/*
 * AGPGART module version 0.99
 * Copyright (C) 1999 Jeff Hartmann
 * Copyright (C) 1999 Precision Insight, Inc.
 * Copyright (C) 1999 Xi Graphics, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * JEFF HARTMANN, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM, 
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE 
 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#ifndef _AGP_BACKEND_H
#define _AGP_BACKEND_H 1

#ifndef TRUE
#define TRUE 1
#endif

#ifndef FALSE
#define FALSE 0
#endif

#define AGPGART_VERSION_MAJOR 0
#define AGPGART_VERSION_MINOR 99

enum chipset_type {
	NOT_SUPPORTED,
	INTEL_GENERIC,
	INTEL_LX,
	INTEL_BX,
	INTEL_GX,
	INTEL_I810,
	VIA_GENERIC,
	VIA_VP3,
	VIA_MVP3,
	VIA_APOLLO_PRO,
	SIS_GENERIC,
	AMD_GENERIC,
	AMD_IRONGATE,
	ALI_M1541,
	ALI_GENERIC
};

typedef struct _agp_version {
	u16 major;
	u16 minor;
} agp_version;

typedef struct _agp_kern_info {
	agp_version version;
	struct pci_dev *device;
	enum chipset_type chipset;
	unsigned long mode;
	off_t aper_base;
	size_t aper_size;
	int max_memory;		/* In pages */
	int current_memory;
} agp_kern_info;

/* 
 * The agp_memory structure has information
 * about the block of agp memory allocated.
 * A caller may manipulate the next and prev
 * pointers to link each allocated item into
 * a list.  These pointers are ignored by the 
 * backend.  Everything else should never be
 * written to, but the caller may read any of
 * the items to detrimine the status of this
 * block of agp memory.
 * 
 */

typedef struct _agp_memory {
	int key;
	struct _agp_memory *next;
	struct _agp_memory *prev;
	size_t page_count;
	int num_scratch_pages;
	unsigned long *memory;
	off_t pg_start;
	u32 type;
	u8 is_bound;
	u8 is_flushed;
} agp_memory;

#define AGP_NORMAL_MEMORY 0

extern void agp_free_memory(agp_memory *);

/*
 * agp_free_memory :
 * 
 * This function frees memory associated with
 * an agp_memory pointer.  It is the only function
 * that can be called when the backend is not owned
 * by the caller.  (So it can free memory on client
 * death.)
 * 
 * It takes an agp_memory pointer as an argument.
 * 
 */

extern agp_memory *agp_allocate_memory(size_t, u32);

/*
 * agp_allocate_memory :
 * 
 * This function allocates a group of pages of
 * a certain type.
 * 
 * It takes a size_t argument of the number of pages, and
 * an u32 argument of the type of memory to be allocated.  
 * Every agp bridge device will allow you to allocate 
 * AGP_NORMAL_MEMORY which maps to physical ram.  Any other
 * type is device dependant.
 * 
 * It returns NULL whenever memory is unavailable.
 * 
 */

extern void agp_copy_info(agp_kern_info *);

/*
 * agp_copy_info :
 * 
 * This function copies information about the
 * agp bridge device and the state of the agp
 * backend into an agp_kern_info pointer.
 * 
 * It takes an agp_kern_info pointer as an
 * argument.  The caller should insure that
 * this pointer is valid.
 * 
 */

extern int agp_bind_memory(agp_memory *, off_t);

/*
 * agp_bind_memory :
 * 
 * This function binds an agp_memory structure
 * into the graphics aperture translation table.
 * 
 * It takes an agp_memory pointer and an offset into
 * the graphics aperture translation table as arguments
 * 
 * It returns -EINVAL if the pointer == NULL.
 * It returns -EBUSY if the area of the table
 * requested is already in use.
 * 
 */

extern int agp_unbind_memory(agp_memory *);

/* 
 * agp_unbind_memory :
 * 
 * This function removes an agp_memory structure
 * from the graphics aperture translation table.
 * 
 * It takes an agp_memory pointer as an argument.
 * 
 * It returns -EINVAL if this piece of agp_memory
 * is not currently bound to the graphics aperture
 * translation table or if the agp_memory 
 * pointer == NULL
 * 
 */

extern void agp_enable(u32);

/* 
 * agp_enable :
 * 
 * This function initializes the agp point-to-point
 * connection.
 * 
 * It takes an agp mode register as an argument
 * 
 */

extern int agp_backend_acquire(void);

/*
 * agp_backend_acquire :
 * 
 * This Function attempts to acquire the agp
 * backend.
 * 
 * returns -EBUSY if agp is in use,
 * returns 0 if the caller owns the agp backend
 */

extern void agp_backend_release(void);

/*
 * agp_backend_release :
 * 
 * This Function releases the lock on the agp
 * backend.
 * 
 * The caller must insure that the graphics
 * aperture translation table is read for use
 * by another entity.  (Ensure that all memory
 * it bound is unbound.)
 * 
 */

#endif				/* _AGP_BACKEND_H */
