xref: /openbmc/linux/drivers/video/console/vgacon.c (revision 384740dc)
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/module.h>
37 #include <linux/types.h>
38 #include <linux/fs.h>
39 #include <linux/kernel.h>
40 #include <linux/console.h>
41 #include <linux/string.h>
42 #include <linux/kd.h>
43 #include <linux/slab.h>
44 #include <linux/vt_kern.h>
45 #include <linux/selection.h>
46 #include <linux/spinlock.h>
47 #include <linux/ioport.h>
48 #include <linux/init.h>
49 #include <linux/screen_info.h>
50 #include <linux/smp_lock.h>
51 #include <video/vga.h>
52 #include <asm/io.h>
53 
54 static DEFINE_SPINLOCK(vga_lock);
55 static int cursor_size_lastfrom;
56 static int cursor_size_lastto;
57 static u32 vgacon_xres;
58 static u32 vgacon_yres;
59 static struct vgastate state;
60 
61 #define BLANK 0x0020
62 
63 #define CAN_LOAD_EGA_FONTS	/* undefine if the user must not do this */
64 #define CAN_LOAD_PALETTE	/* undefine if the user must not do this */
65 
66 /* You really do _NOT_ want to define this, unless you have buggy
67  * Trident VGA which will resize cursor when moving it between column
68  * 15 & 16. If you define this and your VGA is OK, inverse bug will
69  * appear.
70  */
71 #undef TRIDENT_GLITCH
72 #define VGA_FONTWIDTH       8   /* VGA does not support fontwidths != 8 */
73 /*
74  *  Interface used by the world
75  */
76 
77 static const char *vgacon_startup(void);
78 static void vgacon_init(struct vc_data *c, int init);
79 static void vgacon_deinit(struct vc_data *c);
80 static void vgacon_cursor(struct vc_data *c, int mode);
81 static int vgacon_switch(struct vc_data *c);
82 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch);
83 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table);
84 static int vgacon_scrolldelta(struct vc_data *c, int lines);
85 static int vgacon_set_origin(struct vc_data *c);
86 static void vgacon_save_screen(struct vc_data *c);
87 static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
88 			 int lines);
89 static void vgacon_invert_region(struct vc_data *c, u16 * p, int count);
90 static unsigned long vgacon_uni_pagedir[2];
91 
92 /* Description of the hardware situation */
93 static int		vga_init_done		__read_mostly;
94 static unsigned long	vga_vram_base		__read_mostly;	/* Base of video memory */
95 static unsigned long	vga_vram_end		__read_mostly;	/* End of video memory */
96 static unsigned int	vga_vram_size		__read_mostly;	/* Size of video memory */
97 static u16		vga_video_port_reg	__read_mostly;	/* Video register select port */
98 static u16		vga_video_port_val	__read_mostly;	/* Video register value port */
99 static unsigned int	vga_video_num_columns;			/* Number of text columns */
100 static unsigned int	vga_video_num_lines;			/* Number of text lines */
101 static int		vga_can_do_color	__read_mostly;	/* Do we support colors? */
102 static unsigned int	vga_default_font_height __read_mostly;	/* Height of default screen font */
103 static unsigned char	vga_video_type		__read_mostly;	/* Card type */
104 static unsigned char	vga_hardscroll_enabled	__read_mostly;
105 static unsigned char	vga_hardscroll_user_enable __read_mostly = 1;
106 static unsigned char	vga_font_is_default = 1;
107 static int		vga_vesa_blanked;
108 static int 		vga_palette_blanked;
109 static int 		vga_is_gfx;
110 static int 		vga_512_chars;
111 static int 		vga_video_font_height;
112 static int 		vga_scan_lines		__read_mostly;
113 static unsigned int 	vga_rolled_over;
114 
115 static int __init no_scroll(char *str)
116 {
117 	/*
118 	 * Disabling scrollback is required for the Braillex ib80-piezo
119 	 * Braille reader made by F.H. Papenmeier (Germany).
120 	 * Use the "no-scroll" bootflag.
121 	 */
122 	vga_hardscroll_user_enable = vga_hardscroll_enabled = 0;
123 	return 1;
124 }
125 
126 __setup("no-scroll", no_scroll);
127 
128 /*
129  * By replacing the four outb_p with two back to back outw, we can reduce
130  * the window of opportunity to see text mislocated to the RHS of the
131  * console during heavy scrolling activity. However there is the remote
132  * possibility that some pre-dinosaur hardware won't like the back to back
133  * I/O. Since the Xservers get away with it, we should be able to as well.
134  */
135 static inline void write_vga(unsigned char reg, unsigned int val)
136 {
137 	unsigned int v1, v2;
138 	unsigned long flags;
139 
140 	/*
141 	 * ddprintk might set the console position from interrupt
142 	 * handlers, thus the write has to be IRQ-atomic.
143 	 */
144 	spin_lock_irqsave(&vga_lock, flags);
145 
146 #ifndef SLOW_VGA
147 	v1 = reg + (val & 0xff00);
148 	v2 = reg + 1 + ((val << 8) & 0xff00);
149 	outw(v1, vga_video_port_reg);
150 	outw(v2, vga_video_port_reg);
151 #else
152 	outb_p(reg, vga_video_port_reg);
153 	outb_p(val >> 8, vga_video_port_val);
154 	outb_p(reg + 1, vga_video_port_reg);
155 	outb_p(val & 0xff, vga_video_port_val);
156 #endif
157 	spin_unlock_irqrestore(&vga_lock, flags);
158 }
159 
160 static inline void vga_set_mem_top(struct vc_data *c)
161 {
162 	write_vga(12, (c->vc_visible_origin - vga_vram_base) / 2);
163 }
164 
165 #ifdef CONFIG_VGACON_SOFT_SCROLLBACK
166 #include <linux/bootmem.h>
167 /* software scrollback */
168 static void *vgacon_scrollback;
169 static int vgacon_scrollback_tail;
170 static int vgacon_scrollback_size;
171 static int vgacon_scrollback_rows;
172 static int vgacon_scrollback_cnt;
173 static int vgacon_scrollback_cur;
174 static int vgacon_scrollback_save;
175 static int vgacon_scrollback_restore;
176 
177 static void vgacon_scrollback_init(int pitch)
178 {
179 	int rows = CONFIG_VGACON_SOFT_SCROLLBACK_SIZE * 1024/pitch;
180 
181 	if (vgacon_scrollback) {
182 		vgacon_scrollback_cnt  = 0;
183 		vgacon_scrollback_tail = 0;
184 		vgacon_scrollback_cur  = 0;
185 		vgacon_scrollback_rows = rows - 1;
186 		vgacon_scrollback_size = rows * pitch;
187 	}
188 }
189 
190 /*
191  * Called only duing init so call of alloc_bootmen is ok.
