3 * Copyright (C) 1998, 1999, 2000, 2001, 2002 ReactOS Team
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
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10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 * COPYRIGHT: See COPYING in the top level directory
22 * PROJECT: ReactOS kernel
23 * FILE: ntoskrnl/hal/x86/display.c
24 * PURPOSE: Blue screen display
25 * PROGRAMMER: Eric Kohl (ekohl@rz-online.de)
31 * Portions of this code are from the XFree86 Project and available from the
34 * Copyright (C) 1994-2003 The XFree86 Project, Inc. All Rights Reserved.
36 * Permission is hereby granted, free of charge, to any person obtaining a copy
37 * of this software and associated documentation files (the "Software"), to
38 * deal in the Software without restriction, including without limitation the
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40 * sell copies of the Software, and to permit persons to whom the Software is
41 * furnished to do so, subject to the following conditions:
43 * The above copyright notice and this permission notice shall be included in
44 * all copies or substantial portions of the Software.
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51 * NECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
53 * Except as contained in this notice, the name of the XFree86 Project shall
54 * not be used in advertising or otherwise to promote the sale, use or other
55 * dealings in this Software without prior written authorization from the
61 * So, who owns the physical display and is allowed to write to it?
63 * In MS NT, upon boot HAL owns the display. Somewhere in the boot
64 * sequence (haven't figured out exactly where or by who), some
65 * component calls HalAcquireDisplayOwnership. From that moment on,
66 * the display is owned by that component and is switched to graphics
67 * mode. The display is not supposed to return to text mode, except
68 * in case of a bug check. The bug check will call HalDisplayString
69 * to output a string to the text screen. HAL will notice that it
70 * currently doesn't own the display and will re-take ownership, by
71 * calling the callback function passed to HalAcquireDisplayOwnership.
72 * After the bugcheck, execution is halted. So, under NT, the only
73 * possible sequence of display modes is text mode -> graphics mode ->
74 * text mode (the latter hopefully happening very infrequently).
76 * Things are a little bit different in the current state of ReactOS.
77 * We want to have a functional interactive text mode. We should be
78 * able to switch from text mode to graphics mode when a GUI app is
79 * started and switch back to text mode when it's finished. Then, when
80 * another GUI app is started, another switch to and from graphics mode
81 * is possible. Also, when the system bugchecks in graphics mode we want
82 * to switch back to text mode to show the registers and stack trace.
83 * Last but not least, HalDisplayString is used a lot more in ReactOS,
84 * e.g. to print debug messages when the /DEBUGPORT=SCREEN boot option
86 * 3 Components are involved in Reactos: HAL, BLUE.SYS and VIDEOPRT.SYS.
87 * As in NT, on boot HAL owns the display. When entering the text mode
88 * command interpreter, BLUE.SYS kicks in. It will write directly to the
89 * screen, more or less behind HALs back.
90 * When a GUI app is started, WIN32K.SYS will open the DISPLAY device.
91 * This open call will end up in VIDEOPRT.SYS. That component will then
92 * take ownership of the display by calling HalAcquireDisplayOwnership.
93 * When the GUI app terminates (WIN32K.SYS will close the DISPLAY device),
94 * we want to give ownership of the display back to HAL. Using the
95 * standard exported HAL functions, that's a bit of a problem, because
96 * there is no function defined to do that. In NT, this is handled by
97 * HalDisplayString, but that solution isn't satisfactory in ReactOS,
98 * because HalDisplayString is (in some cases) also used to output debug
99 * messages. If we do it the NT way, the first debug message output while
100 * in graphics mode would switch the display back to text mode.
101 * So, instead, if HalDisplayString detects that HAL doesn't have ownership
102 * of the display, it doesn't do anything.
103 * To return ownership to HAL, a new function is exported,
104 * HalReleaseDisplayOwnership. This function is called by the DISPLAY
105 * device Close routine in VIDEOPRT.SYS. It is also called at the beginning
106 * of a bug check, so HalDisplayString is activated again.
