xref: /openbmc/linux/drivers/video/console/vgacon.c (revision 9ac8d3fb)
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;
243 
244 	if (!lines) {
245 		c->vc_visible_origin = c->vc_origin;
246 		vga_set_mem_top(c);
247 		return 1;
248 	}
249 
250 	if (!vgacon_scrollback)
251 		return 1;
252 
253 	if (!vgacon_scrollback_save) {
254 		vgacon_cursor(c, CM_ERASE);
255 		vgacon_save_screen(c);
256 		vgacon_scrollback_save = 1;
257 	}
258 
259 	vgacon_scrollback_restore = 0;
260 	start = vgacon_scrollback_cur + lines;
261 	end = start + abs(lines);
262 
263 	if (start < 0)
264 		start = 0;
265 
266 	if (start > vgacon_scrollback_cnt)
267 		start = vgacon_scrollback_cnt;
268 
269 	if (end < 0)
270 		end = 0;
271 
272 	if (end > vgacon_scrollback_cnt)
273 		end = vgacon_scrollback_cnt;
274 
275 	vgacon_scrollback_cur = start;
276 	count = end - start;
277 	soff = vgacon_scrollback_tail - ((vgacon_scrollback_cnt - end) *
278 					 c->vc_size_row);
279 	soff -= count * c->vc_size_row;
280 
281 	if (soff < 0)
282 		soff += vgacon_scrollback_size;
283 
284 	count = vgacon_scrollback_cnt - start;
285 
286 	if (count > c->vc_rows)
287 		count = c->vc_rows;
288 
289 	if (count) {
290 		int copysize;
291 
292 		int diff = c->vc_rows - count;
293 		void *d = (void *) c->vc_origin;
294 		void *s = (void *) c->vc_screenbuf;
295 
296 		count *= c->vc_size_row;
297 		/* how much memory to end of buffer left? */
298 		copysize = min(count, vgacon_scrollback_size - soff);
299 		scr_memcpyw(d, vgacon_scrollback + soff, copysize);
300 		d += copysize;
301 		count -= copysize;
302 
303 		if (count) {
304 			scr_memcpyw(d, vgacon_scrollback, count);
305 			d += count;
306 		}
307 
308 		if (diff)
309 			scr_memcpyw(d, s, diff * c->vc_size_row);
310 	} else
311 		vgacon_cursor(c, CM_MOVE);
312 
313 	return 1;
314 }
315 #else
316 #define vgacon_scrollback_startup(...) do { } while (0)
317 #define vgacon_scrollback_init(...)    do { } while (0)
318 #define vgacon_scrollback_update(...)  do { } while (0)
319 
320 static void vgacon_restore_screen(struct vc_data *c)
321 {
322 	if (c->vc_origin != c->vc_visible_origin)
323 		vgacon_scrolldelta(c, 0);
324 }
325 
326 static int vgacon_scrolldelta(struct vc_data *c, int lines)
327 {
328 	if (!lines)		/* Turn scrollback off */
329 		c->vc_visible_origin = c->vc_origin;
330 	else {
331 		int margin = c->vc_size_row * 4;
332 		int ul, we, p, st;
333 
334 		if (vga_rolled_over >
335 		    (c->vc_scr_end - vga_vram_base) + margin) {
336 			ul = c->vc_scr_end - vga_vram_base;
337 			we = vga_rolled_over + c->vc_size_row;
338 		} else {
339 			ul = 0;
340 			we = vga_vram_size;
341 		}
342 		p = (c->vc_visible_origin - vga_vram_base - ul + we) % we +
343 		    lines * c->vc_size_row;
344 		st = (c->vc_origin - vga_vram_base - ul + we) % we;
345 		if (st < 2 * margin)
346 			margin = 0;
347 		if (p < margin)
348 			p = 0;
349 		if (p > st - margin)
350 			p = st;
351 		c->vc_visible_origin = vga_vram_base + (p + ul) % we;
352 	}
353 	vga_set_mem_top(c);
354 	return 1;
355 }
356 #endif /* CONFIG_VGACON_SOFT_SCROLLBACK */
357 
358 static const char *vgacon_startup(void)
359 {
360 	const char *display_desc = NULL;
361 	u16 saved1, saved2;
362 	volatile u16 *p;
363 
364 	if (screen_info.orig_video_isVGA == VIDEO_TYPE_VLFB) {
365 	      no_vga:
366 #ifdef CONFIG_DUMMY_CONSOLE
367 		conswitchp = &dummy_con;
368 		return conswitchp->con_startup();
369 #else
370 		return NULL;
371 #endif
372 	}
373 
374 	/* boot_params.screen_info initialized? */
375 	if ((screen_info.orig_video_mode  == 0) &&
376 	    (screen_info.orig_video_lines == 0) &&
377 	    (screen_info.orig_video_cols  == 0))
378 		goto no_vga;
379 
380 	/* VGA16 modes are not handled by VGACON */
381 	if ((screen_info.orig_video_mode == 0x0D) ||	/* 320x200/4 */
382 	    (screen_info.orig_video_mode == 0x0E) ||	/* 640x200/4 */
383 	    (screen_info.orig_video_mode == 0x10) ||	/* 640x350/4 */
384 	    (screen_info.orig_video_mode == 0x12) ||	/* 640x480/4 */
385 	    (screen_info.orig_video_mode == 0x6A))	/* 800x600/4 (VESA) */
386 		goto no_vga;
387 
388 	vga_video_num_lines = screen_info.orig_video_lines;
389 	vga_video_num_columns = screen_info.orig_video_cols;
390 	state.vgabase = NULL;
391 
392 	if (screen_info.orig_video_mode == 7) {
393 		/* Monochrome display */
394 		vga_vram_base = 0xb0000;
395 		vga_video_port_reg = VGA_CRT_IM;
396 		vga_video_port_val = VGA_CRT_DM;
397 		if ((screen_info.orig_video_ega_bx & 0xff) != 0x10) {
398 			static struct resource ega_console_resource =
399 			    { .name = "ega", .start = 0x3B0, .end = 0x3BF };
400 			vga_video_type = VIDEO_TYPE_EGAM;
401 			vga_vram_size = 0x8000;
402 			display_desc = "EGA+";