192  * Marked __init_refok to silence modpost.
193  */
194 static void __init_refok 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 (screen_info.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 	/* boot_params.screen_info initialized? */
376 	if ((screen_info.orig_video_mode  == 0) &&
377 	    (screen_info.orig_video_lines == 0) &&
378 	    (screen_info.orig_video_cols  == 0))
379 		goto no_vga;
380 
381 	/* VGA16 modes are not handled by VGACON */
382 	if ((screen_info.orig_video_mode == 0x0D) ||	/* 320x200/4 */
383 	    (screen_info.orig_video_mode == 0x0E) ||	/* 640x200/4 */
384 	    (screen_info.orig_video_mode == 0x10) ||	/* 640x350/4 */
385 	    (screen_info.orig_video_mode == 0x12) ||	/* 640x480/4 */
386 	    (screen_info.orig_video_mode == 0x6A))	/* 800x600/4 (VESA) */
387 		goto no_vga;
388 
389 	vga_video_num_lines = screen_info.orig_video_lines;
390 	vga_video_num_columns = screen_info.orig_video_cols;
391 	state.vgabase = NULL;
392 
393 	if (screen_info.orig_video_mode == 7) {
394 		/* Monochrome display */
395 		vga_vram_base = 0xb0000;
396 		vga_video_port_reg = VGA_CRT_IM;
397 		vga_video_port_val = VGA_CRT_DM;
398 		if ((screen_info.orig_video_ega_bx & 0xff) != 0x10) {
399 			static struct resource ega_console_resource =
400 			    { .name = "ega", .start = 0x3B0, .end = 0x3BF };
401 			vga_video_type = VIDEO_TYPE_EGAM;
402 			vga_vram_size = 0x8000;
403 			display_desc = "EGA+";
404 			request_resource(&ioport_resource,
405 					 &ega_console_resource);
406 		} else {
407 			static struct resource mda1_console_resource =
408 			    { .name = "mda", .start = 0x3B0, .end = 0x3BB };
409 			static struct resource mda2_console_resource =
410 			    { .name = "mda", .start = 0x3BF, .end = 0x3BF };
411 			vga_video_type = VIDEO_TYPE_MDA;
412 			vga_vram_size = 0x2000;
413 			display_desc = "*MDA";
414 			request_resource(&ioport_resource,
415 					 &mda1_console_resource);
416 			request_resource(&ioport_resource,
417 					 &mda2_console_resource);
418 			vga_video_font_height = 14;
419 		}
420 	} else {
421 		/* If not, it is color. */
422 		vga_can_do_color = 1;
423 		vga_vram_base = 0xb8000;
424 		vga_video_port_reg = VGA_CRT_IC;
425 		vga_video_port_val = VGA_CRT_DC;
426 		if ((screen_info.orig_video_ega_bx & 0xff) != 0x10) {
427 			int i;
428 
429 			vga_vram_size = 0x8000;
430 
431 			if (!screen_info.orig_video_isVGA) {
432 				static struct resource ega_console_resource
433 				    = { .name = "ega", .start = 0x3C0, .end = 0x3DF };
434 				vga_video_type = VIDEO_TYPE_EGAC;
435 				display_desc = "EGA";
436 				request_resource(&ioport_resource,
437 						 &ega_console_resource);
438 			} else {
439 				static struct resource vga_console_resource
440 				    = { .name = "vga+", .start = 0x3C0, .end = 0x3DF };
441 				vga_video_type = VIDEO_TYPE_VGAC;
442 				display_desc = "VGA+";
443 				request_resource(&ioport_resource,
444 						 &vga_console_resource);
445 
446 #ifdef VGA_CAN_DO_64KB
447 				/*
448 				 * get 64K rather than 32K of video RAM.
449 				 * This doesn't actually work on all "VGA"
450 				 * controllers (it seems like setting MM=01
451 				 * and COE=1 isn't necessarily a good idea)
452 				 */
453 				vga_vram_base = 0xa0000;
454 				vga_vram_size = 0x10000;
455 				outb_p(6, VGA_GFX_I);
456 				outb_p(6, VGA_GFX_D);
457 #endif
458 				/*
459 				 * Normalise the palette registers, to point
460 				 * the 16 screen colours to the first 16
461 				 * DAC entries.
462 				 */
463 
464 				for (i = 0; i < 16; i++) {
465 					inb_p(VGA_IS1_RC);
466 					outb_p(i, VGA_ATT_W);
467 					outb_p(i, VGA_ATT_W);
468 				}
469 				outb_p(0x20, VGA_ATT_W);
470 
471 				/*
472 				 * Now set the DAC registers back to their
473 				 * default values
474 				 */
475 				for (i = 0; i < 16; i++) {
476 					outb_p(color_table[i], VGA_PEL_IW);
477 					outb_p(default_red[i], VGA_PEL_D);
478 					outb_p(default_grn[i], VGA_PEL_D);
479 					outb_p(default_blu[i], VGA_PEL_D);
480 				}
481 			}
482 		} else {
483 			static struct resource cga_console_resource =
484 			    { .name = "cga", .start = 0x3D4, .end = 0x3D5 };
485 			vga_video_type = VIDEO_TYPE_CGA;
486 			vga_vram_size = 0x2000;
487 			display_desc = "*CGA";
488 			request_resource(&ioport_resource,
489 					 &cga_console_resource);
490 			vga_video_font_height = 8;
491 		}
492 	}
493 
494 	vga_vram_base = VGA_MAP_MEM(vga_vram_base, vga_vram_size);
495 	vga_vram_end = vga_vram_base + vga_vram_size;
496 
497 	/*
498 	 *      Find out if there is a graphics card present.
