1 /* ----------------------------------------------------------------------- * 2 * 3 * Copyright 1999-2008 H. Peter Anvin - All Rights Reserved 4 * Copyright 2009 Intel Corporation; author: H. Peter Anvin 5 * 6 * Permission is hereby granted, free of charge, to any person 7 * obtaining a copy of this software and associated documentation 8 * files (the "Software"), to deal in the Software without 9 * restriction, including without limitation the rights to use, 10 * copy, modify, merge, publish, distribute, sublicense, and/or 11 * sell copies of the Software, and to permit persons to whom 12 * the Software is furnished to do so, subject to the following 13 * conditions: 14 * 15 * The above copyright notice and this permission notice shall 16 * be included in all copies or substantial portions of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 19 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 20 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 21 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 22 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 23 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 24 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 25 * OTHER DEALINGS IN THE SOFTWARE. 26 * 27 * ----------------------------------------------------------------------- */ 28 29 /* 30 * initvesa.c 31 * 32 * Query the VESA BIOS and select a 640x480x32 mode with local mapping 33 * support, if one exists. 34 */ 35 36 #include <inttypes.h> 37 #include <com32.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <limits.h> 41 #include <graphics.h> 42 43 #include "vesa.h" 44 #include "mboot.h" 45 46 struct vesa_info vesa_info; 47 48 void set_graphics_mode(const struct multiboot_header *mbh, 49 struct multiboot_info *mbi) 50 { 51 com32sys_t rm; 52 uint16_t mode, bestmode, *mode_ptr; 53 struct vesa_general_info *gi; 54 struct vesa_mode_info *mi; 55 int pxf, bestpxf; 56 int wantx, wanty; 57 int err, besterr; 58 bool better; 59 addr_t viaddr; 60 61 /* Only do this if requested by the OS image */ 62 if (!(mbh->flags & MULTIBOOT_VIDEO_MODE) || mbh->mode_type != 0) 63 return; 64 65 gi = lmalloc(sizeof *gi); 66 if (!gi) 67 return; 68 69 mi = lmalloc(sizeof *mi); 70 if (!mi) 71 goto out; 72 73 memset(&rm, 0, sizeof rm); 74 memset(gi, 0, sizeof *gi); 75 76 gi->signature = VBE2_MAGIC; /* Get VBE2 extended data */ 77 rm.eax.w[0] = 0x4F00; /* Get SVGA general information */ 78 rm.edi.w[0] = OFFS(gi); 79 rm.es = SEG(gi); 80 __intcall(0x10, &rm, &rm); 81 82 if (rm.eax.w[0] != 0x004F) 83 goto out; /* Function call failed */ 84 if (gi->signature != VESA_MAGIC) 85 goto out; /* No magic */ 86 if (gi->version < 0x0102) 87 goto out; /* VESA 1.2+ required */ 88 89 memcpy(&vesa_info.gi, gi, sizeof *gi); 90 91 /* Search for a suitable mode with a suitable color and memory model... */ 92 93 mode_ptr = GET_PTR(gi->video_mode_ptr); 94 bestmode = 0; 95 bestpxf = 0; 96 wantx = mbh->width ? mbh->width : 0xffff; 97 wanty = mbh->height ? mbh->height : 0xffff; 98 besterr = wantx + wanty; 99 100 while ((mode = *mode_ptr++) != 0xFFFF) { 101 mode &= 0x1FF; /* The rest are attributes of sorts */ 102 103 memset(&rm, 0, sizeof rm); 104 memset(mi, 0, sizeof *mi); 105 rm.eax.w[0] = 0x4F01; /* Get SVGA mode information */ 106 rm.ecx.w[0] = mode; 107 rm.edi.w[0] = OFFS(mi); 108 rm.es = SEG(mi); 109 __intcall(0x10, &rm, &rm); 110 111 /* Must be a supported mode */ 112 if (rm.eax.w[0] != 0x004f) 113 continue; 114 115 /* Must be an LFB color graphics mode supported by the hardware. 