403 			request_resource(&ioport_resource,
404 					 &ega_console_resource);
405 		} else {
406 			static struct resource mda1_console_resource =
407 			    { .name = "mda", .start = 0x3B0, .end = 0x3BB };
408 			static struct resource mda2_console_resource =
409 			    { .name = "mda", .start = 0x3BF, .end = 0x3BF };
410 			vga_video_type = VIDEO_TYPE_MDA;
411 			vga_vram_size = 0x2000;
412 			display_desc = "*MDA";
413 			request_resource(&ioport_resource,
414 					 &mda1_console_resource);
415 			request_resource(&ioport_resource,
416 					 &mda2_console_resource);
417 			vga_video_font_height = 14;
418 		}
419 	} else {
420 		/* If not, it is color. */
421 		vga_can_do_color = 1;
422 		vga_vram_base = 0xb8000;
423 		vga_video_port_reg = VGA_CRT_IC;
424 		vga_video_port_val = VGA_CRT_DC;
425 		if ((screen_info.orig_video_ega_bx & 0xff) != 0x10) {
426 			int i;
427 
428 			vga_vram_size = 0x8000;
429 
430 			if (!screen_info.orig_video_isVGA) {
431 				static struct resource ega_console_resource
432 				    = { .name = "ega", .start = 0x3C0, .end = 0x3DF };
433 				vga_video_type = VIDEO_TYPE_EGAC;
434 				display_desc = "EGA";
435 				request_resource(&ioport_resource,
436 						 &ega_console_resource);
437 			} else {
438 				static struct resource vga_console_resource
439 				    = { .name = "vga+", .start = 0x3C0, .end = 0x3DF };
440 				vga_video_type = VIDEO_TYPE_VGAC;
441 				display_desc = "VGA+";
442 				request_resource(&ioport_resource,
443 						 &vga_console_resource);
444 
445 #ifdef VGA_CAN_DO_64KB
446 				/*
447 				 * get 64K rather than 32K of video RAM.
448 				 * This doesn't actually work on all "VGA"
449 				 * controllers (it seems like setting MM=01
450 				 * and COE=1 isn't necessarily a good idea)
451 				 */
452 				vga_vram_base = 0xa0000;
453 				vga_vram_size = 0x10000;
454 				outb_p(6, VGA_GFX_I);
455 				outb_p(6, VGA_GFX_D);
456 #endif
457 				/*
458 				 * Normalise the palette registers, to point
459 				 * the 16 screen colours to the first 16
460 				 * DAC entries.
461 				 */
462 
463 				for (i = 0; i < 16; i++) {
464 					inb_p(VGA_IS1_RC);
465 					outb_p(i, VGA_ATT_W);
466 					outb_p(i, VGA_ATT_W);
467 				}
468 				outb_p(0x20, VGA_ATT_W);
469 
470 				/*
471 				 * Now set the DAC registers back to their
472 				 * default values
473 				 */
474 				for (i = 0; i < 16; i++) {
475 					outb_p(color_table[i], VGA_PEL_IW);
476 					outb_p(default_red[i], VGA_PEL_D);
477 					outb_p(default_grn[i], VGA_PEL_D);
478 					outb_p(default_blu[i], VGA_PEL_D);
479 				}
480 			}
481 		} else {
482 			static struct resource cga_console_resource =
483 			    { .name = "cga", .start = 0x3D4, .end = 0x3D5 };
484 			vga_video_type = VIDEO_TYPE_CGA;
485 			vga_vram_size = 0x2000;
486 			display_desc = "*CGA";
487 			request_resource(&ioport_resource,
488 					 &cga_console_resource);
489 			vga_video_font_height = 8;
490 		}
491 	}
492 
493 	vga_vram_base = VGA_MAP_MEM(vga_vram_base, vga_vram_size);
494 	vga_vram_end = vga_vram_base + vga_vram_size;
495 
496 	/*
497 	 *      Find out if there is a graphics card present.
498 	 *      Are there smarter methods around?
499 	 */
500 	p = (volatile u16 *) vga_vram_base;
501 	saved1 = scr_readw(p);
502 	saved2 = scr_readw(p + 1);
503 	scr_writew(0xAA55, p);
504 	scr_writew(0x55AA, p + 1);
505 	if (scr_readw(p) != 0xAA55 || scr_readw(p + 1) != 0x55AA) {
506 		scr_writew(saved1, p);
507 		scr_writew(saved2, p + 1);
508 		goto no_vga;
509 	}
510 	scr_writew(0x55AA, p);
511 	scr_writew(0xAA55, p + 1);
512 	if (scr_readw(p) != 0x55AA || scr_readw(p + 1) != 0xAA55) {
513 		scr_writew(saved1, p);
514 		scr_writew(saved2, p + 1);
515 		goto no_vga;
516 	}
517 	scr_writew(saved1, p);
518 	scr_writew(saved2, p + 1);
519 
520 	if (vga_video_type == VIDEO_TYPE_EGAC
521 	    || vga_video_type == VIDEO_TYPE_VGAC
522 	    || vga_video_type == VIDEO_TYPE_EGAM) {
523 		vga_hardscroll_enabled = vga_hardscroll_user_enable;
524 		vga_default_font_height = screen_info.orig_video_points;
525 		vga_video_font_height = screen_info.orig_video_points;
526 		/* This may be suboptimal but is a safe bet - go with it */
527 		vga_scan_lines =
528 		    vga_video_font_height * vga_video_num_lines;
529 	}
530 
531 	vgacon_xres = screen_info.orig_video_cols * VGA_FONTWIDTH;
532 	vgacon_yres = vga_scan_lines;
533 
534 	if (!vga_init_done) {
535 		vgacon_scrollback_startup();
536 		vga_init_done = 1;
537 	}
538 
539 	return display_desc;
540 }
541 
542 static void vgacon_init(struct vc_data *c, int init)
543 {
544 	unsigned long p;
545 
546 	/*
547 	 * We cannot be loaded as a module, therefore init is always 1,
548 	 * but vgacon_init can be called more than once, and init will
549 	 * not be 1.
