xref: /openbmc/qemu/hw/display/vga.c (revision 0dacec87)
1 /*
2  * QEMU VGA Emulator.
3  *
4  * Copyright (c) 2003 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "qemu/osdep.h"
25 #include "qapi/error.h"
26 #include "hw/hw.h"
27 #include "hw/display/vga.h"
28 #include "hw/pci/pci.h"
29 #include "vga_int.h"
30 #include "vga_regs.h"
31 #include "ui/pixel_ops.h"
32 #include "qemu/timer.h"
33 #include "hw/xen/xen.h"
34 #include "trace.h"
35 
36 //#define DEBUG_VGA_MEM
37 //#define DEBUG_VGA_REG
38 
39 /* 16 state changes per vertical frame @60 Hz */
40 #define VGA_TEXT_CURSOR_PERIOD_MS       (1000 * 2 * 16 / 60)
41 
42 /*
43  * Video Graphics Array (VGA)
44  *
45  * Chipset docs for original IBM VGA:
46  * http://www.mcamafia.de/pdf/ibm_vgaxga_trm2.pdf
47  *
48  * FreeVGA site:
49  * http://www.osdever.net/FreeVGA/home.htm
50  *
51  * Standard VGA features and Bochs VBE extensions are implemented.
52  */
53 
54 /* force some bits to zero */
55 const uint8_t sr_mask[8] = {
56     0x03,
57     0x3d,
58     0x0f,
59     0x3f,
60     0x0e,
61     0x00,
62     0x00,
63     0xff,
64 };
65 
66 const uint8_t gr_mask[16] = {
67     0x0f, /* 0x00 */
68     0x0f, /* 0x01 */
69     0x0f, /* 0x02 */
70     0x1f, /* 0x03 */
71     0x03, /* 0x04 */
72     0x7b, /* 0x05 */
73     0x0f, /* 0x06 */
74     0x0f, /* 0x07 */
75     0xff, /* 0x08 */
76     0x00, /* 0x09 */
77     0x00, /* 0x0a */
78     0x00, /* 0x0b */
79     0x00, /* 0x0c */
80     0x00, /* 0x0d */
81     0x00, /* 0x0e */
82     0x00, /* 0x0f */
83 };
84 
85 #define cbswap_32(__x) \
86 ((uint32_t)( \
87 		(((uint32_t)(__x) & (uint32_t)0x000000ffUL) << 24) | \
88 		(((uint32_t)(__x) & (uint32_t)0x0000ff00UL) <<  8) | \
89 		(((uint32_t)(__x) & (uint32_t)0x00ff0000UL) >>  8) | \
90 		(((uint32_t)(__x) & (uint32_t)0xff000000UL) >> 24) ))
91 
92 #ifdef HOST_WORDS_BIGENDIAN
93 #define PAT(x) cbswap_32(x)
94 #else
95 #define PAT(x) (x)
96 #endif
97 
98 #ifdef HOST_WORDS_BIGENDIAN
99 #define BIG 1
100 #else
101 #define BIG 0
102 #endif
103 
104 #ifdef HOST_WORDS_BIGENDIAN
105 #define GET_PLANE(data, p) (((data) >> (24 - (p) * 8)) & 0xff)
106 #else
107 #define GET_PLANE(data, p) (((data) >> ((p) * 8)) & 0xff)
108 #endif
109 
110 static const uint32_t mask16[16] = {
111     PAT(0x00000000),
112     PAT(0x000000ff),
113     PAT(0x0000ff00),
114     PAT(0x0000ffff),
115     PAT(0x00ff0000),
116     PAT(0x00ff00ff),
117     PAT(0x00ffff00),
118     PAT(0x00ffffff),
119     PAT(0xff000000),
120     PAT(0xff0000ff),
121     PAT(0xff00ff00),
122     PAT(0xff00ffff),
123     PAT(0xffff0000),
124     PAT(0xffff00ff),
125     PAT(0xffffff00),
126     PAT(0xffffffff),
127 };
128 
129 #undef PAT
130 
131 #ifdef HOST_WORDS_BIGENDIAN
132 #define PAT(x) (x)
133 #else
134 #define PAT(x) cbswap_32(x)
135 #endif
136 
137 static uint32_t expand4[256];
138 static uint16_t expand2[256];
139 static uint8_t expand4to8[16];
140 
141 static void vbe_update_vgaregs(VGACommonState *s);
142 
143 static inline bool vbe_enabled(VGACommonState *s)
144 {
145     return s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED;
146 }
147 
148 static inline uint8_t sr(VGACommonState *s, int idx)
149 {
150     return vbe_enabled(s) ? s->sr_vbe[idx] : s->sr[idx];
151 }
152 
153 static void vga_update_memory_access(VGACommonState *s)
154 {
155     hwaddr base, offset, size;
156 
157     if (s->legacy_address_space == NULL) {
158         return;
159     }
160 
161     if (s->has_chain4_alias) {
162         memory_region_del_subregion(s->legacy_address_space, &s->chain4_alias);
163         object_unparent(OBJECT(&s->chain4_alias));
164         s->has_chain4_alias = false;
165         s->plane_updated = 0xf;
166     }
167     if ((sr(s, VGA_SEQ_PLANE_WRITE) & VGA_SR02_ALL_PLANES) ==
168         VGA_SR02_ALL_PLANES && sr(s, VGA_SEQ_MEMORY_MODE) & VGA_SR04_CHN_4M) {
169         offset = 0;
170         switch ((s->gr[VGA_GFX_MISC] >> 2) & 3) {
171         case 0:
172             base = 0xa0000;
173             size = 0x20000;
174             break;
175         case 1:
176             base = 0xa0000;
177             size = 0x10000;
178             offset = s->bank_offset;
179             break;
180         case 2:
181             base = 0xb0000;
182             size = 0x8000;
183             break;
184         case 3:
185         default:
186             base = 0xb8000;
187             size = 0x8000;
188             break;
189         }
190         assert(offset + size <= s->vram_size);
191         memory_region_init_alias(&s->chain4_alias, memory_region_owner(&s->vram),
192                                  "vga.chain4", &s->vram, offset, size);
193         memory_region_add_subregion_overlap(s->legacy_address_space, base,
194                                             &s->chain4_alias, 2);
195         s->has_chain4_alias = true;
196     }
197 }
198 
199 static void vga_dumb_update_retrace_info(VGACommonState *s)
200 {
201     (void) s;
202 }
203 
204 static void vga_precise_update_retrace_info(VGACommonState *s)
205 {
206     int htotal_chars;
207     int hretr_start_char;
208     int hretr_skew_chars;
209     int hretr_end_char;
210 
211     int vtotal_lines;
212     int vretr_start_line;
213     int vretr_end_line;
214 
215     int dots;
216 #if 0
217     int div2, sldiv2;
218 #endif
219     int clocking_mode;
220     int clock_sel;
221     const int clk_hz[] = {25175000, 28322000, 25175000, 25175000};
222     int64_t chars_per_sec;
223     struct vga_precise_retrace *r = &s->retrace_info.precise;
224 
225     htotal_chars = s->cr[VGA_CRTC_H_TOTAL] + 5;
226     hretr_start_char = s->cr[VGA_CRTC_H_SYNC_START];
227     hretr_skew_chars = (s->cr[VGA_CRTC_H_SYNC_END] >> 5) & 3;
228     hretr_end_char = s->cr[VGA_CRTC_H_SYNC_END] & 0x1f;
229 
230     vtotal_lines = (s->cr[VGA_CRTC_V_TOTAL] |
231                     (((s->cr[VGA_CRTC_OVERFLOW] & 1) |
232                       ((s->cr[VGA_CRTC_OVERFLOW] >> 4) & 2)) << 8)) + 2;
233     vretr_start_line = s->cr[VGA_CRTC_V_SYNC_START] |
234         ((((s->cr[VGA_CRTC_OVERFLOW] >> 2) & 1) |
235           ((s->cr[VGA_CRTC_OVERFLOW] >> 6) & 2)) << 8);
236     vretr_end_line = s->cr[VGA_CRTC_V_SYNC_END] & 0xf;
237 
238     clocking_mode = (sr(s, VGA_SEQ_CLOCK_MODE) >> 3) & 1;
239     clock_sel = (s->msr >> 2) & 3;
240     dots = (s->msr & 1) ? 8 : 9;
241 
242     chars_per_sec = clk_hz[clock_sel] / dots;
243 
244     htotal_chars <<= clocking_mode;
245 
246     r->total_chars = vtotal_lines * htotal_chars;
247     if (r->freq) {
248         r->ticks_per_char = NANOSECONDS_PER_SECOND / (r->total_chars * r->freq);
249     } else {
250         r->ticks_per_char = NANOSECONDS_PER_SECOND / chars_per_sec;
251     }
252 
253     r->vstart = vretr_start_line;
254     r->vend = r->vstart + vretr_end_line + 1;
255 
256     r->hstart = hretr_start_char + hretr_skew_chars;
257     r->hend = r->hstart + hretr_end_char + 1;
258     r->htotal = htotal_chars;
259 
260 #if 0
261     div2 = (s->cr[VGA_CRTC_MODE] >> 2) & 1;
262     sldiv2 = (s->cr[VGA_CRTC_MODE] >> 3) & 1;
263     printf (
264         "hz=%f\n"
265         "htotal = %d\n"
266         "hretr_start = %d\n"
267         "hretr_skew = %d\n"
268         "hretr_end = %d\n"
269         "vtotal = %d\n"
270         "vretr_start = %d\n"
271         "vretr_end = %d\n"
272         "div2 = %d sldiv2 = %d\n"
273         "clocking_mode = %d\n"
274         "clock_sel = %d %d\n"
275         "dots = %d\n"
276         "ticks/char = %" PRId64 "\n"
277         "\n",
278         (double) NANOSECONDS_PER_SECOND / (r->ticks_per_char * r->total_chars),
279         htotal_chars,
280         hretr_start_char,
281         hretr_skew_chars,
282         hretr_end_char,
283         vtotal_lines,
284         vretr_start_line,
285         vretr_end_line,
286         div2, sldiv2,
287         clocking_mode,
288         clock_sel,
289         clk_hz[clock_sel],
290         dots,
291         r->ticks_per_char
292         );
293 #endif
294 }
295 
296 static uint8_t vga_precise_retrace(VGACommonState *s)
297 {
298     struct vga_precise_retrace *r = &s->retrace_info.precise;
299     uint8_t val = s->st01 & ~(ST01_V_RETRACE | ST01_DISP_ENABLE);
300 
301     if (r->total_chars) {
302         int cur_line, cur_line_char, cur_char;
303         int64_t cur_tick;
304 
