xref: /linux/drivers/video/console/vgacon.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
1 /*
2  *  linux/drivers/video/vgacon.c -- Low level VGA based console driver
3  *
4  *	Created 28 Sep 1997 by Geert Uytterhoeven
5  *
6  *	Rewritten by Martin Mares <mj@ucw.cz>, July 1998
7  *
8  *  This file is based on the old console.c, vga.c and vesa_blank.c drivers.
9  *
10  *	Copyright (C) 1991, 1992  Linus Torvalds
11  *			    1995  Jay Estabrook
12  *
13  *	User definable mapping table and font loading by Eugene G. Crosser,
14  *	<crosser@average.org>
15  *
16  *	Improved loadable font/UTF-8 support by H. Peter Anvin
17  *	Feb-Sep 1995 <peter.anvin@linux.org>
18  *
19  *	Colour palette handling, by Simon Tatham
20  *	17-Jun-95 <sgt20@cam.ac.uk>
21  *
22  *	if 512 char mode is already enabled don't re-enable it,
23  *	because it causes screen to flicker, by Mitja Horvat
24  *	5-May-96 <mitja.horvat@guest.arnes.si>
25  *
26  *	Use 2 outw instead of 4 outb_p to reduce erroneous text
27  *	flashing on RHS of screen during heavy console scrolling .
28  *	Oct 1996, Paul Gortmaker.
29  *
30  *
31  *  This file is subject to the terms and conditions of the GNU General Public
32  *  License.  See the file COPYING in the main directory of this archive for
33  *  more details.
34  */
35 
36 #include <linux/config.h>
37 #include <linux/module.h>
38 #include <linux/types.h>
39 #include <linux/sched.h>
40 #include <linux/fs.h>
41 #include <linux/kernel.h>
42 #include <linux/tty.h>
43 #include <linux/console.h>
44 #include <linux/string.h>
45 #include <linux/kd.h>
46 #include <linux/slab.h>
47 #include <linux/vt_kern.h>
48 #include <linux/selection.h>
49 #include <linux/spinlock.h>
50 #include <linux/ioport.h>
51 #include <linux/init.h>
52 #include <linux/smp_lock.h>
53 #include <video/vga.h>
54 #include <asm/io.h>
55 
56 static DEFINE_SPINLOCK(vga_lock);
57 static int cursor_size_lastfrom;
58 static int cursor_size_lastto;
59 static u32 vgacon_xres;
60 static u32 vgacon_yres;
61 static struct vgastate state;
62 
63 #define BLANK 0x0020
64 
65 #define CAN_LOAD_EGA_FONTS	/* undefine if the user must not do this */
66 #define CAN_LOAD_PALETTE	/* undefine if the user must not do this */
67 
68 /* You really do _NOT_ want to define this, unless you have buggy
69  * Trident VGA which will resize cursor when moving it between column
70  * 15 & 16. If you define this and your VGA is OK, inverse bug will
71  * appear.
72  */
73 #undef TRIDENT_GLITCH
74 #define VGA_FONTWIDTH       8   /* VGA does not support fontwidths != 8 */
75 /*
76  *  Interface used by the world
77  */
78 
79 static const char *vgacon_startup(void);
80 static void vgacon_init(struct vc_data *c, int init);
81 static void vgacon_deinit(struct vc_data *c);
82 static void vgacon_cursor(struct vc_data *c, int mode);
83 static int vgacon_switch(struct vc_data *c);
84 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch);
85 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table);
86 static int vgacon_scrolldelta(struct vc_data *c, int lines);
87 static int vgacon_set_origin(struct vc_data *c);
88 static void vgacon_save_screen(struct vc_data *c);
89 static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
90 			 int lines);
91 static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
92 			    u8 blink, u8 underline, u8 reverse);
93 static void vgacon_invert_region(struct vc_data *c, u16 * p, int count);
94 static unsigned long vgacon_uni_pagedir[2];
95 
96 /* Description of the hardware situation */
97 static unsigned long	vga_vram_base;		/* Base of video memory */
98 static unsigned long	vga_vram_end;		/* End of video memory */
99 static int		vga_vram_size;		/* Size of video memory */
100 static u16		vga_video_port_reg;	/* Video register select port */
101 static u16		vga_video_port_val;	/* Video register value port */
102 static unsigned int	vga_video_num_columns;	/* Number of text columns */
103 static unsigned int	vga_video_num_lines;	/* Number of text lines */
104 static int		vga_can_do_color = 0;	/* Do we support colors? */
105 static unsigned int	vga_default_font_height;/* Height of default screen font */
106 static unsigned char	vga_video_type;		/* Card type */
107 static unsigned char	vga_hardscroll_enabled;
108 static unsigned char	vga_hardscroll_user_enable = 1;
109 static unsigned char	vga_font_is_default = 1;
110 static int		vga_vesa_blanked;
111 static int 		vga_palette_blanked;
112 static int 		vga_is_gfx;
113 static int 		vga_512_chars;
114 static int 		vga_video_font_height;
115 static int 		vga_scan_lines;
116 static unsigned int 	vga_rolled_over = 0;
117 static int              vga_init_done;
118 
119 static int __init no_scroll(char *str)
120 {
121 	/*
122 	 * Disabling scrollback is required for the Braillex ib80-piezo
123 	 * Braille reader made by F.H. Papenmeier (Germany).
124 	 * Use the "no-scroll" bootflag.
125 	 */
126 	vga_hardscroll_user_enable = vga_hardscroll_enabled = 0;
127 	return 1;
128 }
129 
130 __setup("no-scroll", no_scroll);
131 
132 /*
133  * By replacing the four outb_p with two back to back outw, we can reduce
134  * the window of opportunity to see text mislocated to the RHS of the
135  * console during heavy scrolling activity. However there is the remote
136  * possibility that some pre-dinosaur hardware won't like the back to back
137  * I/O. Since the Xservers get away with it, we should be able to as well.
138  */
139 static inline void write_vga(unsigned char reg, unsigned int val)
140 {
141 	unsigned int v1, v2;
142 	unsigned long flags;
143 
144 	/*
145 	 * ddprintk might set the console position from interrupt
146 	 * handlers, thus the write has to be IRQ-atomic.
