xref: /openbmc/linux/drivers/video/console/mdacon.c (revision d3964221)
1 /*
2  *  linux/drivers/video/mdacon.c -- Low level MDA based console driver
3  *
4  *	(c) 1998 Andrew Apted <ajapted@netspace.net.au>
5  *
6  *      including portions (c) 1995-1998 Patrick Caulfield.
7  *
8  *      slight improvements (c) 2000 Edward Betts <edward@debian.org>
9  *
10  *  This file is based on the VGA console driver (vgacon.c):
11  *
12  *	Created 28 Sep 1997 by Geert Uytterhoeven
13  *
14  *	Rewritten by Martin Mares <mj@ucw.cz>, July 1998
15  *
16  *  and on the old console.c, vga.c and vesa_blank.c drivers:
17  *
18  *	Copyright (C) 1991, 1992  Linus Torvalds
19  *			    1995  Jay Estabrook
20  *
21  *  This file is subject to the terms and conditions of the GNU General Public
22  *  License.  See the file COPYING in the main directory of this archive for
23  *  more details.
24  *
25  *  Changelog:
26  *  Paul G. (03/2001) Fix mdacon= boot prompt to use __setup().
27  */
28 
29 #include <linux/types.h>
30 #include <linux/fs.h>
31 #include <linux/kernel.h>
32 #include <linux/module.h>
33 #include <linux/console.h>
34 #include <linux/string.h>
35 #include <linux/kd.h>
36 #include <linux/vt_kern.h>
37 #include <linux/vt_buffer.h>
38 #include <linux/selection.h>
39 #include <linux/spinlock.h>
40 #include <linux/ioport.h>
41 #include <linux/delay.h>
42 #include <linux/init.h>
43 
44 #include <asm/io.h>
45 #include <asm/vga.h>
46 
47 static DEFINE_SPINLOCK(mda_lock);
48 
49 /* description of the hardware layout */
50 
51 static u16		*mda_vram_base;		/* Base of video memory */
52 static unsigned long	mda_vram_len;		/* Size of video memory */
53 static unsigned int	mda_num_columns;	/* Number of text columns */
54 static unsigned int	mda_num_lines;		/* Number of text lines */
55 
56 static unsigned int	mda_index_port;		/* Register select port */
57 static unsigned int	mda_value_port;		/* Register value port */
58 static unsigned int	mda_mode_port;		/* Mode control port */
59 static unsigned int	mda_status_port;	/* Status and Config port */
60 static unsigned int	mda_gfx_port;		/* Graphics control port */
61 
62 /* current hardware state */
63 
64 static int	mda_cursor_loc=-1;
65 static int	mda_cursor_size_from=-1;
66 static int	mda_cursor_size_to=-1;
67 
68 static enum { TYPE_MDA, TYPE_HERC, TYPE_HERCPLUS, TYPE_HERCCOLOR } mda_type;
69 static char *mda_type_name;
70 
71 /* console information */
72 
73 static int	mda_first_vc = 13;
74 static int	mda_last_vc  = 16;
75 
76 static struct vc_data	*mda_display_fg = NULL;
77 
78 module_param(mda_first_vc, int, 0);
79 MODULE_PARM_DESC(mda_first_vc, "First virtual console. Default: 13");
80 module_param(mda_last_vc, int, 0);
81 MODULE_PARM_DESC(mda_last_vc, "Last virtual console. Default: 16");
82 
83 /* MDA register values
84  */
85 
86 #define MDA_CURSOR_BLINKING	0x00
87 #define MDA_CURSOR_OFF		0x20
88 #define MDA_CURSOR_SLOWBLINK	0x60
89 
90 #define MDA_MODE_GRAPHICS	0x02
91 #define MDA_MODE_VIDEO_EN	0x08
92 #define MDA_MODE_BLINK_EN	0x20
93 #define MDA_MODE_GFX_PAGE1	0x80
94 
95 #define MDA_STATUS_HSYNC	0x01
96 #define MDA_STATUS_VSYNC	0x80
97 #define MDA_STATUS_VIDEO	0x08
98 
99 #define MDA_CONFIG_COL132	0x08
100 #define MDA_GFX_MODE_EN		0x01
101 #define MDA_GFX_PAGE_EN		0x02
102 
103 
104 /*
105  * MDA could easily be classified as "pre-dinosaur hardware".