107 * Now, while the display is in graphics mode (not owned by HAL), BLUE.SYS
108 * should also refrain from writing to the screen buffer. The text mode
109 * screen buffer might overlap the graphics mode screen buffer, so changing
110 * something in the text mode buffer might mess up the graphics screen. To
111 * allow BLUE.SYS to detect if HAL owns the display, another new function is
112 * exported, HalQueryDisplayOwnership. BLUE.SYS will call this function to
113 * check if it's allowed to touch the text mode buffer.
115 * In an ideal world, when HAL takes ownership of the display, it should set
116 * up the CRT using real-mode (actually V86 mode, but who cares) INT 0x10
117 * calls. Unfortunately, this will require HAL to setup a real-mode interrupt
118 * table etc. So, we chickened out of that by having the loader set up the
119 * display before switching to protected mode. If HAL is given back ownership
120 * after a GUI app terminates, the INT 0x10 calls are made by VIDEOPRT.SYS,
121 * since there is already support for them via the VideoPortInt10 routine.
124 #include <ddk/ntddk.h>
127 #define SCREEN_SYNCHRONIZATION
129 #define VGA_AC_INDEX 0x3c0
130 #define VGA_AC_READ 0x3c1
131 #define VGA_AC_WRITE 0x3c0
133 #define VGA_MISC_WRITE 0x3c2
135 #define VGA_SEQ_INDEX 0x3c4
136 #define VGA_SEQ_DATA 0x3c5
138 #define VGA_DAC_MASK 0x3c6
139 #define VGA_DAC_READ_INDEX 0x3c7
140 #define VGA_DAC_WRITE_INDEX 0x3c8
141 #define VGA_DAC_DATA 0x3c9
142 #define VGA_FEATURE_READ 0x3ca
143 #define VGA_MISC_READ 0x3cc
145 #define VGA_GC_INDEX 0x3ce
146 #define VGA_GC_DATA 0x3cf
148 #define VGA_CRTC_INDEX 0x3d4
149 #define VGA_CRTC_DATA 0x3d5
151 #define VGA_INSTAT_READ 0x3da
153 #define VGA_SEQ_NUM_REGISTERS 5
154 #define VGA_CRTC_NUM_REGISTERS 25
155 #define VGA_GC_NUM_REGISTERS 9
156 #define VGA_AC_NUM_REGISTERS 21
158 #define CRTC_COLUMNS 0x01
159 #define CRTC_OVERFLOW 0x07
160 #define CRTC_ROWS 0x12
161 #define CRTC_SCANLINES 0x09
163 #define CRTC_CURHI 0x0e
164 #define CRTC_CURLO 0x0f
167 #define CHAR_ATTRIBUTE_BLACK 0x00 /* black on black */
168 #define CHAR_ATTRIBUTE 0x17 /* grey on blue */
170 #define FONT_AMOUNT (8*8192)
172 /* VARIABLES ****************************************************************/
174 static ULONG CursorX = 0; /* Cursor Position */
175 static ULONG CursorY = 0;
176 static ULONG SizeX = 80; /* Display size */
177 static ULONG SizeY = 25;
179 static BOOLEAN DisplayInitialized = FALSE;
180 static BOOLEAN HalOwnsDisplay = TRUE;
182 static WORD *VideoBuffer = NULL;
183 static PUCHAR GraphVideoBuffer = NULL;
185 static PHAL_RESET_DISPLAY_PARAMETERS HalResetDisplayParameters = NULL;
187 static UCHAR SavedTextPalette[768];
188 static UCHAR SavedTextMiscOutReg;
