x02, 0x08);	/* write to plane 3 */
    WriteSeq(0x04, 0x06);	/* enable plane graphics */
    WriteGr(0x04, 0x03);	/* read plane 3 */
    WriteGr(0x05, 0x00);	/* write mode 0, read mode 0 */
    WriteGr(0x06, 0x05);	/* set graphics */
    slowbcopy_frombus(pVesa->VGAbase, pVesa->fonts + 8192, 8192);

    scrn = ReadSeq(pVesa, 0x01) & ~0x20;
    SeqReset(pVesa, TRUE);
    WriteSeq(0x01, scrn);
    SeqReset(pVesa, FALSE);

    /* Restore clobbered registers */
    WriteAttr(pVesa, 0x10, attr10);
    WriteSeq(0x02, seq2);
    WriteSeq(0x04, seq4);
    WriteGr(0x04, gr4);
    WriteGr(0x05, gr5);
    WriteGr(0x06, gr6);
    WriteMiscOut(miscOut);
}

static void
RestoreFonts(ScrnInfoPtr pScrn)
{
    VESAPtr pVesa = VESAGetRec(pScrn);
    unsigned char miscOut, attr10, gr1, gr3, gr4, gr5, gr6, gr8, seq2, seq4, scrn;

    if (pVesa->fonts == NULL)
	return;

    if (pVesa->mapPhys == 0xa0000 && pVesa->curBank != 0)
	VESABankSwitch(pScrn->pScreen, 0);

    /* save the registers that are needed here */
    miscOut = ReadMiscOut();
    attr10 = ReadAttr(pVesa, 0x10);
    gr1 = ReadGr(pVesa, 0x01);
    gr3 = ReadGr(pVesa, 0x03);
    gr4 = ReadGr(pVesa, 0x04);
    gr5 = ReadGr(pVesa, 0x05);
    gr6 = ReadGr(pVesa, 0x06);
    gr8 = ReadGr(pVesa, 0x08);
    seq2 = ReadSeq(pVesa, 0x02);
    seq4 = ReadSeq(pVesa, 0x04);

    /* Force into colour mode */
    WriteMiscOut(miscOut | 0x01);

    scrn = ReadSeq(pVesa, 0x01) | 0x20;
    SeqReset(pVesa, TRUE);
    WriteSeq(0x01, scrn);
    SeqReset(pVesa, FALSE);

    WriteAttr(pVesa, 0x10, 0x01);	/* graphics mode */
    if (pScrn->depth == 4) {
	/* GJA */
	WriteGr(0x03, 0x00);	/* don't rotate, write unmodified */
	WriteGr(0x08, 0xFF);	/* write all bits in a byte */
	WriteGr(0x01, 0x00);	/* all planes come from CPU */
    }

    WriteSeq(0x02, 0x04);   /* write to plane 2 */
    WriteSeq(0x04, 0x06);   /* enable plane graphics */
    WriteGr(0x04, 0x02);    /* read plane 2 */
    WriteGr(0x05, 0x00);    /* write mode 0, read mode 0 */
    WriteGr(0x06, 0x05);    /* set graphics */
    slowbcopy_tobus(pVesa->fonts, pVesa->VGAbase, 8192);

    WriteSeq(0x02, 0x08);   /* write to plane 3 */
    WriteSeq(0x04, 0x06);   /* enable plane graphics */
    WriteGr(0x04, 0x03);    /* read plane 3 */
    WriteGr(0x05, 0x00);    /* write mode 0, read mode 0 */
    WriteGr(0x06, 0x05);    /* set graphics */
    slowbcopy_tobus(pVesa->fonts + 8192, pVesa->VGAbase, 8192);

    scrn = ReadSeq(pVesa, 0x01) & ~0x20;
    SeqReset(pVesa, TRUE);
    WriteSeq(0x01, scrn);
    SeqReset(pVesa, FALSE);