305         cur_tick = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
306 
307         cur_char = (cur_tick / r->ticks_per_char) % r->total_chars;
308         cur_line = cur_char / r->htotal;
309 
310         if (cur_line >= r->vstart && cur_line <= r->vend) {
311             val |= ST01_V_RETRACE | ST01_DISP_ENABLE;
312         } else {
313             cur_line_char = cur_char % r->htotal;
314             if (cur_line_char >= r->hstart && cur_line_char <= r->hend) {
315                 val |= ST01_DISP_ENABLE;
316             }
317         }
318 
319         return val;
320     } else {
321         return s->st01 ^ (ST01_V_RETRACE | ST01_DISP_ENABLE);
322     }
323 }
324 
325 static uint8_t vga_dumb_retrace(VGACommonState *s)
326 {
327     return s->st01 ^ (ST01_V_RETRACE | ST01_DISP_ENABLE);
328 }
329 
330 int vga_ioport_invalid(VGACommonState *s, uint32_t addr)
331 {
332     if (s->msr & VGA_MIS_COLOR) {
333         /* Color */
334         return (addr >= 0x3b0 && addr <= 0x3bf);
335     } else {
336         /* Monochrome */
337         return (addr >= 0x3d0 && addr <= 0x3df);
338     }
339 }
340 
341 uint32_t vga_ioport_read(void *opaque, uint32_t addr)
342 {
343     VGACommonState *s = opaque;
344     int val, index;
345 
346     if (vga_ioport_invalid(s, addr)) {
347         val = 0xff;
348     } else {
349         switch(addr) {
350         case VGA_ATT_W:
351             if (s->ar_flip_flop == 0) {
352                 val = s->ar_index;
353             } else {
354                 val = 0;
355             }
356             break;
357         case VGA_ATT_R:
358             index = s->ar_index & 0x1f;
359             if (index < VGA_ATT_C) {
360                 val = s->ar[index];
361             } else {
362                 val = 0;
363             }
364             break;
365         case VGA_MIS_W:
366             val = s->st00;
367             break;
368         case VGA_SEQ_I:
369             val = s->sr_index;
370             break;
371         case VGA_SEQ_D:
372             val = s->sr[s->sr_index];
373 #ifdef DEBUG_VGA_REG
374             printf("vga: read SR%x = 0x%02x\n", s->sr_index, val);
375 #endif
376             break;
377         case VGA_PEL_IR:
378             val = s->dac_state;
379             break;
380         case VGA_PEL_IW:
381             val = s->dac_write_index;
382             break;
383         case VGA_PEL_D:
384             val = s->palette[s->dac_read_index * 3 + s->dac_sub_index];
385             if (++s->dac_sub_index == 3) {
386                 s->dac_sub_index = 0;
387                 s->dac_read_index++;
388             }
389             break;
390         case VGA_FTC_R:
391             val = s->fcr;
392             break;
393         case VGA_MIS_R:
394             val = s->msr;
395             break;
396         case VGA_GFX_I:
397             val = s->gr_index;
398             break;
399         case VGA_GFX_D:
400             val = s->gr[s->gr_index];
401 #ifdef DEBUG_VGA_REG
402             printf("vga: read GR%x = 0x%02x\n", s->gr_index, val);
403 #endif
404             break;
405         case VGA_CRT_IM:
406         case VGA_CRT_IC:
407             val = s->cr_index;
408             break;
409         case VGA_CRT_DM:
410         case VGA_CRT_DC:
411             val = s->cr[s->cr_index];
412 #ifdef DEBUG_VGA_REG
413             printf("vga: read CR%x = 0x%02x\n", s->cr_index, val);
414 #endif
415             break;
416         case VGA_IS1_RM:
417         case VGA_IS1_RC:
418             /* just toggle to fool polling */
419             val = s->st01 = s->retrace(s);
420             s->ar_flip_flop = 0;
421             break;
422         default:
423             val = 0x00;
424             break;
425         }
426     }
427     trace_vga_std_read_io(addr, val);
428     return val;
429 }
430 
431 void vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
432 {
433     VGACommonState *s = opaque;
434     int index;
435 
436     /* check port range access depending on color/monochrome mode */
437     if (vga_ioport_invalid(s, addr)) {
438         return;
439     }
440     trace_vga_std_write_io(addr, val);
441 
442     switch(addr) {
443     case VGA_ATT_W:
444         if (s->ar_flip_flop == 0) {
445             val &= 0x3f;
446             s->ar_index = val;
447         } else {
448             index = s->ar_index & 0x1f;
449             switch(index) {
450             case VGA_ATC_PALETTE0 ... VGA_ATC_PALETTEF:
451                 s->ar[index] = val & 0x3f;
452                 break;
453             case VGA_ATC_MODE:
454                 s->ar[index] = val & ~0x10;
455                 break;
456             case VGA_ATC_OVERSCAN:
457                 s->ar[index] = val;
458                 break;
459             case VGA_ATC_PLANE_ENABLE:
460                 s->ar[index] = val & ~0xc0;
461                 break;
462             case VGA_ATC_PEL:
463                 s->ar[index] = val & ~0xf0;
464                 break;
465             case VGA_ATC_COLOR_PAGE:
466                 s->ar[index] = val & ~0xf0;
467                 break;
468             default:
469                 break;
470             }
471         }
472         s->ar_flip_flop ^= 1;
473         break;
474     case VGA_MIS_W:
475         s->msr = val & ~0x10;
476         s->update_retrace_info(s);
477         break;
478     case VGA_SEQ_I:
479         s->sr_index = val & 7;
480         break;
481     case VGA_SEQ_D:
482 #ifdef DEBUG_VGA_REG
483         printf("vga: write SR%x = 0x%02x\n", s->sr_index, val);
484 #endif
485         s->sr[s->sr_index] = val & sr_mask[s->sr_index];
486         if (s->sr_index == VGA_SEQ_CLOCK_MODE) {
487             s->update_retrace_info(s);
488         }
489         vga_update_memory_access(s);
490         break;
491     case VGA_PEL_IR:
492         s->dac_read_index = val;
493         s->dac_sub_index = 0;
494         s->dac_state = 3;
495         break;
496     case VGA_PEL_IW:
497         s->dac_write_index = val;
498         s->dac_sub_index = 0;
499         s->dac_state = 0;
500         break;
501     case VGA_PEL_D:
502         s->dac_cache[s->dac_sub_index] = val;
503         if (++s->dac_sub_index == 3) {
504             memcpy(&s->palette[s->dac_write_index * 3], s->dac_cache, 3);
505             s->dac_sub_index = 0;
506             s->dac_write_index++;
507         }
508         break;
509     case VGA_GFX_I:
510         s->gr_index = val & 0x0f;
511         break;
512     case VGA_GFX_D:
513 #ifdef DEBUG_VGA_REG
514         printf("vga: write GR%x = 0x%02x\n", s->gr_index, val);
515 #endif
516         s->gr[s->gr_index] = val & gr_mask[s->gr_index];
517         vbe_update_vgaregs(s);
518         vga_update_memory_access(s);
519         break;
520     case VGA_CRT_IM:
521     case VGA_CRT_IC:
522         s->cr_index = val;
523         break;
524     case VGA_CRT_DM:
525     case VGA_CRT_DC:
526 #ifdef DEBUG_VGA_REG
527         printf("vga: write CR%x = 0x%02x\n", s->cr_index, val);
528 #endif
529         /* handle CR0-7 protection */
530         if ((s->cr[VGA_CRTC_V_SYNC_END] & VGA_CR11_LOCK_CR0_CR7) &&
531             s->cr_index <= VGA_CRTC_OVERFLOW) {
532             /* can always write bit 4 of CR7 */
533             if (s->cr_index == VGA_CRTC_OVERFLOW) {
534                 s->cr[VGA_CRTC_OVERFLOW] = (s->cr[VGA_CRTC_OVERFLOW] & ~0x10) |
535                     (val & 0x10);
536                 vbe_update_vgaregs(s);
537             }
538             return;
539         }
540         s->cr[s->cr_index] = val;
541         vbe_update_vgaregs(s);
542 
543         switch(s->cr_index) {
544         case VGA_CRTC_H_TOTAL:
545         case VGA_CRTC_H_SYNC_START:
546         case VGA_CRTC_H_SYNC_END:
547         case VGA_CRTC_V_TOTAL:
548         case VGA_CRTC_OVERFLOW:
549         case VGA_CRTC_V_SYNC_END:
550         case VGA_CRTC_MODE:
551             s->update_retrace_info(s);
552             break;
553         }
554         break;
555     case VGA_IS1_RM:
556     case VGA_IS1_RC:
557         s->fcr = val & 0x10;
558         break;
559     }
560 }
561 
562 /*
563  * Sanity check vbe register writes.
564  *
565  * As we don't have a way to signal errors to the guest in the bochs
566  * dispi interface we'll go adjust the registers to the closest valid
567  * value.