189 static UCHAR SavedTextCrtcReg[VGA_CRTC_NUM_REGISTERS];
190 static UCHAR SavedTextAcReg[VGA_AC_NUM_REGISTERS];
191 static UCHAR SavedTextGcReg[VGA_GC_NUM_REGISTERS];
192 static UCHAR SavedTextSeqReg[VGA_SEQ_NUM_REGISTERS];
193 static UCHAR SavedTextFont[2][FONT_AMOUNT];
194 static BOOL TextPaletteEnabled = FALSE;
196 /* PRIVATE FUNCTIONS *********************************************************/
199 HalClearDisplay (UCHAR CharAttribute)
201 WORD *ptr = (WORD*)VideoBuffer;
204 for (i = 0; i < SizeX * SizeY; i++, ptr++)
205 *ptr = ((CharAttribute << 8) + ' ');
212 /* STATIC FUNCTIONS *********************************************************/
215 HalScrollDisplay (VOID)
220 ptr = VideoBuffer + SizeX;
221 RtlMoveMemory(VideoBuffer,
223 SizeX * (SizeY - 1) * 2);
225 ptr = VideoBuffer + (SizeX * (SizeY - 1));
226 for (i = 0; i < SizeX; i++, ptr++)
228 *ptr = (CHAR_ATTRIBUTE << 8) + ' ';
233 HalPutCharacter (CHAR Character)
237 ptr = VideoBuffer + ((CursorY * SizeX) + CursorX);
238 *ptr = (CHAR_ATTRIBUTE << 8) + Character;
242 HalDisablePalette(VOID)
244 (VOID)READ_PORT_UCHAR((PUCHAR)VGA_INSTAT_READ);
245 WRITE_PORT_UCHAR((PUCHAR)VGA_AC_INDEX, 0x20);
246 TextPaletteEnabled = FALSE;
250 HalEnablePalette(VOID)
252 (VOID)READ_PORT_UCHAR((PUCHAR)VGA_INSTAT_READ);
253 WRITE_PORT_UCHAR((PUCHAR)VGA_AC_INDEX, 0x00);
254 TextPaletteEnabled = TRUE;
257 UCHAR STATIC FASTCALL
258 HalReadGc(ULONG Index)
260 WRITE_PORT_UCHAR((PUCHAR)VGA_GC_INDEX, Index);
261 return(READ_PORT_UCHAR((PUCHAR)VGA_GC_DATA));
265 HalWriteGc(ULONG Index, UCHAR Value)
267 WRITE_PORT_UCHAR((PUCHAR)VGA_GC_INDEX, Index);
268 WRITE_PORT_UCHAR((PUCHAR)VGA_GC_DATA, Value);
271 UCHAR STATIC FASTCALL
272 HalReadSeq(ULONG Index)
274 WRITE_PORT_UCHAR((PUCHAR)VGA_SEQ_INDEX, Index);
275 return(READ_PORT_UCHAR((PUCHAR)VGA_SEQ_DATA));
279 HalWriteSeq(ULONG Index, UCHAR Value)
281 WRITE_PORT_UCHAR((PUCHAR)VGA_SEQ_INDEX, Index);
282 WRITE_PORT_UCHAR((PUCHAR)VGA_SEQ_DATA, Value);
286 HalWriteAc(ULONG Index, UCHAR Value)
288 if (TextPaletteEnabled)
296 (VOID)READ_PORT_UCHAR((PUCHAR)VGA_INSTAT_READ);
297 WRITE_PORT_UCHAR((PUCHAR)VGA_AC_INDEX, Index);
298 WRITE_PORT_UCHAR((PUCHAR)VGA_AC_WRITE, Value);
301 UCHAR STATIC FASTCALL
302 HalReadAc(ULONG Index)
304 if (TextPaletteEnabled)
312 (VOID)READ_PORT_UCHAR((PUCHAR)VGA_INSTAT_READ);
313 WRITE_PORT_UCHAR((PUCHAR)VGA_AC_INDEX, Index);
314 return(READ_PORT_UCHAR((PUCHAR)VGA_AC_READ));
318 HalWriteCrtc(ULONG Index, UCHAR Value)
320 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, Index);
321 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA, Value);
324 UCHAR STATIC FASTCALL
325 HalReadCrtc(ULONG Index)
327 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, Index);