499 	 *      Are there smarter methods around?
500 	 */
501 	p = (volatile u16 *) vga_vram_base;
502 	saved1 = scr_readw(p);
503 	saved2 = scr_readw(p + 1);
504 	scr_writew(0xAA55, p);
505 	scr_writew(0x55AA, p + 1);
506 	if (scr_readw(p) != 0xAA55 || scr_readw(p + 1) != 0x55AA) {
507 		scr_writew(saved1, p);
508 		scr_writew(saved2, p + 1);
509 		goto no_vga;
510 	}
511 	scr_writew(0x55AA, p);
512 	scr_writew(0xAA55, p + 1);
513 	if (scr_readw(p) != 0x55AA || scr_readw(p + 1) != 0xAA55) {
514 		scr_writew(saved1, p);
515 		scr_writew(saved2, p + 1);
516 		goto no_vga;
517 	}
518 	scr_writew(saved1, p);
519 	scr_writew(saved2, p + 1);
520 
521 	if (vga_video_type == VIDEO_TYPE_EGAC
522 	    || vga_video_type == VIDEO_TYPE_VGAC
523 	    || vga_video_type == VIDEO_TYPE_EGAM) {
524 		vga_hardscroll_enabled = vga_hardscroll_user_enable;
525 		vga_default_font_height = screen_info.orig_video_points;
526 		vga_video_font_height = screen_info.orig_video_points;
527 		/* This may be suboptimal but is a safe bet - go with it */
528 		vga_scan_lines =
529 		    vga_video_font_height * vga_video_num_lines;
530 	}
531 
532 	vgacon_xres = screen_info.orig_video_cols * VGA_FONTWIDTH;
533 	vgacon_yres = vga_scan_lines;
534 
535 	if (!vga_init_done) {
536 		vgacon_scrollback_startup();
537 		vga_init_done = 1;
538 	}
539 
540 	return display_desc;
541 }
542 
543 static void vgacon_init(struct vc_data *c, int init)
544 {
545 	unsigned long p;
546 
547 	/*
548 	 * We cannot be loaded as a module, therefore init is always 1,
549 	 * but vgacon_init can be called more than once, and init will
550 	 * not be 1.
551 	 */
552 	c->vc_can_do_color = vga_can_do_color;
553 
554 	/* set dimensions manually if init != 0 since vc_resize() will fail */
555 	if (init) {
556 		c->vc_cols = vga_video_num_columns;
557 		c->vc_rows = vga_video_num_lines;
558 	} else
559 		vc_resize(c, vga_video_num_columns, vga_video_num_lines);
560 
561 	c->vc_scan_lines = vga_scan_lines;
562 	c->vc_font.height = vga_video_font_height;
563 	c->vc_complement_mask = 0x7700;
564 	if (vga_512_chars)
565 		c->vc_hi_font_mask = 0x0800;
566 	p = *c->vc_uni_pagedir_loc;
567 	if (c->vc_uni_pagedir_loc == &c->vc_uni_pagedir ||
568 	    !--c->vc_uni_pagedir_loc[1])
569 		con_free_unimap(c);
570 	c->vc_uni_pagedir_loc = vgacon_uni_pagedir;
571 	vgacon_uni_pagedir[1]++;
572 	if (!vgacon_uni_pagedir[0] && p)
573 		con_set_default_unimap(c);
574 }
575 
576 static void vgacon_deinit(struct vc_data *c)
577 {
578 	/* When closing the last console, reset video origin */
579 	if (!--vgacon_uni_pagedir[1]) {
580 		c->vc_visible_origin = vga_vram_base;
581 		vga_set_mem_top(c);
582 		con_free_unimap(c);
583 	}
584 	c->vc_uni_pagedir_loc = &c->vc_uni_pagedir;
585 	con_set_default_unimap(c);
586 }
587 
588 static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
589 			    u8 blink, u8 underline, u8 reverse, u8 italic)
590 {
591 	u8 attr = color;
592 
593 	if (vga_can_do_color) {
594 		if (italic)
595 			attr = (attr & 0xF0) | c->vc_itcolor;
596 		else if (underline)
597 			attr = (attr & 0xf0) | c->vc_ulcolor;
598 		else if (intensity == 0)
599 			attr = (attr & 0xf0) | c->vc_halfcolor;
600 	}
601 	if (reverse)
602 		attr =
603 		    ((attr) & 0x88) | ((((attr) >> 4) | ((attr) << 4)) &
604 				       0x77);
605 	if (blink)
606 		attr ^= 0x80;
607 	if (intensity == 2)
608 		attr ^= 0x08;
609 	if (!vga_can_do_color) {
610 		if (italic)
611 			attr = (attr & 0xF8) | 0x02;
612 		else if (underline)
613 			attr = (attr & 0xf8) | 0x01;
614 		else if (intensity == 0)
615 			attr = (attr & 0xf0) | 0x08;
616 	}
617 	return attr;
618 }
619 
620 static void vgacon_invert_region(struct vc_data *c, u16 * p, int count)
621 {
622 	int col = vga_can_do_color;
623 
624 	while (count--) {
625 		u16 a = scr_readw(p);
626 		if (col)
627 			a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) |
628 			    (((a) & 0x0700) << 4);
629 		else
630 			a ^= ((a & 0x0700) == 0x0100) ? 0x7000 : 0x7700;
631 		scr_writew(a, p++);
632 	}
633 }
634 
635 static void vgacon_set_cursor_size(int xpos, int from, int to)
636 {
637 	unsigned long flags;
638 	int curs, cure;
639 
640 #ifdef TRIDENT_GLITCH
641 	if (xpos < 16)
642 		from--, to--;
643 #endif
644 
645 	if ((from == cursor_size_lastfrom) && (to == cursor_size_lastto))
646 		return;
647 	cursor_size_lastfrom = from;
648 	cursor_size_lastto = to;
649 
650 	spin_lock_irqsave(&vga_lock, flags);
651 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
652 		outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
653 		curs = inb_p(vga_video_port_val);
654 		outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
655 		cure = inb_p(vga_video_port_val);
656 	} else {
657 		curs = 0;
658 		cure = 0;
659 	}
660 
661 	curs = (curs & 0xc0) | from;
662 	cure = (cure & 0xe0) | to;
663 