568  */
569 static void vbe_fixup_regs(VGACommonState *s)
570 {
571     uint16_t *r = s->vbe_regs;
572     uint32_t bits, linelength, maxy, offset;
573 
574     if (!vbe_enabled(s)) {
575         /* vbe is turned off -- nothing to do */
576         return;
577     }
578 
579     /* check depth */
580     switch (r[VBE_DISPI_INDEX_BPP]) {
581     case 4:
582     case 8:
583     case 16:
584     case 24:
585     case 32:
586         bits = r[VBE_DISPI_INDEX_BPP];
587         break;
588     case 15:
589         bits = 16;
590         break;
591     default:
592         bits = r[VBE_DISPI_INDEX_BPP] = 8;
593         break;
594     }
595 
596     /* check width */
597     r[VBE_DISPI_INDEX_XRES] &= ~7u;
598     if (r[VBE_DISPI_INDEX_XRES] == 0) {
599         r[VBE_DISPI_INDEX_XRES] = 8;
600     }
601     if (r[VBE_DISPI_INDEX_XRES] > VBE_DISPI_MAX_XRES) {
602         r[VBE_DISPI_INDEX_XRES] = VBE_DISPI_MAX_XRES;
603     }
604     r[VBE_DISPI_INDEX_VIRT_WIDTH] &= ~7u;
605     if (r[VBE_DISPI_INDEX_VIRT_WIDTH] > VBE_DISPI_MAX_XRES) {
606         r[VBE_DISPI_INDEX_VIRT_WIDTH] = VBE_DISPI_MAX_XRES;
607     }
608     if (r[VBE_DISPI_INDEX_VIRT_WIDTH] < r[VBE_DISPI_INDEX_XRES]) {
609         r[VBE_DISPI_INDEX_VIRT_WIDTH] = r[VBE_DISPI_INDEX_XRES];
610     }
611 
612     /* check height */
613     linelength = r[VBE_DISPI_INDEX_VIRT_WIDTH] * bits / 8;
614     maxy = s->vbe_size / linelength;
615     if (r[VBE_DISPI_INDEX_YRES] == 0) {
616         r[VBE_DISPI_INDEX_YRES] = 1;
617     }
618     if (r[VBE_DISPI_INDEX_YRES] > VBE_DISPI_MAX_YRES) {
619         r[VBE_DISPI_INDEX_YRES] = VBE_DISPI_MAX_YRES;
620     }
621     if (r[VBE_DISPI_INDEX_YRES] > maxy) {
622         r[VBE_DISPI_INDEX_YRES] = maxy;
623     }
624 
625     /* check offset */
626     if (r[VBE_DISPI_INDEX_X_OFFSET] > VBE_DISPI_MAX_XRES) {
627         r[VBE_DISPI_INDEX_X_OFFSET] = VBE_DISPI_MAX_XRES;
628     }
629     if (r[VBE_DISPI_INDEX_Y_OFFSET] > VBE_DISPI_MAX_YRES) {
630         r[VBE_DISPI_INDEX_Y_OFFSET] = VBE_DISPI_MAX_YRES;
631     }
632     offset = r[VBE_DISPI_INDEX_X_OFFSET] * bits / 8;
633     offset += r[VBE_DISPI_INDEX_Y_OFFSET] * linelength;
634     if (offset + r[VBE_DISPI_INDEX_YRES] * linelength > s->vbe_size) {
635         r[VBE_DISPI_INDEX_Y_OFFSET] = 0;
636         offset = r[VBE_DISPI_INDEX_X_OFFSET] * bits / 8;
637         if (offset + r[VBE_DISPI_INDEX_YRES] * linelength > s->vbe_size) {
638             r[VBE_DISPI_INDEX_X_OFFSET] = 0;
639             offset = 0;
640         }
641     }
642 
643     /* update vga state */
644     r[VBE_DISPI_INDEX_VIRT_HEIGHT] = maxy;
645     s->vbe_line_offset = linelength;
646     s->vbe_start_addr  = offset / 4;
647 }
648 
649 /* we initialize the VGA graphic mode */
650 static void vbe_update_vgaregs(VGACommonState *s)
651 {
652     int h, shift_control;
653 
654     if (!vbe_enabled(s)) {
655         /* vbe is turned off -- nothing to do */
656         return;
657     }
658 
659     /* graphic mode + memory map 1 */
660     s->gr[VGA_GFX_MISC] = (s->gr[VGA_GFX_MISC] & ~0x0c) | 0x04 |
661         VGA_GR06_GRAPHICS_MODE;
662     s->cr[VGA_CRTC_MODE] |= 3; /* no CGA modes */
663     s->cr[VGA_CRTC_OFFSET] = s->vbe_line_offset >> 3;
664     /* width */
665     s->cr[VGA_CRTC_H_DISP] =
666         (s->vbe_regs[VBE_DISPI_INDEX_XRES] >> 3) - 1;
667     /* height (only meaningful if < 1024) */
668     h = s->vbe_regs[VBE_DISPI_INDEX_YRES] - 1;
669     s->cr[VGA_CRTC_V_DISP_END] = h;
670     s->cr[VGA_CRTC_OVERFLOW] = (s->cr[VGA_CRTC_OVERFLOW] & ~0x42) |
671         ((h >> 7) & 0x02) | ((h >> 3) & 0x40);
672     /* line compare to 1023 */
673     s->cr[VGA_CRTC_LINE_COMPARE] = 0xff;
674     s->cr[VGA_CRTC_OVERFLOW] |= 0x10;
675     s->cr[VGA_CRTC_MAX_SCAN] |= 0x40;
676 
677     if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4) {
678         shift_control = 0;
679         s->sr_vbe[VGA_SEQ_CLOCK_MODE] &= ~8; /* no double line */
680     } else {
681         shift_control = 2;
682         /* set chain 4 mode */
683         s->sr_vbe[VGA_SEQ_MEMORY_MODE] |= VGA_SR04_CHN_4M;
684         /* activate all planes */
685         s->sr_vbe[VGA_SEQ_PLANE_WRITE] |= VGA_SR02_ALL_PLANES;
686     }
687     s->gr[VGA_GFX_MODE] = (s->gr[VGA_GFX_MODE] & ~0x60) |
688         (shift_control << 5);
689     s->cr[VGA_CRTC_MAX_SCAN] &= ~0x9f; /* no double scan */
690 }
691 
692 static uint32_t vbe_ioport_read_index(void *opaque, uint32_t addr)
693 {
694     VGACommonState *s = opaque;
695     return s->vbe_index;
696 }
697 
698 uint32_t vbe_ioport_read_data(void *opaque, uint32_t addr)
699 {
700     VGACommonState *s = opaque;
701     uint32_t val;
702 
703     if (s->vbe_index < VBE_DISPI_INDEX_NB) {
704         if (s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_GETCAPS) {
705             switch(s->vbe_index) {
706                 /* XXX: do not hardcode ? */
707             case VBE_DISPI_INDEX_XRES:
708                 val = VBE_DISPI_MAX_XRES;
709                 break;
710             case VBE_DISPI_INDEX_YRES:
711                 val = VBE_DISPI_MAX_YRES;
712                 break;
713             case VBE_DISPI_INDEX_BPP:
714                 val = VBE_DISPI_MAX_BPP;
715                 break;
716             default:
717                 val = s->vbe_regs[s->vbe_index];
718                 break;
719             }
720         } else {
721             val = s->vbe_regs[s->vbe_index];
722         }
723     } else if (s->vbe_index == VBE_DISPI_INDEX_VIDEO_MEMORY_64K) {
724         val = s->vbe_size / (64 * 1024);
725     } else {
726         val = 0;
727     }
728     trace_vga_vbe_read(s->vbe_index, val);
729     return val;
730 }
731 
732 void vbe_ioport_write_index(void *opaque, uint32_t addr, uint32_t val)
733 {
734     VGACommonState *s = opaque;
735     s->vbe_index = val;
736 }
737 
738 void vbe_ioport_write_data(void *opaque, uint32_t addr, uint32_t val)
739 {
740     VGACommonState *s = opaque;
741 
742     if (s->vbe_index <= VBE_DISPI_INDEX_NB) {
743         trace_vga_vbe_write(s->vbe_index, val);
744         switch(s->vbe_index) {
745         case VBE_DISPI_INDEX_ID:
746             if (val == VBE_DISPI_ID0 ||
747                 val == VBE_DISPI_ID1 ||
748                 val == VBE_DISPI_ID2 ||
749                 val == VBE_DISPI_ID3 ||
750                 val == VBE_DISPI_ID4) {
751                 s->vbe_regs[s->vbe_index] = val;
752             }
753             break;
754         case VBE_DISPI_INDEX_XRES:
755         case VBE_DISPI_INDEX_YRES:
756         case VBE_DISPI_INDEX_BPP:
757         case VBE_DISPI_INDEX_VIRT_WIDTH:
758         case VBE_DISPI_INDEX_X_OFFSET:
759         case VBE_DISPI_INDEX_Y_OFFSET:
760             s->vbe_regs[s->vbe_index] = val;
761             vbe_fixup_regs(s);
762             vbe_update_vgaregs(s);
763             break;
764         case VBE_DISPI_INDEX_BANK:
765             val &= s->vbe_bank_mask;
766             s->vbe_regs[s->vbe_index] = val;
767             s->bank_offset = (val << 16);
768             vga_update_memory_access(s);
769             break;
770         case VBE_DISPI_INDEX_ENABLE:
771             if ((val & VBE_DISPI_ENABLED) &&
772                 !(s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED)) {
773 
774                 s->vbe_regs[VBE_DISPI_INDEX_VIRT_WIDTH] = 0;
775                 s->vbe_regs[VBE_DISPI_INDEX_X_OFFSET] = 0;
776                 s->vbe_regs[VBE_DISPI_INDEX_Y_OFFSET] = 0;
777                 s->vbe_regs[VBE_DISPI_INDEX_ENABLE] |= VBE_DISPI_ENABLED;
778                 vbe_fixup_regs(s);
779                 vbe_update_vgaregs(s);
780 
781                 /* clear the screen */
782                 if (!(val & VBE_DISPI_NOCLEARMEM)) {
783                     memset(s->vram_ptr, 0,
784                            s->vbe_regs[VBE_DISPI_INDEX_YRES] * s->vbe_line_offset);
785                 }
786             } else {
787                 s->bank_offset = 0;
788             }
789             s->dac_8bit = (val & VBE_DISPI_8BIT_DAC) > 0;
790             s->vbe_regs[s->vbe_index] = val;
791             vga_update_memory_access(s);
792             break;
793         default:
794             break;
795         }
796     }
797 }
798 
799 /* called for accesses between 0xa0000 and 0xc0000 */
800 uint32_t vga_mem_readb(VGACommonState *s, hwaddr addr)
801 {
802     int memory_map_mode, plane;
803     uint32_t ret;
804 
805     /* convert to VGA memory offset */
806     memory_map_mode = (s->gr[VGA_GFX_MISC] >> 2) & 3;
807     addr &= 0x1ffff;
808     switch(memory_map_mode) {
809     case 0:
810         break;
811     case 1:
812         if (addr >= 0x10000)
813             return 0xff;
814         addr += s->bank_offset;
815         break;
816     case 2:
817         addr -= 0x10000;
818         if (addr >= 0x8000)
819             return 0xff;
820         break;
821     default:
822     case 3:
823         addr -= 0x18000;
824         if (addr >= 0x8000)
825             return 0xff;
826         break;
827     }
828 
829     if (sr(s, VGA_SEQ_MEMORY_MODE) & VGA_SR04_CHN_4M) {
830         /* chain 4 mode : simplest access */
831         assert(addr < s->vram_size);
832         ret = s->vram_ptr[addr];
833     } else if (s->gr[VGA_GFX_MODE] & 0x10) {
834         /* odd/even mode (aka text mode mapping) */
835         plane = (s->gr[VGA_GFX_PLANE_READ] & 2) | (addr & 1);
836         addr = ((addr & ~1) << 1) | plane;
837         if (addr >= s->vram_size) {
838             return 0xff;
839         }
840         ret = s->vram_ptr[addr];
841     } else {
842         /* standard VGA latched access */
843         if (addr * sizeof(uint32_t) >= s->vram_size) {
844             return 0xff;
845         }
846         s->latch = ((uint32_t *)s->vram_ptr)[addr];
847 
848         if (!(s->gr[VGA_GFX_MODE] & 0x08)) {
849             /* read mode 0 */
850             plane = s->gr[VGA_GFX_PLANE_READ];
851             ret = GET_PLANE(s->latch, plane);
852         } else {
853             /* read mode 1 */
854             ret = (s->latch ^ mask16[s->gr[VGA_GFX_COMPARE_VALUE]]) &
855                 mask16[s->gr[VGA_GFX_COMPARE_MASK]];
856             ret |= ret >> 16;
857             ret |= ret >> 8;
858             ret = (~ret) & 0xff;
859         }
860     }
861     return ret;
862 }
863 
864 /* called for accesses between 0xa0000 and 0xc0000 */
865 void vga_mem_writeb(VGACommonState *s, hwaddr addr, uint32_t val)
866 {
867     int memory_map_mode, plane, write_mode, b, func_select, mask;
868     uint32_t write_mask, bit_mask, set_mask;
869 
870 #ifdef DEBUG_VGA_MEM
871     printf("vga: [0x" TARGET_FMT_plx "] = 0x%02x\n", addr, val);
872 #endif
873     /* convert to VGA memory offset */
874     memory_map_mode = (s->gr[VGA_GFX_MISC] >> 2) & 3;
875     addr &= 0x1ffff;
876     switch(memory_map_mode) {
877     case 0:
878         break;
879     case 1:
880         if (addr >= 0x10000)
881             return;
882         addr += s->bank_offset;
883         break;
884     case 2:
885         addr -= 0x10000;
886         if (addr >= 0x8000)
887             return;
888         break;
889     default:
890     case 3:
891         addr -= 0x18000;
892         if (addr >= 0x8000)
893             return;
894         break;
895     }
896 
897     if (sr(s, VGA_SEQ_MEMORY_MODE) & VGA_SR04_CHN_4M) {
898         /* chain 4 mode : simplest access */
899         plane = addr & 3;
900         mask = (1 << plane);
901         if (sr(s, VGA_SEQ_PLANE_WRITE) & mask) {
902             assert(addr < s->vram_size);
903             s->vram_ptr[addr] = val;
904 #ifdef DEBUG_VGA_MEM