147 	 */
148 	spin_lock_irqsave(&vga_lock, flags);
149 
150 #ifndef SLOW_VGA
151 	v1 = reg + (val & 0xff00);
152 	v2 = reg + 1 + ((val << 8) & 0xff00);
153 	outw(v1, vga_video_port_reg);
154 	outw(v2, vga_video_port_reg);
155 #else
156 	outb_p(reg, vga_video_port_reg);
157 	outb_p(val >> 8, vga_video_port_val);
158 	outb_p(reg + 1, vga_video_port_reg);
159 	outb_p(val & 0xff, vga_video_port_val);
160 #endif
161 	spin_unlock_irqrestore(&vga_lock, flags);
162 }
163 
164 static inline void vga_set_mem_top(struct vc_data *c)
165 {
166 	write_vga(12, (c->vc_visible_origin - vga_vram_base) / 2);
167 }
168 
169 #ifdef CONFIG_VGACON_SOFT_SCROLLBACK
170 #include <linux/bootmem.h>
171 /* software scrollback */
172 static void *vgacon_scrollback;
173 static int vgacon_scrollback_tail;
174 static int vgacon_scrollback_size;
175 static int vgacon_scrollback_rows;
176 static int vgacon_scrollback_cnt;
177 static int vgacon_scrollback_cur;
178 static int vgacon_scrollback_save;
179 static int vgacon_scrollback_restore;
180 
181 static void vgacon_scrollback_init(int pitch)
182 {
183 	int rows = CONFIG_VGACON_SOFT_SCROLLBACK_SIZE * 1024/pitch;
184 
185 	if (vgacon_scrollback) {
186 		vgacon_scrollback_cnt  = 0;
187 		vgacon_scrollback_tail = 0;
188 		vgacon_scrollback_cur  = 0;
189 		vgacon_scrollback_rows = rows - 1;
190 		vgacon_scrollback_size = rows * pitch;
191 	}
192 }
193 
194 static void vgacon_scrollback_startup(void)
195 {
196 	vgacon_scrollback = alloc_bootmem(CONFIG_VGACON_SOFT_SCROLLBACK_SIZE
197 					  * 1024);
198 	vgacon_scrollback_init(vga_video_num_columns * 2);
199 }
200 
201 static void vgacon_scrollback_update(struct vc_data *c, int t, int count)
202 {
203 	void *p;
204 
205 	if (!vgacon_scrollback_size || c->vc_num != fg_console)
206 		return;
207 
208 	p = (void *) (c->vc_origin + t * c->vc_size_row);
209 
210 	while (count--) {
211 		scr_memcpyw(vgacon_scrollback + vgacon_scrollback_tail,
212 			    p, c->vc_size_row);
213 		vgacon_scrollback_cnt++;
214 		p += c->vc_size_row;
215 		vgacon_scrollback_tail += c->vc_size_row;
216 
217 		if (vgacon_scrollback_tail >= vgacon_scrollback_size)
218 			vgacon_scrollback_tail = 0;
219 
220 		if (vgacon_scrollback_cnt > vgacon_scrollback_rows)
221 			vgacon_scrollback_cnt = vgacon_scrollback_rows;
222 
223 		vgacon_scrollback_cur = vgacon_scrollback_cnt;
224 	}
225 }
226 
227 static void vgacon_restore_screen(struct vc_data *c)
228 {
229 	vgacon_scrollback_save = 0;
230 
231 	if (!vga_is_gfx && !vgacon_scrollback_restore) {
232 		scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
233 			    c->vc_screenbuf_size > vga_vram_size ?
234 			    vga_vram_size : c->vc_screenbuf_size);
235 		vgacon_scrollback_restore = 1;
236 		vgacon_scrollback_cur = vgacon_scrollback_cnt;
237 	}
238 }
239 
240 static int vgacon_scrolldelta(struct vc_data *c, int lines)
241 {
242 	int start, end, count, soff, diff;
243 	void *d, *s;
244 
245 	if (!lines) {
246 		c->vc_visible_origin = c->vc_origin;
247 		vga_set_mem_top(c);
248 		return 1;
249 	}
250 
251 	if (!vgacon_scrollback)
252 		return 1;
253 
254 	if (!vgacon_scrollback_save) {
255 		vgacon_cursor(c, CM_ERASE);
256 		vgacon_save_screen(c);
257 		vgacon_scrollback_save = 1;
258 	}
259 
260 	vgacon_scrollback_restore = 0;
261 	start = vgacon_scrollback_cur + lines;
262 	end = start + abs(lines);
263 
264 	if (start < 0)
265 		start = 0;
266 
267 	if (start > vgacon_scrollback_cnt)
268 		start = vgacon_scrollback_cnt;
269 
270 	if (end < 0)
271 		end = 0;
272 
273 	if (end > vgacon_scrollback_cnt)
274 		end = vgacon_scrollback_cnt;
275 
276 	vgacon_scrollback_cur = start;
277 	count = end - start;
278 	soff = vgacon_scrollback_tail - ((vgacon_scrollback_cnt - end) *
279 					 c->vc_size_row);
280 	soff -= count * c->vc_size_row;
281 
282 	if (soff < 0)
283 		soff += vgacon_scrollback_size;
284 
285 	count = vgacon_scrollback_cnt - start;
286 
287 	if (count > c->vc_rows)
288 		count = c->vc_rows;
289 
290 	diff = c->vc_rows - count;
291 
292 	d = (void *) c->vc_origin;
293 	s = (void *) c->vc_screenbuf;
294 
295 	while (count--) {
296 		scr_memcpyw(d, vgacon_scrollback + soff, c->vc_size_row);
297 		d += c->vc_size_row;
298 		soff += c->vc_size_row;
299 
300 		if (soff >= vgacon_scrollback_size)
301 			soff = 0;
302 	}
303 
304 	if (diff == c->vc_rows) {
305 		vgacon_cursor(c, CM_MOVE);
306 	} else {
307 		while (diff--) {
308 			scr_memcpyw(d, s, c->vc_size_row);
309 			d += c->vc_size_row;
310 			s += c->vc_size_row;
311 		}
312 	}
313 
314 	return 1;
315 }
316 #else
317 #define vgacon_scrollback_startup(...) do { } while (0)
318 #define vgacon_scrollback_init(...)    do { } while (0)
319 #define vgacon_scrollback_update(...)  do { } while (0)
320 
321 static void vgacon_restore_screen(struct vc_data *c)
322 {
323 	if (c->vc_origin != c->vc_visible_origin)
324 		vgacon_scrolldelta(c, 0);
325 }
326 
327 static int vgacon_scrolldelta(struct vc_data *c, int lines)
328 {
329 	if (!lines)		/* Turn scrollback off */
330 		c->vc_visible_origin = c->vc_origin;
331 	else {
332 		int margin = c->vc_size_row * 4;
333 		int ul, we, p, st;
334 
335 		if (vga_rolled_over >
336 		    (c->vc_scr_end - vga_vram_base) + margin) {
337 			ul = c->vc_scr_end - vga_vram_base;
338 			we = vga_rolled_over + c->vc_size_row;
339 		} else {
340 			ul = 0;
341 			we = vga_vram_size;
342 		}
343 		p = (c->vc_visible_origin - vga_vram_base - ul + we) % we +
344 		    lines * c->vc_size_row;
345 		st = (c->vc_origin - vga_vram_base - ul + we) % we;
346 		if (st < 2 * margin)
347 			margin = 0;
348 		if (p < margin)
349 			p = 0;
350 		if (p > st - margin)
351 			p = st;
352 		c->vc_visible_origin = vga_vram_base + (p + ul) % we;
353 	}
354 	vga_set_mem_top(c);
355 	return 1;
356 }
357 #endif /* CONFIG_VGACON_SOFT_SCROLLBACK */
358 
359 static const char *vgacon_startup(void)
360 {
361 	const char *display_desc = NULL;