550 	 */
551 	c->vc_can_do_color = vga_can_do_color;
552 
553 	/* set dimensions manually if init != 0 since vc_resize() will fail */
554 	if (init) {
555 		c->vc_cols = vga_video_num_columns;
556 		c->vc_rows = vga_video_num_lines;
557 	} else
558 		vc_resize(c, vga_video_num_columns, vga_video_num_lines);
559 
560 	c->vc_scan_lines = vga_scan_lines;
561 	c->vc_font.height = vga_video_font_height;
562 	c->vc_complement_mask = 0x7700;
563 	if (vga_512_chars)
564 		c->vc_hi_font_mask = 0x0800;
565 	p = *c->vc_uni_pagedir_loc;
566 	if (c->vc_uni_pagedir_loc == &c->vc_uni_pagedir ||
567 	    !--c->vc_uni_pagedir_loc[1])
568 		con_free_unimap(c);
569 	c->vc_uni_pagedir_loc = vgacon_uni_pagedir;
570 	vgacon_uni_pagedir[1]++;
571 	if (!vgacon_uni_pagedir[0] && p)
572 		con_set_default_unimap(c);
573 }
574 
575 static void vgacon_deinit(struct vc_data *c)
576 {
577 	/* When closing the last console, reset video origin */
578 	if (!--vgacon_uni_pagedir[1]) {
579 		c->vc_visible_origin = vga_vram_base;
580 		vga_set_mem_top(c);
581 		con_free_unimap(c);
582 	}
583 	c->vc_uni_pagedir_loc = &c->vc_uni_pagedir;
584 	con_set_default_unimap(c);
585 }
586 
587 static u8 vgacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
588 			    u8 blink, u8 underline, u8 reverse, u8 italic)
589 {
590 	u8 attr = color;
591 
592 	if (vga_can_do_color) {
593 		if (italic)
594 			attr = (attr & 0xF0) | c->vc_itcolor;
595 		else if (underline)
596 			attr = (attr & 0xf0) | c->vc_ulcolor;
597 		else if (intensity == 0)
598 			attr = (attr & 0xf0) | c->vc_halfcolor;
599 	}
600 	if (reverse)
601 		attr =
602 		    ((attr) & 0x88) | ((((attr) >> 4) | ((attr) << 4)) &
603 				       0x77);
604 	if (blink)
605 		attr ^= 0x80;
606 	if (intensity == 2)
607 		attr ^= 0x08;
608 	if (!vga_can_do_color) {
609 		if (italic)
610 			attr = (attr & 0xF8) | 0x02;
611 		else if (underline)
612 			attr = (attr & 0xf8) | 0x01;
613 		else if (intensity == 0)
614 			attr = (attr & 0xf0) | 0x08;
615 	}
616 	return attr;
617 }
618 
619 static void vgacon_invert_region(struct vc_data *c, u16 * p, int count)
620 {
621 	int col = vga_can_do_color;
622 
623 	while (count--) {
624 		u16 a = scr_readw(p);
625 		if (col)
626 			a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) |
627 			    (((a) & 0x0700) << 4);
628 		else
629 			a ^= ((a & 0x0700) == 0x0100) ? 0x7000 : 0x7700;
630 		scr_writew(a, p++);
631 	}
632 }
633 
634 static void vgacon_set_cursor_size(int xpos, int from, int to)
635 {
636 	unsigned long flags;
637 	int curs, cure;
638 
639 #ifdef TRIDENT_GLITCH
640 	if (xpos < 16)
641 		from--, to--;
642 #endif
643 
644 	if ((from == cursor_size_lastfrom) && (to == cursor_size_lastto))
645 		return;
646 	cursor_size_lastfrom = from;
647 	cursor_size_lastto = to;
648 
649 	spin_lock_irqsave(&vga_lock, flags);
650 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
651 		outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
652 		curs = inb_p(vga_video_port_val);
653 		outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
654 		cure = inb_p(vga_video_port_val);
655 	} else {
656 		curs = 0;
657 		cure = 0;
658 	}
659 
660 	curs = (curs & 0xc0) | from;
661 	cure = (cure & 0xe0) | to;
662 
663 	outb_p(VGA_CRTC_CURSOR_START, vga_video_port_reg);
664 	outb_p(curs, vga_video_port_val);
665 	outb_p(VGA_CRTC_CURSOR_END, vga_video_port_reg);
666 	outb_p(cure, vga_video_port_val);
667 	spin_unlock_irqrestore(&vga_lock, flags);
668 }
669 
670 static void vgacon_cursor(struct vc_data *c, int mode)
671 {
672 	if (c->vc_mode != KD_TEXT)
673 		return;
674 
675 	vgacon_restore_screen(c);
676 
677 	switch (mode) {
678 	case CM_ERASE:
679 		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
680 	        if (vga_video_type >= VIDEO_TYPE_VGAC)
681 			vgacon_set_cursor_size(c->vc_x, 31, 30);
682 		else
683 			vgacon_set_cursor_size(c->vc_x, 31, 31);
684 		break;
685 
686 	case CM_MOVE:
687 	case CM_DRAW:
688 		write_vga(14, (c->vc_pos - vga_vram_base) / 2);
689 		switch (c->vc_cursor_type & 0x0f) {
690 		case CUR_UNDERLINE:
691 			vgacon_set_cursor_size(c->vc_x,
692 					       c->vc_font.height -
693 					       (c->vc_font.height <
694 						10 ? 2 : 3),
695 					       c->vc_font.height -
696 					       (c->vc_font.height <
697 						10 ? 1 : 2));
698 			break;
699 		case CUR_TWO_THIRDS:
700 			vgacon_set_cursor_size(c->vc_x,
701 					       c->vc_font.height / 3,
702 					       c->vc_font.height -
703 					       (c->vc_font.height <
704 						10 ? 1 : 2));
705 			break;
706 		case CUR_LOWER_THIRD:
707 			vgacon_set_cursor_size(c->vc_x,
708 					       (c->vc_font.height * 2) / 3,
709 					       c->vc_font.height -
710 					       (c->vc_font.height <
711 						10 ? 1 : 2));
712 			break;
713 		case CUR_LOWER_HALF:
714 			vgacon_set_cursor_size(c->vc_x,
715 					       c->vc_font.height / 2,
716 					       c->vc_font.height -
717 					       (c->vc_font.height <
718 						10 ? 1 : 2));
719 			break;
720 		case CUR_NONE:
721 			if (vga_video_type >= VIDEO_TYPE_VGAC)
722 				vgacon_set_cursor_size(c->vc_x, 31, 30);
723 			else
724 				vgacon_set_cursor_size(c->vc_x, 31, 31);
725 			break;
726 		default:
727 			vgacon_set_cursor_size(c->vc_x, 1,
728 					       c->vc_font.height);
729 			break;
730 		}
731 		break;
732 	}
733 }
734 
735 static int vgacon_doresize(struct vc_data *c,
