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 * Select video mode 14 */ 15 16 #include "boot.h" 17 #include "video.h" 18 #include "vesa.h" 19 20 static void store_cursor_position(void) 21 { 22 struct biosregs ireg, oreg; 23 24 initregs(&ireg); 25 ireg.ah = 0x03; 26 intcall(0x10, &ireg, &oreg); 27 28 boot_params.screen_info.orig_x = oreg.dl; 29 boot_params.screen_info.orig_y = oreg.dh; 30 } 31 32 static void store_video_mode(void) 33 { 34 struct biosregs ireg, oreg; 35 36 /* N.B.: the saving of the video page here is a bit silly, 37 since we pretty much assume page 0 everywhere. */ 38 initregs(&ireg); 39 ireg.ah = 0x0f; 40 intcall(0x10, &ireg, &oreg); 41 42 /* Not all BIOSes are clean with respect to the top bit */ 43 boot_params.screen_info.orig_video_mode = oreg.al & 0x7f; 44 boot_params.screen_info.orig_video_page = oreg.bh; 45 } 46 47 /* 48 * Store the video mode parameters for later usage by the kernel. 49 * This is done by asking the BIOS except for the rows/columns 50 * parameters in the default 80x25 mode -- these are set directly, 51 * because some very obscure BIOSes supply insane values. 52 */ 53 static void store_mode_params(void) 54 { 55 u16 font_size; 56 int x, y; 57 58 /* For graphics mode, it is up to the mode-setting driver 59 (currently only video-vesa.c) to store the parameters */ 60 if (graphic_mode) 61 return; 62 63 store_cursor_position(); 64 store_video_mode(); 65 66 if (boot_params.screen_info.orig_video_mode == 0x07) { 67 /* MDA, HGC, or VGA in monochrome mode */ 68 video_segment = 0xb000; 69 } else { 70 /* CGA, EGA, VGA and so forth */ 71 video_segment = 0xb800; 72 } 73 74 set_fs(0); 75 font_size = rdfs16(0x485); /* Font size, BIOS area */ 76 boot_params.screen_info.orig_video_points = font_size; 77 78 x = rdfs16(0x44a); 79 y = (adapter == ADAPTER_CGA) ? 25 : rdfs8(0x484)+1; 80 81 if (force_x) 82 x = force_x; 83 if (force_y) 84 y = force_y; 85 86 boot_params.screen_info.orig_video_cols = x; 87 boot_params.screen_info.orig_video_lines = y; 88 } 89 90 static unsigned int get_entry(void) 91 { 92 char entry_buf[4]; 93 int i, len = 0; 94 int key; 95 unsigned int v; 96 97 do { 98 key = getchar(); 99 100 if (key == '\b') { 101 if (len > 0) { 102 puts("\b \b"); 103 len--; 104 } 105 } else if ((key >= '0' && key <= '9') || 106 (key >= 'A' && key <= 'Z') || 107 (key >= 'a' && key <= 'z')) { 108 if (len < sizeof entry_buf) { 109 entry_buf[len++] = key; 110 putchar(key); 111 } 112 } 113 } while (key != '\r'); 114 putchar('\n'); 115 116 if (len == 0) 117 return VIDEO_CURRENT_MODE; /* Default */ 118 119 v = 0; 120 for (i = 0; i < len; i++) { 121 v <<= 4; 122 key = entry_buf[i] | 0x20; 123 v += (key > '9') ? key-'a'+10 : key-'0'; 124 } 125 126 return v; 127 } 128 129 static void display_menu(void) 130 { 131 struct card_info *card; 132 struct mode_info *mi; 133 char ch; 134 int i; 135 int nmodes; 136 int modes_per_line; 137 int col; 138 139 nmodes = 0; 140 for (card = video_cards; card < video_cards_end; card++) 141 nmodes += card->nmodes; 142 143 modes_per_line = 1; 144 if (nmodes >= 20) 145 modes_per_line = 3; 146 147 for (col = 0; col < modes_per_line; col++) 148 puts("Mode: Resolution: Type: "); 149 putchar('\n'); 150 151 col = 0; 152 ch = '0'; 153 for (card = video_cards; card < video_cards_end; card++) { 154 mi = card->modes; 155 for (i = 0; i < card->nmodes; i++, mi++) { 156 char resbuf[32]; 157 int visible = mi->x && mi->y; 158 u16 mode_id = mi->mode ? mi->mode : 159 (mi->y << 8)+mi->x; 160 161 if (!visible) 162 continue; /* Hidden mode */ 163 164 if (mi->depth) 165 sprintf(resbuf, "%dx%d", mi->y, mi->depth); 166 else 167 sprintf(resbuf, "%d", mi->y); 168 169 printf("%c %03X %4dx%-7s %-6s", 170 ch, mode_id, mi->x, resbuf, card->card_name); 171 col++; 172 if (col >= modes_per_line) { 173 putchar('\n'); 174 col = 0; 175 } 176 177 if (ch == '9') 178 ch = 'a'; 179 else if (ch == 'z' || ch == ' ') 180 ch = ' '; /* Out of keys... */ 181 else 182 ch++; 183 } 184 } 185 if (col) 186 putchar('\n'); 187 } 188 189 #define H(x) ((x)-'a'+10) 190 #define SCAN ((H('s')<<12)+(H('c')<<8)+(H('a')<<4)+H('n')) 191 192 static unsigned int mode_menu(void) 193 { 194 int key; 195 unsigned int sel; 196 197 puts("Press <ENTER> to see video modes available, " 198 "<SPACE> to continue, or wait 30 sec\n"); 199 200 kbd_flush(); 201 while (1) { 202 key = getchar_timeout(); 203 if (key == ' ' || key == 0) 204 return VIDEO_CURRENT_MODE; /* Default */ 205 if (key == '\r') 206 break; 207 putchar('\a'); /* Beep! */ 208 } 209 210 211 for (;;) { 212 display_menu(); 213 214 puts("Enter a video mode or \"scan\" to scan for " 215 "additional modes: "); 216 sel = get_entry(); 217 if (sel != SCAN) 218 return sel; 219 220 probe_cards(1); 221 } 222 } 223 224 #ifdef CONFIG_VIDEO_RETAIN 225 /* Save screen content to the heap */ 226 static struct saved_screen { 227 int x, y; 228 int curx, cury; 229 u16 *data; 230 } saved; 231 232 static void save_screen(void) 233 { 234 /* Should be called after store_mode_params() */ 235 saved.x = boot_params.screen_info.orig_video_cols; 236 saved.y = boot_params.screen_info.orig_video_lines; 237 saved.curx = boot_params.screen_info.orig_x; 238 saved.cury = boot_params.screen_info.orig_y; 239 240 if (!heap_free(saved.x*saved.y*sizeof(u16)+512)) 241 return; /* Not enough heap to save the screen */ 242 243 saved.data = GET_HEAP(u16, saved.x*saved.y); 244 245 set_fs(video_segment); 246 copy_from_fs(saved.data, 0, saved.x*saved.y*sizeof(u16)); 247 } 248 249 static void restore_screen(void) 250 { 251 /* Should be called after store_mode_params() */ 252 int xs = boot_params.screen_info.orig_video_cols; 253 int ys = boot_params.screen_info.orig_video_lines; 254 int y; 255 addr_t dst = 0; 256 u16 *src = saved.data; 257 struct biosregs ireg; 258 259 if (graphic_mode) 260 return; /* Can't restore onto a graphic mode */ 261 262 if (!src) 263 return; /* No saved screen contents */ 264 265 /* Restore screen contents */ 266 267 set_fs(video_segment); 268 for (y = 0; y < ys; y++) { 269 int npad; 270 271 if (y < saved.y) { 272 int copy = (xs < saved.x) ? xs : saved.x; 273 copy_to_fs(dst, src, copy*sizeof(u16)); 274 dst += copy*sizeof(u16); 275 src += saved.x; 276 npad = (xs < saved.x) ? 0 : xs-saved.x; 277 } else { 278 npad = xs; 279 } 280 281 /* Writes "npad" blank characters to 282 video_segment:dst and advances dst */ 283 asm volatile("pushw %%es ; " 284 "movw %2,%%es ; " 285 "shrw %%cx ; " 286 "jnc 1f ; " 287 "stosw \n\t" 288 "1: rep;stosl ; " 289 "popw %%es" 290 : "+D" (dst), "+c" (npad) 291 : "bdS" (video_segment), 292 "a" (0x07200720)); 293 } 294 295 /* Restore cursor position */ 296 initregs(&ireg); 297 ireg.ah = 0x02; /* Set cursor position */ 298 ireg.dh = saved.cury; 299 ireg.dl = saved.curx; 300 intcall(0x10, &ireg, NULL); 301 } 302 #else 303 #define save_screen() ((void)0) 304 #define restore_screen() ((void)0) 305 #endif 306 307 void set_video(void) 308 { 309 u16 mode = boot_params.hdr.vid_mode; 310 311 RESET_HEAP(); 312 313 store_mode_params(); 314 save_screen(); 315 probe_cards(0); 316 317 for (;;) { 318 if (mode == ASK_VGA) 319 mode = mode_menu(); 320 321 if (!set_mode(mode)) 322 break; 323 324 printf("Undefined video mode number: %x\n", mode); 325 mode = ASK_VGA; 326 } 327 boot_params.hdr.vid_mode = mode; 328 vesa_store_edid(); 329 store_mode_params(); 330 331 if (do_restore) 332 restore_screen(); 333 } 334