362 	u16 saved1, saved2;
363 	volatile u16 *p;
364 
365 	if (ORIG_VIDEO_ISVGA == VIDEO_TYPE_VLFB) {
366 	      no_vga:
367 #ifdef CONFIG_DUMMY_CONSOLE
368 		conswitchp = &dummy_con;
369 		return conswitchp->con_startup();
370 #else
371 		return NULL;
372 #endif
373 	}
374 
375 	/* VGA16 modes are not handled by VGACON */
376 	if ((ORIG_VIDEO_MODE == 0x0D) ||	/* 320x200/4 */
377 	    (ORIG_VIDEO_MODE == 0x0E) ||	/* 640x200/4 */
378 	    (ORIG_VIDEO_MODE == 0x10) ||	/* 640x350/4 */
379 	    (ORIG_VIDEO_MODE == 0x12) ||	/* 640x480/4 */
380 	    (ORIG_VIDEO_MODE == 0x6A))	/* 800x600/4, 0x6A is very common */
381 		goto no_vga;
382 
383 	vga_video_num_lines = ORIG_VIDEO_LINES;
384 	vga_video_num_columns = ORIG_VIDEO_COLS;
385 	state.vgabase = NULL;
386 
387 	if (ORIG_VIDEO_MODE == 7) {	/* Is this a monochrome display? */
388 		vga_vram_base = 0xb0000;
389 		vga_video_port_reg = VGA_CRT_IM;
390 		vga_video_port_val = VGA_CRT_DM;
391 		if ((ORIG_VIDEO_EGA_BX & 0xff) != 0x10) {
392 			static struct resource ega_console_resource =
393 			    { .name = "ega", .start = 0x3B0, .end = 0x3BF };
394 			vga_video_type = VIDEO_TYPE_EGAM;
395 			vga_vram_size = 0x8000;
396 			display_desc = "EGA+";
397 			request_resource(&ioport_resource,
398 					 &ega_console_resource);
399 		} else {
400 			static struct resource mda1_console_resource =
401 			    { .name = "mda", .start = 0x3B0, .end = 0x3BB };
402 			static struct resource mda2_console_resource =
403 			    { .name = "mda", .start = 0x3BF, .end = 0x3BF };
404 			vga_video_type = VIDEO_TYPE_MDA;
405 			vga_vram_size = 0x2000;
406 			display_desc = "*MDA";
407 			request_resource(&ioport_resource,
408 					 &mda1_console_resource);
409 			request_resource(&ioport_resource,
410 					 &mda2_console_resource);
411 			vga_video_font_height = 14;
412 		}
413 	} else {
414 		/* If not, it is color. */
415 		vga_can_do_color = 1;
416 		vga_vram_base = 0xb8000;
417 		vga_video_port_reg = VGA_CRT_IC;
418 		vga_video_port_val = VGA_CRT_DC;
419 		if ((ORIG_VIDEO_EGA_BX & 0xff) != 0x10) {
420 			int i;
421 
422 			vga_vram_size = 0x8000;
423 
424 			if (!ORIG_VIDEO_ISVGA) {
425 				static struct resource ega_console_resource
426 				    = { .name = "ega", .start = 0x3C0, .end = 0x3DF };
427 				vga_video_type = VIDEO_TYPE_EGAC;
428 				display_desc = "EGA";
429 				request_resource(&ioport_resource,
430 						 &ega_console_resource);
431 			} else {
432 				static struct resource vga_console_resource
433 				    = { .name = "vga+", .start = 0x3C0, .end = 0x3DF };
434 				vga_video_type = VIDEO_TYPE_VGAC;
435 				display_desc = "VGA+";
436 				request_resource(&ioport_resource,
437 						 &vga_console_resource);
438 
439 #ifdef VGA_CAN_DO_64KB
440 				/*
441 				 * get 64K rather than 32K of video RAM.
442 				 * This doesn't actually work on all "VGA"
443 				 * controllers (it seems like setting MM=01
444 				 * and COE=1 isn't necessarily a good idea)
445 				 */
446 				vga_vram_base = 0xa0000;
447 				vga_vram_size = 0x10000;
448 				outb_p(6, VGA_GFX_I);
449 				outb_p(6, VGA_GFX_D);
450 #endif
451 				/*
452 				 * Normalise the palette registers, to point
453 				 * the 16 screen colours to the first 16
454 				 * DAC entries.
455 				 */
456 
457 				for (i = 0; i < 16; i++) {
458 					inb_p(VGA_IS1_RC);
459 					outb_p(i, VGA_ATT_W);
460 					outb_p(i, VGA_ATT_W);
461 				}
462 				outb_p(0x20, VGA_ATT_W);
463 
464 				/*
465 				 * Now set the DAC registers back to their
466 				 * default values
467 				 */
468 				for (i = 0; i < 16; i++) {
469 					outb_p(color_table[i], VGA_PEL_IW);
470 					outb_p(default_red[i], VGA_PEL_D);
471 					outb_p(default_grn[i], VGA_PEL_D);
472 					outb_p(default_blu[i], VGA_PEL_D);
473 				}
474 			}
475 		} else {
476 			static struct resource cga_console_resource =
477 			    { .name = "cga", .start = 0x3D4, .end = 0x3D5 };
478 			vga_video_type = VIDEO_TYPE_CGA;
479 			vga_vram_size = 0x2000;
480 			display_desc = "*CGA";
481 			request_resource(&ioport_resource,
482 					 &cga_console_resource);
483 			vga_video_font_height = 8;
484 		}
485 	}
486 
487 	vga_vram_base = VGA_MAP_MEM(vga_vram_base, vga_vram_size);
488 	vga_vram_end = vga_vram_base + vga_vram_size;
489 
490 	/*
491 	 *      Find out if there is a graphics card present.
492 	 *      Are there smarter methods around?
493 	 */
494 	p = (volatile u16 *) vga_vram_base;
495 	saved1 = scr_readw(p);
496 	saved2 = scr_readw(p + 1);
497 	scr_writew(0xAA55, p);
498 	scr_writew(0x55AA, p + 1);
499 	if (scr_readw(p) != 0xAA55 || scr_readw(p + 1) != 0x55AA) {
500 		scr_writew(saved1, p);
501 		scr_writew(saved2, p + 1);
502 		goto no_vga;
503 	}
504 	scr_writew(0x55AA, p);
505 	scr_writew(0xAA55, p + 1);
506 	if (scr_readw(p) != 0x55AA || scr_readw(p + 1) != 0xAA55) {
507 		scr_writew(saved1, p);
508 		scr_writew(saved2, p + 1);
509 		goto no_vga;
510 	}
511 	scr_writew(saved1, p);
512 	scr_writew(saved2, p + 1);
513 
514 	if (vga_video_type == VIDEO_TYPE_EGAC
515 	    || vga_video_type == VIDEO_TYPE_VGAC
516 	    || vga_video_type == VIDEO_TYPE_EGAM) {
517 		vga_hardscroll_enabled = vga_hardscroll_user_enable;
518 		vga_default_font_height = ORIG_VIDEO_POINTS;
519 		vga_video_font_height = ORIG_VIDEO_POINTS;
520 		/* This may be suboptimal but is a safe bet - go with it */
521 		vga_scan_lines =
522 		    vga_video_font_height * vga_video_num_lines;
523 	}
524 
525 	vgacon_xres = ORIG_VIDEO_COLS * VGA_FONTWIDTH;
526 	vgacon_yres = vga_scan_lines;
527 
528 	if (!vga_init_done) {
529 		vgacon_scrollback_startup();
530 		vga_init_done = 1;
531 	}
532 
533 	return display_desc;
534 }
535 
536 static void vgacon_init(struct vc_data *c, int init)
537 {
538 	unsigned long p;
539 
540 	/*
541 	 * We cannot be loaded as a module, therefore init is always 1,
542 	 * but vgacon_init can be called more than once, and init will
543 	 * not be 1.
