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/slab.h>
37#include <linux/vt_kern.h>
38#include <linux/vt_buffer.h>
39#include <linux/selection.h>
40#include <linux/spinlock.h>
41#include <linux/ioport.h>
42#include <linux/delay.h>
43#include <linux/init.h>
44
45#include <asm/io.h>
46#include <asm/vga.h>
47
48static DEFINE_SPINLOCK(mda_lock);
49
50/* description of the hardware layout */
51
52static unsigned long	mda_vram_base;		/* Base of video memory */
53static unsigned long	mda_vram_len;		/* Size of video memory */
54static unsigned int	mda_num_columns;	/* Number of text columns */
55static unsigned int	mda_num_lines;		/* Number of text lines */
56
57static unsigned int	mda_index_port;		/* Register select port */
58static unsigned int	mda_value_port;		/* Register value port */
59static unsigned int	mda_mode_port;		/* Mode control port */
60static unsigned int	mda_status_port;	/* Status and Config port */
61static unsigned int	mda_gfx_port;		/* Graphics control port */
62
63/* current hardware state */
64
65static int	mda_cursor_loc=-1;
66static int	mda_cursor_size_from=-1;
67static int	mda_cursor_size_to=-1;
68
69static enum { TYPE_MDA, TYPE_HERC, TYPE_HERCPLUS, TYPE_HERCCOLOR } mda_type;
70static char *mda_type_name;
71
72/* console information */
73
74static int	mda_first_vc = 1;
75static int	mda_last_vc  = 16;
76
77static struct vc_data	*mda_display_fg = NULL;
78
79module_param(mda_first_vc, int, 0);
80module_param(mda_last_vc, int, 0);
81
82/* MDA register values
83 */
84
85#define MDA_CURSOR_BLINKING	0x00
86#define MDA_CURSOR_OFF		0x20
87#define MDA_CURSOR_SLOWBLINK	0x60
88
89#define MDA_MODE_GRAPHICS	0x02
90#define MDA_MODE_VIDEO_EN	0x08
91#define MDA_MODE_BLINK_EN	0x20
92#define MDA_MODE_GFX_PAGE1	0x80
93
94#define MDA_STATUS_HSYNC	0x01
95#define MDA_STATUS_VSYNC	0x80
96#define MDA_STATUS_VIDEO	0x08
97
98#define MDA_CONFIG_COL132	0x08
99#define MDA_GFX_MODE_EN		0x01
100#define MDA_GFX_PAGE_EN		0x02
101
102
103/*
104 * MDA could easily be classified as "pre-dinosaur hardware".
105 */
106
107static void write_mda_b(unsigned int val, unsigned char reg)
108{
109	unsigned long flags;
110
111	spin_lock_irqsave(&mda_lock, flags);
112
113	outb_p(reg, mda_index_port);
114	outb_p(val, mda_value_port);
115
116	spin_unlock_irqrestore(&mda_lock, flags);
117}
118
119static void write_mda_w(unsigned int val, unsigned char reg)
120{
121	unsigned long flags;
122
123	spin_lock_irqsave(&mda_lock, flags);
124
125	outb_p(reg,   mda_index_port); outb_p(val >> 8,   mda_value_port);
126	outb_p(reg+1, mda_index_port); outb_p(val & 0xff, mda_value_port);
127
128	spin_unlock_irqrestore(&mda_lock, flags);
129}
130
131#ifdef TEST_MDA_B
132static int test_mda_b(unsigned char val, unsigned char reg)
133{
134	unsigned long flags;
135
136	spin_lock_irqsave(&mda_lock, flags);
137
138	outb_p(reg, mda_index_port);
139	outb  (val, mda_value_port);
140
141	udelay(20); val = (inb_p(mda_value_port) == val);
142
143	spin_unlock_irqrestore(&mda_lock, flags);
144	return val;
145}
146#endif
147
148static inline void mda_set_cursor(unsigned int location)
149{
150	if (mda_cursor_loc == location)
151		return;
152
153	write_mda_w(location >> 1, 0x0e);
154
155	mda_cursor_loc = location;
156}
157
158static inline void mda_set_cursor_size(int from, int to)
159{
160	if (mda_cursor_size_from==from && mda_cursor_size_to==to)
161		return;
162
163	if (from > to) {
164		write_mda_b(MDA_CURSOR_OFF, 0x0a);	/* disable cursor */
165	} else {
166		write_mda_b(from, 0x0a);	/* cursor start */
167		write_mda_b(to,   0x0b);	/* cursor end */
168	}
169
170	mda_cursor_size_from = from;
171	mda_cursor_size_to   = to;
172}
173
174
175#ifndef MODULE