328 return(READ_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA));
332 HalResetSeq(BOOL Start)
336 HalWriteSeq(0x00, 0x01);
340 HalWriteSeq(0x00, 0x03);
345 HalBlankScreen(BOOL On)
349 Scrn = HalReadSeq(0x01);
361 HalWriteSeq(0x01, Scrn);
369 UCHAR MiscOut, Gc4, Gc5, Gc6, Seq2, Seq4;
372 /* Check if we are already in graphics mode. */
373 Attr10 = HalReadAc(0x10);
379 /* Save registers. */
380 MiscOut = READ_PORT_UCHAR((PUCHAR)VGA_MISC_READ);
381 Gc4 = HalReadGc(0x04);
382 Gc5 = HalReadGc(0x05);
383 Gc6 = HalReadGc(0x06);
384 Seq2 = HalReadSeq(0x02);
385 Seq4 = HalReadSeq(0x04);
387 /* Force colour mode. */
388 WRITE_PORT_UCHAR((PUCHAR)VGA_MISC_WRITE, MiscOut | 0x01);
390 HalBlankScreen(FALSE);
392 for (i = 0; i < 2; i++)
395 HalWriteSeq(0x02, 0x04 << i); /* Write to plane 2 or 3 */
396 HalWriteSeq(0x04, 0x06); /* Enable plane graphics. */
397 HalWriteGc(0x04, 0x02 + i); /* Read plane 2 or 3 */
398 HalWriteGc(0x05, 0x00); /* Write mode 0; read mode 0 */
399 HalWriteGc(0x06, 0x05); /* Set graphics. */
400 memcpy(SavedTextFont[i], GraphVideoBuffer, FONT_AMOUNT);
403 /* Restore registers. */
404 HalWriteAc(0x10, Attr10);
405 HalWriteSeq(0x02, Seq2);
406 HalWriteSeq(0x04, Seq4);
407 HalWriteGc(0x04, Gc4);
408 HalWriteGc(0x05, Gc5);
409 HalWriteGc(0x06, Gc6);
410 WRITE_PORT_UCHAR((PUCHAR)VGA_MISC_WRITE, MiscOut);
412 HalBlankScreen(TRUE);
420 SavedTextMiscOutReg = READ_PORT_UCHAR((PUCHAR)VGA_MISC_READ);
422 for (i = 0; i < VGA_CRTC_NUM_REGISTERS; i++)
424 SavedTextCrtcReg[i] = HalReadCrtc(i);
428 for (i = 0; i < VGA_AC_NUM_REGISTERS; i++)
430 SavedTextAcReg[i] = HalReadAc(i);
434 for (i = 0; i < VGA_GC_NUM_REGISTERS; i++)
436 SavedTextGcReg[i] = HalReadGc(i);
439 for (i = 0; i < VGA_SEQ_NUM_REGISTERS; i++)
441 SavedTextSeqReg[i] = HalReadSeq(i);
448 (VOID)READ_PORT_UCHAR((PUCHAR)VGA_INSTAT_READ);
449 (VOID)READ_PORT_UCHAR((PUCHAR)VGA_INSTAT_READ);
456 WRITE_PORT_UCHAR((PUCHAR)VGA_DAC_MASK, 0xFF);
457 WRITE_PORT_UCHAR((PUCHAR)VGA_DAC_READ_INDEX, 0x00);
458 for (i = 0; i < 768; i++)
460 SavedTextPalette[i] = READ_PORT_UCHAR((PUCHAR)VGA_DAC_DATA);
468 UCHAR MiscOut, Attr10, Gc1, Gc3, Gc4, Gc5, Gc6, Gc8;
472 /* Save registers. */
473 MiscOut = READ_PORT_UCHAR((PUCHAR)VGA_MISC_READ);
474 Attr10 = HalReadAc(0x10);
475 Gc1 = HalReadGc(0x01);
476 Gc3 = HalReadGc(0x03);
477 Gc4 = HalReadGc(0x04);
478 Gc5 = HalReadGc(0x05);
479 Gc6 = HalReadGc(0x06);
480 Gc8 = HalReadGc(0x08);
481 Seq2 = HalReadSeq(0x02);
482 Seq4 = HalReadSeq(0x04);
484 /* Force into colour mode. */
485 WRITE_PORT_UCHAR((PUCHAR)VGA_MISC_WRITE, MiscOut | 0x10);
487 HalBlankScreen(FALSE);
489 HalWriteGc(0x03, 0x00); /* Don't rotate; write unmodified. */
490 HalWriteGc(0x08, 0xFF); /* Write all bits. */
