initial commit
[dos_imgv] / src / video.c
1 #include <stdlib.h>
2 #include <string.h>
3 #include <dos.h>
4 #include "cdpmi.h"
5 #include "video.h"
6 #include "vbe.h"
7 #include "vga.h"
8 #include "util.h"
9
10 #ifdef __WATCOMC__
11 #include <i86.h>
12 #define enable  _enable
13 #define disable _disable
14 #endif
15
16 #ifdef __DJGPP__
17 #define VMEM_PTR        ((void*)(0xa0000 + __djgpp_conventional_base))
18 #else
19 #define VMEM_PTR        ((void*)0xa0000)
20 #endif
21
22 #define SAME_BPP(a, b)  \
23         ((a) == (b) || ((a) == 16 && (b) == 15) || ((a) == 15 && (b) == 16) || \
24          ((a) == 32 && (b) == 24) || ((a) == 24 && (b) == 32))
25
26 void (*blit_frame)(void*, int);
27
28 int resizefb(int x, int y, int bpp, int pitch);
29
30 static void blit_frame_lfb(void *pixels, int vsync);
31 static void blit_frame_banked(void *pixels, int vsync);
32 static uint32_t calc_mask(int sz, int pos);
33
34 static void enable_wrcomb(uint32_t addr, int len);
35 static const char *mtrr_type_name(int type);
36 static void print_mtrr(void);
37
38 static struct video_mode *vmodes;
39 static int num_vmodes;
40
41 static int vbe_init_ver;
42 static struct vbe_info vbe;
43
44 /* current mode */
45 static struct video_mode *curmode;
46 static void *vpgaddr[2];
47 static int frontidx, backidx;
48 static int pgcount, pgsize, fbsize;
49
50
51 int init_video(void)
52 {
53         int i, num, max_modes;
54         struct video_mode *vmptr;
55
56         if(vbe_info(&vbe) == -1) {
57                 fprintf(stderr, "failed to retrieve VBE information\n");
58                 return -1;
59         }
60         vbe_print_info(stdout, &vbe);
61
62         num_vmodes = 0;
63         max_modes = 256;
64         if(!(vmodes = malloc(max_modes * sizeof *vmodes))) {
65                 fprintf(stderr, "failed to allocate video modes list\n");
66                 return -1;
67         }
68
69         num = vbe_num_modes(&vbe);
70         for(i=0; i<num; i++) {
71                 struct vbe_mode_info minf;
72
73                 if(vbe_mode_info(vbe.modes[i], &minf) == -1) {
74                         continue;
75                 }
76
77                 if(num_vmodes >= max_modes) {
78                         int newmax = max_modes ? (max_modes << 1) : 16;
79                         if(!(vmptr = realloc(vmodes, newmax * sizeof *vmodes))) {
80                                 fprintf(stderr, "failed to grow video mode list (%d)\n", newmax);
81                                 free(vmodes);
82                                 return -1;
83                         }
84                         vmodes = vmptr;
85                         max_modes = newmax;
86                 }
87
88                 vmptr = vmodes + num_vmodes++;
89                 memset(vmptr, 0, sizeof *vmptr);
90                 vmptr->mode = vbe.modes[i];
91                 vmptr->xsz = minf.xres;
92                 vmptr->ysz = minf.yres;
93                 vmptr->bpp = minf.bpp;
94                 vmptr->pitch = minf.scanline_bytes;
95                 if(minf.mem_model == VBE_TYPE_DIRECT) {
96                         vmptr->rbits = minf.rsize;
97                         vmptr->gbits = minf.gsize;
98                         vmptr->bbits = minf.bsize;
99                         vmptr->rshift = minf.rpos;
100                         vmptr->gshift = minf.gpos;
101                         vmptr->bshift = minf.bpos;
102                         vmptr->rmask = calc_mask(minf.rsize, minf.rpos);
103                         vmptr->gmask = calc_mask(minf.gsize, minf.gpos);
104                         vmptr->bmask = calc_mask(minf.bsize, minf.bpos);