736 		unsigned int width, unsigned int height)
737 {
738 	unsigned long flags;
739 	unsigned int scanlines = height * c->vc_font.height;
740 	u8 scanlines_lo = 0, r7 = 0, vsync_end = 0, mode, max_scan;
741 
742 	spin_lock_irqsave(&vga_lock, flags);
743 
744 	vgacon_xres = width * VGA_FONTWIDTH;
745 	vgacon_yres = height * c->vc_font.height;
746 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
747 		outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
748 		max_scan = inb_p(vga_video_port_val);
749 
750 		if (max_scan & 0x80)
751 			scanlines <<= 1;
752 
753 		outb_p(VGA_CRTC_MODE, vga_video_port_reg);
754 		mode = inb_p(vga_video_port_val);
755 
756 		if (mode & 0x04)
757 			scanlines >>= 1;
758 
759 		scanlines -= 1;
760 		scanlines_lo = scanlines & 0xff;
761 
762 		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
763 		r7 = inb_p(vga_video_port_val) & ~0x42;
764 
765 		if (scanlines & 0x100)
766 			r7 |= 0x02;
767 		if (scanlines & 0x200)
768 			r7 |= 0x40;
769 
770 		/* deprotect registers */
771 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
772 		vsync_end = inb_p(vga_video_port_val);
773 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
774 		outb_p(vsync_end & ~0x80, vga_video_port_val);
775 	}
776 
777 	outb_p(VGA_CRTC_H_DISP, vga_video_port_reg);
778 	outb_p(width - 1, vga_video_port_val);
779 	outb_p(VGA_CRTC_OFFSET, vga_video_port_reg);
780 	outb_p(width >> 1, vga_video_port_val);
781 
782 	if (vga_video_type >= VIDEO_TYPE_VGAC) {
783 		outb_p(VGA_CRTC_V_DISP_END, vga_video_port_reg);
784 		outb_p(scanlines_lo, vga_video_port_val);
785 		outb_p(VGA_CRTC_OVERFLOW, vga_video_port_reg);
786 		outb_p(r7,vga_video_port_val);
787 
788 		/* reprotect registers */
789 		outb_p(VGA_CRTC_V_SYNC_END, vga_video_port_reg);
790 		outb_p(vsync_end, vga_video_port_val);
791 	}
792 
793 	spin_unlock_irqrestore(&vga_lock, flags);
794 	return 0;
795 }
796 
797 static int vgacon_switch(struct vc_data *c)
798 {
799 	int x = c->vc_cols * VGA_FONTWIDTH;
800 	int y = c->vc_rows * c->vc_font.height;
801 	int rows = screen_info.orig_video_lines * vga_default_font_height/
802 		c->vc_font.height;
803 	/*
804 	 * We need to save screen size here as it's the only way
805 	 * we can spot the screen has been resized and we need to
806 	 * set size of freshly allocated screens ourselves.
807 	 */
808 	vga_video_num_columns = c->vc_cols;
809 	vga_video_num_lines = c->vc_rows;
810 
811 	/* We can only copy out the size of the video buffer here,
812 	 * otherwise we get into VGA BIOS */
813 
814 	if (!vga_is_gfx) {
815 		scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
816 			    c->vc_screenbuf_size > vga_vram_size ?
817 				vga_vram_size : c->vc_screenbuf_size);
818 
819 		if ((vgacon_xres != x || vgacon_yres != y) &&
820 		    (!(vga_video_num_columns % 2) &&
821 		     vga_video_num_columns <= screen_info.orig_video_cols &&
822 		     vga_video_num_lines <= rows))
823 			vgacon_doresize(c, c->vc_cols, c->vc_rows);
824 	}
825 
826 	vgacon_scrollback_init(c->vc_size_row);
827 	return 0;		/* Redrawing not needed */
828 }
829 
830 static void vga_set_palette(struct vc_data *vc, unsigned char *table)
831 {
832 	int i, j;
833 
834 	vga_w(state.vgabase, VGA_PEL_MSK, 0xff);
835 	for (i = j = 0; i < 16; i++) {
836 		vga_w(state.vgabase, VGA_PEL_IW, table[i]);
837 		vga_w(state.vgabase, VGA_PEL_D, vc->vc_palette[j++] >> 2);
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 	}
841 }
842 
843 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table)
844 {
845 #ifdef CAN_LOAD_PALETTE
846 	if (vga_video_type != VIDEO_TYPE_VGAC || vga_palette_blanked
847 	    || !CON_IS_VISIBLE(vc))
848 		return -EINVAL;
849 	vga_set_palette(vc, table);
850 	return 0;
851 #else
852 	return -EINVAL;
853 #endif
854 }
855 
856 /* structure holding original VGA register settings */
857 static struct {
858 	unsigned char SeqCtrlIndex;	/* Sequencer Index reg.   */
859 	unsigned char CrtCtrlIndex;	/* CRT-Contr. Index reg.  */
860 	unsigned char CrtMiscIO;	/* Miscellaneous register */
861 	unsigned char HorizontalTotal;	/* CRT-Controller:00h */
862 	unsigned char HorizDisplayEnd;	/* CRT-Controller:01h */
863 	unsigned char StartHorizRetrace;	/* CRT-Controller:04h */
864 	unsigned char EndHorizRetrace;	/* CRT-Controller:05h */
865 	unsigned char Overflow;	/* CRT-Controller:07h */
866 	unsigned char StartVertRetrace;	/* CRT-Controller:10h */
867 	unsigned char EndVertRetrace;	/* CRT-Controller:11h */
868 	unsigned char ModeControl;	/* CRT-Controller:17h */
869 	unsigned char ClockingMode;	/* Seq-Controller:01h */
870 } vga_state;
871 
872 static void vga_vesa_blank(struct vgastate *state, int mode)
873 {
874 	/* save original values of VGA controller registers */
875 	if (!vga_vesa_blanked) {
876 		spin_lock_irq(&vga_lock);
877 		vga_state.SeqCtrlIndex = vga_r(state->vgabase, VGA_SEQ_I);
878 		vga_state.CrtCtrlIndex = inb_p(vga_video_port_reg);
879 		vga_state.CrtMiscIO = vga_r(state->vgabase, VGA_MIS_R);
880 		spin_unlock_irq(&vga_lock);
881 
882 		outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
883 		vga_state.HorizontalTotal = inb_p(vga_video_port_val);
884 		outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
885 		vga_state.HorizDisplayEnd = inb_p(vga_video_port_val);
886 		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
887 		vga_state.StartHorizRetrace = inb_p(vga_video_port_val);
