xref: /freebsd/sys/dev/vt/hw/vga/vt_vga.c (revision 734e82fe33aa764367791a7d603b383996c6b40b)
1 /*-
2  * Copyright (c) 2005 Marcel Moolenaar
3  * All rights reserved.
4  *
5  * Copyright (c) 2009 The FreeBSD Foundation
6  * All rights reserved.
7  *
8  * Portions of this software were developed by Ed Schouten
9  * under sponsorship from the FreeBSD Foundation.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include "opt_acpi.h"
34 
35 #include <sys/cdefs.h>
36 #include <sys/param.h>
37 #include <sys/kernel.h>
38 #include <sys/systm.h>
39 #include <sys/bus.h>
40 #include <sys/module.h>
41 #include <sys/rman.h>
42 
43 #include <dev/vt/vt.h>
44 #include <dev/vt/colors/vt_termcolors.h>
45 #include <dev/vt/hw/vga/vt_vga_reg.h>
46 #include <dev/pci/pcivar.h>
47 
48 #include <machine/bus.h>
49 #if defined(__amd64__) || defined(__i386__)
50 #include <contrib/dev/acpica/include/acpi.h>
51 #include <machine/md_var.h>
52 #endif
53 
54 struct vga_softc {
55 	bus_space_tag_t		 vga_fb_tag;
56 	bus_space_handle_t	 vga_fb_handle;
57 	bus_space_tag_t		 vga_reg_tag;
58 	bus_space_handle_t	 vga_reg_handle;
59 	int			 vga_wmode;
60 	term_color_t		 vga_curfg, vga_curbg;
61 	boolean_t		 vga_enabled;
62 };
63 
64 /* Convenience macros. */
65 #define	MEM_READ1(sc, ofs) \
66 	bus_space_read_1(sc->vga_fb_tag, sc->vga_fb_handle, ofs)
67 #define	MEM_WRITE1(sc, ofs, val) \
68 	bus_space_write_1(sc->vga_fb_tag, sc->vga_fb_handle, ofs, val)
69 #define	MEM_WRITE2(sc, ofs, val) \
70 	bus_space_write_2(sc->vga_fb_tag, sc->vga_fb_handle, ofs, val)
71 #define	REG_READ1(sc, reg) \
72 	bus_space_read_1(sc->vga_reg_tag, sc->vga_reg_handle, reg)
73 #define	REG_WRITE1(sc, reg, val) \
74 	bus_space_write_1(sc->vga_reg_tag, sc->vga_reg_handle, reg, val)
75 
76 #define	VT_VGA_WIDTH	640
77 #define	VT_VGA_HEIGHT	480
78 #define	VT_VGA_MEMSIZE	(VT_VGA_WIDTH * VT_VGA_HEIGHT / 8)
79 
80 /*
81  * VGA is designed to handle 8 pixels at a time (8 pixels in one byte of
82  * memory).
83  */
84 #define	VT_VGA_PIXELS_BLOCK	8
85 
86 /*
87  * We use an off-screen addresses to:
88  *     o  store the background color;
89  *     o  store pixels pattern.
90  * Those addresses are then loaded in the latches once.
91  */
92 #define	VT_VGA_BGCOLOR_OFFSET	VT_VGA_MEMSIZE
93 
94 static vd_probe_t	vga_probe;
95 static vd_init_t	vga_init;
96 static vd_blank_t	vga_blank;
97 static vd_bitblt_text_t	vga_bitblt_text;
98 static vd_invalidate_text_t	vga_invalidate_text;
99 static vd_bitblt_bmp_t	vga_bitblt_bitmap;
100 static vd_drawrect_t	vga_drawrect;
101 static vd_setpixel_t	vga_setpixel;
102 static vd_postswitch_t	vga_postswitch;
103 
104 static const struct vt_driver vt_vga_driver = {
105 	.vd_name	= "vga",
106 	.vd_probe	= vga_probe,
107 	.vd_init	= vga_init,
108 	.vd_blank	= vga_blank,
109 	.vd_bitblt_text	= vga_bitblt_text,
110 	.vd_invalidate_text = vga_invalidate_text,
111 	.vd_bitblt_bmp	= vga_bitblt_bitmap,
112 	.vd_drawrect	= vga_drawrect,
113 	.vd_setpixel	= vga_setpixel,
114 	.vd_postswitch	= vga_postswitch,
115 	.vd_priority	= VD_PRIORITY_GENERIC,
116 };
117 
118 /*
119  * Driver supports both text mode and graphics mode.  Make sure the
120  * buffer is always big enough to support both.
121  */
122 static struct vga_softc vga_conssoftc;
123 VT_DRIVER_DECLARE(vt_vga, vt_vga_driver);
124 
125 static inline void
126 vga_setwmode(struct vt_device *vd, int wmode)
127 {
128 	struct vga_softc *sc = vd->vd_softc;
129 
130 	if (sc->vga_wmode == wmode)
131 		return;
132 
133 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_MODE);
134 	REG_WRITE1(sc, VGA_GC_DATA, wmode);
135 	sc->vga_wmode = wmode;
136 
137 	switch (wmode) {
138 	case 3:
139 		/* Re-enable all planes. */
140 		REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_MAP_MASK);
141 		REG_WRITE1(sc, VGA_SEQ_DATA, VGA_SEQ_MM_EM3 | VGA_SEQ_MM_EM2 |
142 		    VGA_SEQ_MM_EM1 | VGA_SEQ_MM_EM0);
143 		break;
144 	}
145 }
146 
147 static inline void
148 vga_setfg(struct vt_device *vd, term_color_t color)
149 {
150 	struct vga_softc *sc = vd->vd_softc;
151 
152 	vga_setwmode(vd, 3);
153 
154 	if (sc->vga_curfg == color)
155 		return;
156 
157 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_SET_RESET);
158 	REG_WRITE1(sc, VGA_GC_DATA, cons_to_vga_colors[color]);
159 	sc->vga_curfg = color;
160 }
161 
162 static inline void
163 vga_setbg(struct vt_device *vd, term_color_t color)
164 {
165 	struct vga_softc *sc = vd->vd_softc;
166 
167 	vga_setwmode(vd, 3);
168 
169 	if (sc->vga_curbg == color)
170 		return;
171 
172 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_SET_RESET);
173 	REG_WRITE1(sc, VGA_GC_DATA, cons_to_vga_colors[color]);
174 
175 	/*
176 	 * Write 8 pixels using the background color to an off-screen
177 	 * byte in the video memory.
178 	 */
179 	MEM_WRITE1(sc, VT_VGA_BGCOLOR_OFFSET, 0xff);
180 
181 	/*
182 	 * Read those 8 pixels back to load the background color in the
183 	 * latches register.
184 	 */
185 	MEM_READ1(sc, VT_VGA_BGCOLOR_OFFSET);
186 
187 	sc->vga_curbg = color;
188 
189 	/*
190          * The Set/Reset register doesn't contain the fg color anymore,
191          * store an invalid color.
192 	 */
193 	sc->vga_curfg = 0xff;
194 }
195 
196 /*
197  * Binary searchable table for Unicode to CP437 conversion.