905             printf("vga: chain4: [0x" TARGET_FMT_plx "]\n", addr);
906 #endif
907             s->plane_updated |= mask; /* only used to detect font change */
908             memory_region_set_dirty(&s->vram, addr, 1);
909         }
910     } else if (s->gr[VGA_GFX_MODE] & 0x10) {
911         /* odd/even mode (aka text mode mapping) */
912         plane = (s->gr[VGA_GFX_PLANE_READ] & 2) | (addr & 1);
913         mask = (1 << plane);
914         if (sr(s, VGA_SEQ_PLANE_WRITE) & mask) {
915             addr = ((addr & ~1) << 1) | plane;
916             if (addr >= s->vram_size) {
917                 return;
918             }
919             s->vram_ptr[addr] = val;
920 #ifdef DEBUG_VGA_MEM
921             printf("vga: odd/even: [0x" TARGET_FMT_plx "]\n", addr);
922 #endif
923             s->plane_updated |= mask; /* only used to detect font change */
924             memory_region_set_dirty(&s->vram, addr, 1);
925         }
926     } else {
927         /* standard VGA latched access */
928         write_mode = s->gr[VGA_GFX_MODE] & 3;
929         switch(write_mode) {
930         default:
931         case 0:
932             /* rotate */
933             b = s->gr[VGA_GFX_DATA_ROTATE] & 7;
934             val = ((val >> b) | (val << (8 - b))) & 0xff;
935             val |= val << 8;
936             val |= val << 16;
937 
938             /* apply set/reset mask */
939             set_mask = mask16[s->gr[VGA_GFX_SR_ENABLE]];
940             val = (val & ~set_mask) |
941                 (mask16[s->gr[VGA_GFX_SR_VALUE]] & set_mask);
942             bit_mask = s->gr[VGA_GFX_BIT_MASK];
943             break;
944         case 1:
945             val = s->latch;
946             goto do_write;
947         case 2:
948             val = mask16[val & 0x0f];
949             bit_mask = s->gr[VGA_GFX_BIT_MASK];
950             break;
951         case 3:
952             /* rotate */
953             b = s->gr[VGA_GFX_DATA_ROTATE] & 7;
954             val = (val >> b) | (val << (8 - b));
955 
956             bit_mask = s->gr[VGA_GFX_BIT_MASK] & val;
957             val = mask16[s->gr[VGA_GFX_SR_VALUE]];
958             break;
959         }
960 
961         /* apply logical operation */
962         func_select = s->gr[VGA_GFX_DATA_ROTATE] >> 3;
963         switch(func_select) {
964         case 0:
965         default:
966             /* nothing to do */
967             break;
968         case 1:
969             /* and */
970             val &= s->latch;
971             break;
972         case 2:
973             /* or */
974             val |= s->latch;
975             break;
976         case 3:
977             /* xor */
978             val ^= s->latch;
979             break;
980         }
981 
982         /* apply bit mask */
983         bit_mask |= bit_mask << 8;
984         bit_mask |= bit_mask << 16;
985         val = (val & bit_mask) | (s->latch & ~bit_mask);
986 
987     do_write:
988         /* mask data according to sr[2] */
989         mask = sr(s, VGA_SEQ_PLANE_WRITE);
990         s->plane_updated |= mask; /* only used to detect font change */
991         write_mask = mask16[mask];
992         if (addr * sizeof(uint32_t) >= s->vram_size) {
993             return;
994         }
995         ((uint32_t *)s->vram_ptr)[addr] =
996             (((uint32_t *)s->vram_ptr)[addr] & ~write_mask) |
997             (val & write_mask);
998 #ifdef DEBUG_VGA_MEM
999         printf("vga: latch: [0x" TARGET_FMT_plx "] mask=0x%08x val=0x%08x\n",
1000                addr * 4, write_mask, val);
1001 #endif
1002         memory_region_set_dirty(&s->vram, addr << 2, sizeof(uint32_t));
1003     }
1004 }
1005 
1006 typedef void vga_draw_line_func(VGACommonState *s1, uint8_t *d,
1007                                 uint32_t srcaddr, int width);
1008 
1009 #include "vga-helpers.h"
1010 
1011 /* return true if the palette was modified */
1012 static int update_palette16(VGACommonState *s)
1013 {
1014     int full_update, i;
1015     uint32_t v, col, *palette;
1016 
1017     full_update = 0;
1018     palette = s->last_palette;
1019     for(i = 0; i < 16; i++) {
1020         v = s->ar[i];
1021         if (s->ar[VGA_ATC_MODE] & 0x80) {
1022             v = ((s->ar[VGA_ATC_COLOR_PAGE] & 0xf) << 4) | (v & 0xf);
1023         } else {
1024             v = ((s->ar[VGA_ATC_COLOR_PAGE] & 0xc) << 4) | (v & 0x3f);
1025         }
1026         v = v * 3;
1027         col = rgb_to_pixel32(c6_to_8(s->palette[v]),
1028                              c6_to_8(s->palette[v + 1]),
1029                              c6_to_8(s->palette[v + 2]));
1030         if (col != palette[i]) {
1031             full_update = 1;
1032             palette[i] = col;
1033         }
1034     }
1035     return full_update;
1036 }
1037 
1038 /* return true if the palette was modified */
1039 static int update_palette256(VGACommonState *s)
1040 {
1041     int full_update, i;
1042     uint32_t v, col, *palette;
1043 
1044     full_update = 0;
1045     palette = s->last_palette;
1046     v = 0;
1047     for(i = 0; i < 256; i++) {
1048         if (s->dac_8bit) {
1049             col = rgb_to_pixel32(s->palette[v],
1050                                  s->palette[v + 1],
1051                                  s->palette[v + 2]);
1052         } else {
1053             col = rgb_to_pixel32(c6_to_8(s->palette[v]),
1054                                  c6_to_8(s->palette[v + 1]),
1055                                  c6_to_8(s->palette[v + 2]));
1056         }
1057         if (col != palette[i]) {
1058             full_update = 1;
1059             palette[i] = col;
1060         }
1061         v += 3;
1062     }
1063     return full_update;
1064 }
1065 
1066 static void vga_get_offsets(VGACommonState *s,
1067                             uint32_t *pline_offset,
1068                             uint32_t *pstart_addr,
1069                             uint32_t *pline_compare)
1070 {
1071     uint32_t start_addr, line_offset, line_compare;
1072 
1073     if (vbe_enabled(s)) {
1074         line_offset = s->vbe_line_offset;
1075         start_addr = s->vbe_start_addr;
1076         line_compare = 65535;
1077     } else {
1078         /* compute line_offset in bytes */
1079         line_offset = s->cr[VGA_CRTC_OFFSET];
1080         line_offset <<= 3;
1081 
1082         /* starting address */
1083         start_addr = s->cr[VGA_CRTC_START_LO] |
1084             (s->cr[VGA_CRTC_START_HI] << 8);
1085 
1086         /* line compare */
1087         line_compare = s->cr[VGA_CRTC_LINE_COMPARE] |
1088             ((s->cr[VGA_CRTC_OVERFLOW] & 0x10) << 4) |
1089             ((s->cr[VGA_CRTC_MAX_SCAN] & 0x40) << 3);
1090     }
1091     *pline_offset = line_offset;
1092     *pstart_addr = start_addr;
1093     *pline_compare = line_compare;
1094 }
1095 
1096 /* update start_addr and line_offset. Return TRUE if modified */
1097 static int update_basic_params(VGACommonState *s)
1098 {
1099     int full_update;
1100     uint32_t start_addr, line_offset, line_compare;
1101 
1102     full_update = 0;
1103 
1104     s->get_offsets(s, &line_offset, &start_addr, &line_compare);
1105 
1106     if (line_offset != s->line_offset ||
1107         start_addr != s->start_addr ||
1108         line_compare != s->line_compare) {
1109         s->line_offset = line_offset;
1110         s->start_addr = start_addr;
1111         s->line_compare = line_compare;
1112         full_update = 1;
1113     }
1114     return full_update;
1115 }
1116 
1117 
1118 static const uint8_t cursor_glyph[32 * 4] = {
1119     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1120     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1121     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1122     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1123     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1124     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1125     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1126     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1127     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1128     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1129     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1130     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1131     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1132     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1133     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1134     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
1135 };
1136 
1137 static void vga_get_text_resolution(VGACommonState *s, int *pwidth, int *pheight,
1138                                     int *pcwidth, int *pcheight)
1139 {
1140     int width, cwidth, height, cheight;
1141 
1142     /* total width & height */
1143     cheight = (s->cr[VGA_CRTC_MAX_SCAN] & 0x1f) + 1;
1144     cwidth = 8;
1145     if (!(sr(s, VGA_SEQ_CLOCK_MODE) & VGA_SR01_CHAR_CLK_8DOTS)) {
1146         cwidth = 9;
1147     }
1148     if (sr(s, VGA_SEQ_CLOCK_MODE) & 0x08) {
1149         cwidth = 16; /* NOTE: no 18 pixel wide */
1150     }
1151     width = (s->cr[VGA_CRTC_H_DISP] + 1);
1152     if (s->cr[VGA_CRTC_V_TOTAL] == 100) {
1153         /* ugly hack for CGA 160x100x16 - explain me the logic */
1154         height = 100;
1155     } else {
1156         height = s->cr[VGA_CRTC_V_DISP_END] |
1157             ((s->cr[VGA_CRTC_OVERFLOW] & 0x02) << 7) |
1158             ((s->cr[VGA_CRTC_OVERFLOW] & 0x40) << 3);
1159         height = (height + 1) / cheight;
1160     }
1161 
1162     *pwidth = width;
1163     *pheight = height;
1164     *pcwidth = cwidth;
1165     *pcheight = cheight;
1166 }
1167 
1168 /*
1169  * Text mode update
1170  * Missing:
1171  * - double scan
1172  * - double width
1173  * - underline
1174  * - flashing
1175  */
1176 static void vga_draw_text(VGACommonState *s, int full_update)
1177 {
1178     DisplaySurface *surface = qemu_console_surface(s->con);
1179     int cx, cy, cheight, cw, ch, cattr, height, width, ch_attr;
1180     int cx_min, cx_max, linesize, x_incr, line, line1;
1181     uint32_t offset, fgcol, bgcol, v, cursor_offset;
1182     uint8_t *d1, *d, *src, *dest, *cursor_ptr;
1183     const uint8_t *font_ptr, *font_base[2];
1184     int dup9, line_offset;
1185     uint32_t *palette;
1186     uint32_t *ch_attr_ptr;
1187     int64_t now = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
1188 
1189     /* compute font data address (in plane 2) */
1190     v = sr(s, VGA_SEQ_CHARACTER_MAP);
1191     offset = (((v >> 4) & 1) | ((v << 1) & 6)) * 8192 * 4 + 2;
1192     if (offset != s->font_offsets[0]) {
1193         s->font_offsets[0] = offset;
1194         full_update = 1;
1195     }
1196     font_base[0] = s->vram_ptr + offset;
1197 
1198     offset = (((v >> 5) & 1) | ((v >> 1) & 6)) * 8192 * 4 + 2;
1199     font_base[1] = s->vram_ptr + offset;
1200     if (offset != s->font_offsets[1]) {
1201         s->font_offsets[1] = offset;
1202         full_update = 1;
1203     }
1204     if (s->plane_updated & (1 << 2) || s->has_chain4_alias) {
1205         /* if the plane 2 was modified since the last display, it
1206            indicates the font may have been modified */
1207         s->plane_updated = 0;
1208         full_update = 1;
1209     }
1210     full_update |= update_basic_params(s);
1211 
1212     line_offset = s->line_offset;
1213 
1214     vga_get_text_resolution(s, &width, &height, &cw, &cheight);
1215     if ((height * width) <= 1) {
1216         /* better than nothing: exit if transient size is too small */
1217         return;
1218     }
