1 /* -*- linux-c -*- ------------------------------------------------------- * 2 * 3 * Copyright (C) 1991, 1992 Linus Torvalds 4 * Copyright 2007 rPath, Inc. - All Rights Reserved 5 * 6 * This file is part of the Linux kernel, and is made available under 7 * the terms of the GNU General Public License version 2. 8 * 9 * ----------------------------------------------------------------------- */ 10 11 /* 12 * arch/i386/boot/video-vesa.c 13 * 14 * VESA text modes 15 */ 16 17 #include "boot.h" 18 #include "video.h" 19 #include "vesa.h" 20 21 /* VESA information */ 22 static struct vesa_general_info vginfo; 23 static struct vesa_mode_info vminfo; 24 25 __videocard video_vesa; 26 27 static void vesa_store_mode_params_graphics(void); 28 29 static int vesa_probe(void) 30 { 31 #if defined(CONFIG_VIDEO_VESA) || defined(CONFIG_FIRMWARE_EDID) 32 u16 ax, cx, di; 33 u16 mode; 34 addr_t mode_ptr; 35 struct mode_info *mi; 36 int nmodes = 0; 37 38 video_vesa.modes = GET_HEAP(struct mode_info, 0); 39 40 vginfo.signature = VBE2_MAGIC; 41 42 ax = 0x4f00; 43 di = (size_t)&vginfo; 44 asm(INT10 45 : "+a" (ax), "+D" (di), "=m" (vginfo) 46 : : "ebx", "ecx", "edx", "esi"); 47 48 if (ax != 0x004f || 49 vginfo.signature != VESA_MAGIC || 50 vginfo.version < 0x0102) 51 return 0; /* Not present */ 52 #endif /* CONFIG_VIDEO_VESA || CONFIG_FIRMWARE_EDID */ 53 #ifdef CONFIG_VIDEO_VESA 54 set_fs(vginfo.video_mode_ptr.seg); 55 mode_ptr = vginfo.video_mode_ptr.off; 56 57 while ((mode = rdfs16(mode_ptr)) != 0xffff) { 58 mode_ptr += 2; 59 60 if (!heap_free(sizeof(struct mode_info))) 61 break; /* Heap full, can't save mode info */ 62 63 if (mode & ~0x1ff) 64 continue; 65 66 memset(&vminfo, 0, sizeof vminfo); /* Just in case... */ 67 68 ax = 0x4f01; 69 cx = mode; 70 di = (size_t)&vminfo; 71 asm(INT10 72 : "+a" (ax), "+c" (cx), "+D" (di), "=m" (vminfo) 73 : : "ebx", "edx", "esi"); 74 75 if (ax != 0x004f) 76 continue; 77 78 if ((vminfo.mode_attr & 0x15) == 0x05) { 79 /* Text Mode, TTY BIOS supported, 80 supported by hardware */ 81 mi = GET_HEAP(struct mode_info, 1); 82 mi->mode = mode + VIDEO_FIRST_VESA; 83 mi->depth = 0; /* text */ 84 mi->x = vminfo.h_res; 85 mi->y = vminfo.v_res; 86 nmodes++; 87 } else if ((vminfo.mode_attr & 0x99) == 0x99 && 88 (vminfo.memory_layout == 4 || 89 vminfo.memory_layout == 6) && 90 vminfo.memory_planes == 1) { 91 #ifdef CONFIG_FB 92 /* Graphics mode, color, linear frame buffer 93 supported. Only register the mode if 94 if framebuffer is configured, however, 95 otherwise the user will be left without a screen. 96 We don't require CONFIG_FB_VESA, however, since 97 some of the other framebuffer drivers can use 98 this mode-setting, too. */ 99 mi = GET_HEAP(struct mode_info, 1); 100 mi->mode = mode + VIDEO_FIRST_VESA; 101 mi->depth = vminfo.bpp; 102 mi->x = vminfo.h_res; 103 mi->y = vminfo.v_res; 104 nmodes++; 105 #endif 106 } 107 } 108 109 return nmodes; 110 #else 111 return 0; 112 #endif /* CONFIG_VIDEO_VESA */ 113 } 114 115 static int vesa_set_mode(struct mode_info *mode) 116 { 117 u16 ax, bx, cx, di; 118 int is_graphic; 119 u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA; 120 121 memset(&vminfo, 0, sizeof vminfo); /* Just in case... */ 122 123 ax = 0x4f01; 124 cx = vesa_mode; 125 di = (size_t)&vminfo; 126 asm(INT10 127 : "+a" (ax), "+c" (cx), "+D" (di), "=m" (vminfo) 128 : : "ebx", "edx", "esi"); 129 130 if (ax != 0x004f) 131 return -1; 132 133 if ((vminfo.mode_attr & 0x15) == 0x05) { 134 /* It's a supported text mode */ 135 is_graphic = 0; 136 } else if ((vminfo.mode_attr & 0x99) == 0x99) { 137 /* It's a graphics mode with linear frame buffer */ 138 is_graphic = 1; 139 vesa_mode |= 0x4000; /* Request linear frame buffer */ 140 } else { 141 return -1; /* Invalid mode */ 142 } 143 144 145 ax = 0x4f02; 146 bx = vesa_mode; 147 di = 0; 148 asm volatile(INT10 149 : "+a" (ax), "+b" (bx), "+D" (di) 150 : : "ecx", "edx", "esi"); 151 152 if (ax != 0x004f) 153 return -1; 154 155 graphic_mode = is_graphic; 156 if (!is_graphic) { 157 /* Text mode */ 158 force_x = mode->x; 159 force_y = mode->y; 160 do_restore = 1; 161 } else { 162 /* Graphics mode */ 163 vesa_store_mode_params_graphics(); 164 } 165 166 return 0; 167 } 168 169 170 /* Switch DAC to 8-bit mode */ 171 static void vesa_dac_set_8bits(void) 172 { 173 u8 dac_size = 6; 174 175 /* If possible, switch the DAC to 8-bit mode */ 176 if (vginfo.capabilities & 1) { 177 u16 ax, bx; 178 179 ax = 0x4f08; 180 bx = 0x0800; 181 asm volatile(INT10 182 : "+a" (ax), "+b" (bx) 183 : : "ecx", "edx", "esi", "edi"); 184 185 if (ax == 0x004f) 186 dac_size = bx >> 8; 187 } 188 189 /* Set the color sizes to the DAC size, and offsets to 0 */ 190 boot_params.screen_info.red_size = dac_size; 191 boot_params.screen_info.green_size = dac_size; 192 boot_params.screen_info.blue_size = dac_size; 193 boot_params.screen_info.rsvd_size = dac_size; 194 195 boot_params.screen_info.red_pos = 0; 196 boot_params.screen_info.green_pos = 0; 197 boot_params.screen_info.blue_pos = 0; 198 boot_params.screen_info.rsvd_pos = 0; 199 } 200 201 /* Save the VESA protected mode info */ 202 static void vesa_store_pm_info(void) 203 { 204 u16 ax, bx, di, es; 205 206 ax = 0x4f0a; 207 bx = di = 0; 208 asm("pushw %%es; "INT10"; movw %%es,%0; popw %%es" 209 : "=d" (es), "+a" (ax), "+b" (bx), "+D" (di) 210 : : "ecx", "esi"); 211 212 if (ax != 0x004f) 213 return; 214 215 boot_params.screen_info.vesapm_seg = es; 216 boot_params.screen_info.vesapm_off = di; 217 } 218 219 /* 220 * Save video mode parameters for graphics mode 221 */ 222 static void vesa_store_mode_params_graphics(void) 223 { 224 /* Tell the kernel we're in VESA graphics mode */ 225 boot_params.screen_info.orig_video_isVGA = 0x23; 226 227 /* Mode parameters */ 228 boot_params.screen_info.vesa_attributes = vminfo.mode_attr; 229 boot_params.screen_info.lfb_linelength = vminfo.logical_scan; 230 boot_params.screen_info.lfb_width = vminfo.h_res; 231 boot_params.screen_info.lfb_height = vminfo.v_res; 232 boot_params.screen_info.lfb_depth = vminfo.bpp; 233 boot_params.screen_info.pages = vminfo.image_planes; 234 boot_params.screen_info.lfb_base = vminfo.lfb_ptr; 235 memcpy(&boot_params.screen_info.red_size, 236 &vminfo.rmask, 8); 237 238 /* General parameters */ 239 boot_params.screen_info.lfb_size = vginfo.total_memory; 240 241 if (vminfo.bpp <= 8) 242 vesa_dac_set_8bits(); 243 244 vesa_store_pm_info(); 245 } 246 247 /* 248 * Save EDID information for the kernel; this is invoked, separately, 249 * after mode-setting. 250 */ 251 void vesa_store_edid(void) 252 { 253 #ifdef CONFIG_FIRMWARE_EDID 254 u16 ax, bx, cx, dx, di; 255 256 /* Apparently used as a nonsense token... */ 257 memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info); 258 259 if (vginfo.version < 0x0200) 260 return; /* EDID requires VBE 2.0+ */ 261 262 ax = 0x4f15; /* VBE DDC */ 263 bx = 0x0000; /* Report DDC capabilities */ 264 cx = 0; /* Controller 0 */ 265 di = 0; /* ES:DI must be 0 by spec */ 266 267 /* Note: The VBE DDC spec is different from the main VESA spec; 268 we genuinely have to assume all registers are destroyed here. */ 269 270 asm("pushw %%es; movw %2,%%es; "INT10"; popw %%es" 271 : "+a" (ax), "+b" (bx) 272 : "c" (cx), "D" (di) 273 : "esi"); 274 275 if (ax != 0x004f) 276 return; /* No EDID */ 277 278 /* BH = time in seconds to transfer EDD information */ 279 /* BL = DDC level supported */ 280 281 ax = 0x4f15; /* VBE DDC */ 282 bx = 0x0001; /* Read EDID */ 283 cx = 0; /* Controller 0 */ 284 dx = 0; /* EDID block number */ 285 di =(size_t) &boot_params.edid_info; /* (ES:)Pointer to block */ 286 asm(INT10 287 : "+a" (ax), "+b" (bx), "+d" (dx), "=m" (boot_params.edid_info) 288 : "c" (cx), "D" (di) 289 : "esi"); 290 #endif /* CONFIG_FIRMWARE_EDID */ 291 } 292 293 __videocard video_vesa = 294 { 295 .card_name = "VESA", 296 .probe = vesa_probe, 297 .set_mode = vesa_set_mode, 298 .xmode_first = VIDEO_FIRST_VESA, 299 .xmode_n = 0x200, 300 }; 301