1 /* -*- linux-c -*- ------------------------------------------------------- * 2 * 3 * Copyright (C) 1991, 1992 Linus Torvalds 4 * Copyright 2007 rPath, Inc. - All Rights Reserved 5 * Copyright 2009 Intel Corporation; author H. Peter Anvin 6 * 7 * This file is part of the Linux kernel, and is made available under 8 * the terms of the GNU General Public License version 2. 9 * 10 * ----------------------------------------------------------------------- */ 11 12 /* 13 * Common all-VGA modes 14 */ 15 16 #include "boot.h" 17 #include "video.h" 18 19 static struct mode_info vga_modes[] = { 20 { VIDEO_80x25, 80, 25, 0 }, 21 { VIDEO_8POINT, 80, 50, 0 }, 22 { VIDEO_80x43, 80, 43, 0 }, 23 { VIDEO_80x28, 80, 28, 0 }, 24 { VIDEO_80x30, 80, 30, 0 }, 25 { VIDEO_80x34, 80, 34, 0 }, 26 { VIDEO_80x60, 80, 60, 0 }, 27 }; 28 29 static struct mode_info ega_modes[] = { 30 { VIDEO_80x25, 80, 25, 0 }, 31 { VIDEO_8POINT, 80, 43, 0 }, 32 }; 33 34 static struct mode_info cga_modes[] = { 35 { VIDEO_80x25, 80, 25, 0 }, 36 }; 37 38 static __videocard video_vga; 39 40 /* Set basic 80x25 mode */ 41 static u8 vga_set_basic_mode(void) 42 { 43 struct biosregs ireg, oreg; 44 u16 ax; 45 u8 rows; 46 u8 mode; 47 48 initregs(&ireg); 49 50 #ifdef CONFIG_VIDEO_400_HACK 51 if (adapter >= ADAPTER_VGA) { 52 ireg.ax = 0x1202; 53 ireg.bx = 0x0030; 54 intcall(0x10, &ireg, NULL); 55 } 56 #endif 57 58 ax = 0x0f00; 59 intcall(0x10, &ireg, &oreg); 60 mode = oreg.al; 61 62 set_fs(0); 63 rows = rdfs8(0x484); /* rows minus one */ 64 65 #ifndef CONFIG_VIDEO_400_HACK 66 if ((oreg.ax == 0x5003 || oreg.ax == 0x5007) && 67 (rows == 0 || rows == 24)) 68 return mode; 69 #endif 70 71 if (mode != 3 && mode != 7) 72 mode = 3; 73 74 /* Set the mode */ 75 ireg.ax = mode; /* AH=0: set mode */ 76 intcall(0x10, &ireg, NULL); 77 do_restore = 1; 78 return mode; 79 } 80 81 static void vga_set_8font(void) 82 { 83 /* Set 8x8 font - 80x43 on EGA, 80x50 on VGA */ 84 struct biosregs ireg; 85 86 initregs(&ireg); 87 88 /* Set 8x8 font */ 89 ireg.ax = 0x1112; 90 /* ireg.bl = 0; */ 91 intcall(0x10, &ireg, NULL); 92 93 /* Use alternate print screen */ 94 ireg.ax = 0x1200; 95 ireg.bl = 0x20; 96 intcall(0x10, &ireg, NULL); 97 98 /* Turn off cursor emulation */ 99 ireg.ax = 0x1201; 100 ireg.bl = 0x34; 101 intcall(0x10, &ireg, NULL); 102 103 /* Cursor is scan lines 6-7 */ 104 ireg.ax = 0x0100; 105 ireg.cx = 0x0607; 106 intcall(0x10, &ireg, NULL); 107 } 108 109 static void vga_set_14font(void) 110 { 111 /* Set 9x14 font - 80x28 on VGA */ 112 struct biosregs ireg; 113 114 initregs(&ireg); 115 116 /* Set 9x14 font */ 117 ireg.ax = 0x1111; 118 /* ireg.bl = 0; */ 119 intcall(0x10, &ireg, NULL); 120 121 /* Turn off cursor emulation */ 122 ireg.ax = 0x1201; 123 ireg.bl = 0x34; 124 intcall(0x10, &ireg, NULL); 125 126 /* Cursor is scan lines 11-12 */ 127 ireg.ax = 0x0100; 128 ireg.cx = 0x0b0c; 129 intcall(0x10, &ireg, NULL); 130 } 131 132 static void vga_set_80x43(void) 133 { 134 /* Set 80x43 mode on VGA (not EGA) */ 135 struct biosregs ireg; 136 137 initregs(&ireg); 138 139 /* Set 350 scans */ 140 ireg.ax = 0x1201; 141 ireg.bl = 0x30; 142 intcall(0x10, &ireg, NULL); 143 144 /* Reset video mode */ 145 ireg.ax = 0x0003; 146 intcall(0x10, &ireg, NULL); 147 148 vga_set_8font(); 149 } 150 151 /* I/O address of the VGA CRTC */ 152 u16 vga_crtc(void) 153 { 154 return (inb(0x3cc) & 1) ? 