freebsd/sys/powerpc/include/bus.h

/*-
 * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
 * NASA Ames Research Center.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the NetBSD
 *	Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Copyright (c) 1996 Charles M. Hannum.  All rights reserved.
 * Copyright (c) 1996 Christopher G. Demetriou.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Christopher G. Demetriou
 *	for the NetBSD Project.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *	$NetBSD: bus.h,v 1.9.4.1 2000/06/30 16:27:30 simonb Exp $
 * $FreeBSD$
 */

#ifndef	_MACPPC_BUS_H_
#define	_MACPPC_BUS_H_

#include <machine/pio.h>

#define BUS_SPACE_MAXSIZE_24BIT 0xFFFFFF
#define BUS_SPACE_MAXSIZE_32BIT 0xFFFFFFFF
#define BUS_SPACE_MAXSIZE       (128 * 1024) /* Maximum supported size */
#define BUS_SPACE_MAXADDR_24BIT 0xFFFFFF
#define BUS_SPACE_MAXADDR_32BIT 0xFFFFFFFF
#define BUS_SPACE_MAXADDR       0xFFFFFFFF

#define BUS_SPACE_UNRESTRICTED  (~0)

/*
 * Values for the macppc bus space tag, not to be used directly by MI code.
 */

#define	__BUS_SPACE_HAS_STREAM_METHODS

/*
 * Values for the ppc bus space tag, not to be used directly by MI code.
 */
#define PPC_BUS_SPACE_MEM      1       /* space is mem space */


#define	__BA(t, h, o) ((void *)((h) + (o)))

/*
 * Bus address and size types
 */
typedef u_int32_t bus_addr_t;
typedef u_int32_t bus_size_t;

/*
 * Access methods for bus resources and address space.
 */
typedef u_int32_t bus_space_tag_t;
typedef u_int32_t bus_space_handle_t;

static __inline void *
__ppc_ba(bus_space_tag_t tag, bus_space_handle_t handle, bus_size_t offset)
{
	return ((void *)(handle + offset));
}


/*
 *	int bus_space_map(bus_space_tag_t t, bus_addr_t addr,
 *	    bus_size_t size, int flags, bus_space_handle_t *bshp));
 *
 * Map a region of bus space.
 */
#if 0
bus_space_map(t, addr, size, flags, bshp) ! not implemented !
#endif

/*
 *	int bus_space_unmap(bus_space_tag_t t,
 *	    bus_space_handle_t bsh, bus_size_t size));
 *
 * Unmap a region of bus space.
 */

#define bus_space_unmap(t, bsh, size)

/*
 *	int bus_space_subregion(bus_space_tag_t t,
 *	    bus_space_handle_t bsh, bus_size_t offset, bus_size_t size,
 *	    bus_space_handle_t *nbshp));
 *
 * Get a new handle for a subregion of an already-mapped area of bus space.
 */

#define	bus_space_subregion(t, bsh, offset, size, bshp)			\
	((*(bshp) = (bus_space_handle_t)__ppc_ba(t, bsh, offset)), 0)

/*
 *	int bus_space_alloc(bus_space_tag_t t, bus_addr_t rstart,
 *	    bus_addr_t rend, bus_size_t size, bus_size_t align,
 *	    bus_size_t boundary, int flags, bus_addr_t *addrp,
 *	    bus_space_handle_t *bshp));
 *
 * Allocate a region of bus space.
 */

#if 0
#define	bus_space_alloc(t, rs, re, s, a, b, f, ap, hp)	!!! unimplemented !!!
#endif

/*
 *	int bus_space_free(bus_space_tag_t t,
 *	    bus_space_handle_t bsh, bus_size_t size));
 *
 * Free a region of bus space.
 */
#if 0
#define	bus_space_free(t, h, s)		!!! unimplemented !!!
#endif

/*
 *	u_intN_t bus_space_read_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset));
 *
 * Read a 1, 2, 4, or 8 byte quantity from bus space
 * described by tag/handle/offset.
 */

#define	bus_space_read_1(t, h, o)	(in8(__ppc_ba(t, h, o)))
#define	bus_space_read_2(t, h, o)	(in16rb(__ppc_ba(t, h, o)))
#define	bus_space_read_4(t, h, o)	(in32rb(__ppc_ba(t, h, o)))
#if 0	/* Cause a link error for bus_space_read_8 */
#define	bus_space_read_8(t, h, o)	!!! unimplemented !!!
#endif

