/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007 rPath, Inc. - All Rights Reserved
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2.
*
* ----------------------------------------------------------------------- */
/*
* Header file for the real-mode video probing code
*/
#ifndef BOOT_VIDEO_H
#define BOOT_VIDEO_H
#include <linux/types.h>
/* Enable autodetection of SVGA adapters and modes. */
#undef CONFIG_VIDEO_SVGA
/* Enable autodetection of VESA modes */
#define CONFIG_VIDEO_VESA
/* Retain screen contents when switching modes */
#define CONFIG_VIDEO_RETAIN
/* Force 400 scan lines for standard modes (hack to fix bad BIOS behaviour */
#undef CONFIG_VIDEO_400_HACK
/* This code uses an extended set of video mode numbers. These include:
* Aliases for standard modes
* NORMAL_VGA (-1)
* EXTENDED_VGA (-2)
* ASK_VGA (-3)
* Video modes numbered by menu position -- NOT RECOMMENDED because of lack
* of compatibility when extending the table. These are between 0x00 and 0xff.
*/
#define VIDEO_FIRST_MENU 0x0000
/* Standard BIOS video modes (BIOS number + 0x0100) */
#define VIDEO_FIRST_BIOS 0x0100
/* VESA BIOS video modes (VESA number + 0x0200) */
#define VIDEO_FIRST_VESA 0x0200
/* Video7 special modes (BIOS number + 0x0900) */
#define VIDEO_FIRST_V7 0x0900
/* Special video modes */
#define VIDEO_FIRST_SPECIAL 0x0f00
#define VIDEO_80x25 0x0f00
#define VIDEO_8POINT 0x0f01
#define VIDEO_80x43 0x0f02
#define VIDEO_80x28 0x0f03
#define VIDEO_CURRENT_MODE 0x0f04
#define VIDEO_80x30 0x0f05
#define VIDEO_80x34 0x0f06
#define VIDEO_80x60 0x0f07
#define VIDEO_GFX_HACK 0x0f08
#define VIDEO_LAST_SPECIAL 0x0f09
/* Video modes given by resolution */
#define VIDEO_FIRST_RESOLUTION 0x1000
/* The "recalculate timings" flag */
#define VIDEO_RECALC 0x8000
/* Define DO_STORE according to CONFIG_VIDEO_RETAIN */
#ifdef CONFIG_VIDEO_RETAIN
void store_screen(void);
#define DO_STORE() store_screen()
#else
#define DO_STORE() ((void)0)
#endif /* CONFIG_VIDEO_RETAIN */
/*
* Mode table structures
*/
struct mode_info {
u16 mode; /* Mode number (vga= style) */
u16 x, y; /* Width, height */
u16 depth; /* Bits per pixel, 0 for text mode */
};
struct card_info {
const char *card_name;
int (*set_mode)(struct mode_info *mode);
int (*probe)(void);
struct mode_info *modes;
int nmodes; /* Number of probed modes so far */
int unsafe; /* Probing is unsafe, only do after "scan" */
u16 xmode_first; /* Unprobed modes to try to call anyway */
u16 xmode_n; /* Size of unprobed mode range */
};
#define __videocard struct card_info __attribute__((section(".videocards")))
extern struct card_info video_cards[], video_cards_end[];
int mode_defined(u16 mode); /* video.c */
/* Basic video information */
#define ADAPTER_CGA 0 /* CGA/MDA/HGC */
#define ADAPTER_EGA 1
#define ADAPTER_VGA 2
extern int adapter;
extern u16 video_segment;
extern int force_x, force_y; /* Don't query the BIOS for cols/rows */
extern int do_restore; /* Restore screen contents */
extern int graphic_mode; /* Graphics mode with linear frame buffer */
/*
* int $0x10 is notorious for touching registers it shouldn't.
* gcc doesn't like %ebp being clobbered, so define it as a push/pop
* sequence here.
*
* A number of systems, including the original PC can clobber %bp in
* certain circumstances, like when scrolling. There exists at least
* one Trident video card which could clobber DS under a set of
* circumstances that we are unlikely to encounter (scrolling when
* using an extended graphics mode of more than 800x600 pixels), but
* it's cheap insurance to deal with that here.
*/
#define INT10 "pushl %%ebp; pushw %%ds; int $0x10; popw %%ds; popl %%ebp"
/* Accessing VGA indexed registers */
static inline u8 in_idx(u16 port, u8 index)
{
outb(index, port);
return inb(port+1);
}
static inline void out_idx(u8 v, u16 port, u8 index)
{
outw(index+(v << 8), port);
}
/* Writes a value to an indexed port and then reads the port again */
static inline u8 tst_idx(u8 v, u16 port, u8 index)
{
out_idx(port, index, v);
return in_idx(port, index);
}
/* Get the I/O port of the VGA CRTC */
u16 vga_crtc(void); /* video-vga.c */
#endif /* BOOT_VIDEO_H */