106  */
107 
108 static void write_mda_b(unsigned int val, unsigned char reg)
109 {
110 	unsigned long flags;
111 
112 	spin_lock_irqsave(&mda_lock, flags);
113 
114 	outb_p(reg, mda_index_port);
115 	outb_p(val, mda_value_port);
116 
117 	spin_unlock_irqrestore(&mda_lock, flags);
118 }
119 
120 static void write_mda_w(unsigned int val, unsigned char reg)
121 {
122 	unsigned long flags;
123 
124 	spin_lock_irqsave(&mda_lock, flags);
125 
126 	outb_p(reg,   mda_index_port); outb_p(val >> 8,   mda_value_port);
127 	outb_p(reg+1, mda_index_port); outb_p(val & 0xff, mda_value_port);
128 
129 	spin_unlock_irqrestore(&mda_lock, flags);
130 }
131 
132 #ifdef TEST_MDA_B
133 static int test_mda_b(unsigned char val, unsigned char reg)
134 {
135 	unsigned long flags;
136 
137 	spin_lock_irqsave(&mda_lock, flags);
138 
139 	outb_p(reg, mda_index_port);
140 	outb  (val, mda_value_port);
141 
142 	udelay(20); val = (inb_p(mda_value_port) == val);
143 
144 	spin_unlock_irqrestore(&mda_lock, flags);
145 	return val;
146 }
147 #endif
148 
149 static inline void mda_set_cursor(unsigned int location)
150 {
151 	if (mda_cursor_loc == location)
152 		return;
153 
154 	write_mda_w(location >> 1, 0x0e);
155 
156 	mda_cursor_loc = location;
157 }
158 
159 static inline void mda_set_cursor_size(int from, int to)
160 {
161 	if (mda_cursor_size_from==from && mda_cursor_size_to==to)
162 		return;
163 
164 	if (from > to) {
165 		write_mda_b(MDA_CURSOR_OFF, 0x0a);	/* disable cursor */
166 	} else {
167 		write_mda_b(from, 0x0a);	/* cursor start */
168 		write_mda_b(to,   0x0b);	/* cursor end */
169 	}
170 
171 	mda_cursor_size_from = from;
172 	mda_cursor_size_to   = to;
173 }
174 
175 
176 #ifndef MODULE
177 static int __init mdacon_setup(char *str)
178 {
179 	/* command line format: mdacon=<first>,<last> */
180 
181 	int ints[3];
182 
183 	str = get_options(str, ARRAY_SIZE(ints), ints);
184 
185 	if (ints[0] < 2)
186 		return 0;
187 
188 	if (ints[1] < 1 || ints[1] > MAX_NR_CONSOLES ||
189 	    ints[2] < 1 || ints[2] > MAX_NR_CONSOLES)
190 		return 0;
191 
192 	mda_first_vc = ints[1];
193 	mda_last_vc  = ints[2];
194 	return 1;
195 }
196 
197 __setup("mdacon=", mdacon_setup);
198 #endif
199 
200 static int mda_detect(void)
201 {
202 	int count=0;
203 	u16 *p, p_save;
204 	u16 *q, q_save;
205 
206 	/* do a memory check */
207 
208 	p = mda_vram_base;
209 	q = mda_vram_base + 0x01000 / 2;
210 
211 	p_save = scr_readw(p);
212 	q_save = scr_readw(q);
213 
214 	scr_writew(0xAA55, p);
215 	if (scr_readw(p) == 0xAA55)
216 		count++;
217 
218 	scr_writew(0x55AA, p);
219 	if (scr_readw(p) == 0x55AA)
220 		count++;
221 
222 	scr_writew(p_save, p);
223 
224 	if (count != 2) {
225 		return 0;
226 	}
227 
228 	/* check if we have 4K or 8K */
229 
230 	scr_writew(0xA55A, q);
231 	scr_writew(0x0000, p);
232 	if (scr_readw(q) == 0xA55A)
233 		count++;
234 
235 	scr_writew(0x5AA5, q);
236 	scr_writew(0x0000, p);
237 	if (scr_readw(q) == 0x5AA5)
238 		count++;
239 
240 	scr_writew(p_save, p);
241 	scr_writew(q_save, q);
242 
243 	if (count == 4) {
244 		mda_vram_len = 0x02000;
245 	}
246 
247 	/* Ok, there is definitely a card registering at the correct
248 	 * memory location, so now we do an I/O port test.
