/* ----------------------------------------------------------------------- * * * Copyright 1999-2008 H. Peter Anvin - All Rights Reserved * Copyright 2009 Intel Corporation; author: H. Peter Anvin * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or * sell copies of the Software, and to permit persons to whom * the Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall * be included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. * * ----------------------------------------------------------------------- */ /* * initvesa.c * * Query the VESA BIOS and select a 640x480x32 mode with local mapping * support, if one exists. */ #include #include #include #include #include #include "vesa.h" #include "mboot.h" struct vesa_info vesa_info; void set_graphics_mode(const struct multiboot_header *mbh, struct multiboot_info *mbi) { com32sys_t rm; uint16_t mode, bestmode, *mode_ptr; struct vesa_general_info *gi; struct vesa_mode_info *mi; int pxf, bestpxf; int wantx, wanty; int err, besterr; bool better; addr_t viaddr; /* Only do this if requested by the OS image */ if (!(mbh->flags & MULTIBOOT_VIDEO_MODE) || mbh->mode_type != 0) return; /* Allocate space in the bounce buffer for these structures */ gi = &((struct vesa_info *)__com32.cs_bounce)->gi; mi = &((struct vesa_info *)__com32.cs_bounce)->mi; memset(&rm, 0, sizeof rm); memset(gi, 0, sizeof *gi); gi->signature = VBE2_MAGIC; /* Get VBE2 extended data */ rm.eax.w[0] = 0x4F00; /* Get SVGA general information */ rm.edi.w[0] = OFFS(gi); rm.es = SEG(gi); __intcall(0x10, &rm, &rm); if (rm.eax.w[0] != 0x004F) return; /* Function call failed */ if (gi->signature != VESA_MAGIC) return; /* No magic */ if (gi->version < 0x0102) return; /* VESA 1.2+ required */ memcpy(&vesa_info.gi, gi, sizeof *gi); /* Search for a suitable mode with a suitable color and memory model... */ mode_ptr = GET_PTR(gi->video_mode_ptr); bestmode = 0; bestpxf = 0; wantx = mbh->width ? mbh->width : 0xffff; wanty = mbh->height ? mbh->height : 0xffff; besterr = wantx + wanty; while ((mode = *mode_ptr++) != 0xFFFF) { mode &= 0x1FF; /* The rest are attributes of sorts */ memset(mi, 0, sizeof *mi); rm.eax.w[0] = 0x4F01; /* Get SVGA mode information */ rm.ecx.w[0] = mode; rm.edi.w[0] = OFFS(mi); rm.es = SEG(mi); __intcall(0x10, &rm, &rm); /* Must be a supported mode */ if (rm.eax.w[0] != 0x004f) continue; /* Must be an LFB color graphics mode supported by the hardware. The bits tested are: 7 - linear frame buffer 4 - graphics mode 3 - color mode 1 - mode information available (mandatory in VBE 1.2+) 0 - mode supported by hardware */ if ((mi->mode_attr & 0x009b) != 0x009b) continue; /* We don't support multibank (interlaced memory) modes */ /* * Note: The Bochs VESA BIOS (vbe.c 1.58 2006/08/19) violates the * specification which states that banks == 1 for unbanked modes; * fortunately it does report bank_size == 0 for those. */ if (mi->banks > 1 && mi->bank_size) continue; /* Must either be a packed-pixel mode or a direct color mode (depending on VESA version ); must be a supported pixel format */ if (mi->bpp == 32 && (mi->memory_layout == 4 || (mi->memory_layout == 6 && mi->rpos == 16 && mi->gpos == 8 && mi->bpos == 0))) pxf = 32; else if (mi->bpp == 24 && (mi->memory_layout == 4 || (mi->memory_layout == 6 && mi->rpos == 16 && mi->gpos == 8 && mi->bpos == 0))) pxf = 24; else if (mi->bpp == 16 && (mi->memory_layout == 4 || (mi->memory_layout == 6 && mi->rpos == 11 && mi->gpos == 5 && mi->bpos == 0))) pxf = 16; else if (mi->bpp == 15 && (mi->memory_layout == 4 || (mi->memory_layout == 6 && mi->rpos == 10 && mi->gpos == 5 && mi->bpos == 0))) pxf = 15; else continue; better = false; err = abs(mi->h_res - wantx) + abs(mi->v_res - wanty); #define IS_GOOD(mi, bestx, besty) \ ((mi)->h_res >= (bestx) && (mi)->v_res >= (besty)) if (!bestpxf) better = true; else if (!IS_GOOD(&vesa_info.mi, wantx, wanty) && IS_GOOD(mi, wantx, wanty)) /* This matches criteria, which the previous one didn't */ better = true; else if (IS_GOOD(&vesa_info.mi, wantx, wanty) && !IS_GOOD(mi, wantx, wanty)) /* This doesn't match criteria, and the previous one did */ better = false; else if (err < besterr) better = true; else if (err == besterr && (pxf == (int)mbh->depth || pxf > bestpxf)) better = true; if (better) { bestmode = mode; bestpxf = pxf; memcpy(&vesa_info.mi, mi, sizeof *mi); } } if (!bestpxf) return; /* No mode found */ mi = &vesa_info.mi; mode = bestmode; /* Now set video mode */ rm.eax.w[0] = 0x4F02; /* Set SVGA video mode */ mode |= 0x4000; /* Request linear framebuffer */ rm.ebx.w[0] = mode; __intcall(0x10, &rm, &rm); if (rm.eax.w[0] != 0x004F) return; /* Failed to set mode */ mbi->flags |= MB_INFO_VIDEO_INFO; mbi->vbe_mode = mode; viaddr = map_data(&vesa_info, sizeof vesa_info, 4, 0); mbi->vbe_control_info = viaddr + offsetof(struct vesa_info, gi); mbi->vbe_mode_info = viaddr + offsetof(struct vesa_info, mi); /* Get the VBE 2.x PM entry point if supported */ rm.eax.w[0] = 0x4F0A; rm.ebx.w[0] = 0; __intcall(0x10, &rm, &rm); if (rm.eax.w[0] == 0x004F) { mbi->vbe_interface_seg = rm.es; mbi->vbe_interface_off = rm.edi.w[0]; mbi->vbe_interface_len = rm.ecx.w[0]; } /* Tell syslinux we changed video mode */ rm.eax.w[0] = 0x0017; /* Report video mode change */ /* In theory this should be: rm.ebx.w[0] = (mi->mode_attr & 4) ? 0x0007 : 0x000f; However, that would assume all systems that claim to handle text output in VESA modes actually do that... */ rm.ebx.w[0] = 0x000f; rm.ecx.w[0] = vesa_info.mi.h_res; rm.edx.w[0] = vesa_info.mi.v_res; __intcall(0x22, &rm, NULL); }