544 	 */
545 	c->vc_can_do_color = vga_can_do_color;
546 
547 	/* set dimensions manually if init != 0 since vc_resize() will fail */
548 	if (init) {
549 		c->vc_cols = vga_video_num_columns;
550 		c->vc_rows = vga_video_num_lines;
551 	} else
552 		vc_resize(c, vga_video_num_columns, vga_video_num_lines);
553 
554 	c->vc_scan_lines = vga_scan_lines;
555 	c->vc_font.height = vga_video_font_height;
556 	c->vc_complement_mask = 0x7700;
557 	if (vga_512_chars)
558 		c->vc_hi_font_mask = 0x0800;
559 	p = *c->vc_uni_pagedir_loc;
560 	if (c->vc_uni_pagedir_loc == &c->vc_uni_pagedir ||
561 	    !--c->vc_uni_pagedir_loc[1])
562 		con_free_unimap(c);
563 	c->vc_uni_pagedir_loc = vgacon_uni_pagedir;
564 	vgacon_uni_pagedir[1]++;
565 	if (!vgacon_uni_pagedir[0] && p)
566 		con_set_default_unimap(c);
567 }
568 
569 static void vgacon_deinit(struct vc_data *c)
570 {
571 	/* When closing the last console, reset video origin */
572 	if (!--vgacon_uni_pagedir[1]) {
573 		c->vc_visible_origin = vga_vram_base;
574 		vga_set_mem_top(c);
575 		con_free_unimap(c);
576 	}
577 	c->vc_uni_pagedir_loc = &c->vc_uni_pagedir;
578 	con_set_default_unimap(c);
579 }
580 
581 static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
582 			    u8 blink, u8 underline, u8 reverse)
583 {
584 	u8 attr = color;
585 
586 	if (vga_can_do_color) {
587 		if (underline)
588 			attr = (attr & 0xf0) | c->vc_ulcolor;
589 		else if (intensity == 0)
590 			attr = (attr & 0xf0) | c->vc_halfcolor;
591 	}
592 	if (reverse)
593 		attr =
594 		    ((attr) & 0x88) | ((((attr) >> 4) | ((attr) << 4)) &
595 				       0x77);
596 	if (blink)
597 		attr ^= 0x80;
598 	if (intensity == 2)
599 		attr ^= 0x08;
600 	if (!vga_can_do_color) {
601 		if (underline)
602 			attr = (attr & 0xf8) | 0x01;
603 		else if (intensity == 0)
604 			attr = (attr & 0xf0) | 0x08;
605 	}
606 	return attr;
607 }
608 
609 static void vgacon_invert_region(struct vc_data *c, u16 * p, int count)
610 {
611 	int col = vga_can_do_color;
612 
613 	while (count--) {
614 		u16 a = scr_readw(p);
615 		if (col)
616 			a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) |
617 			    (((a) & 0x0700) << 4);
618 		else
619 			a ^= ((a & 0x0700) == 0x0100) ? 0x7000 : 0x7700;
620 		scr_writew(a, p++);
621 	}
622 }
623 
624 static void vgacon_set_cursor_size(int xpos, int from, int to)
625 {
626 	unsigned long flags;
627 	int curs, cure;
628 
629 #ifdef TRIDENT_GLITCH
630 	if (xpos < 16)
631 		from--, to--;
632 #endif
633 
634 	if ((from == cursor_size_lastfrom) && (to == cursor_size_lastto))
635 		return;
636 	cursor_size_lastfrom = from;
637 	cursor_size_lastto = to;
638 
639 	spin_lock_irqsave(&vga_lock, flags);
640 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
641 		outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
642 		curs = inb_p(vga_video_port_val);
643 		outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
644 		cure = inb_p(vga_video_port_val);
645 	} else {
646 		curs = 0;
647 		cure = 0;
648 	}
649 
650 	curs = (curs & 0xc0) | from;
651 	cure = (cure & 0xe0) | to;
652 
653 	outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
654 	outb_p(curs, vga_video_port_val);
655 	outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
656 	outb_p(cure, vga_video_port_val);
657 	spin_unlock_irqrestore(&vga_lock, flags);
658 }
659 
660 static void vgacon_cursor(struct vc_data *c, int mode)
661 {
662 	vgacon_restore_screen(c);
663 
664 	switch (mode) {
665 	case CM_ERASE:
666 		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
667 	        if (vga_video_type >= VIDEO_TYPE_VGAC)
668 			vgacon_set_cursor_size(c->vc_x, 31, 30);
669 		else
670 			vgacon_set_cursor_size(c->vc_x, 31, 31);
671 		break;
672 
673 	case CM_MOVE:
674 	case CM_DRAW:
675 		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
676 		switch (c->vc_cursor_type & 0x0f) {
677 		case CUR_UNDERLINE:
678 			vgacon_set_cursor_size(c->vc_x,
679 					       c->vc_font.height -
680 					       (c->vc_font.height <
681 						10 ? 2 : 3),
682 					       c->vc_font.height -
683 					       (c->vc_font.height <
684 						10 ? 1 : 2));
685 			break;
686 		case CUR_TWO_THIRDS:
687 			vgacon_set_cursor_size(c->vc_x,
688 					       c->vc_font.height / 3,
689 					       c->vc_font.height -
690 					       (c->vc_font.height <
691 						10 ? 1 : 2));
692 			break;
693 		case CUR_LOWER_THIRD:
694 			vgacon_set_cursor_size(c->vc_x,
695 					       (c->vc_font.height * 2) / 3,
696 					       c->vc_font.height -
697 					       (c->vc_font.height <
698 						10 ? 1 : 2));
699 			break;
700 		case CUR_LOWER_HALF:
701 			vgacon_set_cursor_size(c->vc_x,
702 					       c->vc_font.height / 2,
703 					       c->vc_font.height -
704 					       (c->vc_font.height <
705 						10 ? 1 : 2));
706 			break;
707 		case CUR_NONE:
708 			if (vga_video_type >= VIDEO_TYPE_VGAC)
709 				vgacon_set_cursor_size(c->vc_x, 31, 30);
710 			else
711 				vgacon_set_cursor_size(c->vc_x, 31, 31);
712 			break;
713 		default:
714 			vgacon_set_cursor_size(c->vc_x, 1,
715 					       c->vc_font.height);
716 			break;
717 		}
718 		break;
719 	}
720 }
721 
722 static int vgacon_doresize(struct vc_data *c,
723 		unsigned int width, unsigned int height)
724 {
725 	unsigned long flags;
726 	unsigned int scanlines = height * c->vc_font.height;
727 	u8 scanlines_lo = 0, r7 = 0, vsync_end = 0, mode, max_scan;
728 
729 	spin_lock_irqsave(&vga_lock, flags);
730 
731 	vgacon_xres = width * VGA_FONTWIDTH;
732 	vgacon_yres = height * c->vc_font.height;
733 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
734 		outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
735 		max_scan = inb_p(vga_video_port_val);
736 
737 		if (max_scan & 0x80)
738 			scanlines <<= 1;
739 
740 		outb_p(VGA_CRTC_MODE, vga_video_port_reg);
741 		mode = inb_p(vga_video_port_val);
742 
743 		if (mode & 0x04)
744 			scanlines >>= 1;
745 
746 		scanlines -= 1;
747 		scanlines_lo = scanlines & 0xff;
