LXR linux/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
  59void store_screen(void);
  60#define DO_STORE() store_screen()
  61
  62/*
  63 * Mode table structures
  64 */
  65
  66struct 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
  72struct 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__((section(".videocards")))
  84extern struct card_info video_cards[], video_cards_end[];
  85
  86int 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
  93extern int adapter;
  94extern u16 video_segment;
  95extern int force_x, force_y;    /* Don't query the BIOS for cols/rows */
  96extern int do_restore;          /* Restore screen contents */
  97extern int graphic_mode;        /* Graphics mode with linear frame buffer */
  98
  99/* Accessing VGA indexed registers */
 100static inline u8 in_idx(u16 port, u8 index)
 101{
 102        outb(index, port);
 103        return inb(port+1);
 104}
 105
 106static 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 */
 112static 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 */
 119u16 vga_crtc(void);             /* video-vga.c */
 120
 121#endif /* BOOT_VIDEO_H */
 122