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->x = vminfo.h_res; 84 mi->y = vminfo.v_res; 85 nmodes++; 86 } else if ((vminfo.mode_attr & 0x99) == 0x99) { 87 #ifdef CONFIG_FB 88 /* Graphics mode, color, linear frame buffer 89 supported -- register the mode but hide from 90 the menu. Only do this if framebuffer is 91 configured, however, otherwise the user will 92 be left without a screen. */ 93 mi = GET_HEAP(struct mode_info, 1); 94 mi->mode = mode + VIDEO_FIRST_VESA; 95 mi->x = mi->y = 0; 96 nmodes++; 97 #endif 98 } 99 } 100 101 return nmodes; 102 #else 103 return 0; 104 #endif /* CONFIG_VIDEO_VESA */ 105 } 106 107 static int vesa_set_mode(struct mode_info *mode) 108 { 109 u16 ax, bx, cx, di; 110 int is_graphic; 111 u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA; 112 113 memset(&vminfo, 0, sizeof vminfo); /* Just in case... */ 114 115 ax = 0x4f01; 116 cx = vesa_mode; 117 di = (size_t)&vminfo; 118 asm(INT10 119 : "+a" (ax), "+c" (cx), "+D" (di), "=m" (vminfo) 120 : : "ebx", "edx", "esi"); 121 122 if (ax != 0x004f) 123 return -1; 124 125 if ((vminfo.mode_attr & 0x15) == 0x05) { 126 /* It's a supported text mode */ 127 is_graphic = 0; 128 } else if ((vminfo.mode_attr & 0x99) == 0x99) { 129 /* It's a graphics mode with linear frame buffer */ 130 is_graphic = 1; 131 vesa_mode |= 0x4000; /* Request linear frame buffer */ 132 } else { 133 return -1; /* Invalid mode */ 134 } 135 136 137 ax = 0x4f02; 138 bx = vesa_mode; 139 di = 0; 140 asm volatile(INT10 141 : "+a" (ax), "+b" (bx), "+D" (di) 142 : : "ecx", "edx", "esi"); 143 144 if (ax != 0x004f) 145 return -1; 146 147 graphic_mode = is_graphic; 148 if (!is_graphic) { 149 /* Text mode */ 150 force_x = mode->x; 151 force_y = mode->y; 152 do_restore = 1; 153 } else { 154 /* Graphics mode */ 155 vesa_store_mode_params_graphics(); 156 } 157 158 return 0; 159 } 160 161 162 /* Switch DAC to 8-bit mode */ 163 static void vesa_dac_set_8bits(void) 164 { 165 u8 dac_size = 6; 166 167 /* If possible, switch the DAC to 8-bit mode */ 168 if (vginfo.capabilities & 1) { 169 u16 ax, bx; 170 171 ax = 0x4f08; 172 bx = 0x0800; 173 asm volatile(INT10 174 : "+a" (ax), "+b" (bx) 175 : : "ecx", "edx", "esi", "edi"); 176 177 if (ax == 0x004f) 178 dac_size = bx >> 8; 179 } 180 181 /* Set the color sizes to the DAC size, and offsets to 0 */ 182 boot_params.screen_info.red_size = dac_size; 183 boot_params.screen_info.green_size = dac_size; 184 boot_params.screen_info.blue_size = dac_size; 185 boot_params.screen_info.rsvd_size = dac_size; 186 187 boot_params.screen_info.red_pos = 0; 188 boot_params.screen_info.green_pos = 0; 189 boot_params.screen_info.blue_pos = 0; 190 boot_params.screen_info.rsvd_pos = 0; 191 } 192 193 /* Save the VESA protected mode info */ 194 static void vesa_store_pm_info(void) 195 { 196 u16 ax, bx, di, es; 197 198 ax = 0x4f0a; 199 bx = di = 0; 200 asm("pushw %%es; "INT10"; movw %%es,%0; popw %%es" 201 : "=d" (es), "+a" (ax), "+b" (bx), "+D" (di) 202 : : "ecx", "esi"); 203 204 if (ax != 0x004f) 205 return; 206 207 boot_params.screen_info.vesapm_seg = es; 208 boot_params.screen_info.vesapm_off = di; 209 } 210 211 /* 212 * Save video mode parameters for graphics mode 213 */ 214 static void vesa_store_mode_params_graphics(void) 215 { 216 /* Tell the kernel we're in VESA graphics mode */ 217 boot_params.screen_info.orig_video_isVGA = 0x23; 218 219 /* Mode parameters */ 220 boot_params.screen_info.vesa_attributes = vminfo.mode_attr; 221 boot_params.screen_info.lfb_linelength = vminfo.logical_scan; 222 boot_params.screen_info.lfb_width = vminfo.h_res; 223 boot_params.screen_info.lfb_height = vminfo.v_res; 224 boot_params.screen_info.lfb_depth = vminfo.bpp; 225 boot_params.screen_info.pages = vminfo.image_planes; 226 boot_params.screen_info.lfb_base = vminfo.lfb_ptr; 227 memcpy(&boot_params.screen_info.red_size, 228 &vminfo.rmask, 8); 229 230 /* General parameters */ 231 boot_params.screen_info.lfb_size = vginfo.total_memory; 232 233 if (vminfo.bpp <= 8) 234 vesa_dac_set_8bits(); 235 236 vesa_store_pm_info(); 237 } 238 239 /* 240 * Save EDID information for the kernel; this is invoked, separately, 241 * after mode-setting. 242 */ 243 void vesa_store_edid(void) 244 { 245 #ifdef CONFIG_FIRMWARE_EDID 246 u16 ax, bx, cx, dx, di; 247 248 /* Apparently used as a nonsense token... */ 249 memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info); 250 251 if (vginfo.version < 0x0200) 252 return; /* EDID requires VBE 2.0+ */ 253 254 ax = 0x4f15; /* VBE DDC */ 255 bx = 0x0000; /* Report DDC capabilities */ 256 cx = 0; /* Controller 0 */ 257 di = 0; /* ES:DI must be 0 by spec */ 258 259 /* Note: The VBE DDC spec is different from the main VESA spec; 260 we genuinely have to assume all registers are destroyed here. */ 261 262 asm("pushw %%es; movw %2,%%es; "INT10"; popw %%es" 263 : "+a" (ax), "+b" (bx) 264 : "c" (cx), "D" (di) 265 : "esi"); 266 267 if (ax != 0x004f) 268 return; /* No EDID */ 269 270 /* BH = time in seconds to transfer EDD information */ 271 /* BL = DDC level supported */ 272 273 ax = 0x4f15; /* VBE DDC */ 274 bx = 0x0001; /* Read EDID */ 275 cx = 0; /* Controller 0 */ 276 dx = 0; /* EDID block number */ 277 di =(size_t) &boot_params.edid_info; /* (ES:)Pointer to block */ 278 asm(INT10 279 : "+a" (ax), "+b" (bx), "+d" (dx), "=m" (boot_params.edid_info) 280 : "c" (cx), "D" (di) 281 : "esi"); 282 #endif /* CONFIG_FIRMWARE_EDID */ 283 } 284 285 __videocard video_vesa = 286 { 287 .card_name = "VESA", 288 .probe = vesa_probe, 289 .set_mode = vesa_set_mode, 290 .xmode_first = VIDEO_FIRST_VESA, 291 .xmode_n = 0x200, 292 }; 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