116 117 The bits tested are: 118 7 - linear frame buffer 119 4 - graphics mode 120 3 - color mode 121 1 - mode information available (mandatory in VBE 1.2+) 122 0 - mode supported by hardware 123 */ 124 if ((mi->mode_attr & 0x009b) != 0x009b) 125 continue; 126 127 /* We don't support multibank (interlaced memory) modes */ 128 /* 129 * Note: The Bochs VESA BIOS (vbe.c 1.58 2006/08/19) violates the 130 * specification which states that banks == 1 for unbanked modes; 131 * fortunately it does report bank_size == 0 for those. 132 */ 133 if (mi->banks > 1 && mi->bank_size) 134 continue; 135 136 /* Must either be a packed-pixel mode or a direct color mode 137 (depending on VESA version ); must be a supported pixel format */ 138 139 if (mi->bpp == 32 && 140 (mi->memory_layout == 4 || 141 (mi->memory_layout == 6 && mi->rpos == 16 && mi->gpos == 8 && 142 mi->bpos == 0))) 143 pxf = 32; 144 else if (mi->bpp == 24 && 145 (mi->memory_layout == 4 || 146 (mi->memory_layout == 6 && mi->rpos == 16 && mi->gpos == 8 && 147 mi->bpos == 0))) 148 pxf = 24; 149 else if (mi->bpp == 16 && 150 (mi->memory_layout == 4 || 151 (mi->memory_layout == 6 && mi->rpos == 11 && mi->gpos == 5 && 152 mi->bpos == 0))) 153 pxf = 16; 154 else if (mi->bpp == 15 && 155 (mi->memory_layout == 4 || 156 (mi->memory_layout == 6 && mi->rpos == 10 && mi->gpos == 5 && 157 mi->bpos == 0))) 158 pxf = 15; 159 else 160 continue; 161 162 better = false; 163 err = abs(mi->h_res - wantx) + abs(mi->v_res - wanty); 164 165 #define IS_GOOD(mi, bestx, besty) \ 166 ((mi)->h_res >= (bestx) && (mi)->v_res >= (besty)) 167 168 if (!bestpxf) 169 better = true; 170 else if (!IS_GOOD(&vesa_info.mi, wantx, wanty) && 171 IS_GOOD(mi, wantx, wanty)) 172 /* This matches criteria, which the previous one didn't */ 173 better = true; 174 else if (IS_GOOD(&vesa_info.mi, wantx, wanty) && 175 !IS_GOOD(mi, wantx, wanty)) 176 /* This doesn't match criteria, and the previous one did */ 177 better = false; 178 else if (err < besterr) 179 better = true; 180 else if (err == besterr && (pxf == (int)mbh->depth || pxf > bestpxf)) 181 better = true; 182 183 if (better) { 184 bestmode = mode; 185 bestpxf = pxf; 186 memcpy(&vesa_info.mi, mi, sizeof *mi); 187 } 188 } 189 190 if (!bestpxf) 191 goto out; /* No mode found */ 192 193 mi = &vesa_info.mi; 194 mode = bestmode; 195 196 /* Now set video mode */ 197 memset(&rm, 0, sizeof rm); 198 rm.eax.w[0] = 0x4F02; /* Set SVGA video mode */ 199 mode |= 0x4000; /* Request linear framebuffer */ 200 rm.ebx.w[0] = mode; 201 __intcall(0x10, &rm, &rm); 202 if (rm.eax.w[0] != 0x004F) 203 goto out; /* Failed to set mode */ 204 205 mbi->flags |= MB_INFO_VIDEO_INFO; 206 mbi->vbe_mode = mode; 207 viaddr = map_data(&vesa_info, sizeof vesa_info, 4, 0); 208 mbi->vbe_control_info = viaddr + offsetof(struct vesa_info, gi); 209 mbi->vbe_mode_info = viaddr + offsetof(struct vesa_info, mi); 210 211 /* Get the VBE 2.x PM entry point if supported */ 212 rm.eax.w[0] = 0x4F0A; 213 rm.ebx.w[0] = 0; 214 __intcall(0x10, &rm, &rm); 215 if (rm.eax.w[0] == 0x004F) { 216 mbi->vbe_interface_seg = rm.es; 217 mbi->vbe_interface_off = rm.edi.w[0]; 218 mbi->vbe_interface_len = rm.ecx.w[0]; 219 } 220 221 /* In theory this should be: 222 * 223 * UsingVga = (mi->mode_attr & 4) ? 0x0007 : 0x000f; 224 * 225 * However, that would assume all systems that claim to handle text 226 * output in VESA modes actually do that... 227 */ 228 graphics_using_vga(0x0F, vesa_info.mi.h_res, vesa_info.mi.v_res); 229 230 out: 231 lfree(mi); 232 lfree(gi); 233 } 234