#define	bus_space_read_stream_1(t, h, o)	(in8(__ppc_ba(t, h, o)))
#define	bus_space_read_stream_2(t, h, o)	(in16(__ppc_ba(t, h, o)))
#define	bus_space_read_stream_4(t, h, o)	(in32(__ppc_ba(t, h, o)))
#if 0	/* Cause a link error for bus_space_read_stream_8 */
#define	bus_space_read_8(t, h, o)	!!! unimplemented !!!
#endif

/*
 *	void bus_space_read_multi_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset,
 *	    u_intN_t *addr, size_t count));
 *
 * Read `count' 1, 2, 4, or 8 byte quantities from bus space
 * described by tag/handle/offset and copy into buffer provided.
 */

#define	bus_space_read_multi_1(t, h, o, a, c) do {			\
		ins8(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#define	bus_space_read_multi_2(t, h, o, a, c) do {			\
		ins16rb(__ppc_ba(t, h, o), (a), (c));			\
	} while (0)

#define	bus_space_read_multi_4(t, h, o, a, c) do {			\
		ins32rb(__ppc_ba(t, h, o), (a), (c));			\
	} while (0)

#if 0	/* Cause a link error for bus_space_read_multi_8 */
#define	bus_space_read_multi_8		!!! unimplemented !!!
#endif

#define	bus_space_read_multi_stream_1(t, h, o, a, c) do {		\
		ins8(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#define	bus_space_read_multi_stream_2(t, h, o, a, c) do {		\
		ins16(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#define	bus_space_read_multi_stream_4(t, h, o, a, c) do {		\
		ins32(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#if 0	/* Cause a link error for bus_space_read_multi_stream_8 */
#define	bus_space_read_multi_stream_8	!!! unimplemented !!!
#endif

/*
 *	void bus_space_read_region_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset,
 *	    u_intN_t *addr, size_t count));
 *
 * Read `count' 1, 2, 4, or 8 byte quantities from bus space
 * described by tag/handle and starting at `offset' and copy into
 * buffer provided.
 */

static __inline void
bus_space_read_region_1(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int8_t *addr, size_t count)
{
	volatile u_int8_t *s = __ppc_ba(tag, bsh, offset);

	while (count--)
		*addr++ = *s++;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_read_region_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int16_t *addr, size_t count)
{
	volatile u_int16_t *s = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("lhbrx %0, 0, %1" :
			"=r"(*addr++) : "r"(s++));
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_read_region_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int32_t *addr, size_t count)
{
	volatile u_int32_t *s = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("lwbrx %0, 0, %1" :
			"=r"(*addr++) : "r"(s++));
	__asm __volatile("eieio; sync");
}

#if 0	/* Cause a link error for bus_space_read_region_8 */
#define	bus_space_read_region_8		!!! unimplemented !!!
#endif

static __inline void
bus_space_read_region_stream_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int16_t *addr, size_t count)
{
	volatile u_int16_t *s = __ppc_ba(tag, bsh, offset);

	while (count--)
		*addr++ = *s++;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_read_region_stream_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int32_t *addr, size_t count)
{
	volatile u_int32_t *s = __ppc_ba(tag, bsh, offset);

	while (count--)
		*addr++ = *s++;
	__asm __volatile("eieio; sync");
}

#if 0	/* Cause a link error */
#define	bus_space_read_region_stream_8		!!! unimplemented !!!
#endif

/*
 *	void bus_space_write_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset,
 *	    u_intN_t value));
 *
 * Write the 1, 2, 4, or 8 byte value `value' to bus space
 * described by tag/handle/offset.
 */

#define bus_space_write_1(t, h, o, v)	out8(__ppc_ba(t, h, o), (v))
#define bus_space_write_2(t, h, o, v)	out16rb(__ppc_ba(t, h, o), (v))
#define bus_space_write_4(t, h, o, v)	out32rb(__ppc_ba(t, h, o), (v))

#define bus_space_write_stream_1(t, h, o, v)	out8(__ppc_ba(t, h, o), (v))
#define bus_space_write_stream_2(t, h, o, v)	out16(__ppc_ba(t, h, o), (v))
#define bus_space_write_stream_4(t, h, o, v)	out32(__ppc_ba(t, h, o), (v))

#if 0	/* Cause a link error for bus_space_write_8 */
#define bus_space_write_8		!!! unimplemented !!!
#endif