176static int __init mdacon_setup(char *str)
177{
178	/* command line format: mdacon=<first>,<last> */
179
180	int ints[3];
181
182	str = get_options(str, ARRAY_SIZE(ints), ints);
183
184	if (ints[0] < 2)
185		return 0;
186
187	if (ints[1] < 1 || ints[1] > MAX_NR_CONSOLES ||
188	    ints[2] < 1 || ints[2] > MAX_NR_CONSOLES)
189		return 0;
190
191	mda_first_vc = ints[1];
192	mda_last_vc  = ints[2];
193	return 1;
194}
195
196__setup("mdacon=", mdacon_setup);
197#endif
198
199static int mda_detect(void)
200{
201	int count=0;
202	u16 *p, p_save;
203	u16 *q, q_save;
204
205	/* do a memory check */
206
207	p = (u16 *) mda_vram_base;
208	q = (u16 *) (mda_vram_base + 0x01000);
209
210	p_save = scr_readw(p); q_save = scr_readw(q);
211
212	scr_writew(0xAA55, p); if (scr_readw(p) == 0xAA55) count++;
213	scr_writew(0x55AA, p); if (scr_readw(p) == 0x55AA) count++;
214	scr_writew(p_save, p);
215
216	if (count != 2) {
217		return 0;
218	}
219
220	/* check if we have 4K or 8K */
221
222	scr_writew(0xA55A, q); scr_writew(0x0000, p);
223	if (scr_readw(q) == 0xA55A) count++;
224
225	scr_writew(0x5AA5, q); scr_writew(0x0000, p);
226	if (scr_readw(q) == 0x5AA5) count++;
227
228	scr_writew(p_save, p); scr_writew(q_save, q);
229
230	if (count == 4) {
231		mda_vram_len = 0x02000;
232	}
233
234	/* Ok, there is definitely a card registering at the correct
235	 * memory location, so now we do an I/O port test.
236	 */
237
238#ifdef TEST_MDA_B
239	/* Edward: These two mess `tests' mess up my cursor on bootup */
240
241	/* cursor low register */
242	if (! test_mda_b(0x66, 0x0f)) {
243		return 0;
244	}
245
246	/* cursor low register */
247	if (! test_mda_b(0x99, 0x0f)) {
248		return 0;
249	}
250#endif
251
252	/* See if the card is a Hercules, by checking whether the vsync
253	 * bit of the status register is changing.  This test lasts for
254	 * approximately 1/10th of a second.
255	 */
256
257	p_save = q_save = inb_p(mda_status_port) & MDA_STATUS_VSYNC;
258
259	for (count=0; count < 50000 && p_save == q_save; count++) {
260		q_save = inb(mda_status_port) & MDA_STATUS_VSYNC;
261		udelay(2);
262	}
263
264	if (p_save != q_save) {
265		switch (inb_p(mda_status_port) & 0x70) {
266			case 0x10:
267				mda_type = TYPE_HERCPLUS;
268				mda_type_name = "HerculesPlus";
269				break;
270			case 0x50:
271				mda_type = TYPE_HERCCOLOR;
272				mda_type_name = "HerculesColor";
273				break;
274			default:
275				mda_type = TYPE_HERC;
276				mda_type_name = "Hercules";
277				break;
278		}
279	}
280
281	return 1;
282}
283
284static void mda_initialize(void)
285{
286	write_mda_b(97, 0x00);		/* horizontal total */
287	write_mda_b(80, 0x01);		/* horizontal displayed */
288	write_mda_b(82, 0x02);		/* horizontal sync pos */
289	write_mda_b(15, 0x03);		/* horizontal sync width */
290
291	write_mda_b(25, 0x04);		/* vertical total */
292	write_mda_b(6,  0x05);		/* vertical total adjust */
293	write_mda_b(25, 0x06);		/* vertical displayed */
294	write_mda_b(25, 0x07);		/* vertical sync pos */
295
296	write_mda_b(2,  0x08);		/* interlace mode */
297	write_mda_b(13, 0x09);		/* maximum scanline */
298	write_mda_b(12, 0x0a);		/* cursor start */
299	write_mda_b(13, 0x0b);		/* cursor end */
300
301	write_mda_w(0x0000, 0x0c);	/* start address */
302	write_mda_w(0x0000, 0x0e);	/* cursor location */
303
304	outb_p(MDA_MODE_VIDEO_EN | MDA_MODE_BLINK_EN, mda_mode_port);
305	outb_p(0x00, mda_status_port);
306	outb_p(0x00, mda_gfx_port);
307}
308
309static const char *mdacon_startup(void)
310{
311	mda_num_columns = 80;
312	mda_num_lines   = 25;
313
314	mda_vram_len  = 0x01000;
315	mda_vram_base = VGA_MAP_MEM(0xb0000, mda_vram_len);
316