664 	outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
665 	outb_p(curs, vga_video_port_val);
666 	outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
667 	outb_p(cure, vga_video_port_val);
668 	spin_unlock_irqrestore(&vga_lock, flags);
669 }
670 
671 static void vgacon_cursor(struct vc_data *c, int mode)
672 {
673 	if (c->vc_mode != KD_TEXT)
674 		return;
675 
676 	vgacon_restore_screen(c);
677 
678 	switch (mode) {
679 	case CM_ERASE:
680 		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
681 	        if (vga_video_type >= VIDEO_TYPE_VGAC)
682 			vgacon_set_cursor_size(c->vc_x, 31, 30);
683 		else
684 			vgacon_set_cursor_size(c->vc_x, 31, 31);
685 		break;
686 
687 	case CM_MOVE:
688 	case CM_DRAW:
689 		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
690 		switch (c->vc_cursor_type & 0x0f) {
691 		case CUR_UNDERLINE:
692 			vgacon_set_cursor_size(c->vc_x,
693 					       c->vc_font.height -
694 					       (c->vc_font.height <
695 						10 ? 2 : 3),
696 					       c->vc_font.height -
697 					       (c->vc_font.height <
698 						10 ? 1 : 2));
699 			break;
700 		case CUR_TWO_THIRDS:
701 			vgacon_set_cursor_size(c->vc_x,
702 					       c->vc_font.height / 3,
703 					       c->vc_font.height -
704 					       (c->vc_font.height <
705 						10 ? 1 : 2));
706 			break;
707 		case CUR_LOWER_THIRD:
708 			vgacon_set_cursor_size(c->vc_x,
709 					       (c->vc_font.height * 2) / 3,
710 					       c->vc_font.height -
711 					       (c->vc_font.height <
712 						10 ? 1 : 2));
713 			break;
714 		case CUR_LOWER_HALF:
715 			vgacon_set_cursor_size(c->vc_x,
716 					       c->vc_font.height / 2,
717 					       c->vc_font.height -
718 					       (c->vc_font.height <
719 						10 ? 1 : 2));
720 			break;
721 		case CUR_NONE:
722 			if (vga_video_type >= VIDEO_TYPE_VGAC)
723 				vgacon_set_cursor_size(c->vc_x, 31, 30);
724 			else
725 				vgacon_set_cursor_size(c->vc_x, 31, 31);
726 			break;
727 		default:
728 			vgacon_set_cursor_size(c->vc_x, 1,
729 					       c->vc_font.height);
730 			break;
731 		}
732 		break;
733 	}
734 }
735 
736 static int vgacon_doresize(struct vc_data *c,
737 		unsigned int width, unsigned int height)
738 {
739 	unsigned long flags;
740 	unsigned int scanlines = height * c->vc_font.height;
741 	u8 scanlines_lo = 0, r7 = 0, vsync_end = 0, mode, max_scan;
742 
743 	spin_lock_irqsave(&vga_lock, flags);
744 
745 	vgacon_xres = width * VGA_FONTWIDTH;
746 	vgacon_yres = height * c->vc_font.height;
747 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
748 		outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
749 		max_scan = inb_p(vga_video_port_val);
750 
751 		if (max_scan & 0x80)
752 			scanlines <<= 1;
753 
754 		outb_p(VGA_CRTC_MODE, vga_video_port_reg);
755 		mode = inb_p(vga_video_port_val);
756 
757 		if (mode & 0x04)
758 			scanlines >>= 1;
759 
760 		scanlines -= 1;
761 		scanlines_lo = scanlines & 0xff;
762 
763 		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
764 		r7 = inb_p(vga_video_port_val) & ~0x42;
765 
766 		if (scanlines & 0x100)
767 			r7 |= 0x02;
768 		if (scanlines & 0x200)
769 			r7 |= 0x40;
770 
771 		/* deprotect registers */
772 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
773 		vsync_end = inb_p(vga_video_port_val);
774 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
775 		outb_p(vsync_end & ~0x80, vga_video_port_val);
776 	}
777 
778 	outb_p(VGA_CRTC_H_DISP, vga_video_port_reg);
779 	outb_p(width - 1, vga_video_port_val);
780 	outb_p(VGA_CRTC_OFFSET, vga_video_port_reg);
781 	outb_p(width >> 1, vga_video_port_val);
782 
783 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
784 		outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
785 		outb_p(scanlines_lo, vga_video_port_val);
786 		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
787 		outb_p(r7,vga_video_port_val);
788 
789 		/* reprotect registers */
790 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
791 		outb_p(vsync_end, vga_video_port_val);
792 	}
793 
794 	spin_unlock_irqrestore(&vga_lock, flags);
795 	return 0;
796 }
797 
798 static int vgacon_switch(struct vc_data *c)
799 {
800 	int x = c->vc_cols * VGA_FONTWIDTH;
801 	int y = c->vc_rows * c->vc_font.height;
802 	int rows = screen_info.orig_video_lines * vga_default_font_height/
803 		c->vc_font.height;
804 	/*
805 	 * We need to save screen size here as it's the only way
806 	 * we can spot the screen has been resized and we need to
807 	 * set size of freshly allocated screens ourselves.
808 	 */
809 	vga_video_num_columns = c->vc_cols;
810 	vga_video_num_lines = c->vc_rows;
811 
812 	/* We can only copy out the size of the video buffer here,
813 	 * otherwise we get into VGA BIOS */
814 
815 	if (!vga_is_gfx) {
816 		scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
817 			    c->vc_screenbuf_size > vga_vram_size ?