105                         /*vmptr->bpp = vmptr->rbits + vmptr->gbits + vmptr->bbits;*/
106                 }
107 #ifndef DBG_NOLFB
108                 if(minf.attr & VBE_ATTR_LFB) {
109                         vmptr->fb_addr = minf.fb_addr;
110                 }
111 #endif
112                 vmptr->max_pages = minf.num_img_pages;
113                 vmptr->win_gran = minf.win_gran;
114
115                 printf("%04x: ", vbe.modes[i]);
116                 vbe_print_mode_info(stdout, &minf);
117         }
118         fflush(stdout);
119
120         vbe_init_ver = VBE_VER_MAJOR(vbe.ver);
121         return 0;
122 }
123
124 void cleanup_video(void)
125 {
126         free(vmodes);
127 }
128
129 struct video_mode *video_modes(void)
130 {
131         return vmodes;
132 }
133
134 int num_video_modes(void)
135 {
136         return num_vmodes;
137 }
138
139 struct video_mode *get_video_mode(int idx)
140 {
141         if(idx == VMODE_CURRENT) {
142                 return curmode;
143         }
144         return vmodes + idx;
145 }
146
147 int match_video_mode(int xsz, int ysz, int bpp)
148 {
149         int i, best = -1;
150         struct video_mode *vm;
151
152         for(i=0; i<num_vmodes; i++) {
153                 vm = vmodes + i;
154                 if(vm->xsz != xsz || vm->ysz != ysz) continue;
155                 if(SAME_BPP(vm->bpp, bpp)) {
156                         best = i;
157                 }
158                 if(vm->bpp == bpp) break;
159         }
160
161         if(best == -1) {
162                 fprintf(stderr, "failed to find video mode %dx%d %d bpp)\n", xsz, ysz, bpp);
163                 return -1;
164         }
165         return best;
166 }
167
168 int find_video_mode(int mode)
169 {
170         int i;
171         struct video_mode *vm;
172
173         vm = vmodes;
174         for(i=0; i<num_vmodes; i++) {
175                 if(vm->mode == mode) return i;
176                 vm++;
177         }
178         return -1;
179 }
180
181 void *set_video_mode(int idx, int nbuf)
182 {
183         unsigned int mode;
184         struct video_mode *vm = vmodes + idx;
185         struct cpuid_info cpu;
186
187         if(curmode == vm) return vpgaddr[0];
188
189         printf("setting video mode %x (%dx%d %d bpp)\n", (unsigned int)vm->mode,
190                         vm->xsz, vm->ysz, vm->bpp);
191         fflush(stdout);
192
193 #ifndef DBG_NOLFB
194         mode = vm->mode | VBE_MODE_LFB;
195         if(vbe_setmode(mode) == -1) {
196 #endif
197                 mode = vm->mode;
198                 if(vbe_setmode(mode) == -1) {
199                         fprintf(stderr, "failed to set video mode %x\n", (unsigned int)vm->mode);
200                         return 0;
201                 }
202                 printf("Warning: failed to get a linear framebuffer. falling back to banked mode\n");
203 #ifndef DBG_NOLFB
204         }
205 #endif
206
207         /* unmap previous video memory mapping, if there was one (switching modes) */
208         if(vpgaddr[0] && vpgaddr[0] != VMEM_PTR) {
209                 dpmi_munmap(vpgaddr[0]);
210                 vpgaddr[0] = vpgaddr[1] = 0;
211         }
212
213         curmode = vm;
214         if(nbuf < 1) nbuf = 1;
215         if(nbuf > 2) nbuf = 2;
216         pgcount = nbuf > vm->max_pages + 1 ? vm->max_pages + 1 : nbuf;
217         pgsize = vm->ysz * vm->pitch;
218         fbsize = pgcount * pgsize;
219
220         if(vm->bpp > 8) {
221                 printf("rgb mask: %x %x %x\n", (unsigned int)vm->rmask,
222                                 (unsigned int)vm->gmask, (unsigned int)vm->bmask);