888 		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
889 		vga_state.EndHorizRetrace = inb_p(vga_video_port_val);
890 		outb_p(0x07, vga_video_port_reg);	/* Overflow */
891 		vga_state.Overflow = inb_p(vga_video_port_val);
892 		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
893 		vga_state.StartVertRetrace = inb_p(vga_video_port_val);
894 		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
895 		vga_state.EndVertRetrace = inb_p(vga_video_port_val);
896 		outb_p(0x17, vga_video_port_reg);	/* ModeControl */
897 		vga_state.ModeControl = inb_p(vga_video_port_val);
898 		vga_state.ClockingMode = vga_rseq(state->vgabase, VGA_SEQ_CLOCK_MODE);
899 	}
900 
901 	/* assure that video is enabled */
902 	/* "0x20" is VIDEO_ENABLE_bit in register 01 of sequencer */
903 	spin_lock_irq(&vga_lock);
904 	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode | 0x20);
905 
906 	/* test for vertical retrace in process.... */
907 	if ((vga_state.CrtMiscIO & 0x80) == 0x80)
908 		vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO & 0xEF);
909 
910 	/*
911 	 * Set <End of vertical retrace> to minimum (0) and
912 	 * <Start of vertical Retrace> to maximum (incl. overflow)
913 	 * Result: turn off vertical sync (VSync) pulse.
914 	 */
915 	if (mode & VESA_VSYNC_SUSPEND) {
916 		outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
917 		outb_p(0xff, vga_video_port_val);	/* maximum value */
918 		outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
919 		outb_p(0x40, vga_video_port_val);	/* minimum (bits 0..3)  */
920 		outb_p(0x07, vga_video_port_reg);	/* Overflow */
921 		outb_p(vga_state.Overflow | 0x84, vga_video_port_val);	/* bits 9,10 of vert. retrace */
922 	}
923 
924 	if (mode & VESA_HSYNC_SUSPEND) {
925 		/*
926 		 * Set <End of horizontal retrace> to minimum (0) and
927 		 *  <Start of horizontal Retrace> to maximum
928 		 * Result: turn off horizontal sync (HSync) pulse.
929 		 */
930 		outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
931 		outb_p(0xff, vga_video_port_val);	/* maximum */
932 		outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
933 		outb_p(0x00, vga_video_port_val);	/* minimum (0) */
934 	}
935 
936 	/* restore both index registers */
937 	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
938 	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
939 	spin_unlock_irq(&vga_lock);
940 }
941 
942 static void vga_vesa_unblank(struct vgastate *state)
943 {
944 	/* restore original values of VGA controller registers */
945 	spin_lock_irq(&vga_lock);
946 	vga_w(state->vgabase, VGA_MIS_W, vga_state.CrtMiscIO);
947 
948 	outb_p(0x00, vga_video_port_reg);	/* HorizontalTotal */
949 	outb_p(vga_state.HorizontalTotal, vga_video_port_val);
950 	outb_p(0x01, vga_video_port_reg);	/* HorizDisplayEnd */
951 	outb_p(vga_state.HorizDisplayEnd, vga_video_port_val);
952 	outb_p(0x04, vga_video_port_reg);	/* StartHorizRetrace */
953 	outb_p(vga_state.StartHorizRetrace, vga_video_port_val);
954 	outb_p(0x05, vga_video_port_reg);	/* EndHorizRetrace */
955 	outb_p(vga_state.EndHorizRetrace, vga_video_port_val);
956 	outb_p(0x07, vga_video_port_reg);	/* Overflow */
957 	outb_p(vga_state.Overflow, vga_video_port_val);
958 	outb_p(0x10, vga_video_port_reg);	/* StartVertRetrace */
959 	outb_p(vga_state.StartVertRetrace, vga_video_port_val);
960 	outb_p(0x11, vga_video_port_reg);	/* EndVertRetrace */
961 	outb_p(vga_state.EndVertRetrace, vga_video_port_val);
962 	outb_p(0x17, vga_video_port_reg);	/* ModeControl */
963 	outb_p(vga_state.ModeControl, vga_video_port_val);
964 	/* ClockingMode */
965 	vga_wseq(state->vgabase, VGA_SEQ_CLOCK_MODE, vga_state.ClockingMode);
966 
967 	/* restore index/control registers */
968 	vga_w(state->vgabase, VGA_SEQ_I, vga_state.SeqCtrlIndex);
969 	outb_p(vga_state.CrtCtrlIndex, vga_video_port_reg);
970 	spin_unlock_irq(&vga_lock);
971 }
972 
973 static void vga_pal_blank(struct vgastate *state)
974 {
975 	int i;
976 
977 	vga_w(state->vgabase, VGA_PEL_MSK, 0xff);
978 	for (i = 0; i < 16; i++) {
979 		vga_w(state->vgabase, VGA_PEL_IW, i);
980 		vga_w(state->vgabase, VGA_PEL_D, 0);
981 		vga_w(state->vgabase, VGA_PEL_D, 0);
982 		vga_w(state->vgabase, VGA_PEL_D, 0);
983 	}
984 }
985 
986 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch)
987 {
988 	switch (blank) {
989 	case 0:		/* Unblank */
990 		if (vga_vesa_blanked) {
991 			vga_vesa_unblank(&state);
992 			vga_vesa_blanked = 0;
993 		}
994 		if (vga_palette_blanked) {
995 			vga_set_palette(c, color_table);
996 			vga_palette_blanked = 0;
997 			return 0;
998 		}
999 		vga_is_gfx = 0;
1000 		/* Tell console.c that it has to restore the screen itself */
1001 		return 1;
1002 	case 1:		/* Normal blanking */
1003 	case -1:	/* Obsolete */
1004 		if (!mode_switch && vga_video_type == VIDEO_TYPE_VGAC) {
1005 			vga_pal_blank(&state);
1006 			vga_palette_blanked = 1;
1007 			return 0;
1008 		}
1009 		vgacon_set_origin(c);
1010 		scr_memsetw((void *) vga_vram_base, BLANK,
1011 			    c->vc_screenbuf_size);
1012 		if (mode_switch)
1013 			vga_is_gfx = 1;
1014 		return 1;
1015 	default:		/* VESA blanking */
1016 		if (vga_video_type == VIDEO_TYPE_VGAC) {
1017 			vga_vesa_blank(&state, blank - 1);
1018 			vga_vesa_blanked = blank;
1019 		}
1020 		return 0;
1021 	}
1022 }
1023 
1024 /*
1025  * PIO_FONT support.