249 	 */
250 
251 #ifdef TEST_MDA_B
252 	/* Edward: These two mess `tests' mess up my cursor on bootup */
253 
254 	/* cursor low register */
255 	if (!test_mda_b(0x66, 0x0f))
256 		return 0;
257 
258 	/* cursor low register */
259 	if (!test_mda_b(0x99, 0x0f))
260 		return 0;
261 #endif
262 
263 	/* See if the card is a Hercules, by checking whether the vsync
264 	 * bit of the status register is changing.  This test lasts for
265 	 * approximately 1/10th of a second.
266 	 */
267 
268 	p_save = q_save = inb_p(mda_status_port) & MDA_STATUS_VSYNC;
269 
270 	for (count = 0; count < 50000 && p_save == q_save; count++) {
271 		q_save = inb(mda_status_port) & MDA_STATUS_VSYNC;
272 		udelay(2);
273 	}
274 
275 	if (p_save != q_save) {
276 		switch (inb_p(mda_status_port) & 0x70) {
277 		case 0x10:
278 			mda_type = TYPE_HERCPLUS;
279 			mda_type_name = "HerculesPlus";
280 			break;
281 		case 0x50:
282 			mda_type = TYPE_HERCCOLOR;
283 			mda_type_name = "HerculesColor";
284 			break;
285 		default:
286 			mda_type = TYPE_HERC;
287 			mda_type_name = "Hercules";
288 			break;
289 		}
290 	}
291 
292 	return 1;
293 }
294 
295 static void mda_initialize(void)
296 {
297 	write_mda_b(97, 0x00);		/* horizontal total */
298 	write_mda_b(80, 0x01);		/* horizontal displayed */
299 	write_mda_b(82, 0x02);		/* horizontal sync pos */
300 	write_mda_b(15, 0x03);		/* horizontal sync width */
301 
302 	write_mda_b(25, 0x04);		/* vertical total */
303 	write_mda_b(6,  0x05);		/* vertical total adjust */
304 	write_mda_b(25, 0x06);		/* vertical displayed */
305 	write_mda_b(25, 0x07);		/* vertical sync pos */
306 
307 	write_mda_b(2,  0x08);		/* interlace mode */
308 	write_mda_b(13, 0x09);		/* maximum scanline */
309 	write_mda_b(12, 0x0a);		/* cursor start */
310 	write_mda_b(13, 0x0b);		/* cursor end */
311 
312 	write_mda_w(0x0000, 0x0c);	/* start address */
313 	write_mda_w(0x0000, 0x0e);	/* cursor location */
314 
315 	outb_p(MDA_MODE_VIDEO_EN | MDA_MODE_BLINK_EN, mda_mode_port);
316 	outb_p(0x00, mda_status_port);
317 	outb_p(0x00, mda_gfx_port);
318 }
319 
320 static const char *mdacon_startup(void)
321 {
322 	mda_num_columns = 80;
323 	mda_num_lines   = 25;
324 
325 	mda_vram_len  = 0x01000;
326 	mda_vram_base = (u16 *)VGA_MAP_MEM(0xb0000, mda_vram_len);
327 
328 	mda_index_port  = 0x3b4;
329 	mda_value_port  = 0x3b5;
330 	mda_mode_port   = 0x3b8;
331 	mda_status_port = 0x3ba;
332 	mda_gfx_port    = 0x3bf;
333 
334 	mda_type = TYPE_MDA;
335 	mda_type_name = "MDA";
336 
337 	if (! mda_detect()) {
338 		printk("mdacon: MDA card not detected.\n");
339 		return NULL;
340 	}
341 
342 	if (mda_type != TYPE_MDA) {
343 		mda_initialize();
344 	}
345 
346 	/* cursor looks ugly during boot-up, so turn it off */
347 	mda_set_cursor(mda_vram_len - 1);
348 
349 	printk("mdacon: %s with %ldK of memory detected.\n",
350 		mda_type_name, mda_vram_len/1024);
351 
352 	return "MDA-2";
353 }
354 
355 static void mdacon_init(struct vc_data *c, int init)