    /* restore the registers that were changed */
    WriteMiscOut(miscOut);
    WriteAttr(pVesa, 0x10, attr10);
    WriteGr(0x01, gr1);
    WriteGr(0x03, gr3);
    WriteGr(0x04, gr4);
    WriteGr(0x05, gr5);
    WriteGr(0x06, gr6);
    WriteGr(0x08, gr8);
    WriteSeq(0x02, seq2);
    WriteSeq(0x04, seq4);
}

static Bool
VESASaveScreen(ScreenPtr pScreen, int mode)
{
    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
    VESAPtr pVesa = VESAGetRec(pScrn);
    Bool on = xf86IsUnblank(mode);

    if (on)
	SetTimeSinceLastInputEvent();

    if (pScrn->vtSema) {
	unsigned char scrn = ReadSeq(pVesa, 0x01);

	if (on)
	    scrn &= ~0x20;
	else
	    scrn |= 0x20;
	SeqReset(pVesa, TRUE);
	WriteSeq(0x01, scrn);
	SeqReset(pVesa, FALSE);
    }

    return (TRUE);
}

static int 
VESABankSwitch(ScreenPtr pScreen, unsigned int iBank)
{
    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
    VESAPtr pVesa = VESAGetRec(pScrn);

    if (pVesa->curBank == iBank)
	return (0);
    if (!VBEBankSwitch(pVesa->pVbe, iBank, 0))
        return (1);
    if (pVesa->bankSwitchWindowB) {
        if (!VBEBankSwitch(pVesa->pVbe, iBank, 1))
	   return (1);
    }
    pVesa->curBank = iBank;

    return (0);
}

Bool
VESASaveRestore(ScrnInfoPtr pScrn, vbeSaveRestoreFunction function)
{
    VESAPtr pVesa;

    if (MODE_QUERY < 0 || function > MODE_RESTORE)
	return (FALSE);

    pVesa = VESAGetRec(pScrn);


    /* Query amount of memory to save state */
    if (function == MODE_QUERY ||
	(function == MODE_SAVE && pVesa->state == NULL)) {

	/* Make sure we save at least this information in case of failure */
	(void)VBEGetVBEMode(pVesa->pVbe, &pVesa->stateMode);
	SaveFonts(pScrn);

	if (pVesa->major > 1) {
	    if (!VBESaveRestore(pVesa->pVbe,function,(pointer)&pVesa->state,
				&pVesa->stateSize,&pVesa->statePage))
	        return FALSE;

	}
    }

    /* Save/Restore Super VGA state */
    if (function != MODE_QUERY) {
        Bool retval = TRUE;

	if (pVesa->major > 1) {
	    if (function == MODE_RESTORE)
		memcpy(pVesa->state, pVesa->pstate, pVesa->stateSize);

	    if ((retval = VBESaveRestore(pVesa->pVbe,function,
					 (pointer)&pVesa->state,
					 &pVesa->stateSize,&pVesa->statePage))
		&& function == MODE_SAVE) {
	        /* don't rely on the memory not being touched */
	        if (pVesa->pstate == NULL)
		    pVesa->pstate = malloc(pVesa->stateSize);
		memcpy(pVesa->pstate, pVesa->state, pVesa->stateSize);
	    }
	}

	if (function == MODE_RESTORE) {
	    VBESetVBEMode(pVesa->pVbe, pVesa->stateMode, NULL);
	    RestoreFonts(pScrn);
	}

	if (!retval)
	    return (FALSE);

    }

    return (TRUE);
}

static void
VESADisplayPowerManagementSet(ScrnInfoPtr pScrn, int mode,
                int flags)
{
    VESAPtr pVesa = VESAGetRec(pScrn);

    if (!pScrn->vtSema)
	return;

    VBEDPMSSet(pVesa->pVbe, mode);
}

/***********************************************************************
 * DGA stuff
 ***********************************************************************/
static Bool VESADGAOpenFramebuffer(ScrnInfoPtr pScrn, char **DeviceName,
				   unsigned char **ApertureBase,
				   int *ApertureSize, int *ApertureOffset,
				   int *flags);
static Bool VESADGASetMode(ScrnInfoPtr pScrn, DGAModePtr pDGAMode);
static void VESADGASetViewport(ScrnInfoPtr pScrn, int x, int y, int flags);

static Bool
VESADGAOpenFramebuffer(ScrnInfoPtr pScrn, char **DeviceName,
		       unsigned char **ApertureBase, int *ApertureSize,
		       int *ApertureOffset, int *flags)
{
    VESAPtr pVesa = VESAGetRec(pScrn);