198  */
199 
200 struct unicp437 {
201 	uint16_t	unicode_base;
202 	uint8_t		cp437_base;
203 	uint8_t		length;
204 };
205 
206 static const struct unicp437 cp437table[] = {
207 	{ 0x0020, 0x20, 0x5e }, { 0x00a0, 0x20, 0x00 },
208 	{ 0x00a1, 0xad, 0x00 }, { 0x00a2, 0x9b, 0x00 },
209 	{ 0x00a3, 0x9c, 0x00 }, { 0x00a5, 0x9d, 0x00 },
210 	{ 0x00a6, 0x7c, 0x00 },
211 	{ 0x00a7, 0x15, 0x00 }, { 0x00aa, 0xa6, 0x00 },
212 	{ 0x00ab, 0xae, 0x00 }, { 0x00ac, 0xaa, 0x00 },
213 	{ 0x00b0, 0xf8, 0x00 }, { 0x00b1, 0xf1, 0x00 },
214 	{ 0x00b2, 0xfd, 0x00 }, { 0x00b5, 0xe6, 0x00 },
215 	{ 0x00b6, 0x14, 0x00 }, { 0x00b7, 0xfa, 0x00 },
216 	{ 0x00ba, 0xa7, 0x00 }, { 0x00bb, 0xaf, 0x00 },
217 	{ 0x00bc, 0xac, 0x00 }, { 0x00bd, 0xab, 0x00 },
218 	{ 0x00bf, 0xa8, 0x00 }, { 0x00c4, 0x8e, 0x01 },
219 	{ 0x00c6, 0x92, 0x00 }, { 0x00c7, 0x80, 0x00 },
220 	{ 0x00c9, 0x90, 0x00 }, { 0x00d1, 0xa5, 0x00 },
221 	{ 0x00d6, 0x99, 0x00 }, { 0x00dc, 0x9a, 0x00 },
222 	{ 0x00df, 0xe1, 0x00 }, { 0x00e0, 0x85, 0x00 },
223 	{ 0x00e1, 0xa0, 0x00 }, { 0x00e2, 0x83, 0x00 },
224 	{ 0x00e4, 0x84, 0x00 }, { 0x00e5, 0x86, 0x00 },
225 	{ 0x00e6, 0x91, 0x00 }, { 0x00e7, 0x87, 0x00 },
226 	{ 0x00e8, 0x8a, 0x00 }, { 0x00e9, 0x82, 0x00 },
227 	{ 0x00ea, 0x88, 0x01 }, { 0x00ec, 0x8d, 0x00 },
228 	{ 0x00ed, 0xa1, 0x00 }, { 0x00ee, 0x8c, 0x00 },
229 	{ 0x00ef, 0x8b, 0x00 }, { 0x00f0, 0xeb, 0x00 },
230 	{ 0x00f1, 0xa4, 0x00 }, { 0x00f2, 0x95, 0x00 },
231 	{ 0x00f3, 0xa2, 0x00 }, { 0x00f4, 0x93, 0x00 },
232 	{ 0x00f6, 0x94, 0x00 }, { 0x00f7, 0xf6, 0x00 },
233 	{ 0x00f8, 0xed, 0x00 }, { 0x00f9, 0x97, 0x00 },
234 	{ 0x00fa, 0xa3, 0x00 }, { 0x00fb, 0x96, 0x00 },
235 	{ 0x00fc, 0x81, 0x00 }, { 0x00ff, 0x98, 0x00 },
236 	{ 0x0192, 0x9f, 0x00 }, { 0x0393, 0xe2, 0x00 },
237 	{ 0x0398, 0xe9, 0x00 }, { 0x03a3, 0xe4, 0x00 },
238 	{ 0x03a6, 0xe8, 0x00 }, { 0x03a9, 0xea, 0x00 },
239 	{ 0x03b1, 0xe0, 0x01 }, { 0x03b4, 0xeb, 0x00 },
240 	{ 0x03b5, 0xee, 0x00 }, { 0x03bc, 0xe6, 0x00 },
241 	{ 0x03c0, 0xe3, 0x00 }, { 0x03c3, 0xe5, 0x00 },
242 	{ 0x03c4, 0xe7, 0x00 }, { 0x03c6, 0xed, 0x00 },
243 	{ 0x03d5, 0xed, 0x00 }, { 0x2010, 0x2d, 0x00 },
244 	{ 0x2013, 0x2d, 0x00 },
245 	{ 0x2014, 0x2d, 0x00 }, { 0x2018, 0x60, 0x00 },
246 	{ 0x2019, 0x27, 0x00 }, { 0x201c, 0x22, 0x00 },
247 	{ 0x201d, 0x22, 0x00 }, { 0x2022, 0x07, 0x00 },
248 	{ 0x203c, 0x13, 0x00 }, { 0x207f, 0xfc, 0x00 },
249 	{ 0x20a7, 0x9e, 0x00 }, { 0x20ac, 0xee, 0x00 },
250 	{ 0x2126, 0xea, 0x00 }, { 0x2190, 0x1b, 0x00 },
251 	{ 0x2191, 0x18, 0x00 }, { 0x2192, 0x1a, 0x00 },
252 	{ 0x2193, 0x19, 0x00 }, { 0x2194, 0x1d, 0x00 },
253 	{ 0x2195, 0x12, 0x00 }, { 0x21a8, 0x17, 0x00 },
254 	{ 0x2202, 0xeb, 0x00 }, { 0x2208, 0xee, 0x00 },
255 	{ 0x2211, 0xe4, 0x00 }, { 0x2212, 0x2d, 0x00 },
256 	{ 0x2219, 0xf9, 0x00 }, { 0x221a, 0xfb, 0x00 },
257 	{ 0x221e, 0xec, 0x00 }, { 0x221f, 0x1c, 0x00 },
258 	{ 0x2229, 0xef, 0x00 }, { 0x2248, 0xf7, 0x00 },
259 	{ 0x2261, 0xf0, 0x00 }, { 0x2264, 0xf3, 0x00 },
260 	{ 0x2265, 0xf2, 0x00 }, { 0x2302, 0x7f, 0x00 },
261 	{ 0x2310, 0xa9, 0x00 }, { 0x2320, 0xf4, 0x00 },
262 	{ 0x2321, 0xf5, 0x00 }, { 0x2500, 0xc4, 0x00 },
263 	{ 0x2502, 0xb3, 0x00 }, { 0x250c, 0xda, 0x00 },
264 	{ 0x2510, 0xbf, 0x00 }, { 0x2514, 0xc0, 0x00 },
265 	{ 0x2518, 0xd9, 0x00 }, { 0x251c, 0xc3, 0x00 },
266 	{ 0x2524, 0xb4, 0x00 }, { 0x252c, 0xc2, 0x00 },
267 	{ 0x2534, 0xc1, 0x00 }, { 0x253c, 0xc5, 0x00 },
268 	{ 0x2550, 0xcd, 0x00 }, { 0x2551, 0xba, 0x00 },
269 	{ 0x2552, 0xd5, 0x00 }, { 0x2553, 0xd6, 0x00 },
270 	{ 0x2554, 0xc9, 0x00 }, { 0x2555, 0xb8, 0x00 },
271 	{ 0x2556, 0xb7, 0x00 }, { 0x2557, 0xbb, 0x00 },
272 	{ 0x2558, 0xd4, 0x00 }, { 0x2559, 0xd3, 0x00 },
273 	{ 0x255a, 0xc8, 0x00 }, { 0x255b, 0xbe, 0x00 },
274 	{ 0x255c, 0xbd, 0x00 }, { 0x255d, 0xbc, 0x00 },
275 	{ 0x255e, 0xc6, 0x01 }, { 0x2560, 0xcc, 0x00 },
276 	{ 0x2561, 0xb5, 0x00 }, { 0x2562, 0xb6, 0x00 },
277 	{ 0x2563, 0xb9, 0x00 }, { 0x2564, 0xd1, 0x01 },
278 	{ 0x2566, 0xcb, 0x00 }, { 0x2567, 0xcf, 0x00 },
279 	{ 0x2568, 0xd0, 0x00 }, { 0x2569, 0xca, 0x00 },
280 	{ 0x256a, 0xd8, 0x00 }, { 0x256b, 0xd7, 0x00 },
281 	{ 0x256c, 0xce, 0x00 }, { 0x2580, 0xdf, 0x00 },
282 	{ 0x2584, 0xdc, 0x00 }, { 0x2588, 0xdb, 0x00 },
283 	{ 0x258c, 0xdd, 0x00 }, { 0x2590, 0xde, 0x00 },
284 	{ 0x2591, 0xb0, 0x02 }, { 0x25a0, 0xfe, 0x00 },
285 	{ 0x25ac, 0x16, 0x00 }, { 0x25b2, 0x1e, 0x00 },
286 	{ 0x25ba, 0x10, 0x00 }, { 0x25bc, 0x1f, 0x00 },
287 	{ 0x25c4, 0x11, 0x00 }, { 0x25cb, 0x09, 0x00 },
288 	{ 0x25d8, 0x08, 0x00 }, { 0x25d9, 0x0a, 0x00 },
289 	{ 0x263a, 0x01, 0x01 }, { 0x263c, 0x0f, 0x00 },
290 	{ 0x2640, 0x0c, 0x00 }, { 0x2642, 0x0b, 0x00 },
291 	{ 0x2660, 0x06, 0x00 }, { 0x2663, 0x05, 0x00 },
292 	{ 0x2665, 0x03, 0x01 }, { 0x266a, 0x0d, 0x00 },
293 	{ 0x266c, 0x0e, 0x00 }, { 0x2713, 0xfb, 0x00 },
294 	{ 0x27e8, 0x3c, 0x00 }, { 0x27e9, 0x3e, 0x00 },
295 };
296 
297 static uint8_t
298 vga_get_cp437(term_char_t c)
299 {
300 	int min, mid, max;
301 
302 	min = 0;
303 	max = nitems(cp437table) - 1;
304 
305 	if (c < cp437table[0].unicode_base ||
306 	    c > cp437table[max].unicode_base + cp437table[max].length)
307 		return '?';
308 
309 	while (max >= min) {