818 				vga_vram_size : c->vc_screenbuf_size);
819 
820 		if ((vgacon_xres != x || vgacon_yres != y) &&
821 		    (!(vga_video_num_columns % 2) &&
822 		     vga_video_num_columns <= screen_info.orig_video_cols &&
823 		     vga_video_num_lines <= rows))
824 			vgacon_doresize(c, c->vc_cols, c->vc_rows);
825 	}
826 
827 	vgacon_scrollback_init(c->vc_size_row);
828 	return 0;		/* Redrawing not needed */
829 }
830 
831 static void vga_set_palette(struct vc_data *vc, unsigned char *table)
832 {
833 	int i, j;
834 
835 	vga_w(state.vgabase, VGA_PEL_MSK, 0xff);
836 	for (i = j = 0; i < 16; i++) {
837 		vga_w(state.vgabase, VGA_PEL_IW, table[i]);
838 		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
839 		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
840 		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
841 	}
842 }
843 
844 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table)
845 {
846 #ifdef CAN_LOAD_PALETTE
847 	if (vga_video_type != VIDEO_TYPE_VGAC || vga_palette_blanked
848 	    || !CON_IS_VISIBLE(vc))
849 		return -EINVAL;
850 	vga_set_palette(vc, table);
851 	return 0;
852 #else
853 	return -EINVAL;
854 #endif
855 }
856 
857 /* structure holding original VGA register settings */
858 static struct {
859 	unsigned char SeqCtrlIndex;	/* Sequencer Index reg.   */
860 	unsigned char CrtCtrlIndex;	/* CRT-Contr. Index reg.  */
861 	unsigned char CrtMiscIO;	/* Miscellaneous register */
862 	unsigned char HorizontalTotal;	/* CRT-Controller:00h */
863 	unsigned char HorizDisplayEnd;	/* CRT-Controller:01h */
864 	unsigned char StartHorizRetrace;	/* CRT-Controller:04h */
865 	unsigned char EndHorizRetrace;	/* CRT-Controller:05h */
866 	unsigned char Overflow;	/* CRT-Controller:07h */
867 	unsigned char StartVertRetrace;	/* CRT-Controller:10h */
868 	unsigned char EndVertRetrace;	/* CRT-Controller:11h */
869 	unsigned char ModeControl;	/* CRT-Controller:17h */
870 	unsigned char ClockingMode;	/* Seq-Controller:01h */
871 } vga_state;
872 
873 static void vga_vesa_blank(struct vgastate *state, int mode)
874 {
875 	/* save original values of VGA controller registers */
876 	if (!vga_vesa_blanked) {
877 		spin_lock_irq(&vga_lock);
878 		vga_state.SeqCtrlIndex = vga_r(state->vgabase, VGA_SEQ_I);
879 		vga_state.CrtCtrlIndex = inb_p(vga_video_port_reg);
880 		vga_state.CrtMiscIO = vga_r(state->vgabase, VGA_MIS_R);
881 		spin_unlock_irq(&vga_lock);
882 
883 		outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
884 		vga_state.HorizontalTotal = inb_p(vga_video_port_val);
885 		outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
886 		vga_state.HorizDisplayEnd = inb_p(vga_video_port_val);
887 		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
888 		vga_state.StartHorizRetrace = inb_p(vga_video_port_val);
889 		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
890 		vga_state.EndHorizRetrace = inb_p(vga_video_port_val);
891 		outb_p(0x07, vga_video_port_reg);	/* Overflow */
892 		vga_state.Overflow = inb_p(vga_video_port_val);
893 		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
894 		vga_state.StartVertRetrace = inb_p(vga_video_port_val);
895 		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
896 		vga_state.EndVertRetrace = inb_p(vga_video_port_val);
897 		outb_p(0x17, vga_video_port_reg);	/* ModeControl */
898 		vga_state.ModeControl = inb_p(vga_video_port_val);
899 		vga_state.ClockingMode = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
900 	}
901 
902 	/* assure that video is enabled */
903 	/* "0x20" is VIDEO_ENABLE_bit in register 01 of sequencer */
904 	spin_lock_irq(&vga_lock);
905 	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode | 0x20);
906 
907 	/* test for vertical retrace in process.... */
908 	if ((vga_state.CrtMiscIO & 0x80) == 0x80)
909 		vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO & 0xEF);
910 
911 	/*
912 	 * Set <End of vertical retrace> to minimum (0) and
913 	 * <Start of vertical Retrace> to maximum (incl. overflow)
914 	 * Result: turn off vertical sync (VSync) pulse.
915 	 */
916 	if (mode & VESA_VSYNC_SUSPEND) {
917 		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
918 		outb_p(0xff, vga_video_port_val);	/* maximum value */
919 		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
920 		outb_p(0x40, vga_video_port_val);	/* minimum (bits 0..3)  */
921 		outb_p(0x07, vga_video_port_reg);	/* Overflow */
922 		outb_p(vga_state.Overflow | 0x84, vga_video_port_val);	/* bits 9,10 of vert. retrace */
923 	}
924 
925 	if (mode & VESA_HSYNC_SUSPEND) {
926 		/*
927 		 * Set <End of horizontal retrace> to minimum (0) and
928 		 *  <Start of horizontal Retrace> to maximum
929 		 * Result: turn off horizontal sync (HSync) pulse.