748 
749 		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
750 		r7 = inb_p(vga_video_port_val) & ~0x42;
751 
752 		if (scanlines & 0x100)
753 			r7 |= 0x02;
754 		if (scanlines & 0x200)
755 			r7 |= 0x40;
756 
757 		/* deprotect registers */
758 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
759 		vsync_end = inb_p(vga_video_port_val);
760 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
761 		outb_p(vsync_end & ~0x80, vga_video_port_val);
762 	}
763 
764 	outb_p(VGA_CRTC_H_DISP, vga_video_port_reg);
765 	outb_p(width - 1, vga_video_port_val);
766 	outb_p(VGA_CRTC_OFFSET, vga_video_port_reg);
767 	outb_p(width >> 1, vga_video_port_val);
768 
769 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
770 		outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
771 		outb_p(scanlines_lo, vga_video_port_val);
772 		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
773 		outb_p(r7,vga_video_port_val);
774 
775 		/* reprotect registers */
776 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
777 		outb_p(vsync_end, vga_video_port_val);
778 	}
779 
780 	spin_unlock_irqrestore(&vga_lock, flags);
781 	return 0;
782 }
783 
784 static int vgacon_switch(struct vc_data *c)
785 {
786 	int x = c->vc_cols * VGA_FONTWIDTH;
787 	int y = c->vc_rows * c->vc_font.height;
788 	int rows = ORIG_VIDEO_LINES * vga_default_font_height/
789 		c->vc_font.height;
790 	/*
791 	 * We need to save screen size here as it's the only way
792 	 * we can spot the screen has been resized and we need to
793 	 * set size of freshly allocated screens ourselves.
794 	 */
795 	vga_video_num_columns = c->vc_cols;
796 	vga_video_num_lines = c->vc_rows;
797 
798 	/* We can only copy out the size of the video buffer here,
799 	 * otherwise we get into VGA BIOS */
800 
801 	if (!vga_is_gfx) {
802 		scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
803 			    c->vc_screenbuf_size > vga_vram_size ?
804 				vga_vram_size : c->vc_screenbuf_size);
805 
806 		if ((vgacon_xres != x || vgacon_yres != y) &&
807 		    (!(vga_video_num_columns % 2) &&
808 		     vga_video_num_columns <= ORIG_VIDEO_COLS &&
809 		     vga_video_num_lines <= rows))
810 			vgacon_doresize(c, c->vc_cols, c->vc_rows);
811 	}
812 
813 	vgacon_scrollback_init(c->vc_size_row);
814 	return 0;		/* Redrawing not needed */
815 }
816 
817 static void vga_set_palette(struct vc_data *vc, unsigned char *table)
818 {
819 	int i, j;
820 
821 	vga_w(state.vgabase, VGA_PEL_MSK, 0xff);
822 	for (i = j = 0; i < 16; i++) {
823 		vga_w(state.vgabase, VGA_PEL_IW, table[i]);
824 		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
825 		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
826 		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
827 	}
828 }
829 
830 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table)
831 {
832 #ifdef CAN_LOAD_PALETTE
833 	if (vga_video_type != VIDEO_TYPE_VGAC || vga_palette_blanked
834 	    || !CON_IS_VISIBLE(vc))
835 		return -EINVAL;
836 	vga_set_palette(vc, table);
837 	return 0;
838 #else
839 	return -EINVAL;
840 #endif
841 }
842 
843 /* structure holding original VGA register settings */
844 static struct {
845 	unsigned char SeqCtrlIndex;	/* Sequencer Index reg.   */
846 	unsigned char CrtCtrlIndex;	/* CRT-Contr. Index reg.  */
847 	unsigned char CrtMiscIO;	/* Miscellaneous register */
848 	unsigned char HorizontalTotal;	/* CRT-Controller:00h */
849 	unsigned char HorizDisplayEnd;	/* CRT-Controller:01h */
850 	unsigned char StartHorizRetrace;	/* CRT-Controller:04h */
851 	unsigned char EndHorizRetrace;	/* CRT-Controller:05h */
852 	unsigned char Overflow;	/* CRT-Controller:07h */
853 	unsigned char StartVertRetrace;	/* CRT-Controller:10h */
854 	unsigned char EndVertRetrace;	/* CRT-Controller:11h */
855 	unsigned char ModeControl;	/* CRT-Controller:17h */
856 	unsigned char ClockingMode;	/* Seq-Controller:01h */
857 } vga_state;
858 
859 static void vga_vesa_blank(struct vgastate *state, int mode)
860 {
861 	/* save original values of VGA controller registers */
862 	if (!vga_vesa_blanked) {
863 		spin_lock_irq(&vga_lock);
864 		vga_state.SeqCtrlIndex = vga_r(state->vgabase, VGA_SEQ_I);
865 		vga_state.CrtCtrlIndex = inb_p(vga_video_port_reg);
866 		vga_state.CrtMiscIO = vga_r(state->vgabase, VGA_MIS_R);
867 		spin_unlock_irq(&vga_lock);
868 
869 		outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
870 		vga_state.HorizontalTotal = inb_p(vga_video_port_val);
871 		outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
872 		vga_state.HorizDisplayEnd = inb_p(vga_video_port_val);
873 		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
874 		vga_state.StartHorizRetrace = inb_p(vga_video_port_val);
875 		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
876 		vga_state.EndHorizRetrace = inb_p(vga_video_port_val);
877 		outb_p(0x07, vga_video_port_reg);	/* Overflow */
878 		vga_state.Overflow = inb_p(vga_video_port_val);
879 		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
880 		vga_state.StartVertRetrace = inb_p(vga_video_port_val);
881 		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
882 		vga_state.EndVertRetrace = inb_p(vga_video_port_val);
883 		outb_p(0x17, vga_video_port_reg);	/* ModeControl */
884 		vga_state.ModeControl = inb_p(vga_video_port_val);
885 		vga_state.ClockingMode = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
886 	}
887 
888 	/* assure that video is enabled */
889 	/* "0x20" is VIDEO_ENABLE_bit in register 01 of sequencer */
890 	spin_lock_irq(&vga_lock);
891 	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode | 0x20);
892 
893 	/* test for vertical retrace in process.... */
894 	if ((vga_state.CrtMiscIO & 0x80) == 0x80)
895 		vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO & 0xEF);
896 
897 	/*
898 	 * Set <End of vertical retrace> to minimum (0) and
899 	 * <Start of vertical Retrace> to maximum (incl. overflow)
900 	 * Result: turn off vertical sync (VSync) pulse.