310 		mid = (min + max) / 2;
311 		if (c < cp437table[mid].unicode_base)
312 			max = mid - 1;
313 		else if (c > cp437table[mid].unicode_base +
314 		    cp437table[mid].length)
315 			min = mid + 1;
316 		else
317 			return (c - cp437table[mid].unicode_base +
318 			    cp437table[mid].cp437_base);
319 	}
320 
321 	return '?';
322 }
323 
324 static void
325 vga_blank(struct vt_device *vd, term_color_t color)
326 {
327 	struct vga_softc *sc = vd->vd_softc;
328 	u_int ofs;
329 
330 	vga_setfg(vd, color);
331 	for (ofs = 0; ofs < VT_VGA_MEMSIZE; ofs++)
332 		MEM_WRITE1(sc, ofs, 0xff);
333 }
334 
335 static inline void
336 vga_bitblt_put(struct vt_device *vd, u_long dst, term_color_t color,
337     uint8_t v)
338 {
339 	struct vga_softc *sc = vd->vd_softc;
340 
341 	/* Skip empty writes, in order to avoid palette changes. */
342 	if (v != 0x00) {
343 		vga_setfg(vd, color);
344 		/*
345 		 * When this MEM_READ1() gets disabled, all sorts of
346 		 * artifacts occur.  This is because this read loads the
347 		 * set of 8 pixels that are about to be changed.  There
348 		 * is one scenario where we can avoid the read, namely
349 		 * if all pixels are about to be overwritten anyway.
350 		 */
351 		if (v != 0xff) {
352 			MEM_READ1(sc, dst);
353 
354 			/* The bg color was trashed by the reads. */
355 			sc->vga_curbg = 0xff;
356 		}
357 		MEM_WRITE1(sc, dst, v);
358 	}
359 }
360 
361 static void
362 vga_setpixel(struct vt_device *vd, int x, int y, term_color_t color)
363 {
364 
365 	if (vd->vd_flags & VDF_TEXTMODE)
366 		return;
367 
368 	vga_bitblt_put(vd, (y * VT_VGA_WIDTH / 8) + (x / 8), color,
369 	    0x80 >> (x % 8));
370 }
371 
372 static void
373 vga_drawrect(struct vt_device *vd, int x1, int y1, int x2, int y2, int fill,
374     term_color_t color)
375 {
376 	int x, y;
377 
378 	if (vd->vd_flags & VDF_TEXTMODE)
379 		return;
380 
381 	for (y = y1; y <= y2; y++) {
382 		if (fill || (y == y1) || (y == y2)) {
383 			for (x = x1; x <= x2; x++)
384 				vga_setpixel(vd, x, y, color);
385 		} else {
386 			vga_setpixel(vd, x1, y, color);
387 			vga_setpixel(vd, x2, y, color);
388 		}
389 	}
390 }
391 
392 static void
393 vga_compute_shifted_pattern(const uint8_t *src, unsigned int bytes,
394     unsigned int src_x, unsigned int x_count, unsigned int dst_x,
395     uint8_t *pattern, uint8_t *mask)
396 {
397 	unsigned int n;
398 
399 	n = src_x / 8;
400 
401 	/*
402 	 * This mask has bits set, where a pixel (ether 0 or 1)
403 	 * comes from the source bitmap.
404 	 */
405 	if (mask != NULL) {
406 		*mask = (0xff
407 		    >> (8 - x_count))
408 		    << (8 - x_count - dst_x);
409 	}
410 
411 	if (n == (src_x + x_count - 1) / 8) {
412 		/* All the pixels we want are in the same byte. */
413 		*pattern = src[n];
414 		if (dst_x >= src_x)
415 			*pattern >>= (dst_x - src_x % 8);
416 		else
417 			*pattern <<= (src_x % 8 - dst_x);
418 	} else {
419 		/* The pixels we want are split into two bytes. */
420 		if (dst_x >= src_x % 8) {
421 			*pattern =
422 			    src[n] << (8 - dst_x - src_x % 8) |
423 			    src[n + 1] >> (dst_x - src_x % 8);
424 		} else {
425 			*pattern =
426 			    src[n] << (src_x % 8 - dst_x) |
427 			    src[n + 1] >> (8 - src_x % 8 - dst_x);
428 		}
429 	}
430 }
431 
432 static void
433 vga_copy_bitmap_portion(uint8_t *pattern_2colors, uint8_t *pattern_ncolors,
434     const uint8_t *src, const uint8_t *src_mask, unsigned int src_width,
435     unsigned int src_x, unsigned int dst_x, unsigned int x_count,
436     unsigned int src_y, unsigned int dst_y, unsigned int y_count,
437     term_color_t fg, term_color_t bg, int overwrite)
438 {
439 	unsigned int i, bytes;
440 	uint8_t pattern, relevant_bits, mask;
441 
442 	bytes = (src_width + 7) / 8;
443 
444 	for (i = 0; i < y_count; ++i) {
445 		vga_compute_shifted_pattern(src + (src_y + i) * bytes,
446 		    bytes, src_x, x_count, dst_x, &pattern, &relevant_bits);
447 
448 		if (src_mask == NULL) {
449 			/*
450 			 * No src mask. Consider that all wanted bits
451 			 * from the source are "authoritative".
452 			 */
453 			mask = relevant_bits;
454 		} else {
455 			/*
456 			 * There's an src mask. We shift it the same way
457 			 * we shifted the source pattern.
458 			 */
459 			vga_compute_shifted_pattern(
460 			    src_mask + (src_y + i) * bytes,
461 			    bytes, src_x, x_count, dst_x,
462 			    &mask, NULL);
463 
464 			/* Now, only keep the wanted bits among them. */
465 			mask &= relevant_bits;
466 		}
467 
468 		/*
469 		 * Clear bits from the pattern which must be
470 		 * transparent, according to the source mask.
471 		 */
472 		pattern &= mask;
473 
474 		/* Set the bits in the 2-colors array. */
475 		if (overwrite)
476 			pattern_2colors[dst_y + i] &= ~mask;
477 		pattern_2colors[dst_y + i] |= pattern;
478 
479 		if (pattern_ncolors == NULL)
480 			continue;
481 
482 		/*
483 		 * Set the same bits in the n-colors array. This one
484 		 * supports transparency, when a given bit is cleared in
485 		 * all colors.
486 		 */
487 		if (overwrite) {
488 			/*
489 			 * Ensure that the pixels used by this bitmap are
490 			 * cleared in other colors.