930 		 */
931 		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
932 		outb_p(0xff, vga_video_port_val);	/* maximum */
933 		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
934 		outb_p(0x00, vga_video_port_val);	/* minimum (0) */
935 	}
936 
937 	/* restore both index registers */
938 	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
939 	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
940 	spin_unlock_irq(&vga_lock);
941 }
942 
943 static void vga_vesa_unblank(struct vgastate *state)
944 {
945 	/* restore original values of VGA controller registers */
946 	spin_lock_irq(&vga_lock);
947 	vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO);
948 
949 	outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
950 	outb_p(vga_state.HorizontalTotal, vga_video_port_val);
951 	outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
952 	outb_p(vga_state.HorizDisplayEnd, vga_video_port_val);
953 	outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
954 	outb_p(vga_state.StartHorizRetrace, vga_video_port_val);
955 	outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
956 	outb_p(vga_state.EndHorizRetrace, vga_video_port_val);
957 	outb_p(0x07, vga_video_port_reg);	/* Overflow */
958 	outb_p(vga_state.Overflow, vga_video_port_val);
959 	outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
960 	outb_p(vga_state.StartVertRetrace, vga_video_port_val);
961 	outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
962 	outb_p(vga_state.EndVertRetrace, vga_video_port_val);
963 	outb_p(0x17, vga_video_port_reg);	/* ModeControl */
964 	outb_p(vga_state.ModeControl, vga_video_port_val);
965 	/* ClockingMode */
966 	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode);
967 
968 	/* restore index/control registers */
969 	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
970 	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
971 	spin_unlock_irq(&vga_lock);
972 }
973 
974 static void vga_pal_blank(struct vgastate *state)
975 {
976 	int i;
977 
978 	vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
979 	for (i = 0; i < 16; i++) {
980 		vga_w(state->vgabase, VGA_PEL_IW, i);
981 		vga_w(state->vgabase, VGA_PEL_D, 0);
982 		vga_w(state->vgabase, VGA_PEL_D, 0);
983 		vga_w(state->vgabase, VGA_PEL_D, 0);
984 	}
985 }
986 
987 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch)
988 {
989 	switch (blank) {
990 	case 0:		/* Unblank */
991 		if (vga_vesa_blanked) {
992 			vga_vesa_unblank(&state);
993 			vga_vesa_blanked = 0;
994 		}
995 		if (vga_palette_blanked) {
996 			vga_set_palette(c, color_table);
997 			vga_palette_blanked = 0;
998 			return 0;
999 		}
1000 		vga_is_gfx = 0;
1001 		/* Tell console.c that it has to restore the screen itself */
1002 		return 1;
1003 	case 1:		/* Normal blanking */
1004 	case -1:	/* Obsolete */
1005 		if (!mode_switch && vga_video_type == VIDEO_TYPE_VGAC) {
1006 			vga_pal_blank(&state);
1007 			vga_palette_blanked = 1;
1008 			return 0;
1009 		}
1010 		vgacon_set_origin(c);
1011 		scr_memsetw((void *) vga_vram_base, BLANK,
1012 			    c->vc_screenbuf_size);
1013 		if (mode_switch)
1014 			vga_is_gfx = 1;
1015 		return 1;
1016 	default:		/* VESA blanking */
1017 		if (vga_video_type == VIDEO_TYPE_VGAC) {
1018 			vga_vesa_blank(&state, blank - 1);
1019 			vga_vesa_blanked = blank;
1020 		}
1021 		return 0;
1022 	}
1023 }
1024 
1025 /*
1026  * PIO_FONT support.
1027  *
1028  * The font loading code goes back to the codepage package by
1029  * Joel Hoffman (joel@wam.umd.edu). (He reports that the original
1030  * reference is: "From: p. 307 of _Programmer's Guide to PC & PS/2
1031  * Video Systems_ by Richard Wilton. 1987.  Microsoft Press".)
1032  *
1033  * Change for certain monochrome monitors by Yury Shevchuck
1034  * (sizif@botik.yaroslavl.su).
1035  */
1036 
1037 #ifdef CAN_LOAD_EGA_FONTS
1038 
1039 #define colourmap 0xa0000
1040 /* Pauline Middelink <middelin@polyware.iaf.nl> reports that we
1041    should use 0xA0000 for the bwmap as well.. */
1042 #define blackwmap 0xa0000
1043 #define cmapsz 8192
1044 
1045 static int vgacon_do_font_op(struct vgastate *state,char *arg,int set,int ch512)
1046 {
1047 	unsigned short video_port_status = vga_video_port_reg + 6;
1048 	int font_select = 0x00, beg, i;
1049 	char *charmap;
1050 
1051 	if (vga_video_type != VIDEO_TYPE_EGAM) {
1052 		charmap = (char *) VGA_MAP_MEM(colourmap, 0);
1053 		beg = 0x0e;
1054 #ifdef VGA_CAN_DO_64KB
1055 		if (vga_video_type == VIDEO_TYPE_VGAC)
1056 			beg = 0x06;
1057 #endif
1058 	} else {
1059 		charmap = (char *) VGA_MAP_MEM(blackwmap, 0);
1060 		beg = 0x0a;
1061 	}
1062 
1063 #ifdef BROKEN_GRAPHICS_PROGRAMS
1064 	/*
1065 	 * All fonts are loaded in slot 0 (0:1 for 512 ch)
1066 	 */
1067 
1068 	if (!arg)
1069 		return -EINVAL;	/* Return to default font not supported */
1070 
1071 	vga_font_is_default = 0;
1072 	font_select = ch512 ? 0x04 : 0x00;
1073 #else
1074 	/*
1075 	 * The default font is kept in slot 0 and is never touched.
