+ unsigned int mode;
+ struct video_mode *vm = vmodes + idx;
+
+ if(curmode == vm) return vpgaddr[0];
+
+ printf("setting video mode %x (%dx%d %d bpp)\n", (unsigned int)vm->mode,
+ vm->xsz, vm->ysz, vm->bpp);
+ fflush(stdout);
+
+ mode = vm->mode | VBE_MODE_LFB;
+ if(vbe_setmode(mode) == -1) {
+ mode = vm->mode;
+ if(vbe_setmode(mode) == -1) {
+ fprintf(stderr, "failed to set video mode %x\n", (unsigned int)vm->mode);
+ return 0;
+ }
+ printf("Warning: failed to get a linear framebuffer. falling back to banked mode\n");
+ }
+
+ /* unmap previous video memory mapping, if there was one (switching modes) */
+ if(vpgaddr[0] && vpgaddr[0] != (void*)0xa0000) {
+ dpmi_munmap(vpgaddr[0]);
+ vpgaddr[0] = vpgaddr[1] = 0;
+ }
+
+ curmode = vm;
+ if(nbuf < 1) nbuf = 1;
+ if(nbuf > 2) nbuf = 2;
+ pgcount = nbuf > vm->max_pages ? vm->max_pages : nbuf;
+ pgsize = vm->ysz * vm->pitch;
+ fbsize = pgcount * pgsize;
+
+ printf("pgcount: %d, pgsize: %d, fbsize: %d\n", pgcount, pgsize, fbsize);
+ printf("phys addr: %p\n", (void*)vm->fb_addr);
+ fflush(stdout);
+
+ if(vm->fb_addr) {
+ vpgaddr[0] = (void*)dpmi_mmap(vm->fb_addr, fbsize);
+ if(!vpgaddr[0]) {
+ fprintf(stderr, "failed to map framebuffer (phys: %lx, size: %d)\n",
+ (unsigned long)vm->fb_addr, fbsize);
+ set_text_mode();
+ return 0;
+ }
+ memset(vpgaddr[0], 0xaa, pgsize);
+
+ if(pgcount > 1) {
+ vpgaddr[1] = (char*)vpgaddr[0] + pgsize;
+ backidx = 1;
+ page_flip(FLIP_NOW); /* start with the second page visible */
+ } else {
+ frontidx = backidx = 0;
+ vpgaddr[1] = 0;
+ }
+
+ blit_frame = blit_frame_lfb;
+
+ } else {
+ vpgaddr[0] = (void*)0xa0000;
+ vpgaddr[1] = 0;
+
+ blit_frame = blit_frame_banked;
+ }
+
+ /* allocate main memory framebuffer */
+ if(demo_resizefb(vm->xsz, vm->ysz, vm->bpp) == -1) {
+ fprintf(stderr, "failed to allocate %dx%d (%d bpp) framebuffer\n", vm->xsz,
+ vm->ysz, vm->bpp);
+ set_text_mode();
+ return 0;