491 			 */
492 			for (int j = 0; j < 16; ++j)
493 				pattern_ncolors[(dst_y + i) * 16 + j] &=
494 				    ~mask;
495 		}
496 		pattern_ncolors[(dst_y + i) * 16 + fg] |= pattern;
497 		pattern_ncolors[(dst_y + i) * 16 + bg] |= (~pattern & mask);
498 	}
499 }
500 
501 static void
502 vga_bitblt_pixels_block_2colors(struct vt_device *vd, const uint8_t *masks,
503     term_color_t fg, term_color_t bg,
504     unsigned int x, unsigned int y, unsigned int height)
505 {
506 	unsigned int i, offset;
507 	struct vga_softc *sc;
508 
509 	/*
510 	 * The great advantage of Write Mode 3 is that we just need
511 	 * to load the foreground in the Set/Reset register, load the
512 	 * background color in the latches register (this is done
513 	 * through a write in offscreen memory followed by a read of
514 	 * that data), then write the pattern to video memory. This
515 	 * pattern indicates if the pixel should use the foreground
516 	 * color (bit set) or the background color (bit cleared).
517 	 */
518 
519 	vga_setbg(vd, bg);
520 	vga_setfg(vd, fg);
521 
522 	sc = vd->vd_softc;
523 	offset = (VT_VGA_WIDTH * y + x) / 8;
524 
525 	for (i = 0; i < height; ++i, offset += VT_VGA_WIDTH / 8) {
526 		MEM_WRITE1(sc, offset, masks[i]);
527 	}
528 }
529 
530 static void
531 vga_bitblt_pixels_block_ncolors(struct vt_device *vd, const uint8_t *masks,
532     unsigned int x, unsigned int y, unsigned int height)
533 {
534 	unsigned int i, j, plane, color, offset;
535 	struct vga_softc *sc;
536 	uint8_t mask, planes[height * 4];
537 
538 	sc = vd->vd_softc;
539 
540 	memset(planes, 0, sizeof(planes));
541 
542 	/*
543          * To write a group of pixels using 3 or more colors, we select
544          * Write Mode 0 and write one byte to each plane separately.
545 	 */
546 
547 	/*
548 	 * We first compute each byte: each plane contains one bit of the
549 	 * color code for each of the 8 pixels.
550 	 *
551 	 * For example, if the 8 pixels are like this:
552 	 *     GBBBBBBY
553 	 * where:
554 	 *     G (gray)   = 0b0111
555 	 *     B (black)  = 0b0000
556 	 *     Y (yellow) = 0b0011
557 	 *
558 	 * The corresponding for bytes are:
559 	 *             GBBBBBBY
560 	 *    Plane 0: 10000001 = 0x81
561 	 *    Plane 1: 10000001 = 0x81
562 	 *    Plane 2: 10000000 = 0x80
563 	 *    Plane 3: 00000000 = 0x00
564 	 *             |  |   |
565 	 *             |  |   +-> 0b0011 (Y)
566 	 *             |  +-----> 0b0000 (B)
567 	 *             +--------> 0b0111 (G)
568 	 */
569 
570 	for (i = 0; i < height; ++i) {
571 		for (color = 0; color < 16; ++color) {
572 			mask = masks[i * 16 + color];
573 			if (mask == 0x00)
574 				continue;
575 
576 			for (j = 0; j < 8; ++j) {
577 				if (!((mask >> (7 - j)) & 0x1))
578 					continue;
579 
580 				/* The pixel "j" uses color "color". */
581 				for (plane = 0; plane < 4; ++plane)
582 					planes[i * 4 + plane] |=
583 					    ((cons_to_vga_colors[color] >>
584 					    plane) & 0x1) << (7 - j);
585 			}
586 		}
587 	}
588 
589 	/*
590 	 * The bytes are ready: we now switch to Write Mode 0 and write
591 	 * all bytes, one plane at a time.
592 	 */
593 	vga_setwmode(vd, 0);
594 
595 	REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_MAP_MASK);
596 	for (plane = 0; plane < 4; ++plane) {
597 		/* Select plane. */
598 		REG_WRITE1(sc, VGA_SEQ_DATA, 1 << plane);
599 
600 		/* Write all bytes for this plane, from Y to Y+height. */
601 		for (i = 0; i < height; ++i) {
602 			offset = (VT_VGA_WIDTH * (y + i) + x) / 8;
603 			MEM_WRITE1(sc, offset, planes[i * 4 + plane]);
604 		}
605 	}
606 }
607 
608 static void
609 vga_bitblt_one_text_pixels_block(struct vt_device *vd,
610     const struct vt_window *vw, unsigned int x, unsigned int y)
611 {
612 	const struct vt_buf *vb;
613 	const struct vt_font *vf;
614 	unsigned int i, col, row, src_x, x_count;
615 	unsigned int used_colors_list[16], used_colors;
616 	uint8_t pattern_2colors[vw->vw_font->vf_height];
617 	uint8_t pattern_ncolors[vw->vw_font->vf_height * 16];
618 	term_char_t c;
619 	term_color_t fg, bg;
620 	const uint8_t *src;
621 
622 	vb = &vw->vw_buf;
623 	vf = vw->vw_font;
624 
625 	/*
626 	 * The current pixels block.
627 	 *
628 	 * We fill it with portions of characters, because both "grids"
629 	 * may not match.
630 	 *
631 	 * i is the index in this pixels block.
632 	 */
633 
634 	i = x;
635 	used_colors = 0;
636 	memset(used_colors_list, 0, sizeof(used_colors_list));
637 	memset(pattern_2colors, 0, sizeof(pattern_2colors));
638 	memset(pattern_ncolors, 0, sizeof(pattern_ncolors));
639 
640 	if (i < vw->vw_draw_area.tr_begin.tp_col) {
641 		/*
642 		 * i is in the margin used to center the text area on
643 		 * the screen.
644 		 */
645 
646 		i = vw->vw_draw_area.tr_begin.tp_col;
647 	}
648 
649 	while (i < x + VT_VGA_PIXELS_BLOCK &&
650 	    i < vw->vw_draw_area.tr_end.tp_col) {
651 		/*
652 		 * Find which character is drawn on this pixel in the
653 		 * pixels block.
654 		 *
655 		 * While here, record what colors it uses.
656 		 */
657 
658 		col = (i - vw->vw_draw_area.tr_begin.tp_col) / vf->vf_width;
659 		row = (y - vw->vw_draw_area.tr_begin.tp_row) / vf->vf_height;
660 
661 		c = VTBUF_GET_FIELD(vb, row, col);
662 		src = vtfont_lookup(vf, c);
663 
664 		vt_determine_colors(c, VTBUF_ISCURSOR(vb, row, col), &fg, &bg);
665 		if ((used_colors_list[fg] & 0x1) != 0x1)
666 			used_colors++;
667 		if ((used_colors_list[bg] & 0x2) != 0x2)
668 			used_colors++;
669 		used_colors_list[fg] |= 0x1;
670 		used_colors_list[bg] |= 0x2;
671 
672 		/*
673 		 * Compute the portion of the character we want to draw,
674 		 * because the pixels block may start in the middle of a
675 		 * character.
676 		 *
677 		 * The first pixel to draw in the character is
678 		 *     the current position -
679 		 *     the start position of the character
680 		 *
681 		 * The last pixel to draw is either
682 		 *     - the last pixel of the character, or
683 		 *     - the pixel of the character matching the end of
684 		 *       the pixels block
685 		 * whichever comes first. This position is then
686 		 * changed to be relative to the start position of the
687 		 * character.
688 		 */
689 
690 		src_x = i -
691 		    (col * vf->vf_width + vw->vw_draw_area.tr_begin.tp_col);
692 		x_count = min(min(
693 		    (col + 1) * vf->vf_width +
694 		    vw->vw_draw_area.tr_begin.tp_col,
695 		    x + VT_VGA_PIXELS_BLOCK),
696 		    vw->vw_draw_area.tr_end.tp_col);
697 		x_count -= col * vf->vf_width +
698 		    vw->vw_draw_area.tr_begin.tp_col;
699 		x_count -= src_x;
700 
701 		/* Copy a portion of the character. */
702 		vga_copy_bitmap_portion(pattern_2colors, pattern_ncolors,
703 		    src, NULL, vf->vf_width,
704 		    src_x, i % VT_VGA_PIXELS_BLOCK, x_count,
705 		    0, 0, vf->vf_height, fg, bg, 0);
706 
707 		/* We move to the next portion. */
708 		i += x_count;
709 	}
710 
711 #ifndef SC_NO_CUTPASTE
712 	/*
713 	 * Copy the mouse pointer bitmap if it's over the current pixels
714 	 * block.
