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