223                 printf("rgb shift: %d %d %d\n", vm->rshift, vm->gshift, vm->bshift);
224         }
225         printf("pgcount: %d, pgsize: %d, fbsize: %d\n", pgcount, pgsize, fbsize);
226         if(vm->fb_addr) {
227                 printf("phys addr: %p\n", (void*)vm->fb_addr);
228         }
229         fflush(stdout);
230
231         if(vm->fb_addr) {
232                 vpgaddr[0] = (void*)dpmi_mmap(vm->fb_addr, fbsize);
233                 if(!vpgaddr[0]) {
234                         fprintf(stderr, "failed to map framebuffer (phys: %lx, size: %d)\n",
235                                         (unsigned long)vm->fb_addr, fbsize);
236                         set_text_mode();
237                         return 0;
238                 }
239                 memset(vpgaddr[0], 0xaa, pgsize);
240
241                 if(pgcount > 1) {
242                         vpgaddr[1] = (char*)vpgaddr[0] + pgsize;
243                         backidx = 1;
244                         page_flip(FLIP_NOW);    /* start with the second page visible */
245                 } else {
246                         frontidx = backidx = 0;
247                         vpgaddr[1] = 0;
248                 }
249
250                 blit_frame = blit_frame_lfb;
251
252 #ifdef ENABLE_WRCOMB
253                 if(read_cpuid(&cpu) != -1 && cpu.feat & CPUID_FEAT_MTRR) {
254                         uint32_t len = (uint32_t)vbe.vmem_blk << 16;
255
256                         /* if vmem_blk is 0 or if the reported size is absurd (more than
257                          * 256mb), just use the framebuffer size for this mode to setup the
258                          * mtrr
259                          */
260                         if(!len || len > 0x10000000) {
261                                 printf("reported vmem too large or overflowed, using fbsize for wrcomb setup\n");
262                                 len = fbsize;
263                         }
264                         print_mtrr();
265                         enable_wrcomb(vm->fb_addr, len);
266                 }
267 #endif
268
269         } else {
270                 vpgaddr[0] = VMEM_PTR;
271                 if(pgcount > 1) {
272                         vpgaddr[1] = VMEM_PTR;
273                         backidx = 1;
274                         page_flip(FLIP_NOW);    /* start with the second page visible */
275                 } else {
276                         frontidx = backidx = 0;
277                         vpgaddr[1] = 0;
278                 }
279
280                 blit_frame = blit_frame_banked;
281
282                 /* calculate window granularity shift */
283                 vm->win_gran_shift = 0;
284                 vm->win_64k_step = 1;
285                 if(vm->win_gran > 0 && vm->win_gran < 64) {
286                         int gran = vm->win_gran;
287                         while(gran < 64) {
288                                 vm->win_gran_shift++;
289                                 gran <<= 1;
290                         }
291                         vm->win_64k_step = 1 << vm->win_gran_shift;
292                 }
293
294                 printf("granularity: %dk (step: %d)\n", vm->win_gran, vm->win_64k_step);
295         }
296
297         fflush(stdout);
298         return vpgaddr[0];
299 }
300
301 int set_text_mode(void)
302 {
303         /* unmap previous video memory mapping, if there was one (switching modes) */
304         if(vpgaddr[0] && vpgaddr[0] != VMEM_PTR) {
305                 dpmi_munmap(vpgaddr[0]);
306                 vpgaddr[0] = vpgaddr[1] = 0;
307         }
308
309         vga_setmode(3);
310         curmode = 0;
311         return 0;