715 	 *
716 	 * We use the saved cursor position (saved in vt_flush()), because
717 	 * the current position could be different than the one used
718 	 * to mark the area dirty.
719 	 */
720 	term_rect_t drawn_area;
721 
722 	drawn_area.tr_begin.tp_col = x;
723 	drawn_area.tr_begin.tp_row = y;
724 	drawn_area.tr_end.tp_col = x + VT_VGA_PIXELS_BLOCK;
725 	drawn_area.tr_end.tp_row = y + vf->vf_height;
726 	if (vd->vd_mshown && vt_is_cursor_in_area(vd, &drawn_area)) {
727 		struct vt_mouse_cursor *cursor;
728 		unsigned int mx, my;
729 		unsigned int dst_x, src_y, dst_y, y_count;
730 
731 		cursor = vd->vd_mcursor;
732 		mx = vd->vd_mx_drawn + vw->vw_draw_area.tr_begin.tp_col;
733 		my = vd->vd_my_drawn + vw->vw_draw_area.tr_begin.tp_row;
734 
735 		/* Compute the portion of the cursor we want to copy. */
736 		src_x = x > mx ? x - mx : 0;
737 		dst_x = mx > x ? mx - x : 0;
738 		x_count = min(min(min(
739 		    cursor->width - src_x,
740 		    x + VT_VGA_PIXELS_BLOCK - mx),
741 		    vw->vw_draw_area.tr_end.tp_col - mx),
742 		    VT_VGA_PIXELS_BLOCK);
743 
744 		/*
745 		 * The cursor isn't aligned on the Y-axis with
746 		 * characters, so we need to compute the vertical
747 		 * start/count.
748 		 */
749 		src_y = y > my ? y - my : 0;
750 		dst_y = my > y ? my - y : 0;
751 		y_count = min(
752 		    min(cursor->height - src_y, y + vf->vf_height - my),
753 		    vf->vf_height);
754 
755 		/* Copy the cursor portion. */
756 		vga_copy_bitmap_portion(pattern_2colors, pattern_ncolors,
757 		    cursor->map, cursor->mask, cursor->width,
758 		    src_x, dst_x, x_count, src_y, dst_y, y_count,
759 		    vd->vd_mcursor_fg, vd->vd_mcursor_bg, 1);
760 
761 		if ((used_colors_list[vd->vd_mcursor_fg] & 0x1) != 0x1)
762 			used_colors++;
763 		if ((used_colors_list[vd->vd_mcursor_bg] & 0x2) != 0x2)
764 			used_colors++;
765 	}
766 #endif
767 
768 	/*
769 	 * The pixels block is completed, we can now draw it on the
770 	 * screen.
771 	 */
772 	if (used_colors == 2)
773 		vga_bitblt_pixels_block_2colors(vd, pattern_2colors, fg, bg,
774 		    x, y, vf->vf_height);
775 	else
776 		vga_bitblt_pixels_block_ncolors(vd, pattern_ncolors,
777 		    x, y, vf->vf_height);
778 }
779 
780 static void
781 vga_bitblt_text_gfxmode(struct vt_device *vd, const struct vt_window *vw,
782     const term_rect_t *area)
783 {
784 	const struct vt_font *vf;
785 	unsigned int col, row;
786 	unsigned int x1, y1, x2, y2, x, y;
787 
788 	vf = vw->vw_font;
789 
790 	/*
791 	 * Compute the top-left pixel position aligned with the video
792 	 * adapter pixels block size.
793 	 *
794 	 * This is calculated from the top-left column of te dirty area:
795 	 *
796 	 *     1. Compute the top-left pixel of the character:
797 	 *        col * font width + x offset
798 	 *
799 	 *        NOTE: x offset is used to center the text area on the
800 	 *        screen. It's expressed in pixels, not in characters
801 	 *        col/row!
802 	 *
803 	 *     2. Find the pixel further on the left marking the start of
804 	 *        an aligned pixels block (eg. chunk of 8 pixels):
805 	 *        character's x / blocksize * blocksize
806 	 *
807 	 *        The division, being made on integers, achieves the
808 	 *        alignment.
809 	 *
810 	 * For the Y-axis, we need to compute the character's y
811 	 * coordinate, but we don't need to align it.
812 	 */
813 
814 	col = area->tr_begin.tp_col;
815 	row = area->tr_begin.tp_row;
816 	x1 = (int)((col * vf->vf_width + vw->vw_draw_area.tr_begin.tp_col)
817 	     / VT_VGA_PIXELS_BLOCK)
818 	    * VT_VGA_PIXELS_BLOCK;
819 	y1 = row * vf->vf_height + vw->vw_draw_area.tr_begin.tp_row;
820 
821 	/*
822 	 * Compute the bottom right pixel position, again, aligned with
823 	 * the pixels block size.
824 	 *
825 	 * The same rules apply, we just add 1 to base the computation
826 	 * on the "right border" of the dirty area.
827 	 */
828 
829 	col = area->tr_end.tp_col;
830 	row = area->tr_end.tp_row;
831 	x2 = (int)howmany(col * vf->vf_width + vw->vw_draw_area.tr_begin.tp_col,
832 	    VT_VGA_PIXELS_BLOCK)
833 	    * VT_VGA_PIXELS_BLOCK;
834 	y2 = row * vf->vf_height + vw->vw_draw_area.tr_begin.tp_row;
835 
836 	/* Clip the area to the screen size. */
837 	x2 = min(x2, vw->vw_draw_area.tr_end.tp_col);
838 	y2 = min(y2, vw->vw_draw_area.tr_end.tp_row);
839 
840 	/*
841 	 * Now, we take care of N pixels line at a time (the first for
842 	 * loop, N = font height), and for these lines, draw one pixels
843 	 * block at a time (the second for loop), not a character at a
844 	 * time.
845 	 *
846 	 * Therefore, on the X-axis, characters my be drawn partially if
847 	 * they are not aligned on 8-pixels boundary.
848 	 *
849 	 * However, the operation is repeated for the full height of the
850 	 * font before moving to the next character, because it allows
851 	 * to keep the color settings and write mode, before perhaps
852 	 * changing them with the next one.
853 	 */
854 
855 	for (y = y1; y < y2; y += vf->vf_height) {
856 		for (x = x1; x < x2; x += VT_VGA_PIXELS_BLOCK) {
857 			vga_bitblt_one_text_pixels_block(vd, vw, x, y);
858 		}
859 	}
860 }
861 
862 static void
863 vga_bitblt_text_txtmode(struct vt_device *vd, const struct vt_window *vw,
864     const term_rect_t *area)
865 {
866 	struct vga_softc *sc;
867 	const struct vt_buf *vb;
868 	unsigned int col, row;
869 	term_char_t c;
870 	term_color_t fg, bg;
871 	uint8_t ch, attr;
872 	size_t z;
873 
874 	sc = vd->vd_softc;
875 	vb = &vw->vw_buf;
876 
877 	for (row = area->tr_begin.tp_row; row < area->tr_end.tp_row; ++row) {
878 		for (col = area->tr_begin.tp_col;
879 		    col < area->tr_end.tp_col;
880 		    ++col) {
881 			/*
882 			 * Get next character and its associated fg/bg
883 			 * colors.