1026  *
1027  * The font loading code goes back to the codepage package by
1028  * Joel Hoffman (joel@wam.umd.edu). (He reports that the original
1029  * reference is: "From: p. 307 of _Programmer's Guide to PC & PS/2
1030  * Video Systems_ by Richard Wilton. 1987.  Microsoft Press".)
1031  *
1032  * Change for certain monochrome monitors by Yury Shevchuck
1033  * (sizif@botik.yaroslavl.su).
1034  */
1035 
1036 #ifdef CAN_LOAD_EGA_FONTS
1037 
1038 #define colourmap 0xa0000
1039 /* Pauline Middelink <middelin@polyware.iaf.nl> reports that we
1040    should use 0xA0000 for the bwmap as well.. */
1041 #define blackwmap 0xa0000
1042 #define cmapsz 8192
1043 
1044 static int vgacon_do_font_op(struct vgastate *state,char *arg,int set,int ch512)
1045 {
1046 	unsigned short video_port_status = vga_video_port_reg + 6;
1047 	int font_select = 0x00, beg, i;
1048 	char *charmap;
1049 
1050 	if (vga_video_type != VIDEO_TYPE_EGAM) {
1051 		charmap = (char *) VGA_MAP_MEM(colourmap, 0);
1052 		beg = 0x0e;
1053 #ifdef VGA_CAN_DO_64KB
1054 		if (vga_video_type == VIDEO_TYPE_VGAC)
1055 			beg = 0x06;
1056 #endif
1057 	} else {
1058 		charmap = (char *) VGA_MAP_MEM(blackwmap, 0);
1059 		beg = 0x0a;
1060 	}
1061 
1062 #ifdef BROKEN_GRAPHICS_PROGRAMS
1063 	/*
1064 	 * All fonts are loaded in slot 0 (0:1 for 512 ch)
1065 	 */
1066 
1067 	if (!arg)
1068 		return -EINVAL;	/* Return to default font not supported */
1069 
1070 	vga_font_is_default = 0;
1071 	font_select = ch512 ? 0x04 : 0x00;
1072 #else
1073 	/*
1074 	 * The default font is kept in slot 0 and is never touched.
1075 	 * A custom font is loaded in slot 2 (256 ch) or 2:3 (512 ch)
1076 	 */
1077 
1078 	if (set) {
1079 		vga_font_is_default = !arg;
1080 		if (!arg)
1081 			ch512 = 0;	/* Default font is always 256 */
1082 		font_select = arg ? (ch512 ? 0x0e : 0x0a) : 0x00;
1083 	}
1084 
1085 	if (!vga_font_is_default)
1086 		charmap += 4 * cmapsz;
1087 #endif
1088 
1089 	unlock_kernel();
1090 	spin_lock_irq(&vga_lock);
1091 	/* First, the Sequencer */
1092 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x1);
1093 	/* CPU writes only to map 2 */
1094 	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x04);
1095 	/* Sequential addressing */
1096 	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x07);
1097 	/* Clear synchronous reset */
1098 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
1099 
1100 	/* Now, the graphics controller, select map 2 */
1101 	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x02);
1102 	/* disable odd-even addressing */
1103 	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x00);
1104 	/* map start at A000:0000 */
1105 	vga_wgfx(state->vgabase, VGA_GFX_MISC, 0x00);
1106 	spin_unlock_irq(&vga_lock);
1107 
1108 	if (arg) {
1109 		if (set)
1110 			for (i = 0; i < cmapsz; i++)
1111 				vga_writeb(arg[i], charmap + i);
1112 		else
1113 			for (i = 0; i < cmapsz; i++)
1114 				arg[i] = vga_readb(charmap + i);
1115 
1116 		/*
1117 		 * In 512-character mode, the character map is not contiguous if
1118 		 * we want to remain EGA compatible -- which we do
1119 		 */
1120 
1121 		if (ch512) {
1122 			charmap += 2 * cmapsz;
1123 			arg += cmapsz;
1124 			if (set)
1125 				for (i = 0; i < cmapsz; i++)
1126 					vga_writeb(arg[i], charmap + i);
1127 			else
1128 				for (i = 0; i < cmapsz; i++)
1129 					arg[i] = vga_readb(charmap + i);
1130 		}
1131 	}
1132 
1133 	spin_lock_irq(&vga_lock);
1134 	/* First, the sequencer, Synchronous reset */
1135 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x01);
1136 	/* CPU writes to maps 0 and 1 */
1137 	vga_wseq(state->vgabase, VGA_SEQ_PLANE_WRITE, 0x03);
1138 	/* odd-even addressing */
1139 	vga_wseq(state->vgabase, VGA_SEQ_MEMORY_MODE, 0x03);
1140 	/* Character Map Select */
1141 	if (set)
1142 		vga_wseq(state->vgabase, VGA_SEQ_CHARACTER_MAP, font_select);
1143 	/* clear synchronous reset */
1144 	vga_wseq(state->vgabase, VGA_SEQ_RESET, 0x03);
1145 
1146 	/* Now, the graphics controller, select map 0 for CPU */
1147 	vga_wgfx(state->vgabase, VGA_GFX_PLANE_READ, 0x00);
1148 	/* enable even-odd addressing */
1149 	vga_wgfx(state->vgabase, VGA_GFX_MODE, 0x10);
1150 	/* map starts at b800:0 or b000:0 */
1151 	vga_wgfx(state->vgabase, VGA_GFX_MISC, beg);
1152 
1153 	/* if 512 char mode is already enabled don't re-enable it. */
1154 	if ((set) && (ch512 != vga_512_chars)) {