356 {
357 	c->vc_complement_mask = 0x0800;	 /* reverse video */
358 	c->vc_display_fg = &mda_display_fg;
359 
360 	if (init) {
361 		c->vc_cols = mda_num_columns;
362 		c->vc_rows = mda_num_lines;
363 	} else
364 		vc_resize(c, mda_num_columns, mda_num_lines);
365 
366 	/* make the first MDA console visible */
367 
368 	if (mda_display_fg == NULL)
369 		mda_display_fg = c;
370 }
371 
372 static void mdacon_deinit(struct vc_data *c)
373 {
374 	/* con_set_default_unimap(c->vc_num); */
375 
376 	if (mda_display_fg == c)
377 		mda_display_fg = NULL;
378 }
379 
380 static inline u16 mda_convert_attr(u16 ch)
381 {
382 	u16 attr = 0x0700;
383 
384 	/* Underline and reverse-video are mutually exclusive on MDA.
385 	 * Since reverse-video is used for cursors and selected areas,
386 	 * it takes precedence.
387 	 */
388 
389 	if (ch & 0x0800)	attr = 0x7000;	/* reverse */
390 	else if (ch & 0x0400)	attr = 0x0100;	/* underline */
391 
392 	return ((ch & 0x0200) << 2) | 		/* intensity */
393 		(ch & 0x8000) |			/* blink */
394 		(ch & 0x00ff) | attr;
395 }
396 
397 static u8 mdacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
398 			    u8 blink, u8 underline, u8 reverse, u8 italic)
399 {
400 	/* The attribute is just a bit vector:
401 	 *
402 	 *	Bit 0..1 : intensity (0..2)
403 	 *	Bit 2    : underline
404 	 *	Bit 3    : reverse
405 	 *	Bit 7    : blink
406 	 */
407 
408 	return (intensity & 3) |
409 		((underline & 1) << 2) |
410 		((reverse   & 1) << 3) |
411 		(!!italic << 4) |
412 		((blink     & 1) << 7);
413 }
414 
415 static void mdacon_invert_region(struct vc_data *c, u16 *p, int count)
416 {
417 	for (; count > 0; count--) {
418 		scr_writew(scr_readw(p) ^ 0x0800, p);
419 		p++;
420 	}
421 }
422 
423 static inline u16 *mda_addr(unsigned int x, unsigned int y)
424 {
425 	return mda_vram_base + y * mda_num_columns + x;
426 }
427 
428 static void mdacon_putc(struct vc_data *c, int ch, int y, int x)
429 {
430 	scr_writew(mda_convert_attr(ch), mda_addr(x, y));
431 }
432 
433 static void mdacon_putcs(struct vc_data *c, const unsigned short *s,
434 		         int count, int y, int x)
435 {
436 	u16 *dest = mda_addr(x, y);
437 
438 	for (; count > 0; count--) {
439 		scr_writew(mda_convert_attr(scr_readw(s++)), dest++);
440 	}
441 }
442 
443 static void mdacon_clear(struct vc_data *c, int y, int x,
444 			  int height, int width)
445 {
446 	u16 *dest = mda_addr(x, y);
447 	u16 eattr = mda_convert_attr(c->vc_video_erase_char);
448 
449 	if (width <= 0 || height <= 0)
450 		return;
451 
452 	if (x==0 && width==mda_num_columns) {
453 		scr_memsetw(dest, eattr, height*width*2);
454 	} else {
455 		for (; height > 0; height--, dest+=mda_num_columns)
456 			scr_memsetw(dest, eattr, width*2);
457 	}
458 }
459 
460 static int mdacon_switch(struct vc_data *c)
461 {
462 	return 1;	/* redrawing needed */
463 }
464 
465 static int mdacon_blank(struct vc_data *c, int blank, int mode_switch)
466 {
467 	if (mda_type == TYPE_MDA) {