312 }
313
314 void *page_flip(int vsync)
315 {
316         if(!vpgaddr[1]) {
317                 /* page flipping not supported */
318                 return vpgaddr[0];
319         }
320
321         vbe_swap(backidx ? pgsize : 0, vsync ? VBE_SWAP_VBLANK : VBE_SWAP_NOW);
322         frontidx = backidx;
323         backidx = (backidx + 1) & 1;
324
325         return vpgaddr[backidx];
326 }
327
328
329 static void blit_frame_lfb(void *pixels, int vsync)
330 {
331         if(vsync) wait_vsync();
332         memcpy64(vpgaddr[frontidx], pixels, pgsize >> 3);
333 }
334
335 static void blit_frame_banked(void *pixels, int vsync)
336 {
337         int sz, offs, pending;
338         unsigned char *pptr = pixels;
339
340         if(vsync) wait_vsync();
341
342         /* assume initial window offset at 0 */
343         offs = 0;
344         pending = pgsize;
345         while(pending > 0) {
346                 sz = pending > 65536 ? 65536 : pending;
347                 /*memcpy64(VMEM_PTR, pptr, sz >> 3);*/
348                 memcpy(VMEM_PTR, pptr, sz);
349                 pptr += sz;
350                 pending -= sz;
351                 offs += curmode->win_64k_step;
352                 vbe_setwin(0, offs);
353         }
354         vbe_setwin(0, 0);
355 }
356
357 static uint32_t calc_mask(int sz, int pos)
358 {
359         uint32_t mask = 0;
360         while(sz-- > 0) {
361                 mask = (mask << 1) | 1;
362         }
363         return mask << pos;
364 }
365
366 #ifdef __GNUC__
367 #define get_msr(msr, low, high) \
368         asm volatile( \
369                 "\r\trdmsr" \
370                 : "=a"(low), "=d"(high) \
371                 : "c"(msr))
372
373 #define set_msr(msr, low, high) \
374         asm volatile( \
375                 "\r\twrmsr" \
376                 :: "c"(msr), "a"(low), "d"(high))
377
378 #endif  /* __GNUC__ */
379
380 #ifdef __WATCOMC__
381 #define get_msr(msr, low, high) get_msr_asm(msr, &low, &high)
382
383 void get_msr_asm(uint32_t msr, uint32_t *lowptr, uint32_t *highptr);
384 #pragma aux get_msr_asm = \
385         "rdmsr" \
386         "mov [ebx], eax" \
387         "mov [esi], edx" \
388         parm [ecx][ebx][esi] \
389         modify [eax]
390
391 void set_msr(uint32_t msr, uint32_t low, uint32_t high);
392 #pragma aux set_msr = \
393         "wrmsr" \
394         parm [ecx][eax][edx]
395
396 #endif  /* __WATCOMC__ */
397         
398
399 #define MSR_MTRRCAP                     0xfe
400 #define MSR_MTRRDEFTYPE         0x2ff
401 #define MSR_MTRRBASE(x)         (0x200 | ((x) << 1))
402 #define MSR_MTRRMASK(x)         (0x201 | ((x) << 1))
403 #define MTRRDEF_EN                      0x800
404 #define MTRRCAP_HAVE_WC         0x400
405 #define MTRRMASK_VALID          0x800
406
407 #define MTRR_WC                         1
408
409 static int get_page_memtype(uint32_t addr, int num_ranges)
410 {
411         int i;
412         uint32_t rlow, rhigh;
413         uint32_t base, mask;
414
415         for(i=0; i<num_ranges; i++) {
416                 get_msr(MSR_MTRRMASK(i), rlow, rhigh);
417                 if(!(rlow & MTRRMASK_VALID)) {
418                         continue;
419                 }
420                 mask = rlow & 0xfffff000;
421
422                 get_msr(MSR_MTRRBASE(i), rlow, rhigh);
423                 base = rlow & 0xfffff000;
424
425                 if((addr & mask) == (base & mask)) {
426                         return rlow & 0xff;
427                 }
428         }
429
430         get_msr(MSR_MTRRDEFTYPE, rlow, rhigh);
431         return rlow & 0xff;
432 }
433
434 static int check_wrcomb_enabled(uint32_t addr, int len, int num_ranges)