1219     if ((height * width) > CH_ATTR_SIZE) {
1220         /* better than nothing: exit if transient size is too big */
1221         return;
1222     }
1223 
1224     if (width != s->last_width || height != s->last_height ||
1225         cw != s->last_cw || cheight != s->last_ch || s->last_depth) {
1226         s->last_scr_width = width * cw;
1227         s->last_scr_height = height * cheight;
1228         qemu_console_resize(s->con, s->last_scr_width, s->last_scr_height);
1229         surface = qemu_console_surface(s->con);
1230         dpy_text_resize(s->con, width, height);
1231         s->last_depth = 0;
1232         s->last_width = width;
1233         s->last_height = height;
1234         s->last_ch = cheight;
1235         s->last_cw = cw;
1236         full_update = 1;
1237     }
1238     full_update |= update_palette16(s);
1239     palette = s->last_palette;
1240     x_incr = cw * surface_bytes_per_pixel(surface);
1241 
1242     if (full_update) {
1243         s->full_update_text = 1;
1244     }
1245     if (s->full_update_gfx) {
1246         s->full_update_gfx = 0;
1247         full_update |= 1;
1248     }
1249 
1250     cursor_offset = ((s->cr[VGA_CRTC_CURSOR_HI] << 8) |
1251                      s->cr[VGA_CRTC_CURSOR_LO]) - s->start_addr;
1252     if (cursor_offset != s->cursor_offset ||
1253         s->cr[VGA_CRTC_CURSOR_START] != s->cursor_start ||
1254         s->cr[VGA_CRTC_CURSOR_END] != s->cursor_end) {
1255       /* if the cursor position changed, we update the old and new
1256          chars */
1257         if (s->cursor_offset < CH_ATTR_SIZE)
1258             s->last_ch_attr[s->cursor_offset] = -1;
1259         if (cursor_offset < CH_ATTR_SIZE)
1260             s->last_ch_attr[cursor_offset] = -1;
1261         s->cursor_offset = cursor_offset;
1262         s->cursor_start = s->cr[VGA_CRTC_CURSOR_START];
1263         s->cursor_end = s->cr[VGA_CRTC_CURSOR_END];
1264     }
1265     cursor_ptr = s->vram_ptr + (s->start_addr + cursor_offset) * 4;
1266     if (now >= s->cursor_blink_time) {
1267         s->cursor_blink_time = now + VGA_TEXT_CURSOR_PERIOD_MS / 2;
1268         s->cursor_visible_phase = !s->cursor_visible_phase;
1269     }
1270 
1271     dest = surface_data(surface);
1272     linesize = surface_stride(surface);
1273     ch_attr_ptr = s->last_ch_attr;
1274     line = 0;
1275     offset = s->start_addr * 4;
1276     for(cy = 0; cy < height; cy++) {
1277         d1 = dest;
1278         src = s->vram_ptr + offset;
1279         cx_min = width;
1280         cx_max = -1;
1281         for(cx = 0; cx < width; cx++) {
1282             if (src + sizeof(uint16_t) > s->vram_ptr + s->vram_size) {
1283                 break;
1284             }
1285             ch_attr = *(uint16_t *)src;
1286             if (full_update || ch_attr != *ch_attr_ptr || src == cursor_ptr) {
1287                 if (cx < cx_min)
1288                     cx_min = cx;
1289                 if (cx > cx_max)
1290                     cx_max = cx;
1291                 *ch_attr_ptr = ch_attr;
1292 #ifdef HOST_WORDS_BIGENDIAN
1293                 ch = ch_attr >> 8;
1294                 cattr = ch_attr & 0xff;
1295 #else
1296                 ch = ch_attr & 0xff;
1297                 cattr = ch_attr >> 8;
1298 #endif
1299                 font_ptr = font_base[(cattr >> 3) & 1];
1300                 font_ptr += 32 * 4 * ch;
1301                 bgcol = palette[cattr >> 4];
1302                 fgcol = palette[cattr & 0x0f];
1303                 if (cw == 16) {
1304                     vga_draw_glyph16(d1, linesize,
1305                                      font_ptr, cheight, fgcol, bgcol);
1306                 } else if (cw != 9) {
1307                     vga_draw_glyph8(d1, linesize,
1308                                     font_ptr, cheight, fgcol, bgcol);
1309                 } else {
1310                     dup9 = 0;
1311                     if (ch >= 0xb0 && ch <= 0xdf &&
1312                         (s->ar[VGA_ATC_MODE] & 0x04)) {
1313                         dup9 = 1;
1314                     }
1315                     vga_draw_glyph9(d1, linesize,
1316                                     font_ptr, cheight, fgcol, bgcol, dup9);
1317                 }
1318                 if (src == cursor_ptr &&
1319                     !(s->cr[VGA_CRTC_CURSOR_START] & 0x20) &&
1320                     s->cursor_visible_phase) {
1321                     int line_start, line_last, h;
1322                     /* draw the cursor */
1323                     line_start = s->cr[VGA_CRTC_CURSOR_START] & 0x1f;
1324                     line_last = s->cr[VGA_CRTC_CURSOR_END] & 0x1f;
1325                     /* XXX: check that */
1326                     if (line_last > cheight - 1)
1327                         line_last = cheight - 1;
1328                     if (line_last >= line_start && line_start < cheight) {
1329                         h = line_last - line_start + 1;
1330                         d = d1 + linesize * line_start;
1331                         if (cw == 16) {
1332                             vga_draw_glyph16(d, linesize,
1333                                              cursor_glyph, h, fgcol, bgcol);
1334                         } else if (cw != 9) {
1335                             vga_draw_glyph8(d, linesize,
1336                                             cursor_glyph, h, fgcol, bgcol);
1337                         } else {
1338                             vga_draw_glyph9(d, linesize,
1339                                             cursor_glyph, h, fgcol, bgcol, 1);
1340                         }
1341                     }
1342                 }
1343             }
1344             d1 += x_incr;
1345             src += 4;
1346             ch_attr_ptr++;
1347         }
1348         if (cx_max != -1) {
1349             dpy_gfx_update(s->con, cx_min * cw, cy * cheight,
1350                            (cx_max - cx_min + 1) * cw, cheight);
1351         }
1352         dest += linesize * cheight;
1353         line1 = line + cheight;
1354         offset += line_offset;
1355         if (line < s->line_compare && line1 >= s->line_compare) {
1356             offset = 0;
1357         }
1358         line = line1;
1359     }
1360 }
1361 
1362 enum {
1363     VGA_DRAW_LINE2,
1364     VGA_DRAW_LINE2D2,
1365     VGA_DRAW_LINE4,
1366     VGA_DRAW_LINE4D2,
1367     VGA_DRAW_LINE8D2,
1368     VGA_DRAW_LINE8,
1369     VGA_DRAW_LINE15_LE,
1370     VGA_DRAW_LINE16_LE,
1371     VGA_DRAW_LINE24_LE,
1372     VGA_DRAW_LINE32_LE,
1373     VGA_DRAW_LINE15_BE,
1374     VGA_DRAW_LINE16_BE,
1375     VGA_DRAW_LINE24_BE,
1376     VGA_DRAW_LINE32_BE,
1377     VGA_DRAW_LINE_NB,
1378 };
1379 
1380 static vga_draw_line_func * const vga_draw_line_table[VGA_DRAW_LINE_NB] = {
1381     vga_draw_line2,
1382     vga_draw_line2d2,
1383     vga_draw_line4,
1384     vga_draw_line4d2,
1385     vga_draw_line8d2,
1386     vga_draw_line8,
1387     vga_draw_line15_le,
1388     vga_draw_line16_le,
1389     vga_draw_line24_le,
1390     vga_draw_line32_le,
1391     vga_draw_line15_be,
1392     vga_draw_line16_be,
1393     vga_draw_line24_be,
1394     vga_draw_line32_be,
1395 };
1396 
1397 static int vga_get_bpp(VGACommonState *s)
1398 {
1399     int ret;
1400 
1401     if (vbe_enabled(s)) {
1402         ret = s->vbe_regs[VBE_DISPI_INDEX_BPP];
1403     } else {
1404         ret = 0;
1405     }
1406     return ret;
1407 }
1408 
1409 static void vga_get_resolution(VGACommonState *s, int *pwidth, int *pheight)
1410 {
1411     int width, height;
1412 
1413     if (vbe_enabled(s)) {
1414         width = s->vbe_regs[VBE_DISPI_INDEX_XRES];
1415         height = s->vbe_regs[VBE_DISPI_INDEX_YRES];
1416     } else {
1417         width = (s->cr[VGA_CRTC_H_DISP] + 1) * 8;
1418         height = s->cr[VGA_CRTC_V_DISP_END] |
1419             ((s->cr[VGA_CRTC_OVERFLOW] & 0x02) << 7) |
1420             ((s->cr[VGA_CRTC_OVERFLOW] & 0x40) << 3);
1421         height = (height + 1);
1422     }
1423     *pwidth = width;
1424     *pheight = height;
1425 }
1426 
1427 void vga_invalidate_scanlines(VGACommonState *s, int y1, int y2)
1428 {
1429     int y;
1430     if (y1 >= VGA_MAX_HEIGHT)
1431         return;
1432     if (y2 >= VGA_MAX_HEIGHT)
1433         y2 = VGA_MAX_HEIGHT;
1434     for(y = y1; y < y2; y++) {
1435         s->invalidated_y_table[y >> 5] |= 1 << (y & 0x1f);
1436     }
1437 }
1438 
1439 static bool vga_scanline_invalidated(VGACommonState *s, int y)
1440 {
1441     if (y >= VGA_MAX_HEIGHT) {
1442         return false;
1443     }
1444     return s->invalidated_y_table[y >> 5] & (1 << (y & 0x1f));
1445 }
1446 
1447 void vga_dirty_log_start(VGACommonState *s)
1448 {
1449     memory_region_set_log(&s->vram, true, DIRTY_MEMORY_VGA);
1450 }
1451 
1452 void vga_dirty_log_stop(VGACommonState *s)
1453 {
1454     memory_region_set_log(&s->vram, false, DIRTY_MEMORY_VGA);
1455 }
1456 
1457 /*
1458  * graphic modes
1459  */
1460 static void vga_draw_graphic(VGACommonState *s, int full_update)
1461 {
1462     DisplaySurface *surface = qemu_console_surface(s->con);
1463     int y1, y, update, linesize, y_start, double_scan, mask, depth;
1464     int width, height, shift_control, bwidth, bits;
1465     ram_addr_t page0, page1, region_start, region_end;
1466     DirtyBitmapSnapshot *snap = NULL;
1467     int disp_width, multi_scan, multi_run;
1468     uint8_t *d;
1469     uint32_t v, addr1, addr;
1470     vga_draw_line_func *vga_draw_line = NULL;
1471     bool share_surface, force_shadow = false;
1472     pixman_format_code_t format;
1473 #ifdef HOST_WORDS_BIGENDIAN
1474     bool byteswap = !s->big_endian_fb;
1475 #else
1476     bool byteswap = s->big_endian_fb;
1477 #endif
1478 
1479     full_update |= update_basic_params(s);
1480 
1481     s->get_resolution(s, &width, &height);
1482     disp_width = width;
1483 
1484     region_start = (s->start_addr * 4);
1485     region_end = region_start + (ram_addr_t)s->line_offset * height;
1486     region_end += width * s->get_bpp(s) / 8; /* scanline length */
1487     region_end -= s->line_offset;
1488     if (region_end > s->vbe_size) {
1489         /* wraps around (can happen with cirrus vbe modes) */
1490         region_start = 0;
1491         region_end = s->vbe_size;
1492         force_shadow = true;
1493     }
1494 
1495     shift_control = (s->gr[VGA_GFX_MODE] >> 5) & 3;
1496     double_scan = (s->cr[VGA_CRTC_MAX_SCAN] >> 7);
1497     if (shift_control != 1) {
1498         multi_scan = (((s->cr[VGA_CRTC_MAX_SCAN] & 0x1f) + 1) << double_scan)
1499             - 1;
1500     } else {
1501         /* in CGA modes, multi_scan is ignored */
1502         /* XXX: is it correct ? */
1503         multi_scan = double_scan;
1504     }
1505     multi_run = multi_scan;
1506     if (shift_control != s->shift_control ||
1507         double_scan != s->double_scan) {
1508         full_update = 1;
1509         s->shift_control = shift_control;
1510         s->double_scan = double_scan;
1511     }
1512 
1513     if (shift_control == 0) {
1514         if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
1515             disp_width <<= 1;
1516         }
1517     } else if (shift_control == 1) {
1518         if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
1519             disp_width <<= 1;
1520         }
1521     }
1522 
1523     depth = s->get_bpp(s);
1524 
1525     /*
1526      * Check whether we can share the surface with the backend
1527      * or whether we need a shadow surface. We share native
1528      * endian surfaces for 15bpp and above and byteswapped
1529      * surfaces for 24bpp and above.