491 HalWriteGc(0x01, 0x00); /* All planes from CPU. */
493 for (i = 0; i < 2; i++)
495 HalWriteSeq(0x02, 0x04 << i); /* Write to plane 2 or 3 */
496 HalWriteSeq(0x04, 0x06); /* Enable plane graphics. */
497 HalWriteGc(0x04, 0x02 + i); /* Read plane 2 or 3 */
498 HalWriteGc(0x05, 0x00); /* Write mode 0; read mode 0. */
499 HalWriteGc(0x06, 0x05); /* Set graphics. */
500 memcpy(GraphVideoBuffer, SavedTextFont[i], FONT_AMOUNT);
503 HalBlankScreen(TRUE);
505 /* Restore registers. */
506 WRITE_PORT_UCHAR((PUCHAR)VGA_MISC_WRITE, MiscOut);
507 HalWriteAc(0x10, Attr10);
508 HalWriteGc(0x01, Gc1);
509 HalWriteGc(0x03, Gc3);
510 HalWriteGc(0x04, Gc4);
511 HalWriteGc(0x05, Gc5);
512 HalWriteGc(0x06, Gc6);
513 HalWriteGc(0x08, Gc8);
514 HalWriteSeq(0x02, Seq2);
515 HalWriteSeq(0x04, Seq4);
523 WRITE_PORT_UCHAR((PUCHAR)VGA_MISC_WRITE, SavedTextMiscOutReg);
525 for (i = 1; i < VGA_SEQ_NUM_REGISTERS; i++)
527 HalWriteSeq(i, SavedTextSeqReg[i]);
530 /* Unlock CRTC registers 0-7 */
531 HalWriteCrtc(17, SavedTextCrtcReg[17] & ~0x80);
533 for (i = 0; i < VGA_CRTC_NUM_REGISTERS; i++)
535 HalWriteCrtc(i, SavedTextCrtcReg[i]);
538 for (i = 0; i < VGA_GC_NUM_REGISTERS; i++)
540 HalWriteGc(i, SavedTextGcReg[i]);
544 for (i = 0; i < VGA_AC_NUM_REGISTERS; i++)
546 HalWriteAc(i, SavedTextAcReg[i]);
552 HalRestorePalette(VOID)
555 WRITE_PORT_UCHAR((PUCHAR)VGA_DAC_MASK, 0xFF);
556 WRITE_PORT_UCHAR((PUCHAR)VGA_DAC_WRITE_INDEX, 0x00);
557 for (i = 0; i < 768; i++)
559 WRITE_PORT_UCHAR((PUCHAR)VGA_DAC_DATA, SavedTextPalette[i]);
565 /* PRIVATE FUNCTIONS ********************************************************/
568 HalInitializeDisplay (PLOADER_PARAMETER_BLOCK LoaderBlock)
570 * FUNCTION: Initalize the display
572 * InitParameters = Parameters setup by the boot loader
575 if (DisplayInitialized == FALSE)
580 VideoBuffer = (WORD *)(0xd0000000 + 0xb8000);
581 GraphVideoBuffer = (PUCHAR)(0xd0000000 + 0xa0000);
582 // VideoBuffer = HalMapPhysicalMemory (0xb8000, 2);
584 /* Set cursor position */
585 // CursorX = LoaderBlock->cursorx;
586 // CursorY = LoaderBlock->cursory;
590 /* read screen size from the crtc */
591 /* FIXME: screen size should be read from the boot parameters */
592 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_COLUMNS);
593 SizeX = READ_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA) + 1;
594 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_ROWS);
595 SizeY = READ_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA);
596 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_OVERFLOW);
597 Data = READ_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA);
598 SizeY |= (((Data & 0x02) << 7) | ((Data & 0x40) << 3));
600 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_SCANLINES);