435 {
436         while(len > 0) {
437                 if(get_page_memtype(addr, num_ranges) != MTRR_WC) {
438                         return 0;
439                 }
440                 addr += 4096;
441                 len -= 4096;
442         }
443         return 1;
444 }
445
446 static int alloc_mtrr(int num_ranges)
447 {
448         int i;
449         uint32_t rlow, rhigh;
450
451         for(i=0; i<num_ranges; i++) {
452                 get_msr(MSR_MTRRMASK(i), rlow, rhigh);
453                 if(!(rlow & MTRRMASK_VALID)) {
454                         return i;
455                 }
456         }
457         return -1;
458 }
459
460 static void enable_wrcomb(uint32_t addr, int len)
461 {
462         int num_ranges, mtrr;
463         uint32_t rlow, rhigh;
464         uint32_t def, mask;
465
466         if(len <= 0 || (addr | (uint32_t)len) & 0xfff) {
467                 fprintf(stderr, "failed to enable write combining, unaligned range: %p/%x\n",
468                                 (void*)addr, (unsigned int)len);
469                 return;
470         }
471
472         get_msr(MSR_MTRRCAP, rlow, rhigh);
473         num_ranges = rlow & 0xff;
474
475         printf("enable_wrcomb: addr=%p len=%x\n", (void*)addr, (unsigned int)len);
476
477         if(!(rlow & MTRRCAP_HAVE_WC)) {
478                 fprintf(stderr, "failed to enable write combining, processor doesn't support it\n");
479                 return;
480         }
481
482         if(check_wrcomb_enabled(addr, len, num_ranges)) {
483                 return;
484         }
485
486         if((mtrr = alloc_mtrr(num_ranges)) == -1) {
487                 fprintf(stderr, "failed to enable write combining, no free MTRRs\n");
488                 return;
489         }
490
491         mask = len - 1;
492         mask |= mask >> 1;
493         mask |= mask >> 2;
494         mask |= mask >> 4;
495         mask |= mask >> 8;
496         mask |= mask >> 16;
497         mask = ~mask & 0xfffff000;
498
499         printf("  ... mask: %08x\n", (unsigned int)mask);
500
501         disable();
502         get_msr(MSR_MTRRDEFTYPE, def, rhigh);
503         set_msr(MSR_MTRRDEFTYPE, def & ~MTRRDEF_EN, rhigh);
504
505         set_msr(MSR_MTRRBASE(mtrr), addr | MTRR_WC, 0);
506         set_msr(MSR_MTRRMASK(mtrr), mask | MTRRMASK_VALID, 0);
507
508         set_msr(MSR_MTRRDEFTYPE, def | MTRRDEF_EN, 0);
509         enable();
510 }
511
512 static const char *mtrr_names[] = { "N/A", "W C", "N/A", "N/A", "W T", "W P", "W B" };
513
514 static const char *mtrr_type_name(int type)
515 {
516         if(type < 0 || type >= sizeof mtrr_names / sizeof *mtrr_names) {
517                 return mtrr_names[0];
518         }
519         return mtrr_names[type];
520 }
521
522 static void print_mtrr(void)
523 {
524         int i, num_ranges;
525         uint32_t rlow, rhigh, base, mask;
526
527         get_msr(MSR_MTRRCAP, rlow, rhigh);
528         num_ranges = rlow & 0xff;
529
530         for(i=0; i<num_ranges; i++) {
531                 get_msr(MSR_MTRRBASE(i), base, rhigh);
532                 get_msr(MSR_MTRRMASK(i), mask, rhigh);
533
534                 if(mask & MTRRMASK_VALID) {
535                         printf("mtrr%d: base %p, mask %08x type %s\n", i, (void*)(base & 0xfffff000),
536                                         (unsigned int)(mask & 0xfffff000), mtrr_type_name(base & 0xff));
537                 } else {
538                         printf("mtrr%d unused (%08x/%08x)\n", i, (unsigned int)base,
539                                         (unsigned int)mask);
540                 }
541         }
542         fflush(stdout);
543 }