0x3d4 : 0x3b4; 155 } 156 157 static void vga_set_480_scanlines(void) 158 { 159 u16 crtc; /* CRTC base address */ 160 u8 csel; /* CRTC miscellaneous output register */ 161 162 crtc = vga_crtc(); 163 164 out_idx(0x0c, crtc, 0x11); /* Vertical sync end, unlock CR0-7 */ 165 out_idx(0x0b, crtc, 0x06); /* Vertical total */ 166 out_idx(0x3e, crtc, 0x07); /* Vertical overflow */ 167 out_idx(0xea, crtc, 0x10); /* Vertical sync start */ 168 out_idx(0xdf, crtc, 0x12); /* Vertical display end */ 169 out_idx(0xe7, crtc, 0x15); /* Vertical blank start */ 170 out_idx(0x04, crtc, 0x16); /* Vertical blank end */ 171 csel = inb(0x3cc); 172 csel &= 0x0d; 173 csel |= 0xe2; 174 outb(csel, 0x3c2); 175 } 176 177 static void vga_set_vertical_end(int lines) 178 { 179 u16 crtc; /* CRTC base address */ 180 u8 ovfw; /* CRTC overflow register */ 181 int end = lines-1; 182 183 crtc = vga_crtc(); 184 185 ovfw = 0x3c | ((end >> (8-1)) & 0x02) | ((end >> (9-6)) & 0x40); 186 187 out_idx(ovfw, crtc, 0x07); /* Vertical overflow */ 188 out_idx(end, crtc, 0x12); /* Vertical display end */ 189 } 190 191 static void vga_set_80x30(void) 192 { 193 vga_set_480_scanlines(); 194 vga_set_vertical_end(30*16); 195 } 196 197 static void vga_set_80x34(void) 198 { 199 vga_set_480_scanlines(); 200 vga_set_14font(); 201 vga_set_vertical_end(34*14); 202 } 203 204 static void vga_set_80x60(void) 205 { 206 vga_set_480_scanlines(); 207 vga_set_8font(); 208 vga_set_vertical_end(60*8); 209 } 210 211 static int vga_set_mode(struct mode_info *mode) 212 { 213 /* Set the basic mode */ 214 vga_set_basic_mode(); 215 216 /* Override a possibly broken BIOS */ 217 force_x = mode->x; 218 force_y = mode->y; 219 220 switch (mode->mode) { 221 case VIDEO_80x25: 222 break; 223 case VIDEO_8POINT: 224 vga_set_8font(); 225 break; 226 case VIDEO_80x43: 227 vga_set_80x43(); 228 break; 229 case VIDEO_80x28: 230 vga_set_14font(); 231 break; 232 case VIDEO_80x30: 233 vga_set_80x30(); 234 break; 235 case VIDEO_80x34: 236 vga_set_80x34(); 237 break; 238 case VIDEO_80x60: 239 vga_set_80x60(); 240 break; 241 } 242 243 return 0; 244 } 245 246 /* 247 * Note: this probe includes basic information required by all 248 * systems. It should be executed first, by making sure 249 * video-vga.c is listed first in the Makefile. 250 */ 251 static int vga_probe(void) 252 { 253 static const char *card_name[] = { 254 "CGA/MDA/HGC", "EGA", "VGA" 255 }; 256 static struct mode_info *mode_lists[] = { 257 cga_modes, 258 ega_modes, 259 vga_modes, 260 }; 261 static int mode_count[] = { 262 sizeof(cga_modes)/sizeof(struct mode_info), 263 sizeof(ega_modes)/sizeof(struct mode_info), 264 sizeof(vga_modes)/sizeof(struct mode_info), 265 }; 266 267 struct biosregs ireg, oreg; 268 269 initregs(&ireg); 270 271 ireg.ax = 0x1200; 272 ireg.bl = 0x10; /* Check EGA/VGA */ 273 intcall(0x10, &ireg, &oreg); 274 275 #ifndef _WAKEUP 276 boot_params.screen_info.orig_video_ega_bx = oreg.bx; 277 #endif 278 279 /* If we have MDA/CGA/HGC then BL will be unchanged at 0x10 */ 280 if (oreg.bl != 0x10) { 281 /* EGA/VGA */ 282 ireg.ax = 0x1a00; 283 intcall(0x10, &ireg, &oreg); 284 285 if (oreg.al == 0x1a) { 286 adapter = ADAPTER_VGA; 287 #ifndef _WAKEUP 288 boot_params.screen_info.orig_video_isVGA = 1; 289 #endif 290 } else { 291 adapter = ADAPTER_EGA; 292 } 293 } else { 294 adapter = ADAPTER_CGA; 295 } 296 297 video_vga.modes = mode_lists[adapter]; 298 video_vga.card_name = card_name[adapter]; 299 return mode_count[adapter]; 300 } 301 302 static __videocard video_vga = { 303 .card_name = "VGA", 304 .probe = vga_probe, 305 .set_mode = vga_set_mode, 306 }; 307