601 ScanLines = (READ_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA) & 0x1F) + 1;
602 SizeY = SizeY / ScanLines;
607 HalClearDisplay(CHAR_ATTRIBUTE_BLACK);
609 DisplayInitialized = TRUE;
612 Save the VGA state at this point so we can restore it on a bugcheck.
621 /* PUBLIC FUNCTIONS *********************************************************/
624 HalReleaseDisplayOwnership()
626 * FUNCTION: Release ownership of display back to HAL
629 if (HalResetDisplayParameters == NULL)
632 if (HalOwnsDisplay == TRUE)
635 if (!HalResetDisplayParameters(SizeX, SizeY))
641 HalOwnsDisplay = TRUE;
642 HalClearDisplay(CHAR_ATTRIBUTE);
647 HalAcquireDisplayOwnership(IN PHAL_RESET_DISPLAY_PARAMETERS ResetDisplayParameters)
651 * ResetDisplayParameters = Pointer to a driver specific
655 HalOwnsDisplay = FALSE;
656 HalResetDisplayParameters = ResetDisplayParameters;
660 HalDisplayString(IN PCH String)
662 * FUNCTION: Switches the screen to HAL console mode (BSOD) if not there
663 * already and displays a string
665 * string = ASCII string to display
666 * NOTE: Use with care because there is no support for returning from BSOD
671 #ifdef SCREEN_SYNCHRONIZATION
674 static KSPIN_LOCK Lock;
677 /* See comment at top of file */
678 if (! HalOwnsDisplay)
687 KeAcquireSpinLockAtDpcLevel(&Lock);
690 if (HalOwnsDisplay == FALSE)
692 HalReleaseDisplayOwnership();
696 #ifdef SCREEN_SYNCHRONIZATION
697 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_CURHI);
698 offset = READ_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA)<<8;
699 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_CURLO);
700 offset += READ_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA);
702 CursorY = offset / SizeX;
703 CursorX = offset % SizeX;
713 else if (*pch == '\b')
720 else if (*pch != '\r')
722 HalPutCharacter (*pch);
725 if (CursorX >= SizeX)
732 if (CursorY >= SizeY)
741 #ifdef SCREEN_SYNCHRONIZATION
742 offset = (CursorY * SizeX) + CursorX;
744 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_CURLO);
745 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA, offset & 0xff);
746 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_INDEX, CRTC_CURHI);
747 WRITE_PORT_UCHAR((PUCHAR)VGA_CRTC_DATA, (offset >> 8) & 0xff);
749 KeReleaseSpinLockFromDpcLevel(&Lock);
754 HalQueryDisplayParameters(OUT PULONG DispSizeX,
755 OUT PULONG DispSizeY,
756 OUT PULONG CursorPosX,
757 OUT PULONG CursorPosY)
764 *CursorPosX = CursorX;
766 *CursorPosY = CursorY;
771 HalSetDisplayParameters(IN ULONG CursorPosX,
774 CursorX = (CursorPosX < SizeX) ? CursorPosX : SizeX - 1;
775 CursorY = (CursorPosY < SizeY) ? CursorPosY : SizeY - 1;
779 HalQueryDisplayOwnership()
781 return ! HalOwnsDisplay;