[PATCH] gx1fb: (try to) play nicer with various BIOSes

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / video / amifb.c

/*
 * linux/drivers/video/amifb.c -- Amiga builtin chipset frame buffer device
 *
 *    Copyright (C) 1995-2003 Geert Uytterhoeven
 *
 *          with work by Roman Zippel
 *
 *
 * This file is based on the Atari frame buffer device (atafb.c):
 *
 *    Copyright (C) 1994 Martin Schaller
 *                       Roman Hodek
 *
 *          with work by Andreas Schwab
 *                       Guenther Kelleter
 *
 * and on the original Amiga console driver (amicon.c):
 *
 *    Copyright (C) 1993 Hamish Macdonald
 *                       Greg Harp
 *    Copyright (C) 1994 David Carter [carter@compsci.bristol.ac.uk]
 *
 *          with work by William Rucklidge (wjr@cs.cornell.edu)
 *                       Geert Uytterhoeven
 *                       Jes Sorensen (jds@kom.auc.dk)
 *
 *
 * History:
 *
 *   - 24 Jul 96: Copper generates now vblank interrupt and
 *                VESA Power Saving Protocol is fully implemented
 *   - 14 Jul 96: Rework and hopefully last ECS bugs fixed
 *   -  7 Mar 96: Hardware sprite support by Roman Zippel
 *   - 18 Feb 96: OCS and ECS support by Roman Zippel
 *                Hardware functions completely rewritten
 *   -  2 Dec 95: AGA version by Geert Uytterhoeven
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file COPYING in the main directory of this archive
 * for more details.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/config.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/ioport.h>

#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/irq.h>
#include <asm/amigahw.h>
#include <asm/amigaints.h>
#include <asm/setup.h>

#include "c2p.h"


#define DEBUG

#if !defined(CONFIG_FB_AMIGA_OCS) && !defined(CONFIG_FB_AMIGA_ECS) && !defined(CONFIG_FB_AMIGA_AGA)
#define CONFIG_FB_AMIGA_OCS   /* define at least one fb driver, this will change later */
#endif

#if !defined(CONFIG_FB_AMIGA_OCS)
#  define IS_OCS (0)
#elif defined(CONFIG_FB_AMIGA_ECS) || defined(CONFIG_FB_AMIGA_AGA)
#  define IS_OCS (chipset == TAG_OCS)
#else
#  define CONFIG_FB_AMIGA_OCS_ONLY
#  define IS_OCS (1)
#endif

#if !defined(CONFIG_FB_AMIGA_ECS)
#  define IS_ECS (0)
#elif defined(CONFIG_FB_AMIGA_OCS) || defined(CONFIG_FB_AMIGA_AGA)
#  define IS_ECS (chipset == TAG_ECS)
#else
#  define CONFIG_FB_AMIGA_ECS_ONLY
#  define IS_ECS (1)
#endif

#if !defined(CONFIG_FB_AMIGA_AGA)
#  define IS_AGA (0)
#elif defined(CONFIG_FB_AMIGA_OCS) || defined(CONFIG_FB_AMIGA_ECS)
#  define IS_AGA (chipset == TAG_AGA)
#else
#  define CONFIG_FB_AMIGA_AGA_ONLY
#  define IS_AGA (1)
#endif

#ifdef DEBUG
#  define DPRINTK(fmt, args...)	printk(KERN_DEBUG "%s: " fmt, __FUNCTION__ , ## args)
#else
#  define DPRINTK(fmt, args...)
#endif

/*******************************************************************************


   Generic video timings
   ---------------------

   Timings used by the frame buffer interface:

   +----------+---------------------------------------------+----------+-------+
   |          |                ^                            |          |       |
   |          |                |upper_margin                |          |       |