468 		if (blank)
469 			scr_memsetw(mda_vram_base,
470 				mda_convert_attr(c->vc_video_erase_char),
471 				c->vc_screenbuf_size);
472 		/* Tell console.c that it has to restore the screen itself */
473 		return 1;
474 	} else {
475 		if (blank)
476 			outb_p(0x00, mda_mode_port);	/* disable video */
477 		else
478 			outb_p(MDA_MODE_VIDEO_EN | MDA_MODE_BLINK_EN,
479 				mda_mode_port);
480 		return 0;
481 	}
482 }
483 
484 static void mdacon_cursor(struct vc_data *c, int mode)
485 {
486 	if (mode == CM_ERASE) {
487 		mda_set_cursor(mda_vram_len - 1);
488 		return;
489 	}
490 
491 	mda_set_cursor(c->vc_y*mda_num_columns*2 + c->vc_x*2);
492 
493 	switch (c->vc_cursor_type & 0x0f) {
494 
495 		case CUR_LOWER_THIRD:	mda_set_cursor_size(10, 13); break;
496 		case CUR_LOWER_HALF:	mda_set_cursor_size(7,  13); break;
497 		case CUR_TWO_THIRDS:	mda_set_cursor_size(4,  13); break;
498 		case CUR_BLOCK:		mda_set_cursor_size(1,  13); break;
499 		case CUR_NONE:		mda_set_cursor_size(14, 13); break;
500 		default:		mda_set_cursor_size(12, 13); break;
501 	}
502 }
503 
504 static bool mdacon_scroll(struct vc_data *c, unsigned int t, unsigned int b,
505 		enum con_scroll dir, unsigned int lines)
506 {
507 	u16 eattr = mda_convert_attr(c->vc_video_erase_char);
508 
509 	if (!lines)
510 		return false;
511 
512 	if (lines > c->vc_rows)   /* maximum realistic size */
513 		lines = c->vc_rows;
514 
515 	switch (dir) {
516 
517 	case SM_UP:
518 		scr_memmovew(mda_addr(0, t), mda_addr(0, t + lines),
519 				(b-t-lines)*mda_num_columns*2);
520 		scr_memsetw(mda_addr(0, b - lines), eattr,
521 				lines*mda_num_columns*2);
522 		break;
523 
524 	case SM_DOWN:
525 		scr_memmovew(mda_addr(0, t + lines), mda_addr(0, t),
526 				(b-t-lines)*mda_num_columns*2);
527 		scr_memsetw(mda_addr(0, t), eattr, lines*mda_num_columns*2);
528 		break;
529 	}
530 
531 	return false;
532 }
533 
534 
535 /*
536  *  The console `switch' structure for the MDA based console
537  */
538 
539 static const struct consw mda_con = {
540 	.owner =		THIS_MODULE,
541 	.con_startup =		mdacon_startup,
542 	.con_init =		mdacon_init,
543 	.con_deinit =		mdacon_deinit,
544 	.con_clear =		mdacon_clear,
545 	.con_putc =		mdacon_putc,
546 	.con_putcs =		mdacon_putcs,
547 	.con_cursor =		mdacon_cursor,
548 	.con_scroll =		mdacon_scroll,
549 	.con_switch =		mdacon_switch,
550 	.con_blank =		mdacon_blank,
551 	.con_build_attr =	mdacon_build_attr,
552 	.con_invert_region =	mdacon_invert_region,
553 };
554 
555 int __init mda_console_init(void)
556 {
557 	int err;
558 
559 	if (mda_first_vc > mda_last_vc)
560 		return 1;
561 	console_lock();
562 	err = do_take_over_console(&mda_con, mda_first_vc-1, mda_last_vc-1, 0);
563 	console_unlock();
564 	return err;
565 }
566 
567 static void __exit mda_console_exit(void)
568 {
569 	give_up_console(&mda_con);
570 }
571 
572 module_init(mda_console_init);
573 module_exit(mda_console_exit);
574 
575 MODULE_LICENSE("GPL");
576 
577