1155 		/* attribute controller */
1156 		for (i = 0; i < MAX_NR_CONSOLES; i++) {
1157 			struct vc_data *c = vc_cons[i].d;
1158 			if (c && c->vc_sw == &vga_con)
1159 				c->vc_hi_font_mask = ch512 ? 0x0800 : 0;
1160 		}
1161 		vga_512_chars = ch512;
1162 		/* 256-char: enable intensity bit
1163 		   512-char: disable intensity bit */
1164 		inb_p(video_port_status);	/* clear address flip-flop */
1165 		/* color plane enable register */
1166 		vga_wattr(state->vgabase, VGA_ATC_PLANE_ENABLE, ch512 ? 0x07 : 0x0f);
1167 		/* Wilton (1987) mentions the following; I don't know what
1168 		   it means, but it works, and it appears necessary */
1169 		inb_p(video_port_status);
1170 		vga_wattr(state->vgabase, VGA_AR_ENABLE_DISPLAY, 0);
1171 	}
1172 	spin_unlock_irq(&vga_lock);
1173 	lock_kernel();
1174 	return 0;
1175 }
1176 
1177 /*
1178  * Adjust the screen to fit a font of a certain height
1179  */
1180 static int vgacon_adjust_height(struct vc_data *vc, unsigned fontheight)
1181 {
1182 	unsigned char ovr, vde, fsr;
1183 	int rows, maxscan, i;
1184 
1185 	rows = vc->vc_scan_lines / fontheight;	/* Number of video rows we end up with */
1186 	maxscan = rows * fontheight - 1;	/* Scan lines to actually display-1 */
1187 
1188 	/* Reprogram the CRTC for the new font size
1189 	   Note: the attempt to read the overflow register will fail
1190 	   on an EGA, but using 0xff for the previous value appears to
1191 	   be OK for EGA text modes in the range 257-512 scan lines, so I
1192 	   guess we don't need to worry about it.
1193 
1194 	   The same applies for the spill bits in the font size and cursor
1195 	   registers; they are write-only on EGA, but it appears that they
1196 	   are all don't care bits on EGA, so I guess it doesn't matter. */
1197 
1198 	spin_lock_irq(&vga_lock);
1199 	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
1200 	ovr = inb_p(vga_video_port_val);
1201 	outb_p(0x09, vga_video_port_reg);	/* Font size register */
1202 	fsr = inb_p(vga_video_port_val);
1203 	spin_unlock_irq(&vga_lock);
1204 
1205 	vde = maxscan & 0xff;	/* Vertical display end reg */
1206 	ovr = (ovr & 0xbd) +	/* Overflow register */
1207 	    ((maxscan & 0x100) >> 7) + ((maxscan & 0x200) >> 3);
1208 	fsr = (fsr & 0xe0) + (fontheight - 1);	/*  Font size register */
1209 
1210 	spin_lock_irq(&vga_lock);
1211 	outb_p(0x07, vga_video_port_reg);	/* CRTC overflow register */
1212 	outb_p(ovr, vga_video_port_val);
1213 	outb_p(0x09, vga_video_port_reg);	/* Font size */
1214 	outb_p(fsr, vga_video_port_val);
1215 	outb_p(0x12, vga_video_port_reg);	/* Vertical display limit */
1216 	outb_p(vde, vga_video_port_val);
1217 	spin_unlock_irq(&vga_lock);
1218 	vga_video_font_height = fontheight;
1219 
1220 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
1221 		struct vc_data *c = vc_cons[i].d;
1222 
1223 		if (c && c->vc_sw == &vga_con) {
1224 			if (CON_IS_VISIBLE(c)) {
1225 			        /* void size to cause regs to be rewritten */
1226 				cursor_size_lastfrom = 0;
1227 				cursor_size_lastto = 0;
1228 				c->vc_sw->con_cursor(c, CM_DRAW);
1229 			}
1230 			c->vc_font.height = fontheight;
1231 			vc_resize(c, 0, rows);	/* Adjust console size */
1232 		}
1233 	}
1234 	return 0;
1235 }
1236 
1237 static int vgacon_font_set(struct vc_data *c, struct console_font *font, unsigned flags)
1238 {
1239 	unsigned charcount = font->charcount;
1240 	int rc;
1241 
1242 	if (vga_video_type < VIDEO_TYPE_EGAM)
1243 		return -EINVAL;
1244 
1245 	if (font->width != VGA_FONTWIDTH ||
1246 	    (charcount != 256 && charcount != 512))
1247 		return -EINVAL;
1248 
1249 	rc = vgacon_do_font_op(&state, font->data, 1, charcount == 512);
1250 	if (rc)
1251 		return rc;
1252 
1253 	if (!(flags & KD_FONT_FLAG_DONT_RECALC))
1254 		rc = vgacon_adjust_height(c, font->height);
1255 	return rc;
1256 }
1257 
1258 static int vgacon_font_get(struct vc_data *c, struct console_font *font)
1259 {
1260 	if (vga_video_type < VIDEO_TYPE_EGAM)
1261 		return -EINVAL;
1262 
1263 	font->width = VGA_FONTWIDTH;
1264 	font->height = c->vc_font.height;
1265 	font->charcount = vga_512_chars ? 512 : 256;
1266 	if (!font->data)
1267 		return 0;
1268 	return vgacon_do_font_op(&state, font->data, 0, 0);
1269 }
1270 
1271 #else
1272 
1273 #define vgacon_font_set NULL
1274 #define vgacon_font_get NULL
1275 
1276 #endif
1277 
1278 static int vgacon_resize(struct vc_data *c, unsigned int width,