884 			 */
885 			c = VTBUF_GET_FIELD(vb, row, col);
886 			vt_determine_colors(c, VTBUF_ISCURSOR(vb, row, col),
887 			    &fg, &bg);
888 
889 			z = row * PIXEL_WIDTH(VT_FB_MAX_WIDTH) + col;
890 			if (z >= PIXEL_HEIGHT(VT_FB_MAX_HEIGHT) *
891 			    PIXEL_WIDTH(VT_FB_MAX_WIDTH))
892 				continue;
893 			if (vd->vd_drawn && (vd->vd_drawn[z] == c) &&
894 			    vd->vd_drawnfg && (vd->vd_drawnfg[z] == fg) &&
895 			    vd->vd_drawnbg && (vd->vd_drawnbg[z] == bg))
896 				continue;
897 
898 			/*
899 			 * Convert character to CP437, which is the
900 			 * character set used by the VGA hardware by
901 			 * default.
902 			 */
903 			ch = vga_get_cp437(TCHAR_CHARACTER(c));
904 
905 			/* Convert colors to VGA attributes. */
906 			attr =
907 			    cons_to_vga_colors[bg] << 4 |
908 			    cons_to_vga_colors[fg];
909 
910 			MEM_WRITE2(sc, (row * 80 + col) * 2 + 0,
911 			    ch + ((uint16_t)(attr) << 8));
912 
913 			if (vd->vd_drawn)
914 				vd->vd_drawn[z] = c;
915 			if (vd->vd_drawnfg)
916 				vd->vd_drawnfg[z] = fg;
917 			if (vd->vd_drawnbg)
918 				vd->vd_drawnbg[z] = bg;
919 		}
920 	}
921 }
922 
923 static void
924 vga_bitblt_text(struct vt_device *vd, const struct vt_window *vw,
925     const term_rect_t *area)
926 {
927 
928 	if (!(vd->vd_flags & VDF_TEXTMODE)) {
929 		vga_bitblt_text_gfxmode(vd, vw, area);
930 	} else {
931 		vga_bitblt_text_txtmode(vd, vw, area);
932 	}
933 }
934 
935 void
936 vga_invalidate_text(struct vt_device *vd, const term_rect_t *area)
937 {
938 	unsigned int col, row;
939 	size_t z;
940 
941 	for (row = area->tr_begin.tp_row; row < area->tr_end.tp_row; ++row) {
942 		for (col = area->tr_begin.tp_col;
943 		    col < area->tr_end.tp_col;
944 		    ++col) {
945 			z = row * PIXEL_WIDTH(VT_FB_MAX_WIDTH) + col;
946 			if (z >= PIXEL_HEIGHT(VT_FB_MAX_HEIGHT) *
947 			    PIXEL_WIDTH(VT_FB_MAX_WIDTH))
948 				continue;
949 			if (vd->vd_drawn)
950 				vd->vd_drawn[z] = 0;
951 			if (vd->vd_drawnfg)
952 				vd->vd_drawnfg[z] = 0;
953 			if (vd->vd_drawnbg)
954 				vd->vd_drawnbg[z] = 0;
955 		}
956 	}
957 }
958 
959 static void
960 vga_bitblt_bitmap(struct vt_device *vd, const struct vt_window *vw,
961     const uint8_t *pattern, const uint8_t *mask,
962     unsigned int width, unsigned int height,
963     unsigned int x, unsigned int y, term_color_t fg, term_color_t bg)
964 {
965 	unsigned int x1, y1, x2, y2, i, j, src_x, dst_x, x_count;
966 	uint8_t pattern_2colors;
967 
968 	/* Align coordinates with the 8-pxels grid. */
969 	x1 = rounddown(x, VT_VGA_PIXELS_BLOCK);
970 	y1 = y;
971 
972 	x2 = roundup(x + width, VT_VGA_PIXELS_BLOCK);
973 	y2 = y + height;
974 	x2 = min(x2, vd->vd_width - 1);
975 	y2 = min(y2, vd->vd_height - 1);
976 
977 	for (j = y1; j < y2; ++j) {
978 		src_x = 0;
979 		dst_x = x - x1;
980 		x_count = VT_VGA_PIXELS_BLOCK - dst_x;
981 
982 		for (i = x1; i < x2; i += VT_VGA_PIXELS_BLOCK) {
983 			pattern_2colors = 0;
984 
985 			vga_copy_bitmap_portion(
986 			    &pattern_2colors, NULL,
987 			    pattern, mask, width,
988 			    src_x, dst_x, x_count,
989 			    j - y1, 0, 1, fg, bg, 0);
990 
991 			vga_bitblt_pixels_block_2colors(vd,
992 			    &pattern_2colors, fg, bg,
993 			    i, j, 1);
994 
995 			src_x += x_count;
996 			dst_x = (dst_x + x_count) % VT_VGA_PIXELS_BLOCK;
997 			x_count = min(width - src_x, VT_VGA_PIXELS_BLOCK);
998 		}
999 	}
1000 }
1001 
1002 static void
1003 vga_initialize_graphics(struct vt_device *vd)
1004 {
1005 	struct vga_softc *sc = vd->vd_softc;
1006 
1007 	/* Clock select. */
1008 	REG_WRITE1(sc, VGA_GEN_MISC_OUTPUT_W, VGA_GEN_MO_VSP | VGA_GEN_MO_HSP |
1009 	    VGA_GEN_MO_PB | VGA_GEN_MO_ER | VGA_GEN_MO_IOA);
1010 	/* Set sequencer clocking and memory mode. */
1011 	REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_CLOCKING_MODE);
1012 	REG_WRITE1(sc, VGA_SEQ_DATA, VGA_SEQ_CM_89);
1013 	REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_MEMORY_MODE);
1014 	REG_WRITE1(sc, VGA_SEQ_DATA, VGA_SEQ_MM_OE | VGA_SEQ_MM_EM);
1015 
1016 	/* Set the graphics controller in graphics mode. */
1017 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_MISCELLANEOUS);
1018 	REG_WRITE1(sc, VGA_GC_DATA, 0x04 + VGA_GC_MISC_GA);
1019 	/* Program the CRT controller. */
1020 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_HORIZ_TOTAL);
1021 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x5f);			/* 760 */
1022 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_HORIZ_DISP_END);
1023 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x4f);			/* 640 - 8 */
1024 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_START_HORIZ_BLANK);
1025 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x50);			/* 640 */
1026 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_END_HORIZ_BLANK);
1027 	REG_WRITE1(sc, VGA_CRTC_DATA, VGA_CRTC_EHB_CR + 2);
1028 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_START_HORIZ_RETRACE);
1029 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x54);			/* 672 */
1030 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_END_HORIZ_RETRACE);
1031 	REG_WRITE1(sc, VGA_CRTC_DATA, VGA_CRTC_EHR_EHB + 0);
1032 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_VERT_TOTAL);
1033 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x0b);			/* 523 */
1034 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_OVERFLOW);
1035 	REG_WRITE1(sc, VGA_CRTC_DATA, VGA_CRTC_OF_VT9 | VGA_CRTC_OF_LC8 |
1036 	    VGA_CRTC_OF_VBS8 | VGA_CRTC_OF_VRS8 | VGA_CRTC_OF_VDE8);
1037 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_MAX_SCAN_LINE);
1038 	REG_WRITE1(sc, VGA_CRTC_DATA, VGA_CRTC_MSL_LC9);
1039 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_VERT_RETRACE_START);
1040 	REG_WRITE1(sc, VGA_CRTC_DATA, 0xea);			/* 480 + 10 */
1041 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_VERT_RETRACE_END);
1042 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x0c);
1043 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_VERT_DISPLAY_END);
1044 	REG_WRITE1(sc, VGA_CRTC_DATA, 0xdf);			/* 480 - 1*/
1045 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_OFFSET);
1046 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x28);
1047 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_START_VERT_BLANK);
1048 	REG_WRITE1(sc, VGA_CRTC_DATA, 0xe7);			/* 480 + 7 */
1049 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_END_VERT_BLANK);
1050 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x04);
1051 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_MODE_CONTROL);
1052 	REG_WRITE1(sc, VGA_CRTC_DATA, VGA_CRTC_MC_WB | VGA_CRTC_MC_AW |
1053 	    VGA_CRTC_MC_SRS | VGA_CRTC_MC_CMS);
1054 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_LINE_COMPARE);
1055 	REG_WRITE1(sc, VGA_CRTC_DATA, 0xff);			/* 480 + 31 */
1056 
1057 	REG_WRITE1(sc, VGA_GEN_FEATURE_CTRL_W, 0);
1058 
1059 	REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_MAP_MASK);
1060 	REG_WRITE1(sc, VGA_SEQ_DATA, VGA_SEQ_MM_EM3 | VGA_SEQ_MM_EM2 |
1061 	    VGA_SEQ_MM_EM1 | VGA_SEQ_MM_EM0);
1062 	REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_CHAR_MAP_SELECT);
1063 	REG_WRITE1(sc, VGA_SEQ_DATA, 0);
1064 
1065 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_SET_RESET);
1066 	REG_WRITE1(sc, VGA_GC_DATA, 0);