1076 	 * A custom font is loaded in slot 2 (256 ch) or 2:3 (512 ch)
1077 	 */
1078 
1079 	if (set) {
1080 		vga_font_is_default = !arg;
1081 		if (!arg)
1082 			ch512 = 0;	/* Default font is always 256 */
1083 		font_select = arg ? (ch512 ? 0x0e : 0x0a) : 0x00;
1084 	}
1085 
1086 	if (!vga_font_is_default)
1087 		charmap += 4 * cmapsz;
1088 #endif
1089 
1090 	unlock_kernel();
1091 	spin_lock_irq(&vga_lock);
1092 	/* First, the Sequencer */
1093 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
1094 	/* CPU writes only to map 2 */
1095 	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x04);
1096 	/* Sequential addressing */
1097 	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x07);
1098 	/* Clear synchronous reset */
1099 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
1100 
1101 	/* Now, the graphics controller, select map 2 */
1102 	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x02);
1103 	/* disable odd-even addressing */
1104 	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x00);
1105 	/* map start at A000:0000 */
1106 	vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x00);
1107 	spin_unlock_irq(&vga_lock);
1108 
1109 	if (arg) {
1110 		if (set)
1111 			for (i = 0; i < cmapsz; i++)
1112 				vga_writeb(arg[i], charmap + i);
1113 		else
1114 			for (i = 0; i < cmapsz; i++)
1115 				arg[i] = vga_readb(charmap + i);
1116 
1117 		/*
1118 		 * In 512-character mode, the character map is not contiguous if
1119 		 * we want to remain EGA compatible -- which we do
1120 		 */
1121 
1122 		if (ch512) {
1123 			charmap += 2 * cmapsz;
1124 			arg += cmapsz;
1125 			if (set)
1126 				for (i = 0; i < cmapsz; i++)
1127 					vga_writeb(arg[i], charmap + i);
1128 			else
1129 				for (i = 0; i < cmapsz; i++)
1130 					arg[i] = vga_readb(charmap + i);
1131 		}
1132 	}
1133 
1134 	spin_lock_irq(&vga_lock);
1135 	/* First, the sequencer, Synchronous reset */
1136 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);
1137 	/* CPU writes to maps 0 and 1 */
1138 	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x03);
1139 	/* odd-even addressing */
1140 	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x03);
1141 	/* Character Map Select */
1142 	if (set)
1143 		vga_wseq(state->vgabase, VGA_SEQ_CHARACTER_MAP, font_select);
1144 	/* clear synchronous reset */
1145 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
1146 
1147 	/* Now, the graphics controller, select map 0 for CPU */
1148 	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x00);
1149 	/* enable even-odd addressing */
1150 	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x10);
1151 	/* map starts at b800:0 or b000:0 */
1152 	vga_wgfx(state->vgabase, VGA_GFX_MISC, beg);
1153 
1154 	/* if 512 char mode is already enabled don't re-enable it. */
1155 	if ((set) && (ch512 != vga_512_chars)) {
1156 		/* attribute controller */
1157 		for (i = 0; i < MAX_NR_CONSOLES; i++) {
1158 			struct vc_data *c = vc_cons[i].d;
1159 			if (c && c->vc_sw == &vga_con)
1160 				c->vc_hi_font_mask = ch512 ? 0x0800 : 0;
1161 		}
1162 		vga_512_chars = ch512;
1163 		/* 256-char: enable intensity bit
1164 		   512-char: disable intensity bit */
1165 		inb_p(video_port_status);	/* clear address flip-flop */
1166 		/* color plane enable register */
1167 		vga_wattr(state->vgabase, VGA_ATC_PLANE_ENABLE, ch512 ? 0x07 : 0x0f);
1168 		/* Wilton (1987) mentions the following; I don't know what
1169 		   it means, but it works, and it appears necessary */
1170 		inb_p(video_port_status);
1171 		vga_wattr(state->vgabase, VGA_AR_ENABLE_DISPLAY, 0);
1172 	}
1173 	spin_unlock_irq(&vga_lock);
1174 	lock_kernel();
1175 	return 0;
1176 }
1177 
1178 /*
1179  * Adjust the screen to fit a font of a certain height
1180  */
1181 static int vgacon_adjust_height(struct vc_data *vc, unsigned fontheight)
1182 {
1183 	unsigned char ovr, vde, fsr;
1184 	int rows, maxscan, i;
1185 
1186 	rows = vc->vc_scan_lines / fontheight;	/* Number of video rows we end up with */
1187 	maxscan = rows * fontheight - 1;	/* Scan lines to actually display-1 */
1188 
1189 	/* Reprogram the CRTC for the new font size
1190 	   Note: the attempt to read the overflow register will fail
1191 	   on an EGA, but using 0xff for the previous value appears to
1192 	   be OK for EGA text modes in the range 257-512 scan lines, so I
1193 	   guess we don't need to worry about it.
1194 
1195 	   The same applies for the spill bits in the font size and cursor
1196 	   registers; they are write-only on EGA, but it appears that they
1197 	   are all don't care bits on EGA, so I guess it doesn't matter. */
1198 
1199 	spin_lock_irq(&vga_lock);
1200 	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
1201 	ovr = inb_p(vga_video_port_val);
1202 	outb_p(0x09, vga_video_port_reg);	/* Font size register */
1203 	fsr = inb_p(vga_video_port_val);
1204 	spin_unlock_irq(&vga_lock);
1205 
1206 	vde = maxscan & 0xff;	/* Vertical display end reg */
1207 	ovr = (ovr & 0xbd) +	/* Overflow register */
1208 	    ((maxscan & 0x100) >> 7) + ((maxscan & 0x200) >> 3);
1209 	fsr = (fsr & 0xe0) + (fontheight - 1);	/*  Font size register */
1210 
1211 	spin_lock_irq(&vga_lock);
1212 	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
1213 	outb_p(ovr, vga_video_port_val);
1214 	outb_p(0x09, vga_video_port_reg);	/* Font size */
1215 	outb_p(fsr, vga_video_port_val);
1216 	outb_p(0x12, vga_video_port_reg);	/* Vertical display limit */
1217 	outb_p(vde, vga_video_port_val);
1218 	spin_unlock_irq(&vga_lock);
1219 	vga_video_font_height = fontheight;
1220 
1221 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
1222 		struct vc_data *c = vc_cons[i].d;
1223 
1224 		if (c && c->vc_sw == &vga_con) {
1225 			if (CON_IS_VISIBLE(c)) {
1226 			        /* void size to cause regs to be rewritten */