    *DeviceName = NULL;		/* No special device */
    *ApertureBase = (unsigned char *)(long)(pVesa->mapPhys);
    *ApertureSize = pVesa->mapSize;
    *ApertureOffset = pVesa->mapOff;
    *flags = DGA_NEED_ROOT;

    return (TRUE);
}

static Bool
VESADGASetMode(ScrnInfoPtr pScrn, DGAModePtr pDGAMode)
{
    DisplayModePtr pMode;
    int scrnIdx = pScrn->pScreen->myNum;
    int frameX0, frameY0;

    if (pDGAMode) {
	pMode = pDGAMode->mode;
	frameX0 = frameY0 = 0;
    }
    else {
	if (!(pMode = pScrn->currentMode))
	    return (TRUE);

	frameX0 = pScrn->frameX0;
	frameY0 = pScrn->frameY0;
    }

    if (!(*pScrn->SwitchMode)(scrnIdx, pMode, 0))
	return (FALSE);
    (*pScrn->AdjustFrame)(scrnIdx, frameX0, frameY0, 0);

    return (TRUE);
}

static void
VESADGASetViewport(ScrnInfoPtr pScrn, int x, int y, int flags)
{
    (*pScrn->AdjustFrame)(pScrn->pScreen->myNum, x, y, flags);
}

static int
VESADGAGetViewport(ScrnInfoPtr pScrn)
{
    return (0);
}

static DGAFunctionRec VESADGAFunctions =
{
    VESADGAOpenFramebuffer,
    NULL,       /* CloseFramebuffer */
    VESADGASetMode,
    VESADGASetViewport,
    VESADGAGetViewport,
    NULL,       /* Sync */
    NULL,       /* FillRect */
    NULL,       /* BlitRect */
    NULL,       /* BlitTransRect */
};

static void
VESADGAAddModes(ScrnInfoPtr pScrn)
{
    VESAPtr pVesa = VESAGetRec(pScrn);
    DisplayModePtr pMode = pScrn->modes;
    DGAModePtr pDGAMode;

    do {
	pDGAMode = realloc(pVesa->pDGAMode,
			    (pVesa->nDGAMode + 1) * sizeof(DGAModeRec));
	if (!pDGAMode)
	    break;

	pVesa->pDGAMode = pDGAMode;
	pDGAMode += pVesa->nDGAMode;
	(void)memset(pDGAMode, 0, sizeof(DGAModeRec));

	++pVesa->nDGAMode;
	pDGAMode->mode = pMode;
	pDGAMode->flags = DGA_CONCURRENT_ACCESS | DGA_PIXMAP_AVAILABLE;
	pDGAMode->byteOrder = pScrn->imageByteOrder;
	pDGAMode->depth = pScrn->depth;
	pDGAMode->bitsPerPixel = pScrn->bitsPerPixel;
	pDGAMode->red_mask = pScrn->mask.red;
	pDGAMode->green_mask = pScrn->mask.green;
	pDGAMode->blue_mask = pScrn->mask.blue;
	pDGAMode->visualClass = pScrn->bitsPerPixel > 8 ?
	    TrueColor : PseudoColor;
	pDGAMode->xViewportStep = 1;
	pDGAMode->yViewportStep = 1;
	pDGAMode->viewportWidth = pMode->HDisplay;
	pDGAMode->viewportHeight = pMode->VDisplay;

	pDGAMode->bytesPerScanline = pVesa->maxBytesPerScanline;
	pDGAMode->imageWidth = pMode->HDisplay;
	pDGAMode->imageHeight =  pMode->VDisplay;
	pDGAMode->pixmapWidth = pDGAMode->imageWidth;
	pDGAMode->pixmapHeight = pDGAMode->imageHeight;
	pDGAMode->maxViewportX = pScrn->virtualX -
				    pDGAMode->viewportWidth;
	pDGAMode->maxViewportY = pScrn->virtualY -
				    pDGAMode->viewportHeight;

	pDGAMode->address = pVesa->base;

	pMode = pMode->next;
    } while (pMode != pScrn->modes);
}

static Bool
VESADGAInit(ScrnInfoPtr pScrn, ScreenPtr pScreen)
{
    VESAPtr pVesa = VESAGetRec(pScrn);

    if (pScrn->depth < 8 || pVesa->mapPhys == 0xa0000L)
	return (FALSE);

    if (!pVesa->nDGAMode)
	VESADGAAddModes(pScrn);

    return (DGAInit(pScreen, &VESADGAFunctions,
	    pVesa->pDGAMode, pVesa->nDGAMode));
}