1067 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_ENABLE_SET_RESET);
1068 	REG_WRITE1(sc, VGA_GC_DATA, 0x0f);
1069 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_COLOR_COMPARE);
1070 	REG_WRITE1(sc, VGA_GC_DATA, 0);
1071 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_DATA_ROTATE);
1072 	REG_WRITE1(sc, VGA_GC_DATA, 0);
1073 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_READ_MAP_SELECT);
1074 	REG_WRITE1(sc, VGA_GC_DATA, 0);
1075 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_MODE);
1076 	REG_WRITE1(sc, VGA_GC_DATA, 0);
1077 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_COLOR_DONT_CARE);
1078 	REG_WRITE1(sc, VGA_GC_DATA, 0x0f);
1079 	REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_BIT_MASK);
1080 	REG_WRITE1(sc, VGA_GC_DATA, 0xff);
1081 }
1082 
1083 static int
1084 vga_initialize(struct vt_device *vd, int textmode)
1085 {
1086 	struct vga_softc *sc = vd->vd_softc;
1087 	uint8_t x;
1088 	int timeout;
1089 
1090 	/* Make sure the VGA adapter is not in monochrome emulation mode. */
1091 	x = REG_READ1(sc, VGA_GEN_MISC_OUTPUT_R);
1092 	REG_WRITE1(sc, VGA_GEN_MISC_OUTPUT_W, x | VGA_GEN_MO_IOA);
1093 
1094 	/* Unprotect CRTC registers 0-7. */
1095 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_VERT_RETRACE_END);
1096 	x = REG_READ1(sc, VGA_CRTC_DATA);
1097 	REG_WRITE1(sc, VGA_CRTC_DATA, x & ~VGA_CRTC_VRE_PR);
1098 
1099 	/*
1100 	 * Wait for the vertical retrace.
1101 	 * NOTE: this code reads the VGA_GEN_INPUT_STAT_1 register, which has
1102 	 * the side-effect of clearing the internal flip-flip of the attribute
1103 	 * controller's write register. This means that because this code is
1104 	 * here, we know for sure that the first write to the attribute
1105 	 * controller will be a write to the address register. Removing this
1106 	 * code therefore also removes that guarantee and appropriate measures
1107 	 * need to be taken.
1108 	 */
1109 	timeout = 10000;
1110 	do {
1111 		DELAY(10);
1112 		x = REG_READ1(sc, VGA_GEN_INPUT_STAT_1);
1113 		x &= VGA_GEN_IS1_VR | VGA_GEN_IS1_DE;
1114 	} while (x != (VGA_GEN_IS1_VR | VGA_GEN_IS1_DE) && --timeout != 0);
1115 	if (timeout == 0) {
1116 		printf("Timeout initializing vt_vga\n");
1117 		return (ENXIO);
1118 	}
1119 
1120 	/* Now, disable the sync. signals. */
1121 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_MODE_CONTROL);
1122 	x = REG_READ1(sc, VGA_CRTC_DATA);
1123 	REG_WRITE1(sc, VGA_CRTC_DATA, x & ~VGA_CRTC_MC_HR);
1124 
1125 	/* Asynchronous sequencer reset. */
1126 	REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_RESET);
1127 	REG_WRITE1(sc, VGA_SEQ_DATA, VGA_SEQ_RST_SR);
1128 
1129 	if (!textmode)
1130 		vga_initialize_graphics(vd);
1131 
1132 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_PRESET_ROW_SCAN);
1133 	REG_WRITE1(sc, VGA_CRTC_DATA, 0);
1134 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_CURSOR_START);
1135 	REG_WRITE1(sc, VGA_CRTC_DATA, VGA_CRTC_CS_COO);
1136 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_CURSOR_END);
1137 	REG_WRITE1(sc, VGA_CRTC_DATA, 0);
1138 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_START_ADDR_HIGH);
1139 	REG_WRITE1(sc, VGA_CRTC_DATA, 0);
1140 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_START_ADDR_LOW);
1141 	REG_WRITE1(sc, VGA_CRTC_DATA, 0);
1142 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_CURSOR_LOC_HIGH);
1143 	REG_WRITE1(sc, VGA_CRTC_DATA, 0);
1144 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_CURSOR_LOC_LOW);
1145 	REG_WRITE1(sc, VGA_CRTC_DATA, 0x59);
1146 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_UNDERLINE_LOC);
1147 	REG_WRITE1(sc, VGA_CRTC_DATA, VGA_CRTC_UL_UL);
1148 
1149 	if (textmode) {
1150 		/* Set the attribute controller to blink disable. */
1151 		REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_MODE_CONTROL);
1152 		REG_WRITE1(sc, VGA_AC_WRITE, 0);
1153 	} else {
1154 		/* Set the attribute controller in graphics mode. */
1155 		REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_MODE_CONTROL);
1156 		REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_MC_GA);
1157 		REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_HORIZ_PIXEL_PANNING);
1158 		REG_WRITE1(sc, VGA_AC_WRITE, 0);
1159 	}
1160 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(0));
1161 	REG_WRITE1(sc, VGA_AC_WRITE, 0);
1162 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(1));
1163 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_B);
1164 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(2));
1165 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_G);
1166 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(3));
1167 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_G | VGA_AC_PAL_B);
1168 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(4));
1169 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_R);
1170 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(5));
1171 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_R | VGA_AC_PAL_B);
1172 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(6));
1173 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SG | VGA_AC_PAL_R);
1174 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(7));
1175 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_R | VGA_AC_PAL_G | VGA_AC_PAL_B);
1176 
1177 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(8));
1178 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1179 	    VGA_AC_PAL_SB);
1180 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(9));
1181 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1182 	    VGA_AC_PAL_SB | VGA_AC_PAL_B);
1183 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(10));
1184 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1185 	    VGA_AC_PAL_SB | VGA_AC_PAL_G);
1186 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(11));
1187 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1188 	    VGA_AC_PAL_SB | VGA_AC_PAL_G | VGA_AC_PAL_B);
1189 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(12));
1190 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1191 	    VGA_AC_PAL_SB | VGA_AC_PAL_R);
1192 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(13));
1193 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1194 	    VGA_AC_PAL_SB | VGA_AC_PAL_R | VGA_AC_PAL_B);
1195 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(14));
1196 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1197 	    VGA_AC_PAL_SB | VGA_AC_PAL_R | VGA_AC_PAL_G);
1198 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PALETTE(15));
1199 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_PAL_SR | VGA_AC_PAL_SG |
1200 	    VGA_AC_PAL_SB | VGA_AC_PAL_R | VGA_AC_PAL_G | VGA_AC_PAL_B);
1201 
1202 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_OVERSCAN_COLOR);
1203 	REG_WRITE1(sc, VGA_AC_WRITE, 0);
1204 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_COLOR_PLANE_ENABLE);
1205 	REG_WRITE1(sc, VGA_AC_WRITE, 0x0f);
1206 	REG_WRITE1(sc, VGA_AC_WRITE, VGA_AC_COLOR_SELECT);
1207 	REG_WRITE1(sc, VGA_AC_WRITE, 0);
1208 
1209 	if (!textmode) {
1210 		u_int ofs;
1211 
1212 		/*
1213 		 * Done.  Clear the frame buffer.  All bit planes are
1214 		 * enabled, so a single-paged loop should clear all
1215 		 * planes.