901 	 */
902 	if (mode & VESA_VSYNC_SUSPEND) {
903 		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
904 		outb_p(0xff, vga_video_port_val);	/* maximum value */
905 		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
906 		outb_p(0x40, vga_video_port_val);	/* minimum (bits 0..3)  */
907 		outb_p(0x07, vga_video_port_reg);	/* Overflow */
908 		outb_p(vga_state.Overflow | 0x84, vga_video_port_val);	/* bits 9,10 of vert. retrace */
909 	}
910 
911 	if (mode & VESA_HSYNC_SUSPEND) {
912 		/*
913 		 * Set <End of horizontal retrace> to minimum (0) and
914 		 *  <Start of horizontal Retrace> to maximum
915 		 * Result: turn off horizontal sync (HSync) pulse.
916 		 */
917 		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
918 		outb_p(0xff, vga_video_port_val);	/* maximum */
919 		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
920 		outb_p(0x00, vga_video_port_val);	/* minimum (0) */
921 	}
922 
923 	/* restore both index registers */
924 	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
925 	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
926 	spin_unlock_irq(&vga_lock);
927 }
928 
929 static void vga_vesa_unblank(struct vgastate *state)
930 {
931 	/* restore original values of VGA controller registers */
932 	spin_lock_irq(&vga_lock);
933 	vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO);
934 
935 	outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
936 	outb_p(vga_state.HorizontalTotal, vga_video_port_val);
937 	outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
938 	outb_p(vga_state.HorizDisplayEnd, vga_video_port_val);
939 	outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
940 	outb_p(vga_state.StartHorizRetrace, vga_video_port_val);
941 	outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
942 	outb_p(vga_state.EndHorizRetrace, vga_video_port_val);
943 	outb_p(0x07, vga_video_port_reg);	/* Overflow */
944 	outb_p(vga_state.Overflow, vga_video_port_val);
945 	outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
946 	outb_p(vga_state.StartVertRetrace, vga_video_port_val);
947 	outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
948 	outb_p(vga_state.EndVertRetrace, vga_video_port_val);
949 	outb_p(0x17, vga_video_port_reg);	/* ModeControl */
950 	outb_p(vga_state.ModeControl, vga_video_port_val);
951 	/* ClockingMode */
952 	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode);
953 
954 	/* restore index/control registers */
955 	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
956 	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
957 	spin_unlock_irq(&vga_lock);
958 }
959 
960 static void vga_pal_blank(struct vgastate *state)
961 {
962 	int i;
963 
964 	vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
965 	for (i = 0; i < 16; i++) {
966 		vga_w(state->vgabase, VGA_PEL_IW, i);
967 		vga_w(state->vgabase, VGA_PEL_D, 0);
968 		vga_w(state->vgabase, VGA_PEL_D, 0);
969 		vga_w(state->vgabase, VGA_PEL_D, 0);
970 	}
971 }
972 
973 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch)
974 {
975 	switch (blank) {
976 	case 0:		/* Unblank */
977 		if (vga_vesa_blanked) {
978 			vga_vesa_unblank(&state);
979 			vga_vesa_blanked = 0;
980 		}
981 		if (vga_palette_blanked) {
982 			vga_set_palette(c, color_table);
983 			vga_palette_blanked = 0;
984 			return 0;
985 		}
986 		vga_is_gfx = 0;
987 		/* Tell console.c that it has to restore the screen itself */
988 		return 1;
989 	case 1:		/* Normal blanking */
990 	case -1:	/* Obsolete */
991 		if (!mode_switch && vga_video_type == VIDEO_TYPE_VGAC) {
992 			vga_pal_blank(&state);
993 			vga_palette_blanked = 1;
994 			return 0;
995 		}
996 		vgacon_set_origin(c);
997 		scr_memsetw((void *) vga_vram_base, BLANK,
998 			    c->vc_screenbuf_size);
999 		if (mode_switch)
1000 			vga_is_gfx = 1;
1001 		return 1;
1002 	default:		/* VESA blanking */
1003 		if (vga_video_type == VIDEO_TYPE_VGAC) {
1004 			vga_vesa_blank(&state, blank - 1);
1005 			vga_vesa_blanked = blank;
1006 		}
1007 		return 0;
1008 	}
1009 }
1010 
1011 /*
1012  * PIO_FONT support.
1013  *
1014  * The font loading code goes back to the codepage package by
1015  * Joel Hoffman (joel@wam.umd.edu). (He reports that the original
1016  * reference is: "From: p. 307 of _Programmer's Guide to PC & PS/2
1017  * Video Systems_ by Richard Wilton. 1987.  Microsoft Press".)
1018  *
1019  * Change for certain monochrome monitors by Yury Shevchuck
1020  * (sizif@botik.yaroslavl.su).
1021  */
1022 
1023 #ifdef CAN_LOAD_EGA_FONTS
1024 
1025 #define colourmap 0xa0000
1026 /* Pauline Middelink <middelin@polyware.iaf.nl> reports that we
1027    should use 0xA0000 for the bwmap as well.. */
1028 #define blackwmap 0xa0000
1029 #define cmapsz 8192
1030 
1031 static int vgacon_do_font_op(struct vgastate *state,char *arg,int set,int ch512)
1032 {
1033 	unsigned short video_port_status = vga_video_port_reg + 6;
1034 	int font_select = 0x00, beg, i;
1035 	char *charmap;
1036 
1037 	if (vga_video_type != VIDEO_TYPE_EGAM) {
1038 		charmap = (char *) VGA_MAP_MEM(colourmap, 0);
1039 		beg = 0x0e;
1040 #ifdef VGA_CAN_DO_64KB
1041 		if (vga_video_type == VIDEO_TYPE_VGAC)
1042 			beg = 0x06;
1043 #endif
1044 	} else {
1045 		charmap = (char *) VGA_MAP_MEM(blackwmap, 0);
1046 		beg = 0x0a;
1047 	}
1048 
1049 #ifdef BROKEN_GRAPHICS_PROGRAMS
1050 	/*
1051 	 * All fonts are loaded in slot 0 (0:1 for 512 ch)
1052 	 */
1053 
1054 	if (!arg)
1055 		return -EINVAL;	/* Return to default font not supported */
1056 
1057 	vga_font_is_default = 0;
1058 	font_select = ch512 ? 0x04 : 0x00;
1059 #else
1060 	/*
1061 	 * The default font is kept in slot 0 and is never touched.
