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.h 13 * 14 * Header file for the real-mode video probing code 15 */ 16 17 #ifndef BOOT_VIDEO_H 18 #define BOOT_VIDEO_H 19 20 #include <linux/types.h> 21 22 /* Enable autodetection of SVGA adapters and modes. */ 23 #undef CONFIG_VIDEO_SVGA 24 25 /* Enable autodetection of VESA modes */ 26 #define CONFIG_VIDEO_VESA 27 28 /* Retain screen contents when switching modes */ 29 #define CONFIG_VIDEO_RETAIN 30 31 /* Force 400 scan lines for standard modes (hack to fix bad BIOS behaviour */ 32 #undef CONFIG_VIDEO_400_HACK 33 34 /* This code uses an extended set of video mode numbers. These include: 35 * Aliases for standard modes 36 * NORMAL_VGA (-1) 37 * EXTENDED_VGA (-2) 38 * ASK_VGA (-3) 39 * Video modes numbered by menu position -- NOT RECOMMENDED because of lack 40 * of compatibility when extending the table. These are between 0x00 and 0xff. 41 */ 42 #define VIDEO_FIRST_MENU 0x0000 43 44 /* Standard BIOS video modes (BIOS number + 0x0100) */ 45 #define VIDEO_FIRST_BIOS 0x0100 46 47 /* VESA BIOS video modes (VESA number + 0x0200) */ 48 #define VIDEO_FIRST_VESA 0x0200 49 50 /* Video7 special modes (BIOS number + 0x0900) */ 51 #define VIDEO_FIRST_V7 0x0900 52 53 /* Special video modes */ 54 #define VIDEO_FIRST_SPECIAL 0x0f00 55 #define VIDEO_80x25 0x0f00 56 #define VIDEO_8POINT 0x0f01 57 #define VIDEO_80x43 0x0f02 58 #define VIDEO_80x28 0x0f03 59 #define VIDEO_CURRENT_MODE 0x0f04 60 #define VIDEO_80x30 0x0f05 61 #define VIDEO_80x34 0x0f06 62 #define VIDEO_80x60 0x0f07 63 #define VIDEO_GFX_HACK 0x0f08 64 #define VIDEO_LAST_SPECIAL 0x0f09 65 66 /* Video modes given by resolution */ 67 #define VIDEO_FIRST_RESOLUTION 0x1000 68 69 /* The "recalculate timings" flag */ 70 #define VIDEO_RECALC 0x8000 71 72 /* Define DO_STORE according to CONFIG_VIDEO_RETAIN */ 73 #ifdef CONFIG_VIDEO_RETAIN 74 void store_screen(void); 75 #define DO_STORE() store_screen() 76 #else 77 #define DO_STORE() ((void)0) 78 #endif /* CONFIG_VIDEO_RETAIN */ 79 80 /* 81 * Mode table structures 82 */ 83 84 struct mode_info { 85 u16 mode; /* Mode number (vga= style) */ 86 u16 x, y; /* Width, height */ 87 u16 depth; /* Bits per pixel, 0 for text mode */ 88 }; 89 90 struct card_info { 91 const char *card_name; 92 int (*set_mode)(struct mode_info *mode); 93 int (*probe)(void); 94 struct mode_info *modes; 95 int nmodes; /* Number of probed modes so far */ 96 int unsafe; /* Probing is unsafe, only do after "scan" */ 97 u16 xmode_first; /* Unprobed modes to try to call anyway */ 98 u16 xmode_n; /* Size of unprobed mode range */ 99 }; 100 101 #define __videocard struct card_info __attribute__((section(".videocards"))) 102 extern struct card_info video_cards[], video_cards_end[]; 103 104 int mode_defined(u16 mode); /* video.c */ 105 106 /* Basic video information */ 107 #define ADAPTER_CGA 0 /* CGA/MDA/HGC */ 108 #define ADAPTER_EGA 1 109 #define ADAPTER_VGA 2 110 111 extern int adapter; 112 extern u16 video_segment; 113 extern int force_x, force_y; /* Don't query the BIOS for cols/rows */ 114 extern int do_restore; /* Restore screen contents */ 115 extern int graphic_mode; /* Graphics mode with linear frame buffer */ 116 117 /* 118 * int $0x10 is notorious for touching registers it shouldn't. 119 * gcc doesn't like %ebp being clobbered, so define it as a push/pop 120 * sequence here. 121 * 122 * A number of systems, including the original PC can clobber %bp in 123 * certain circumstances, like when scrolling. There exists at least 124 * one Trident video card which could clobber DS under a set of 125 * circumstances that we are unlikely to encounter (scrolling when 126 * using an extended graphics mode of more than 800x600 pixels), but 127 * it's cheap insurance to deal with that here. 128 */ 129 #define INT10 "pushl %%ebp; pushw %%ds; int $0x10; popw %%ds; popl %%ebp" 130 131 /* Accessing VGA indexed registers */ 132 static inline u8 in_idx(u16 port, u8 index) 133 { 134 outb(index, port); 135 return inb(port+1); 136 } 137 138 static inline void out_idx(u8 v, u16 port, u8 index) 139 { 140 outw(index+(v << 8), port); 141 } 142 143 /* Writes a value to an indexed port and then reads the port again */ 144 static inline u8 tst_idx(u8 v, u16 port, u8 index) 145 { 146 out_idx(port, index, v); 147 return in_idx(port, index); 148 } 149 150 /* Get the I/O port of the VGA CRTC */ 151 u16 vga_crtc(void); /* video-vga.c */ 152 153 #endif /* BOOT_VIDEO_H */ 154