1216 		 */
1217 		for (ofs = 0; ofs < VT_VGA_MEMSIZE; ofs++) {
1218 			MEM_WRITE1(sc, ofs, 0);
1219 		}
1220 	}
1221 
1222 	/* Re-enable the sequencer. */
1223 	REG_WRITE1(sc, VGA_SEQ_ADDRESS, VGA_SEQ_RESET);
1224 	REG_WRITE1(sc, VGA_SEQ_DATA, VGA_SEQ_RST_SR | VGA_SEQ_RST_NAR);
1225 	/* Re-enable the sync signals. */
1226 	REG_WRITE1(sc, VGA_CRTC_ADDRESS, VGA_CRTC_MODE_CONTROL);
1227 	x = REG_READ1(sc, VGA_CRTC_DATA);
1228 	REG_WRITE1(sc, VGA_CRTC_DATA, x | VGA_CRTC_MC_HR);
1229 
1230 	if (!textmode) {
1231 		/* Switch to write mode 3, because we'll mainly do bitblt. */
1232 		REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_MODE);
1233 		REG_WRITE1(sc, VGA_GC_DATA, 3);
1234 		sc->vga_wmode = 3;
1235 
1236 		/*
1237 		 * In Write Mode 3, Enable Set/Reset is ignored, but we
1238 		 * use Write Mode 0 to write a group of 8 pixels using
1239 		 * 3 or more colors. In this case, we want to disable
1240 		 * Set/Reset: set Enable Set/Reset to 0.
1241 		 */
1242 		REG_WRITE1(sc, VGA_GC_ADDRESS, VGA_GC_ENABLE_SET_RESET);
1243 		REG_WRITE1(sc, VGA_GC_DATA, 0x00);
1244 
1245 		/*
1246 		 * Clear the colors we think are loaded into Set/Reset or
1247 		 * the latches.
1248 		 */
1249 		sc->vga_curfg = sc->vga_curbg = 0xff;
1250 	}
1251 
1252 	return (0);
1253 }
1254 
1255 static bool
1256 vga_acpi_disabled(void)
1257 {
1258 #if defined(__amd64__) || defined(__i386__)
1259 	uint16_t flags;
1260 	int ignore;
1261 
1262 	/*
1263 	 * Ignore the flag on real hardware: there's a lot of buggy firmware
1264 	 * that will wrongly set it.
1265 	 */
1266 	ignore = (vm_guest == VM_GUEST_NO);
1267 	TUNABLE_INT_FETCH("hw.vga.acpi_ignore_no_vga", &ignore);
1268 	if (ignore || !acpi_get_fadt_bootflags(&flags))
1269  		return (false);
1270 	return ((flags & ACPI_FADT_NO_VGA) != 0);
1271 #else
1272 	return (false);
1273 #endif
1274 }
1275 
1276 static int
1277 vga_probe(struct vt_device *vd)
1278 {
1279 
1280 	return (vga_acpi_disabled() ? CN_DEAD : CN_INTERNAL);
1281 }
1282 
1283 static int
1284 vga_init(struct vt_device *vd)
1285 {
1286 	struct vga_softc *sc;
1287 	int textmode;
1288 
1289 	if (vd->vd_softc == NULL)
1290 		vd->vd_softc = (void *)&vga_conssoftc;
1291 	sc = vd->vd_softc;
1292 
1293 	if (vd->vd_flags & VDF_DOWNGRADE && vd->vd_video_dev != NULL)
1294 		vga_pci_repost(vd->vd_video_dev);
1295 
1296 #if defined(__amd64__) || defined(__i386__)
1297 	sc->vga_fb_tag = X86_BUS_SPACE_MEM;
1298 	sc->vga_reg_tag = X86_BUS_SPACE_IO;
1299 #else
1300 # error "Architecture not yet supported!"
1301 #endif
1302 
1303 	bus_space_map(sc->vga_reg_tag, VGA_REG_BASE, VGA_REG_SIZE, 0,
1304 	    &sc->vga_reg_handle);
1305 
1306 	/*
1307 	 * If "hw.vga.textmode" is not set and we're running on hypervisor,
1308 	 * we use text mode by default, this is because when we're on
1309 	 * hypervisor, vt(4) is usually much slower in graphics mode than
1310 	 * in text mode, especially when we're on Hyper-V.
1311 	 */
1312 	textmode = vm_guest != VM_GUEST_NO;
1313 	TUNABLE_INT_FETCH("hw.vga.textmode", &textmode);
1314 	if (textmode) {
1315 		vd->vd_flags |= VDF_TEXTMODE;
1316 		vd->vd_width = 80;
1317 		vd->vd_height = 25;
1318 		bus_space_map(sc->vga_fb_tag, VGA_TXT_BASE, VGA_TXT_SIZE, 0,
1319 		    &sc->vga_fb_handle);
1320 	} else {
1321 		vd->vd_width = VT_VGA_WIDTH;
1322 		vd->vd_height = VT_VGA_HEIGHT;
1323 		bus_space_map(sc->vga_fb_tag, VGA_MEM_BASE, VGA_MEM_SIZE, 0,
1324 		    &sc->vga_fb_handle);
1325 	}
1326 	if (vga_initialize(vd, textmode) != 0)
1327 		return (CN_DEAD);
1328 	sc->vga_enabled = true;
1329 
1330 	return (CN_INTERNAL);
1331 }
1332 
1333 static void
1334 vga_postswitch(struct vt_device *vd)
1335 {
1336 
1337 	/* Reinit VGA mode, to restore view after app which change mode. */
1338 	vga_initialize(vd, (vd->vd_flags & VDF_TEXTMODE));
1339 	/* Ask vt(9) to update chars on visible area. */
1340 	vd->vd_flags |= VDF_INVALID;
1341 }
1342 
1343 /* Dummy NewBus functions to reserve the resources used by the vt_vga driver */
1344 static void
1345 vtvga_identify(driver_t *driver, device_t parent)
1346 {
1347 
1348 	if (!vga_conssoftc.vga_enabled)
1349 		return;
1350 
1351 	if (BUS_ADD_CHILD(parent, 0, driver->name, 0) == NULL)
1352 		panic("Unable to attach vt_vga console");
1353 }
1354 
1355 static int
1356 vtvga_probe(device_t dev)
1357 {
1358 
1359 	device_set_desc(dev, "VT VGA driver");
1360 
1361 	return (BUS_PROBE_NOWILDCARD);
1362 }
1363 
1364 static int
1365 vtvga_attach(device_t dev)
1366 {
1367 	struct resource *pseudo_phys_res;
1368 	int res_id;
1369 
1370 	res_id = 0;
1371 	pseudo_phys_res = bus_alloc_resource(dev, SYS_RES_MEMORY,
1372 	    &res_id, VGA_MEM_BASE, VGA_MEM_BASE + VGA_MEM_SIZE - 1,
1373 	    VGA_MEM_SIZE, RF_ACTIVE);
1374 	if (pseudo_phys_res == NULL)
1375 		panic("Unable to reserve vt_vga memory");
1376 	return (0);
1377 }
1378 
1379 /*-------------------- Private Device Attachment Data  -----------------------*/
1380 static device_method_t vtvga_methods[] = {
1381 	/* Device interface */
1382 	DEVMETHOD(device_identify,	vtvga_identify),
1383 	DEVMETHOD(device_probe,         vtvga_probe),
1384 	DEVMETHOD(device_attach,        vtvga_attach),
1385 
1386 	DEVMETHOD_END
1387 };
1388 
1389 DEFINE_CLASS_0(vtvga, vtvga_driver, vtvga_methods, 0);
1390 
1391 DRIVER_MODULE(vtvga, nexus, vtvga_driver, NULL, NULL);
1392