317	mda_index_port  = 0x3b4;
318	mda_value_port  = 0x3b5;
319	mda_mode_port   = 0x3b8;
320	mda_status_port = 0x3ba;
321	mda_gfx_port    = 0x3bf;
322
323	mda_type = TYPE_MDA;
324	mda_type_name = "MDA";
325
326	if (! mda_detect()) {
327		printk("mdacon: MDA card not detected.\n");
328		return NULL;
329	}
330
331	if (mda_type != TYPE_MDA) {
332		mda_initialize();
333	}
334
335	/* cursor looks ugly during boot-up, so turn it off */
336	mda_set_cursor(mda_vram_len - 1);
337
338	printk("mdacon: %s with %ldK of memory detected.\n",
339		mda_type_name, mda_vram_len/1024);
340
341	return "MDA-2";
342}
343
344static void mdacon_init(struct vc_data *c, int init)
345{
346	c->vc_complement_mask = 0x0800;	 /* reverse video */
347	c->vc_display_fg = &mda_display_fg;
348
349	if (init) {
350		c->vc_cols = mda_num_columns;
351		c->vc_rows = mda_num_lines;
352	} else
353		vc_resize(c, mda_num_columns, mda_num_lines);
354
355	/* make the first MDA console visible */
356
357	if (mda_display_fg == NULL)
358		mda_display_fg = c;
359}
360
361static void mdacon_deinit(struct vc_data *c)
362{
363	/* con_set_default_unimap(c->vc_num); */
364
365	if (mda_display_fg == c)
366		mda_display_fg = NULL;
367}
368
369static inline u16 mda_convert_attr(u16 ch)
370{
371	u16 attr = 0x0700;
372
373	/* Underline and reverse-video are mutually exclusive on MDA.
374	 * Since reverse-video is used for cursors and selected areas,
375	 * it takes precedence.
376	 */
377
378	if (ch & 0x0800)	attr = 0x7000;	/* reverse */
379	else if (ch & 0x0400)	attr = 0x0100;	/* underline */
380
381	return ((ch & 0x0200) << 2) | 		/* intensity */
382		(ch & 0x8000) |			/* blink */
383		(ch & 0x00ff) | attr;
384}
385
386static u8 mdacon_build_attr(struct vc_data *c, u8 color, u8 intensity,
387			    u8 blink, u8 underline, u8 reverse, u8 italic)
388{
389	/* The attribute is just a bit vector:
390	 *
391	 *	Bit 0..1 : intensity (0..2)
392	 *	Bit 2    : underline
393	 *	Bit 3    : reverse
394	 *	Bit 7    : blink
395	 */
396
397	return (intensity & 3) |
398		((underline & 1) << 2) |
399		((reverse   & 1) << 3) |
400		(!!italic << 4) |
401		((blink     & 1) << 7);
402}
403
404static void mdacon_invert_region(struct vc_data *c, u16 *p, int count)
405{
406	for (; count > 0; count--) {
407		scr_writew(scr_readw(p) ^ 0x0800, p);
408		p++;
409	}
410}
411
412#define MDA_ADDR(x,y)  ((u16 *) mda_vram_base + (y)*mda_num_columns + (x))
413
414static void mdacon_putc(struct vc_data *c, int ch, int y, int x)
415{
416	scr_writew(mda_convert_attr(ch), MDA_ADDR(x, y));
417}
418
419static void mdacon_putcs(struct vc_data *c, const unsigned short *s,
420		         int count, int y, int x)
421{
422	u16 *dest = MDA_ADDR(x, y);
423
424	for (; count > 0; count--) {
425		scr_writew(mda_convert_attr(scr_readw(s++)), dest++);
426	}
427}
428
429static void mdacon_clear(struct vc_data *c, int y, int x,
430			  int height, int width)
431{
432	u16 *dest = MDA_ADDR(x, y);
433	u16 eattr = mda_convert_attr(c->vc_video_erase_char);
434
435	if (width <= 0 || height <= 0)
436		return;
437
438	if (x==0 && width==mda_num_columns) {
439		scr_memsetw(dest, eattr, height*width*2);
440	} else {
441		for (; height > 0; height--, dest+=mda_num_columns)
442			scr_memsetw(dest, eattr, width*2);
443	}
444}
445
446static void mdacon_bmove(struct vc_data *c, int sy, int sx,
447			 int dy, int dx, int height, int width)
448{
449	u16 *src, *dest;
450
451	if (width <= 0 || height <= 0)
452		return;
453
454	if (sx==0 && dx==0 && width==mda_num_columns) {
455		scr_memmovew(MDA_ADDR(0,dy), MDA_ADDR(0,sy), height*width*2);
456
457	} else if (dy < sy || (dy == sy && dx < sx)) {
458		src  = MDA_ADDR(sx, sy);
459		dest = MDA_ADDR(dx, dy);