1530      */
1531     format = qemu_default_pixman_format(depth, !byteswap);
1532     if (format) {
1533         share_surface = dpy_gfx_check_format(s->con, format)
1534             && !s->force_shadow && !force_shadow;
1535     } else {
1536         share_surface = false;
1537     }
1538     if (s->line_offset != s->last_line_offset ||
1539         disp_width != s->last_width ||
1540         height != s->last_height ||
1541         s->last_depth != depth ||
1542         s->last_byteswap != byteswap ||
1543         share_surface != is_buffer_shared(surface)) {
1544         if (share_surface) {
1545             surface = qemu_create_displaysurface_from(disp_width,
1546                     height, format, s->line_offset,
1547                     s->vram_ptr + (s->start_addr * 4));
1548             dpy_gfx_replace_surface(s->con, surface);
1549         } else {
1550             qemu_console_resize(s->con, disp_width, height);
1551             surface = qemu_console_surface(s->con);
1552         }
1553         s->last_scr_width = disp_width;
1554         s->last_scr_height = height;
1555         s->last_width = disp_width;
1556         s->last_height = height;
1557         s->last_line_offset = s->line_offset;
1558         s->last_depth = depth;
1559         s->last_byteswap = byteswap;
1560         full_update = 1;
1561     } else if (is_buffer_shared(surface) &&
1562                (full_update || surface_data(surface) != s->vram_ptr
1563                 + (s->start_addr * 4))) {
1564         pixman_format_code_t format =
1565             qemu_default_pixman_format(depth, !byteswap);
1566         surface = qemu_create_displaysurface_from(disp_width,
1567                 height, format, s->line_offset,
1568                 s->vram_ptr + (s->start_addr * 4));
1569         dpy_gfx_replace_surface(s->con, surface);
1570     }
1571 
1572     if (shift_control == 0) {
1573         full_update |= update_palette16(s);
1574         if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
1575             v = VGA_DRAW_LINE4D2;
1576         } else {
1577             v = VGA_DRAW_LINE4;
1578         }
1579         bits = 4;
1580     } else if (shift_control == 1) {
1581         full_update |= update_palette16(s);
1582         if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
1583             v = VGA_DRAW_LINE2D2;
1584         } else {
1585             v = VGA_DRAW_LINE2;
1586         }
1587         bits = 4;
1588     } else {
1589         switch(s->get_bpp(s)) {
1590         default:
1591         case 0:
1592             full_update |= update_palette256(s);
1593             v = VGA_DRAW_LINE8D2;
1594             bits = 4;
1595             break;
1596         case 8:
1597             full_update |= update_palette256(s);
1598             v = VGA_DRAW_LINE8;
1599             bits = 8;
1600             break;
1601         case 15:
1602             v = s->big_endian_fb ? VGA_DRAW_LINE15_BE : VGA_DRAW_LINE15_LE;
1603             bits = 16;
1604             break;
1605         case 16:
1606             v = s->big_endian_fb ? VGA_DRAW_LINE16_BE : VGA_DRAW_LINE16_LE;
1607             bits = 16;
1608             break;
1609         case 24:
1610             v = s->big_endian_fb ? VGA_DRAW_LINE24_BE : VGA_DRAW_LINE24_LE;
1611             bits = 24;
1612             break;
1613         case 32:
1614             v = s->big_endian_fb ? VGA_DRAW_LINE32_BE : VGA_DRAW_LINE32_LE;
1615             bits = 32;
1616             break;
1617         }
1618     }
1619     vga_draw_line = vga_draw_line_table[v];
1620 
1621     if (!is_buffer_shared(surface) && s->cursor_invalidate) {
1622         s->cursor_invalidate(s);
1623     }
1624 
1625 #if 0
1626     printf("w=%d h=%d v=%d line_offset=%d cr[0x09]=0x%02x cr[0x17]=0x%02x linecmp=%d sr[0x01]=0x%02x\n",
1627            width, height, v, line_offset, s->cr[9], s->cr[VGA_CRTC_MODE],
1628            s->line_compare, sr(s, VGA_SEQ_CLOCK_MODE));
1629 #endif
1630     addr1 = (s->start_addr * 4);
1631     bwidth = DIV_ROUND_UP(width * bits, 8);
1632     y_start = -1;
1633     d = surface_data(surface);
1634     linesize = surface_stride(surface);
1635     y1 = 0;
1636 
1637     if (!full_update) {
1638         if (s->line_compare < height) {
1639             /* split screen mode */
1640             region_start = 0;
1641         }
1642         snap = memory_region_snapshot_and_clear_dirty(&s->vram, region_start,
1643                                                       region_end - region_start,
1644                                                       DIRTY_MEMORY_VGA);
1645     }
1646 
1647     for(y = 0; y < height; y++) {
1648         addr = addr1;
1649         if (!(s->cr[VGA_CRTC_MODE] & 1)) {
1650             int shift;
1651             /* CGA compatibility handling */
1652             shift = 14 + ((s->cr[VGA_CRTC_MODE] >> 6) & 1);
1653             addr = (addr & ~(1 << shift)) | ((y1 & 1) << shift);
1654         }
1655         if (!(s->cr[VGA_CRTC_MODE] & 2)) {
1656             addr = (addr & ~0x8000) | ((y1 & 2) << 14);
1657         }
1658         update = full_update;
1659         page0 = addr & s->vbe_size_mask;
1660         page1 = (addr + bwidth - 1) & s->vbe_size_mask;
1661         if (full_update) {
1662             update = 1;
1663         } else if (page1 < page0) {
1664             /* scanline wraps from end of video memory to the start */
1665             assert(force_shadow);
1666             update = memory_region_snapshot_get_dirty(&s->vram, snap,
1667                                                       page0, s->vbe_size - page0);
1668             update |= memory_region_snapshot_get_dirty(&s->vram, snap,
1669                                                        0, page1);
1670         } else {
1671             update = memory_region_snapshot_get_dirty(&s->vram, snap,
1672                                                       page0, page1 - page0);
1673         }
1674         /* explicit invalidation for the hardware cursor (cirrus only) */
1675         update |= vga_scanline_invalidated(s, y);
1676         if (update) {
1677             if (y_start < 0)
1678                 y_start = y;
1679             if (!(is_buffer_shared(surface))) {
1680                 vga_draw_line(s, d, addr, width);
1681                 if (s->cursor_draw_line)
1682                     s->cursor_draw_line(s, d, y);
1683             }
1684         } else {
1685             if (y_start >= 0) {
1686                 /* flush to display */
1687                 dpy_gfx_update(s->con, 0, y_start,
1688                                disp_width, y - y_start);
1689                 y_start = -1;
1690             }
1691         }
1692         if (!multi_run) {
1693             mask = (s->cr[VGA_CRTC_MODE] & 3) ^ 3;
1694             if ((y1 & mask) == mask)
1695                 addr1 += s->line_offset;
1696             y1++;
1697             multi_run = multi_scan;
1698         } else {
1699             multi_run--;
1700         }
1701         /* line compare acts on the displayed lines */
1702         if (y == s->line_compare)
1703             addr1 = 0;
1704         d += linesize;
1705     }
1706     if (y_start >= 0) {
1707         /* flush to display */
1708         dpy_gfx_update(s->con, 0, y_start,
1709                        disp_width, y - y_start);
1710     }
1711     g_free(snap);
1712     memset(s->invalidated_y_table, 0, sizeof(s->invalidated_y_table));
1713 }
1714 
1715 static void vga_draw_blank(VGACommonState *s, int full_update)
1716 {
1717     DisplaySurface *surface = qemu_console_surface(s->con);
1718     int i, w;
1719     uint8_t *d;
1720 
1721     if (!full_update)
1722         return;
1723     if (s->last_scr_width <= 0 || s->last_scr_height <= 0)
1724         return;
1725 
1726     w = s->last_scr_width * surface_bytes_per_pixel(surface);
1727     d = surface_data(surface);
1728     for(i = 0; i < s->last_scr_height; i++) {
1729         memset(d, 0, w);
1730         d += surface_stride(surface);
1731     }
1732     dpy_gfx_update(s->con, 0, 0,
1733                    s->last_scr_width, s->last_scr_height);
1734 }
1735 
1736 #define GMODE_TEXT     0
1737 #define GMODE_GRAPH    1
1738 #define GMODE_BLANK 2
1739 
1740 static void vga_update_display(void *opaque)
1741 {
1742     VGACommonState *s = opaque;
1743     DisplaySurface *surface = qemu_console_surface(s->con);
1744     int full_update, graphic_mode;
1745 
1746     qemu_flush_coalesced_mmio_buffer();
1747 
1748     if (surface_bits_per_pixel(surface) == 0) {
1749         /* nothing to do */
1750     } else {
1751         full_update = 0;
1752         if (!(s->ar_index & 0x20)) {
1753             graphic_mode = GMODE_BLANK;
1754         } else {
1755             graphic_mode = s->gr[VGA_GFX_MISC] & VGA_GR06_GRAPHICS_MODE;
1756         }
1757         if (graphic_mode != s->graphic_mode) {
1758             s->graphic_mode = graphic_mode;
1759             s->cursor_blink_time = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
1760             full_update = 1;
1761         }
1762         switch(graphic_mode) {
1763         case GMODE_TEXT:
1764             vga_draw_text(s, full_update);
1765             break;
1766         case GMODE_GRAPH:
1767             vga_draw_graphic(s, full_update);
1768             break;
1769         case GMODE_BLANK:
1770         default:
1771             vga_draw_blank(s, full_update);
1772             break;
1773         }
1774     }
1775 }
1776 
1777 /* force a full display refresh */
1778 static void vga_invalidate_display(void *opaque)
1779 {