1279 			 unsigned int height, unsigned int user)
1280 {
1281 	if (width % 2 || width > screen_info.orig_video_cols ||
1282 	    height > (screen_info.orig_video_lines * vga_default_font_height)/
1283 	    c->vc_font.height)
1284 		/* let svgatextmode tinker with video timings and
1285 		   return success */
1286 		return (user) ? 0 : -EINVAL;
1287 
1288 	if (CON_IS_VISIBLE(c) && !vga_is_gfx) /* who knows */
1289 		vgacon_doresize(c, width, height);
1290 	return 0;
1291 }
1292 
1293 static int vgacon_set_origin(struct vc_data *c)
1294 {
1295 	if (vga_is_gfx ||	/* We don't play origin tricks in graphic modes */
1296 	    (console_blanked && !vga_palette_blanked))	/* Nor we write to blanked screens */
1297 		return 0;
1298 	c->vc_origin = c->vc_visible_origin = vga_vram_base;
1299 	vga_set_mem_top(c);
1300 	vga_rolled_over = 0;
1301 	return 1;
1302 }
1303 
1304 static void vgacon_save_screen(struct vc_data *c)
1305 {
1306 	static int vga_bootup_console = 0;
1307 
1308 	if (!vga_bootup_console) {
1309 		/* This is a gross hack, but here is the only place we can
1310 		 * set bootup console parameters without messing up generic
1311 		 * console initialization routines.
1312 		 */
1313 		vga_bootup_console = 1;
1314 		c->vc_x = screen_info.orig_x;
1315 		c->vc_y = screen_info.orig_y;
1316 	}
1317 
1318 	/* We can't copy in more then the size of the video buffer,
1319 	 * or we'll be copying in VGA BIOS */
1320 
1321 	if (!vga_is_gfx)
1322 		scr_memcpyw((u16 *) c->vc_screenbuf, (u16 *) c->vc_origin,
1323 			    c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size);
1324 }
1325 
1326 static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
1327 			 int lines)
1328 {
1329 	unsigned long oldo;
1330 	unsigned int delta;
1331 
1332 	if (t || b != c->vc_rows || vga_is_gfx || c->vc_mode != KD_TEXT)
1333 		return 0;
1334 
1335 	if (!vga_hardscroll_enabled || lines >= c->vc_rows / 2)
1336 		return 0;
1337 
1338 	vgacon_restore_screen(c);
1339 	oldo = c->vc_origin;
1340 	delta = lines * c->vc_size_row;
1341 	if (dir == SM_UP) {
1342 		vgacon_scrollback_update(c, t, lines);
1343 		if (c->vc_scr_end + delta >= vga_vram_end) {
1344 			scr_memcpyw((u16 *) vga_vram_base,
1345 				    (u16 *) (oldo + delta),
1346 				    c->vc_screenbuf_size - delta);
1347 			c->vc_origin = vga_vram_base;
1348 			vga_rolled_over = oldo - vga_vram_base;
1349 		} else
1350 			c->vc_origin += delta;
1351 		scr_memsetw((u16 *) (c->vc_origin + c->vc_screenbuf_size -
1352 				     delta), c->vc_video_erase_char,
1353 			    delta);
1354 	} else {
1355 		if (oldo - delta < vga_vram_base) {
1356 			scr_memmovew((u16 *) (vga_vram_end -
1357 					      c->vc_screenbuf_size +
1358 					      delta), (u16 *) oldo,
1359 				     c->vc_screenbuf_size - delta);
1360 			c->vc_origin = vga_vram_end - c->vc_screenbuf_size;
1361 			vga_rolled_over = 0;
1362 		} else
1363 			c->vc_origin -= delta;
1364 		c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1365 		scr_memsetw((u16 *) (c->vc_origin), c->vc_video_erase_char,
1366 			    delta);
1367 	}
1368 	c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1369 	c->vc_visible_origin = c->vc_origin;
1370 	vga_set_mem_top(c);
1371 	c->vc_pos = (c->vc_pos - oldo) + c->vc_origin;
1372 	return 1;
1373 }
1374 
1375 
1376 /*
1377  *  The console `switch' structure for the VGA based console
1378  */
1379 
1380 static int vgacon_dummy(struct vc_data *c)
1381 {
1382 	return 0;
1383 }
1384 
1385 #define DUMMY (void *) vgacon_dummy
1386 
1387 const struct consw vga_con = {
1388 	.owner = THIS_MODULE,
1389 	.con_startup = vgacon_startup,
1390 	.con_init = vgacon_init,
1391 	.con_deinit = vgacon_deinit,
1392 	.con_clear = DUMMY,
1393 	.con_putc = DUMMY,
1394 	.con_putcs = DUMMY,
1395 	.con_cursor = vgacon_cursor,
1396 	.con_scroll = vgacon_scroll,
1397 	.con_bmove = DUMMY,
1398 	.con_switch = vgacon_switch,
1399 	.con_blank = vgacon_blank,
1400 	.con_font_set = vgacon_font_set,
1401 	.con_font_get = vgacon_font_get,
1402 	.con_resize = vgacon_resize,
1403 	.con_set_palette = vgacon_set_palette,
1404 	.con_scrolldelta = vgacon_scrolldelta,
1405 	.con_set_origin = vgacon_set_origin,
1406 	.con_save_screen = vgacon_save_screen,
1407 	.con_build_attr = vgacon_build_attr,
1408 	.con_invert_region = vgacon_invert_region,
1409 };
1410 
1411 MODULE_LICENSE("GPL");
1412