1227 				cursor_size_lastfrom = 0;
1228 				cursor_size_lastto = 0;
1229 				c->vc_sw->con_cursor(c, CM_DRAW);
1230 			}
1231 			c->vc_font.height = fontheight;
1232 			vc_resize(c, 0, rows);	/* Adjust console size */
1233 		}
1234 	}
1235 	return 0;
1236 }
1237 
1238 static int vgacon_font_set(struct vc_data *c, struct console_font *font, unsigned flags)
1239 {
1240 	unsigned charcount = font->charcount;
1241 	int rc;
1242 
1243 	if (vga_video_type < VIDEO_TYPE_EGAM)
1244 		return -EINVAL;
1245 
1246 	if (font->width != VGA_FONTWIDTH ||
1247 	    (charcount != 256 && charcount != 512))
1248 		return -EINVAL;
1249 
1250 	rc = vgacon_do_font_op(&state, font->data, 1, charcount == 512);
1251 	if (rc)
1252 		return rc;
1253 
1254 	if (!(flags & KD_FONT_FLAG_DONT_RECALC))
1255 		rc = vgacon_adjust_height(c, font->height);
1256 	return rc;
1257 }
1258 
1259 static int vgacon_font_get(struct vc_data *c, struct console_font *font)
1260 {
1261 	if (vga_video_type < VIDEO_TYPE_EGAM)
1262 		return -EINVAL;
1263 
1264 	font->width = VGA_FONTWIDTH;
1265 	font->height = c->vc_font.height;
1266 	font->charcount = vga_512_chars ? 512 : 256;
1267 	if (!font->data)
1268 		return 0;
1269 	return vgacon_do_font_op(&state, font->data, 0, 0);
1270 }
1271 
1272 #else
1273 
1274 #define vgacon_font_set NULL
1275 #define vgacon_font_get NULL
1276 
1277 #endif
1278 
1279 static int vgacon_resize(struct vc_data *c, unsigned int width,
1280 			 unsigned int height, unsigned int user)
1281 {
1282 	if (width % 2 || width > screen_info.orig_video_cols ||
1283 	    height > (screen_info.orig_video_lines * vga_default_font_height)/
1284 	    c->vc_font.height)
1285 		/* let svgatextmode tinker with video timings and
1286 		   return success */
1287 		return (user) ? 0 : -EINVAL;
1288 
1289 	if (CON_IS_VISIBLE(c) && !vga_is_gfx) /* who knows */
1290 		vgacon_doresize(c, width, height);
1291 	return 0;
1292 }
1293 
1294 static int vgacon_set_origin(struct vc_data *c)
1295 {
1296 	if (vga_is_gfx ||	/* We don't play origin tricks in graphic modes */
1297 	    (console_blanked && !vga_palette_blanked))	/* Nor we write to blanked screens */
1298 		return 0;
1299 	c->vc_origin = c->vc_visible_origin = vga_vram_base;
1300 	vga_set_mem_top(c);
1301 	vga_rolled_over = 0;
1302 	return 1;
1303 }
1304 
1305 static void vgacon_save_screen(struct vc_data *c)
1306 {
1307 	static int vga_bootup_console = 0;
1308 
1309 	if (!vga_bootup_console) {
1310 		/* This is a gross hack, but here is the only place we can
1311 		 * set bootup console parameters without messing up generic
1312 		 * console initialization routines.
1313 		 */
1314 		vga_bootup_console = 1;
1315 		c->vc_x = screen_info.orig_x;
1316 		c->vc_y = screen_info.orig_y;
1317 	}
1318 
1319 	/* We can't copy in more then the size of the video buffer,
1320 	 * or we'll be copying in VGA BIOS */
1321 
1322 	if (!vga_is_gfx)
1323 		scr_memcpyw((u16 *) c->vc_screenbuf, (u16 *) c->vc_origin,
1324 			    c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size);
1325 }
1326 
1327 static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
1328 			 int lines)
1329 {
1330 	unsigned long oldo;
1331 	unsigned int delta;
1332 
1333 	if (t || b != c->vc_rows || vga_is_gfx || c->vc_mode != KD_TEXT)
1334 		return 0;
1335 
1336 	if (!vga_hardscroll_enabled || lines >= c->vc_rows / 2)
1337 		return 0;
1338 
1339 	vgacon_restore_screen(c);
1340 	oldo = c->vc_origin;
1341 	delta = lines * c->vc_size_row;
1342 	if (dir == SM_UP) {
1343 		vgacon_scrollback_update(c, t, lines);
1344 		if (c->vc_scr_end + delta >= vga_vram_end) {
1345 			scr_memcpyw((u16 *) vga_vram_base,
1346 				    (u16 *) (oldo + delta),
1347 				    c->vc_screenbuf_size - delta);
1348 			c->vc_origin = vga_vram_base;
1349 			vga_rolled_over = oldo - vga_vram_base;
1350 		} else
1351 			c->vc_origin += delta;
1352 		scr_memsetw((u16 *) (c->vc_origin + c->vc_screenbuf_size -
1353 				     delta), c->vc_scrl_erase_char,
1354 			    delta);
1355 	} else {
1356 		if (oldo - delta < vga_vram_base) {
1357 			scr_memmovew((u16 *) (vga_vram_end -
1358 					      c->vc_screenbuf_size +
1359 					      delta), (u16 *) oldo,
1360 				     c->vc_screenbuf_size - delta);
1361 			c->vc_origin = vga_vram_end - c->vc_screenbuf_size;
1362 			vga_rolled_over = 0;
1363 		} else
1364 			c->vc_origin -= delta;
1365 		c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1366 		scr_memsetw((u16 *) (c->vc_origin), c->vc_scrl_erase_char,
1367 			    delta);
1368 	}
1369 	c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1370 	c->vc_visible_origin = c->vc_origin;
1371 	vga_set_mem_top(c);
1372 	c->vc_pos = (c->vc_pos - oldo) + c->vc_origin;
1373 	return 1;
1374 }
1375 
1376 
1377 /*
1378  *  The console `switch' structure for the VGA based console
1379  */
1380 
1381 static int vgacon_dummy(struct vc_data *c)
1382 {
1383 	return 0;
1384 }
1385 
1386 #define DUMMY (void *) vgacon_dummy
1387 
1388 const struct consw vga_con = {
1389 	.owner = THIS_MODULE,
1390 	.con_startup = vgacon_startup,
1391 	.con_init = vgacon_init,
1392 	.con_deinit = vgacon_deinit,
1393 	.con_clear = DUMMY,
1394 	.con_putc = DUMMY,
1395 	.con_putcs = DUMMY,
1396 	.con_cursor = vgacon_cursor,
1397 	.con_scroll = vgacon_scroll,
1398 	.con_bmove = DUMMY,
1399 	.con_switch = vgacon_switch,
1400 	.con_blank = vgacon_blank,
1401 	.con_font_set = vgacon_font_set,
1402 	.con_font_get = vgacon_font_get,
1403 	.con_resize = vgacon_resize,
1404 	.con_set_palette = vgacon_set_palette,
1405 	.con_scrolldelta = vgacon_scrolldelta,
1406 	.con_set_origin = vgacon_set_origin,
1407 	.con_save_screen = vgacon_save_screen,
1408 	.con_build_attr = vgacon_build_attr,
1409 	.con_invert_region = vgacon_invert_region,
1410 };
1411 
1412 MODULE_LICENSE("GPL");
1413