1780     VGACommonState *s = opaque;
1781 
1782     s->last_width = -1;
1783     s->last_height = -1;
1784 }
1785 
1786 void vga_common_reset(VGACommonState *s)
1787 {
1788     s->sr_index = 0;
1789     memset(s->sr, '\0', sizeof(s->sr));
1790     memset(s->sr_vbe, '\0', sizeof(s->sr_vbe));
1791     s->gr_index = 0;
1792     memset(s->gr, '\0', sizeof(s->gr));
1793     s->ar_index = 0;
1794     memset(s->ar, '\0', sizeof(s->ar));
1795     s->ar_flip_flop = 0;
1796     s->cr_index = 0;
1797     memset(s->cr, '\0', sizeof(s->cr));
1798     s->msr = 0;
1799     s->fcr = 0;
1800     s->st00 = 0;
1801     s->st01 = 0;
1802     s->dac_state = 0;
1803     s->dac_sub_index = 0;
1804     s->dac_read_index = 0;
1805     s->dac_write_index = 0;
1806     memset(s->dac_cache, '\0', sizeof(s->dac_cache));
1807     s->dac_8bit = 0;
1808     memset(s->palette, '\0', sizeof(s->palette));
1809     s->bank_offset = 0;
1810     s->vbe_index = 0;
1811     memset(s->vbe_regs, '\0', sizeof(s->vbe_regs));
1812     s->vbe_regs[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;
1813     s->vbe_start_addr = 0;
1814     s->vbe_line_offset = 0;
1815     s->vbe_bank_mask = (s->vram_size >> 16) - 1;
1816     memset(s->font_offsets, '\0', sizeof(s->font_offsets));
1817     s->graphic_mode = -1; /* force full update */
1818     s->shift_control = 0;
1819     s->double_scan = 0;
1820     s->line_offset = 0;
1821     s->line_compare = 0;
1822     s->start_addr = 0;
1823     s->plane_updated = 0;
1824     s->last_cw = 0;
1825     s->last_ch = 0;
1826     s->last_width = 0;
1827     s->last_height = 0;
1828     s->last_scr_width = 0;
1829     s->last_scr_height = 0;
1830     s->cursor_start = 0;
1831     s->cursor_end = 0;
1832     s->cursor_offset = 0;
1833     s->big_endian_fb = s->default_endian_fb;
1834     memset(s->invalidated_y_table, '\0', sizeof(s->invalidated_y_table));
1835     memset(s->last_palette, '\0', sizeof(s->last_palette));
1836     memset(s->last_ch_attr, '\0', sizeof(s->last_ch_attr));
1837     switch (vga_retrace_method) {
1838     case VGA_RETRACE_DUMB:
1839         break;
1840     case VGA_RETRACE_PRECISE:
1841         memset(&s->retrace_info, 0, sizeof (s->retrace_info));
1842         break;
1843     }
1844     vga_update_memory_access(s);
1845 }
1846 
1847 static void vga_reset(void *opaque)
1848 {
1849     VGACommonState *s =  opaque;
1850     vga_common_reset(s);
1851 }
1852 
1853 #define TEXTMODE_X(x)	((x) % width)
1854 #define TEXTMODE_Y(x)	((x) / width)
1855 #define VMEM2CHTYPE(v)	((v & 0xff0007ff) | \
1856         ((v & 0x00000800) << 10) | ((v & 0x00007000) >> 1))
1857 /* relay text rendering to the display driver
1858  * instead of doing a full vga_update_display() */
1859 static void vga_update_text(void *opaque, console_ch_t *chardata)
1860 {
1861     VGACommonState *s =  opaque;
1862     int graphic_mode, i, cursor_offset, cursor_visible;
1863     int cw, cheight, width, height, size, c_min, c_max;
1864     uint32_t *src;
1865     console_ch_t *dst, val;
1866     char msg_buffer[80];
1867     int full_update = 0;
1868 
1869     qemu_flush_coalesced_mmio_buffer();
1870 
1871     if (!(s->ar_index & 0x20)) {
1872         graphic_mode = GMODE_BLANK;
1873     } else {
1874         graphic_mode = s->gr[VGA_GFX_MISC] & VGA_GR06_GRAPHICS_MODE;
1875     }
1876     if (graphic_mode != s->graphic_mode) {
1877         s->graphic_mode = graphic_mode;
1878         full_update = 1;
1879     }
1880     if (s->last_width == -1) {
1881         s->last_width = 0;
1882         full_update = 1;
1883     }
1884 
1885     switch (graphic_mode) {
1886     case GMODE_TEXT:
1887         /* TODO: update palette */
1888         full_update |= update_basic_params(s);
1889 
1890         /* total width & height */
1891         cheight = (s->cr[VGA_CRTC_MAX_SCAN] & 0x1f) + 1;
1892         cw = 8;
1893         if (!(sr(s, VGA_SEQ_CLOCK_MODE) & VGA_SR01_CHAR_CLK_8DOTS)) {
1894             cw = 9;
1895         }
1896         if (sr(s, VGA_SEQ_CLOCK_MODE) & 0x08) {
1897             cw = 16; /* NOTE: no 18 pixel wide */
1898         }
1899         width = (s->cr[VGA_CRTC_H_DISP] + 1);
1900         if (s->cr[VGA_CRTC_V_TOTAL] == 100) {
1901             /* ugly hack for CGA 160x100x16 - explain me the logic */
1902             height = 100;
1903         } else {
1904             height = s->cr[VGA_CRTC_V_DISP_END] |
1905                 ((s->cr[VGA_CRTC_OVERFLOW] & 0x02) << 7) |
1906                 ((s->cr[VGA_CRTC_OVERFLOW] & 0x40) << 3);
1907             height = (height + 1) / cheight;
1908         }
1909 
1910         size = (height * width);
1911         if (size > CH_ATTR_SIZE) {
1912             if (!full_update)
1913                 return;
1914 
1915             snprintf(msg_buffer, sizeof(msg_buffer), "%i x %i Text mode",
1916                      width, height);
1917             break;
1918         }
1919 
1920         if (width != s->last_width || height != s->last_height ||
1921             cw != s->last_cw || cheight != s->last_ch) {
1922             s->last_scr_width = width * cw;
1923             s->last_scr_height = height * cheight;
1924             qemu_console_resize(s->con, s->last_scr_width, s->last_scr_height);
1925             dpy_text_resize(s->con, width, height);
1926             s->last_depth = 0;
1927             s->last_width = width;
1928             s->last_height = height;
1929             s->last_ch = cheight;
1930             s->last_cw = cw;
1931             full_update = 1;
1932         }
1933 
1934         if (full_update) {
1935             s->full_update_gfx = 1;
1936         }
1937         if (s->full_update_text) {
1938             s->full_update_text = 0;
1939             full_update |= 1;
1940         }
1941 
1942         /* Update "hardware" cursor */
1943         cursor_offset = ((s->cr[VGA_CRTC_CURSOR_HI] << 8) |
1944                          s->cr[VGA_CRTC_CURSOR_LO]) - s->start_addr;
1945         if (cursor_offset != s->cursor_offset ||
1946             s->cr[VGA_CRTC_CURSOR_START] != s->cursor_start ||
1947             s->cr[VGA_CRTC_CURSOR_END] != s->cursor_end || full_update) {
1948             cursor_visible = !(s->cr[VGA_CRTC_CURSOR_START] & 0x20);
1949             if (cursor_visible && cursor_offset < size && cursor_offset >= 0)
1950                 dpy_text_cursor(s->con,
1951                                 TEXTMODE_X(cursor_offset),
1952                                 TEXTMODE_Y(cursor_offset));
1953             else
1954                 dpy_text_cursor(s->con, -1, -1);
1955             s->cursor_offset = cursor_offset;
1956             s->cursor_start = s->cr[VGA_CRTC_CURSOR_START];
1957             s->cursor_end = s->cr[VGA_CRTC_CURSOR_END];
1958         }
1959 
1960         src = (uint32_t *) s->vram_ptr + s->start_addr;
1961         dst = chardata;
1962 
1963         if (full_update) {
1964             for (i = 0; i < size; src ++, dst ++, i ++)
1965                 console_write_ch(dst, VMEM2CHTYPE(le32_to_cpu(*src)));
1966 
1967             dpy_text_update(s->con, 0, 0, width, height);
1968         } else {
1969             c_max = 0;
1970 
1971             for (i = 0; i < size; src ++, dst ++, i ++) {
1972                 console_write_ch(&val, VMEM2CHTYPE(le32_to_cpu(*src)));
1973                 if (*dst != val) {
1974                     *dst = val;
1975                     c_max = i;
1976                     break;
1977                 }
1978             }
1979             c_min = i;
1980             for (; i < size; src ++, dst ++, i ++) {
1981                 console_write_ch(&val, VMEM2CHTYPE(le32_to_cpu(*src)));
1982                 if (*dst != val) {
1983                     *dst = val;
1984                     c_max = i;
1985                 }
1986             }
1987 
1988             if (c_min <= c_max) {
1989                 i = TEXTMODE_Y(c_min);
1990                 dpy_text_update(s->con, 0, i, width, TEXTMODE_Y(c_max) - i + 1);
1991             }
1992         }
1993 
1994         return;
1995     case GMODE_GRAPH:
1996         if (!full_update)
1997             return;
1998 
1999         s->get_resolution(s, &width, &height);
2000         snprintf(msg_buffer, sizeof(msg_buffer), "%i x %i Graphic mode",
2001                  width, height);
2002         break;
2003     case GMODE_BLANK:
2004     default:
2005         if (!full_update)
2006             return;
2007 
2008         snprintf(msg_buffer, sizeof(msg_buffer), "VGA Blank mode");
2009         break;
2010     }
2011 
2012     /* Display a message */
2013     s->last_width = 60;
2014     s->last_height = height = 3;
2015     dpy_text_cursor(s->con, -1, -1);
2016     dpy_text_resize(s->con, s->last_width, height);
2017 
2018     for (dst = chardata, i = 0; i < s->last_width * height; i ++)
2019         console_write_ch(dst ++, ' ');
2020 
2021     size = strlen(msg_buffer);
2022     width = (s->last_width - size) / 2;
2023     dst = chardata + s->last_width + width;
2024     for (i = 0; i < size; i ++)
2025         console_write_ch(dst ++, ATTR2CHTYPE(msg_buffer[i], QEMU_COLOR_BLUE,
2026                                              QEMU_COLOR_BLACK, 1));
2027 
2028     dpy_text_update(s->con, 0, 0, s->last_width, height);
2029 }
2030 
2031 static uint64_t vga_mem_read(void *opaque, hwaddr addr,
2032                              unsigned size)
2033 {
2034     VGACommonState *s = opaque;
2035 
2036     return vga_mem_readb(s, addr);
2037 }
2038 
2039 static void vga_mem_write(void *opaque, hwaddr addr,
2040                           uint64_t data, unsigned size)
2041 {
