arch/x86/boot/video.h

   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 /*
  21  * This code uses an extended set of video mode numbers. These include:
  22  * Aliases for standard modes
  23  *      NORMAL_VGA (-1)
  24  *      EXTENDED_VGA (-2)
  25  *      ASK_VGA (-3)
  26  * Video modes numbered by menu position -- NOT RECOMMENDED because of lack
  27  * of compatibility when extending the table. These are between 0x00 and 0xff.
  28  */
  29 #define VIDEO_FIRST_MENU 0x0000
  30
  31 /* Standard BIOS video modes (BIOS number + 0x0100) */
  32 #define VIDEO_FIRST_BIOS 0x0100
  33
  34 /* VESA BIOS video modes (VESA number + 0x0200) */
  35 #define VIDEO_FIRST_VESA 0x0200
  36
  37 /* Video7 special modes (BIOS number + 0x0900) */
  38 #define VIDEO_FIRST_V7 0x0900
  39
  40 /* Special video modes */
  41 #define VIDEO_FIRST_SPECIAL 0x0f00
  42 #define VIDEO_80x25 0x0f00
  43 #define VIDEO_8POINT 0x0f01
  44 #define VIDEO_80x43 0x0f02
  45 #define VIDEO_80x28 0x0f03
  46 #define VIDEO_CURRENT_MODE 0x0f04
  47 #define VIDEO_80x30 0x0f05
  48 #define VIDEO_80x34 0x0f06
  49 #define VIDEO_80x60 0x0f07
  50 #define VIDEO_GFX_HACK 0x0f08
  51 #define VIDEO_LAST_SPECIAL 0x0f09
  52
  53 /* Video modes given by resolution */
  54 #define VIDEO_FIRST_RESOLUTION 0x1000
  55
  56 /* The "recalculate timings" flag */
  57 #define VIDEO_RECALC 0x8000
  58
  59 void store_screen(void);
  60 #define DO_STORE() store_screen()
  61
  62 /*
  63  * Mode table structures
  64  */
  65
  66 struct mode_info {
  67         u16 mode;               /* Mode number (vga= style) */
  68         u16 x, y;               /* Width, height */
  69         u16 depth;              /* Bits per pixel, 0 for text mode */
  70 };
  71
  72 struct card_info {
  73         const char *card_name;
  74         int (*set_mode)(struct mode_info *mode);
  75         int (*probe)(void);
  76         struct mode_info *modes;
  77         int nmodes;             /* Number of probed modes so far */
  78         int unsafe;             /* Probing is unsafe, only do after "scan" */
  79         u16 xmode_first;        /* Unprobed modes to try to call anyway */
  80         u16 xmode_n;            /* Size of unprobed mode range */
  81 };
  82
  83 #define __videocard struct card_info __attribute__((used,section(".videocards")))
  84 extern struct card_info video_cards[], video_cards_end[];
  85
  86 int mode_defined(u16 mode);     /* video.c */
  87
  88 /* Basic video information */
  89 #define ADAPTER_CGA     0       /* CGA/MDA/HGC */
  90 #define ADAPTER_EGA     1
  91 #define ADAPTER_VGA     2
  92
  93 extern int adapter;
  94 extern u16 video_segment;
  95 extern int force_x, force_y;    /* Don't query the BIOS for cols/rows */
  96 extern int do_restore;          /* Restore screen contents */
  97 extern int graphic_mode;        /* Graphics mode with linear frame buffer */
  98
  99 /* Accessing VGA indexed registers */
 100 static inline u8 in_idx(u16 port, u8 index)
 101 {
 102         outb(index, port);
 103         return inb(port+1);
 104 }
 105
 106 static inline void out_idx(u8 v, u16 port, u8 index)
 107 {
 108         outw(index+(v << 8), port);
 109 }
 110
 111 /* Writes a value to an indexed port and then reads the port again */
 112 static inline u8 tst_idx(u8 v, u16 port, u8 index)
 113 {
 114         out_idx(port, index, v);
 115         return in_idx(port, index);
 116 }
 117
 118 /* Get the I/O port of the VGA CRTC */
 119 u16 vga_crtc(void);             /* video-vga.c */
 120
 121 #endif /* BOOT_VIDEO_H */