1062 	 * A custom font is loaded in slot 2 (256 ch) or 2:3 (512 ch)
1063 	 */
1064 
1065 	if (set) {
1066 		vga_font_is_default = !arg;
1067 		if (!arg)
1068 			ch512 = 0;	/* Default font is always 256 */
1069 		font_select = arg ? (ch512 ? 0x0e : 0x0a) : 0x00;
1070 	}
1071 
1072 	if (!vga_font_is_default)
1073 		charmap += 4 * cmapsz;
1074 #endif
1075 
1076 	unlock_kernel();
1077 	spin_lock_irq(&vga_lock);
1078 	/* First, the Sequencer */
1079 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
1080 	/* CPU writes only to map 2 */
1081 	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x04);
1082 	/* Sequential addressing */
1083 	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x07);
1084 	/* Clear synchronous reset */
1085 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
1086 
1087 	/* Now, the graphics controller, select map 2 */
1088 	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x02);
1089 	/* disable odd-even addressing */
1090 	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x00);
1091 	/* map start at A000:0000 */
1092 	vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x00);
1093 	spin_unlock_irq(&vga_lock);
1094 
1095 	if (arg) {
1096 		if (set)
1097 			for (i = 0; i < cmapsz; i++)
1098 				vga_writeb(arg[i], charmap + i);
1099 		else
1100 			for (i = 0; i < cmapsz; i++)
1101 				arg[i] = vga_readb(charmap + i);
1102 
1103 		/*
1104 		 * In 512-character mode, the character map is not contiguous if
1105 		 * we want to remain EGA compatible -- which we do
1106 		 */
1107 
1108 		if (ch512) {
1109 			charmap += 2 * cmapsz;
1110 			arg += cmapsz;
1111 			if (set)
1112 				for (i = 0; i < cmapsz; i++)
1113 					vga_writeb(arg[i], charmap + i);
1114 			else
1115 				for (i = 0; i < cmapsz; i++)
1116 					arg[i] = vga_readb(charmap + i);
1117 		}
1118 	}
1119 
1120 	spin_lock_irq(&vga_lock);
1121 	/* First, the sequencer, Synchronous reset */
1122 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);
1123 	/* CPU writes to maps 0 and 1 */
1124 	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x03);
1125 	/* odd-even addressing */
1126 	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x03);
1127 	/* Character Map Select */
1128 	if (set)
1129 		vga_wseq(state->vgabase, VGA_SEQ_CHARACTER_MAP, font_select);
1130 	/* clear synchronous reset */
1131 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
1132 
1133 	/* Now, the graphics controller, select map 0 for CPU */
1134 	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x00);
1135 	/* enable even-odd addressing */
1136 	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x10);
1137 	/* map starts at b800:0 or b000:0 */
1138 	vga_wgfx(state->vgabase, VGA_GFX_MISC, beg);
1139 
1140 	/* if 512 char mode is already enabled don't re-enable it. */
1141 	if ((set) && (ch512 != vga_512_chars)) {
1142 		int i;
1143 
1144 		/* attribute controller */
1145 		for (i = 0; i < MAX_NR_CONSOLES; i++) {
1146 			struct vc_data *c = vc_cons[i].d;
1147 			if (c && c->vc_sw == &vga_con)
1148 				c->vc_hi_font_mask = ch512 ? 0x0800 : 0;
1149 		}
1150 		vga_512_chars = ch512;
1151 		/* 256-char: enable intensity bit
1152 		   512-char: disable intensity bit */
1153 		inb_p(video_port_status);	/* clear address flip-flop */
1154 		/* color plane enable register */
1155 		vga_wattr(state->vgabase, VGA_ATC_PLANE_ENABLE, ch512 ? 0x07 : 0x0f);
1156 		/* Wilton (1987) mentions the following; I don't know what
1157 		   it means, but it works, and it appears necessary */
1158 		inb_p(video_port_status);
1159 		vga_wattr(state->vgabase, VGA_AR_ENABLE_DISPLAY, 0);
1160 	}
1161 	spin_unlock_irq(&vga_lock);
1162 	lock_kernel();
1163 	return 0;
1164 }
1165 
1166 /*
1167  * Adjust the screen to fit a font of a certain height
1168  */
1169 static int vgacon_adjust_height(struct vc_data *vc, unsigned fontheight)
1170 {
1171 	unsigned char ovr, vde, fsr;
1172 	int rows, maxscan, i;
1173 
1174 	rows = vc->vc_scan_lines / fontheight;	/* Number of video rows we end up with */
1175 	maxscan = rows * fontheight - 1;	/* Scan lines to actually display-1 */
1176 
1177 	/* Reprogram the CRTC for the new font size
1178 	   Note: the attempt to read the overflow register will fail
1179 	   on an EGA, but using 0xff for the previous value appears to
1180 	   be OK for EGA text modes in the range 257-512 scan lines, so I
1181 	   guess we don't need to worry about it.