460
461		for (; height > 0; height--) {
462			scr_memmovew(dest, src, width*2);
463			src  += mda_num_columns;
464			dest += mda_num_columns;
465		}
466	} else {
467		src  = MDA_ADDR(sx, sy+height-1);
468		dest = MDA_ADDR(dx, dy+height-1);
469
470		for (; height > 0; height--) {
471			scr_memmovew(dest, src, width*2);
472			src  -= mda_num_columns;
473			dest -= mda_num_columns;
474		}
475	}
476}
477
478static int mdacon_switch(struct vc_data *c)
479{
480	return 1;	/* redrawing needed */
481}
482
483static int mdacon_set_palette(struct vc_data *c, unsigned char *table)
484{
485	return -EINVAL;
486}
487
488static int mdacon_blank(struct vc_data *c, int blank, int mode_switch)
489{
490	if (mda_type == TYPE_MDA) {
491		if (blank)
492			scr_memsetw((void *)mda_vram_base,
493				mda_convert_attr(c->vc_video_erase_char),
494				c->vc_screenbuf_size);
495		/* Tell console.c that it has to restore the screen itself */
496		return 1;
497	} else {
498		if (blank)
499			outb_p(0x00, mda_mode_port);	/* disable video */
500		else
501			outb_p(MDA_MODE_VIDEO_EN | MDA_MODE_BLINK_EN,
502				mda_mode_port);
503		return 0;
504	}
505}
506
507static int mdacon_scrolldelta(struct vc_data *c, int lines)
508{
509	return 0;
510}
511
512static void mdacon_cursor(struct vc_data *c, int mode)
513{
514	if (mode == CM_ERASE) {
515		mda_set_cursor(mda_vram_len - 1);
516		return;
517	}
518
519	mda_set_cursor(c->vc_y*mda_num_columns*2 + c->vc_x*2);
520
521	switch (c->vc_cursor_type & 0x0f) {
522
523		case CUR_LOWER_THIRD:	mda_set_cursor_size(10, 13); break;
524		case CUR_LOWER_HALF:	mda_set_cursor_size(7,  13); break;
525		case CUR_TWO_THIRDS:	mda_set_cursor_size(4,  13); break;
526		case CUR_BLOCK:		mda_set_cursor_size(1,  13); break;
527		case CUR_NONE:		mda_set_cursor_size(14, 13); break;
528		default:		mda_set_cursor_size(12, 13); break;
529	}
530}
531
532static int mdacon_scroll(struct vc_data *c, int t, int b, int dir, int lines)
533{
534	u16 eattr = mda_convert_attr(c->vc_video_erase_char);
535
536	if (!lines)
537		return 0;
538
539	if (lines > c->vc_rows)   /* maximum realistic size */
540		lines = c->vc_rows;
541
542	switch (dir) {
543
544	case SM_UP:
545		scr_memmovew(MDA_ADDR(0,t), MDA_ADDR(0,t+lines),
546				(b-t-lines)*mda_num_columns*2);
547		scr_memsetw(MDA_ADDR(0,b-lines), eattr,
548				lines*mda_num_columns*2);
549		break;
550
551	case SM_DOWN:
552		scr_memmovew(MDA_ADDR(0,t+lines), MDA_ADDR(0,t),
553				(b-t-lines)*mda_num_columns*2);
554		scr_memsetw(MDA_ADDR(0,t), eattr, lines*mda_num_columns*2);
555		break;
556	}
557
558	return 0;
559}
560
561
562/*
563 *  The console `switch' structure for the MDA based console
564 */
565
566static const struct consw mda_con = {
567	.owner =		THIS_MODULE,
568	.con_startup =		mdacon_startup,
569	.con_init =		mdacon_init,
570	.con_deinit =		mdacon_deinit,
571	.con_clear =		mdacon_clear,
572	.con_putc =		mdacon_putc,
573	.con_putcs =		mdacon_putcs,
574	.con_cursor =		mdacon_cursor,
575	.con_scroll =		mdacon_scroll,
576	.con_bmove =		mdacon_bmove,
577	.con_switch =		mdacon_switch,
578	.con_blank =		mdacon_blank,
579	.con_set_palette =	mdacon_set_palette,
580	.con_scrolldelta =	mdacon_scrolldelta,
581	.con_build_attr =	mdacon_build_attr,
582	.con_invert_region =	mdacon_invert_region,
583};
584
585int __init mda_console_init(void)
586{
587	if (mda_first_vc > mda_last_vc)
588		return 1;
589
590	return take_over_console(&mda_con, mda_first_vc-1, mda_last_vc-1, 0);
591}
592
593static void __exit mda_console_exit(void)
594{
595	give_up_console(&mda_con);
596}
597
598module_init(mda_console_init);
599module_exit(mda_console_exit);
600
601MODULE_LICENSE("GPL");
602