2042     VGACommonState *s = opaque;
2043 
2044     vga_mem_writeb(s, addr, data);
2045 }
2046 
2047 const MemoryRegionOps vga_mem_ops = {
2048     .read = vga_mem_read,
2049     .write = vga_mem_write,
2050     .endianness = DEVICE_LITTLE_ENDIAN,
2051     .impl = {
2052         .min_access_size = 1,
2053         .max_access_size = 1,
2054     },
2055 };
2056 
2057 static int vga_common_post_load(void *opaque, int version_id)
2058 {
2059     VGACommonState *s = opaque;
2060 
2061     /* force refresh */
2062     s->graphic_mode = -1;
2063     vbe_update_vgaregs(s);
2064     vga_update_memory_access(s);
2065     return 0;
2066 }
2067 
2068 static bool vga_endian_state_needed(void *opaque)
2069 {
2070     VGACommonState *s = opaque;
2071 
2072     /*
2073      * Only send the endian state if it's different from the
2074      * default one, thus ensuring backward compatibility for
2075      * migration of the common case
2076      */
2077     return s->default_endian_fb != s->big_endian_fb;
2078 }
2079 
2080 static const VMStateDescription vmstate_vga_endian = {
2081     .name = "vga.endian",
2082     .version_id = 1,
2083     .minimum_version_id = 1,
2084     .needed = vga_endian_state_needed,
2085     .fields = (VMStateField[]) {
2086         VMSTATE_BOOL(big_endian_fb, VGACommonState),
2087         VMSTATE_END_OF_LIST()
2088     }
2089 };
2090 
2091 const VMStateDescription vmstate_vga_common = {
2092     .name = "vga",
2093     .version_id = 2,
2094     .minimum_version_id = 2,
2095     .post_load = vga_common_post_load,
2096     .fields = (VMStateField[]) {
2097         VMSTATE_UINT32(latch, VGACommonState),
2098         VMSTATE_UINT8(sr_index, VGACommonState),
2099         VMSTATE_PARTIAL_BUFFER(sr, VGACommonState, 8),
2100         VMSTATE_UINT8(gr_index, VGACommonState),
2101         VMSTATE_PARTIAL_BUFFER(gr, VGACommonState, 16),
2102         VMSTATE_UINT8(ar_index, VGACommonState),
2103         VMSTATE_BUFFER(ar, VGACommonState),
2104         VMSTATE_INT32(ar_flip_flop, VGACommonState),
2105         VMSTATE_UINT8(cr_index, VGACommonState),
2106         VMSTATE_BUFFER(cr, VGACommonState),
2107         VMSTATE_UINT8(msr, VGACommonState),
2108         VMSTATE_UINT8(fcr, VGACommonState),
2109         VMSTATE_UINT8(st00, VGACommonState),
2110         VMSTATE_UINT8(st01, VGACommonState),
2111 
2112         VMSTATE_UINT8(dac_state, VGACommonState),
2113         VMSTATE_UINT8(dac_sub_index, VGACommonState),
2114         VMSTATE_UINT8(dac_read_index, VGACommonState),
2115         VMSTATE_UINT8(dac_write_index, VGACommonState),
2116         VMSTATE_BUFFER(dac_cache, VGACommonState),
2117         VMSTATE_BUFFER(palette, VGACommonState),
2118 
2119         VMSTATE_INT32(bank_offset, VGACommonState),
2120         VMSTATE_UINT8_EQUAL(is_vbe_vmstate, VGACommonState, NULL),
2121         VMSTATE_UINT16(vbe_index, VGACommonState),
2122         VMSTATE_UINT16_ARRAY(vbe_regs, VGACommonState, VBE_DISPI_INDEX_NB),
2123         VMSTATE_UINT32(vbe_start_addr, VGACommonState),
2124         VMSTATE_UINT32(vbe_line_offset, VGACommonState),
2125         VMSTATE_UINT32(vbe_bank_mask, VGACommonState),
2126         VMSTATE_END_OF_LIST()
2127     },
2128     .subsections = (const VMStateDescription*[]) {
2129         &vmstate_vga_endian,
2130         NULL
2131     }
2132 };
2133 
2134 static const GraphicHwOps vga_ops = {
2135     .invalidate  = vga_invalidate_display,
2136     .gfx_update  = vga_update_display,
2137     .text_update = vga_update_text,
2138 };
2139 
2140 static inline uint32_t uint_clamp(uint32_t val, uint32_t vmin, uint32_t vmax)
2141 {
2142     if (val < vmin) {
2143         return vmin;
2144     }
2145     if (val > vmax) {
2146         return vmax;
2147     }
2148     return val;
2149 }
2150 
2151 void vga_common_init(VGACommonState *s, Object *obj, bool global_vmstate)
2152 {
2153     int i, j, v, b;
2154 
2155     for(i = 0;i < 256; i++) {
2156         v = 0;
2157         for(j = 0; j < 8; j++) {
2158             v |= ((i >> j) & 1) << (j * 4);
2159         }
2160         expand4[i] = v;
2161 
2162         v = 0;
2163         for(j = 0; j < 4; j++) {
2164             v |= ((i >> (2 * j)) & 3) << (j * 4);
2165         }
2166         expand2[i] = v;
2167     }
2168     for(i = 0; i < 16; i++) {
2169         v = 0;
2170         for(j = 0; j < 4; j++) {
2171             b = ((i >> j) & 1);
2172             v |= b << (2 * j);
2173             v |= b << (2 * j + 1);
2174         }
2175         expand4to8[i] = v;
2176     }
2177 
2178     s->vram_size_mb = uint_clamp(s->vram_size_mb, 1, 512);
2179     s->vram_size_mb = pow2ceil(s->vram_size_mb);
2180     s->vram_size = s->vram_size_mb << 20;
2181 
2182     if (!s->vbe_size) {
2183         s->vbe_size = s->vram_size;
2184     }
2185     s->vbe_size_mask = s->vbe_size - 1;
2186 
2187     s->is_vbe_vmstate = 1;
2188     memory_region_init_ram_nomigrate(&s->vram, obj, "vga.vram", s->vram_size,
2189                            &error_fatal);
2190     vmstate_register_ram(&s->vram, global_vmstate ? NULL : DEVICE(obj));
2191     xen_register_framebuffer(&s->vram);
2192     s->vram_ptr = memory_region_get_ram_ptr(&s->vram);
2193     s->get_bpp = vga_get_bpp;
2194     s->get_offsets = vga_get_offsets;
2195     s->get_resolution = vga_get_resolution;
2196     s->hw_ops = &vga_ops;
2197     switch (vga_retrace_method) {
2198     case VGA_RETRACE_DUMB:
2199         s->retrace = vga_dumb_retrace;
2200         s->update_retrace_info = vga_dumb_update_retrace_info;
2201         break;
2202 
2203     case VGA_RETRACE_PRECISE:
2204         s->retrace = vga_precise_retrace;
2205         s->update_retrace_info = vga_precise_update_retrace_info;
2206         break;
2207     }
2208 
2209     /*
2210      * Set default fb endian based on target, could probably be turned
2211      * into a device attribute set by the machine/platform to remove
2212      * all target endian dependencies from this file.
2213      */
2214 #ifdef TARGET_WORDS_BIGENDIAN
2215     s->default_endian_fb = true;
2216 #else
2217     s->default_endian_fb = false;
2218 #endif
2219     vga_dirty_log_start(s);
2220 }
2221 
2222 static const MemoryRegionPortio vga_portio_list[] = {
2223     { 0x04,  2, 1, .read = vga_ioport_read, .write = vga_ioport_write }, /* 3b4 */
2224     { 0x0a,  1, 1, .read = vga_ioport_read, .write = vga_ioport_write }, /* 3ba */
2225     { 0x10, 16, 1, .read = vga_ioport_read, .write = vga_ioport_write }, /* 3c0 */
2226     { 0x24,  2, 1, .read = vga_ioport_read, .write = vga_ioport_write }, /* 3d4 */
2227     { 0x2a,  1, 1, .read = vga_ioport_read, .write = vga_ioport_write }, /* 3da */
2228     PORTIO_END_OF_LIST(),
2229 };
2230 
2231 static const MemoryRegionPortio vbe_portio_list[] = {
2232     { 0, 1, 2, .read = vbe_ioport_read_index, .write = vbe_ioport_write_index },
2233 # ifdef TARGET_I386
2234     { 1, 1, 2, .read = vbe_ioport_read_data, .write = vbe_ioport_write_data },
2235 # endif
2236     { 2, 1, 2, .read = vbe_ioport_read_data, .write = vbe_ioport_write_data },
2237     PORTIO_END_OF_LIST(),
2238 };
2239 
2240 /* Used by both ISA and PCI */
2241 MemoryRegion *vga_init_io(VGACommonState *s, Object *obj,
2242                           const MemoryRegionPortio **vga_ports,
2243                           const MemoryRegionPortio **vbe_ports)
2244 {
2245     MemoryRegion *vga_mem;
2246 
2247     *vga_ports = vga_portio_list;
2248     *vbe_ports = vbe_portio_list;
2249 
2250     vga_mem = g_malloc(sizeof(*vga_mem));
2251     memory_region_init_io(vga_mem, obj, &vga_mem_ops, s,
2252                           "vga-lowmem", 0x20000);
2253     memory_region_set_flush_coalesced(vga_mem);
2254 
2255     return vga_mem;
2256 }
2257 
2258 void vga_init(VGACommonState *s, Object *obj, MemoryRegion *address_space,
2259               MemoryRegion *address_space_io, bool init_vga_ports)
2260 {
2261     MemoryRegion *vga_io_memory;
2262     const MemoryRegionPortio *vga_ports, *vbe_ports;
2263 
2264     qemu_register_reset(vga_reset, s);
2265 
2266     s->bank_offset = 0;
2267 
2268     s->legacy_address_space = address_space;
2269 
2270     vga_io_memory = vga_init_io(s, obj, &vga_ports, &vbe_ports);
2271     memory_region_add_subregion_overlap(address_space,
2272                                         0x000a0000,
2273                                         vga_io_memory,
2274                                         1);
2275     memory_region_set_coalescing(vga_io_memory);
2276     if (init_vga_ports) {
2277         portio_list_init(&s->vga_port_list, obj, vga_ports, s, "vga");
2278         portio_list_set_flush_coalesced(&s->vga_port_list);
2279         portio_list_add(&s->vga_port_list, address_space_io, 0x3b0);
2280     }
2281     if (vbe_ports) {
2282         portio_list_init(&s->vbe_port_list, obj, vbe_ports, s, "vbe");
2283         portio_list_add(&s->vbe_port_list, address_space_io, 0x1ce);
2284     }
2285 }
2286 
2287 void vga_init_vbe(VGACommonState *s, Object *obj, MemoryRegion *system_memory)
2288 {
2289     /* With pc-0.12 and below we map both the PCI BAR and the fixed VBE region,
2290      * so use an alias to avoid double-mapping the same region.
2291      */
2292     memory_region_init_alias(&s->vram_vbe, obj, "vram.vbe",
2293                              &s->vram, 0, memory_region_size(&s->vram));
2294     /* XXX: use optimized standard vga accesses */
2295     memory_region_add_subregion(system_memory,
2296                                 VBE_DISPI_LFB_PHYSICAL_ADDRESS,
2297                                 &s->vram_vbe);
2298     s->vbe_mapped = 1;
2299 }
2300