1182 
1183 	   The same applies for the spill bits in the font size and cursor
1184 	   registers; they are write-only on EGA, but it appears that they
1185 	   are all don't care bits on EGA, so I guess it doesn't matter. */
1186 
1187 	spin_lock_irq(&vga_lock);
1188 	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
1189 	ovr = inb_p(vga_video_port_val);
1190 	outb_p(0x09, vga_video_port_reg);	/* Font size register */
1191 	fsr = inb_p(vga_video_port_val);
1192 	spin_unlock_irq(&vga_lock);
1193 
1194 	vde = maxscan & 0xff;	/* Vertical display end reg */
1195 	ovr = (ovr & 0xbd) +	/* Overflow register */
1196 	    ((maxscan & 0x100) >> 7) + ((maxscan & 0x200) >> 3);
1197 	fsr = (fsr & 0xe0) + (fontheight - 1);	/*  Font size register */
1198 
1199 	spin_lock_irq(&vga_lock);
1200 	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
1201 	outb_p(ovr, vga_video_port_val);
1202 	outb_p(0x09, vga_video_port_reg);	/* Font size */
1203 	outb_p(fsr, vga_video_port_val);
1204 	outb_p(0x12, vga_video_port_reg);	/* Vertical display limit */
1205 	outb_p(vde, vga_video_port_val);
1206 	spin_unlock_irq(&vga_lock);
1207 	vga_video_font_height = fontheight;
1208 
1209 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
1210 		struct vc_data *c = vc_cons[i].d;
1211 
1212 		if (c && c->vc_sw == &vga_con) {
1213 			if (CON_IS_VISIBLE(c)) {
1214 			        /* void size to cause regs to be rewritten */
1215 				cursor_size_lastfrom = 0;
1216 				cursor_size_lastto = 0;
1217 				c->vc_sw->con_cursor(c, CM_DRAW);
1218 			}
1219 			c->vc_font.height = fontheight;
1220 			vc_resize(c, 0, rows);	/* Adjust console size */
1221 		}
1222 	}
1223 	return 0;
1224 }
1225 
1226 static int vgacon_font_set(struct vc_data *c, struct console_font *font, unsigned flags)
1227 {
1228 	unsigned charcount = font->charcount;
1229 	int rc;
1230 
1231 	if (vga_video_type < VIDEO_TYPE_EGAM)
1232 		return -EINVAL;
1233 
1234 	if (font->width != VGA_FONTWIDTH ||
1235 	    (charcount != 256 && charcount != 512))
1236 		return -EINVAL;
1237 
1238 	rc = vgacon_do_font_op(&state, font->data, 1, charcount == 512);
1239 	if (rc)
1240 		return rc;
1241 
1242 	if (!(flags & KD_FONT_FLAG_DONT_RECALC))
1243 		rc = vgacon_adjust_height(c, font->height);
1244 	return rc;
1245 }
1246 
1247 static int vgacon_font_get(struct vc_data *c, struct console_font *font)
1248 {
1249 	if (vga_video_type < VIDEO_TYPE_EGAM)
1250 		return -EINVAL;
1251 
1252 	font->width = VGA_FONTWIDTH;
1253 	font->height = c->vc_font.height;
1254 	font->charcount = vga_512_chars ? 512 : 256;
1255 	if (!font->data)
1256 		return 0;
1257 	return vgacon_do_font_op(&state, font->data, 0, 0);
1258 }
1259 
1260 #else
1261 
1262 #define vgacon_font_set NULL
1263 #define vgacon_font_get NULL
1264 
1265 #endif
1266 
1267 static int vgacon_resize(struct vc_data *c, unsigned int width,
1268 				unsigned int height)
1269 {
1270 	if (width % 2 || width > ORIG_VIDEO_COLS ||
1271 	    height > (ORIG_VIDEO_LINES * vga_default_font_height)/
1272 	    c->vc_font.height)
1273 		/* let svgatextmode tinker with video timings */
1274 		return 0;
1275 
1276 	if (CON_IS_VISIBLE(c) && !vga_is_gfx) /* who knows */
1277 		vgacon_doresize(c, width, height);
1278 	return 0;
1279 }
1280 
1281 static int vgacon_set_origin(struct vc_data *c)
1282 {
1283 	if (vga_is_gfx ||	/* We don't play origin tricks in graphic modes */
1284 	    (console_blanked && !vga_palette_blanked))	/* Nor we write to blanked screens */
1285 		return 0;
1286 	c->vc_origin = c->vc_visible_origin = vga_vram_base;
1287 	vga_set_mem_top(c);
1288 	vga_rolled_over = 0;
1289 	return 1;
1290 }
1291 
1292 static void vgacon_save_screen(struct vc_data *c)
1293 {
1294 	static int vga_bootup_console = 0;
1295 
1296 	if (!vga_bootup_console) {
1297 		/* This is a gross hack, but here is the only place we can
1298 		 * set bootup console parameters without messing up generic
1299 		 * console initialization routines.
1300 		 */
1301 		vga_bootup_console = 1;
1302 		c->vc_x = ORIG_X;
1303 		c->vc_y = ORIG_Y;
1304 	}
1305 
1306 	/* We can't copy in more then the size of the video buffer,
1307 	 * or we'll be copying in VGA BIOS */
1308 
1309 	if (!vga_is_gfx)
1310 		scr_memcpyw((u16 *) c->vc_screenbuf, (u16 *) c->vc_origin,
1311 			    c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size);
1312 }
1313 
1314 static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
1315 			 int lines)
1316 {
1317 	unsigned long oldo;
1318 	unsigned int delta;
1319 
1320 	if (t || b != c->vc_rows || vga_is_gfx)
1321 		return 0;
1322 
1323 	if (!vga_hardscroll_enabled || lines >= c->vc_rows / 2)
1324 		return 0;
1325 
1326 	vgacon_restore_screen(c);
1327 	oldo = c->vc_origin;
1328 	delta = lines * c->vc_size_row;
1329 	if (dir == SM_UP) {
1330 		vgacon_scrollback_update(c, t, lines);
1331 		if (c->vc_scr_end + delta >= vga_vram_end) {
1332 			scr_memcpyw((u16 *) vga_vram_base,
1333 				    (u16 *) (oldo + delta),
1334 				    c->vc_screenbuf_size - delta);
1335 			c->vc_origin = vga_vram_base;
1336 			vga_rolled_over = oldo - vga_vram_base;
1337 		} else
1338 			c->vc_origin += delta;
1339 		scr_memsetw((u16 *) (c->vc_origin + c->vc_screenbuf_size -
1340 				     delta), c->vc_video_erase_char,
1341 			    delta);
1342 	} else {
1343 		if (oldo - delta < vga_vram_base) {
1344 			scr_memmovew((u16 *) (vga_vram_end -
1345 					      c->vc_screenbuf_size +
1346 					      delta), (u16 *) oldo,
1347 				     c->vc_screenbuf_size - delta);
1348 			c->vc_origin = vga_vram_end - c->vc_screenbuf_size;
1349 			vga_rolled_over = 0;
1350 		} else
1351 			c->vc_origin -= delta;
1352 		c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1353 		scr_memsetw((u16 *) (c->vc_origin), c->vc_video_erase_char,
1354 			    delta);
1355 	}
1356 	c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1357 	c->vc_visible_origin = c->vc_origin;
1358 	vga_set_mem_top(c);
1359 	c->vc_pos = (c->vc_pos - oldo) + c->vc_origin;
1360 	return 1;
1361 }
1362 
1363 
1364 /*
1365  *  The console `switch' structure for the VGA based console
1366  */
1367 
1368 static int vgacon_dummy(struct vc_data *c)
1369 {
1370 	return 0;
1371 }
1372 
1373 #define DUMMY (void *) vgacon_dummy
1374 
1375 const struct consw vga_con = {
1376 	.owner = THIS_MODULE,
1377 	.con_startup = vgacon_startup,
1378 	.con_init = vgacon_init,
1379 	.con_deinit = vgacon_deinit,
1380 	.con_clear = DUMMY,
1381 	.con_putc = DUMMY,
1382 	.con_putcs = DUMMY,
1383 	.con_cursor = vgacon_cursor,
1384 	.con_scroll = vgacon_scroll,
1385 	.con_bmove = DUMMY,
1386 	.con_switch = vgacon_switch,
1387 	.con_blank = vgacon_blank,
1388 	.con_font_set = vgacon_font_set,
1389 	.con_font_get = vgacon_font_get,
1390 	.con_resize = vgacon_resize,
1391 	.con_set_palette = vgacon_set_palette,
1392 	.con_scrolldelta = vgacon_scrolldelta,
1393 	.con_set_origin = vgacon_set_origin,
1394 	.con_save_screen = vgacon_save_screen,
1395 	.con_build_attr = vgacon_build_attr,
1396 	.con_invert_region = vgacon_invert_region,
1397 };
1398 
1399 MODULE_LICENSE("GPL");
1400