src/mesa/drivers/dos/vga.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  4.1
   4  *
   5  * Copyright (C) 1999  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /*
  26  * DOS/DJGPP device driver v1.7 for Mesa
  27  *
  28  *  Copyright (C) 2002 - Borca Daniel
  29  *  Email : dborca@users.sourceforge.net
  30  *  Web   : http://www.geocities.com/dborca
  31  */
  32
  33
  34 #include <pc.h>
  35 #include <stdlib.h>
  36
  37 #include "video.h"
  38 #include "vga.h"
  39
  40
  41 static vl_mode modes[] = {
  42    {
  43     /* .xres    = */ 320,
  44     /* .yres    = */ 200,
  45     /* .bpp     = */ 8,
  46     /* .mode    = */ 0x13 | 0x4000,
  47     /* .scanlen = */ 320,
  48     /* .sel     = */ -1,
  49     /* .gran    = */ 320*200
  50    },
  51    {
  52     /* .xres    = */ -1,
  53     /* .yres    = */ -1,
  54     /* .bpp     = */ -1,
  55     /* .mode    = */ 0xffff,
  56     /* .scanlen = */ -1,
  57     /* .sel     = */ -1,
  58     /* .gran    = */ -1
  59    }
  60 };
  61
  62 static word16 vga_ver;
  63 static int linear_selector;
  64 static int oldmode = -1;
  65
  66 #define vga_color_precision 6
  67
  68
  69 /* Desc: Attempts to detect VGA, check video modes and create selectors.
  70  *
  71  * In  : -
  72  * Out : mode array
  73  *
  74  * Note: -
  75  */
  76 static vl_mode *
  77 vga_init (void)
  78 {
  79    int rv = 0;
  80
  81    if (vga_ver) {
  82       return modes;
  83    }
  84
  85    __asm("\n\
  86                 movw    $0x1a00, %%ax   \n\
  87                 int     $0x10           \n\
  88                 cmpb    $0x1a, %%al     \n\
  89                 jne     0f              \n\
  90                 cmpb    $0x07, %%bl     \n\
  91                 jb      0f              \n\
  92                 andl    $0xff, %%ebx    \n\
  93                 movl    %%ebx, %0       \n\
  94    0:":"=g"(rv)::"%eax", "%ebx");
  95    if (rv == 0) {
  96       return NULL;
  97    }
  98
  99    if (_create_selector(&linear_selector, 0xa0000, 0x10000)) {
 100       return NULL;
 101    }
 102
 103    modes[0].sel = linear_selector;
 104
 105    vga_ver = rv;
 106    return modes;
 107 }
 108
 109
 110 /* Desc: Frees all resources allocated by VGA init code.
 111  *
 112  * In  : -
 113  * Out : -
 114  *
 115  * Note: -
 116  */
 117 static void
 118 vga_fini (void)
 119 {
 120    if (vga_ver) {
 121       _remove_selector(&linear_selector);
 122    }
 123 }
 124
 125
 126 /* Desc: Attempts to enter specified video mode.
 127  *
 128  * In  : ptr to mode structure, refresh rate
 129  * Out : 0 if success
 130  *
 131  * Note: -
 132  */
 133 static int
 134 vga_entermode (vl_mode *p, int refresh)
 135 {
 136    if (!(p->mode & 0x4000)) {
 137       return -1;
 138    }
 139    VGA.blit = _can_mmx() ? vesa_l_dump_virtual_mmx : vesa_l_dump_virtual;
 140
 141    if (oldmode == -1) {
 142       __asm("\n\
 143                 movb    $0x0f, %%ah     \n\
 144                 int     $0x10           \n\
 145                 andl    $0xff, %%eax    \n\
 146                 movl    %%eax, %0       \n\
 147       ":"=g"(oldmode)::"%eax", "%ebx");
 148    }
 149
 150    __asm("int $0x10"::"a"(p->mode&0xff));
 151
 152    return 0;
 153
 154    (void)refresh; /* silence compiler warning */
 155 }
 156
 157
 158 /* Desc: Restores to the mode prior to first call to vga_entermode.
 159  *
 160  * In  : -
 161  * Out : -
 162  *
 163  * Note: -
 164  */
 165 static void
 166 vga_restore (void)
 167 {
 168    if (oldmode != -1) {
 169       __asm("int $0x10"::"a"(oldmode));
 170       oldmode = -1;
 171    }
 172 }
 173
 174
 175 /* Desc: set one palette entry
 176  *
 177  * In  : color index, R, G, B
 178  * Out : -
 179  *
 180  * Note: uses integer values
 181  */
 182 static void
 183 vga_setCI_i (int index, int red, int green, int blue)
 184 {
 185 #if 0
 186    __asm("\n\
 187                 movw    $0x1010, %%ax   \n\
 188                 movb    %1, %%dh        \n\
 189                 movb    %2, %%ch        \n\
 190                 int     $0x10           \n\
 191    "::"b"(index), "m"(red), "m"(green), "c"(blue):"%eax", "%edx");
 192 #else
 193    outportb(0x03C8, index);
 194    outportb(0x03C9, red);
 195    outportb(0x03C9, green);
 196    outportb(0x03C9, blue);
 197 #endif
 198 }
 199
 200
 201 /* Desc: set one palette entry
 202  *
 203  * In  : color index, R, G, B
 204  * Out : -
 205  *
 206  * Note: uses normalized values
 207  */
 208 static void
 209 vga_setCI_f (int index, float red, float green, float blue)
 210 {
 211     float max = (1 << vga_color_precision) - 1;
 212
 213     vga_setCI_i(index, (int)(red * max), (int)(green * max), (int)(blue * max));
 214 }
 215
 216
 217 /* Desc: state retrieval
 218  *
 219  * In  : parameter name, ptr to storage
 220  * Out : 0 if request successfully processed
 221  *
 222  * Note: -
 223  */
 224 static int
 225 vga_get (int pname, int *params)
 226 {
 227    switch (pname) {
 228       case VL_GET_CI_PREC:
 229          params[0] = vga_color_precision;
 230          break;
 231       default:
 232          return -1;
 233    }
 234    return 0;
 235 }
 236
 237
 238 /*
 239  * the driver
 240  */
 241 vl_driver VGA = {
 242    vga_init,
 243    vga_entermode,
 244    NULL,
 245    vga_setCI_f,
 246    vga_setCI_i,
 247    vga_get,
 248    vga_restore,
 249    vga_fini
 250 };