/*
 *	void bus_space_write_multi_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset,
 *	    const u_intN_t *addr, size_t count));
 *
 * Write `count' 1, 2, 4, or 8 byte quantities from the buffer
 * provided to bus space described by tag/handle/offset.
 */

#define bus_space_write_multi_1(t, h, o, a, c) do {			\
		outsb(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#define bus_space_write_multi_2(t, h, o, a, c) do {			\
		outsw(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#define bus_space_write_multi_4(t, h, o, a, c) do {			\
		outsl(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#if 0
#define bus_space_write_multi_8		!!! unimplemented !!!
#endif

#define bus_space_write_multi_stream_2(t, h, o, a, c) do {		\
		outsw(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#define bus_space_write_multi_stream_4(t, h, o, a, c) do {		\
		outsl(__ppc_ba(t, h, o), (a), (c));		       	\
	} while (0)

#if 0
#define bus_space_write_multi_stream_8	!!! unimplemented !!!
#endif

/*
 *	void bus_space_write_region_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset,
 *	    const u_intN_t *addr, size_t count));
 *
 * Write `count' 1, 2, 4, or 8 byte quantities from the buffer provided
 * to bus space described by tag/handle starting at `offset'.
 */

static __inline void
bus_space_write_region_1(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, const u_int8_t *addr, size_t count)
{
	volatile u_int8_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d++ = *addr++;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_write_region_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, const u_int16_t *addr, size_t count)
{
	volatile u_int16_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("sthbrx %0, 0, %1" ::
			"r"(*addr++), "r"(d++));
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_write_region_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, const u_int32_t *addr, size_t count)
{
	volatile u_int32_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("stwbrx %0, 0, %1" ::
			"r"(*addr++), "r"(d++));
	__asm __volatile("eieio; sync");
}

#if 0
#define	bus_space_write_region_8 !!! bus_space_write_region_8 unimplemented !!!
#endif

static __inline void
bus_space_write_region_stream_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, const u_int16_t *addr, size_t count)
{
	volatile u_int16_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d++ = *addr++;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_write_region_stream_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, const u_int32_t *addr, size_t count)
{
	volatile u_int32_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d++ = *addr++;
	__asm __volatile("eieio; sync");
}

#if 0
#define	bus_space_write_region_stream_8	!!! unimplemented !!!
#endif

/*
 *	void bus_space_set_multi_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset, u_intN_t val,
 *	    size_t count));
 *
 * Write the 1, 2, 4, or 8 byte value `val' to bus space described
 * by tag/handle/offset `count' times.
 */

static __inline void
bus_space_set_multi_1(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int8_t val, size_t count)
{
	volatile u_int8_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d = val;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_set_multi_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int16_t val, size_t count)
{
	volatile u_int16_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("sthbrx %0, 0, %1" ::
			"r"(val), "r"(d));
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_set_multi_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int32_t val, size_t count)
{
	volatile u_int32_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("stwbrx %0, 0, %1" ::
			"r"(val), "r"(d));
	__asm __volatile("eieio; sync");
}

#if 0
#define	bus_space_set_multi_8 !!! bus_space_set_multi_8 unimplemented !!!
#endif

static __inline void
bus_space_set_multi_stream_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int16_t val, size_t count)
{
	volatile u_int16_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d = val;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_set_multi_stream_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int32_t val, size_t count)
{
	volatile u_int32_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d = val;
	__asm __volatile("eieio; sync");
}

#if 0
#define	bus_space_set_multi_stream_8	!!! unimplemented !!!
#endif

/*
 *	void bus_space_set_region_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset, u_intN_t val,
 *	    size_t count));
 *
 * Write `count' 1, 2, 4, or 8 byte value `val' to bus space described
 * by tag/handle starting at `offset'.
 */

static __inline void
bus_space_set_region_1(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int8_t val, size_t count)
{
	volatile u_int8_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d++ = val;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_set_region_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int16_t val, size_t count)
{
	volatile u_int16_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("sthbrx %0, 0, %1" ::
			"r"(val), "r"(d++));
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_set_region_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int32_t val, size_t count)
{
	volatile u_int32_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		__asm __volatile("stwbrx %0, 0, %1" ::
			"r"(val), "r"(d++));
	__asm __volatile("eieio; sync");
}

#if 0
#define	bus_space_set_region_8 !!! bus_space_set_region_8 unimplemented !!!
#endif

static __inline void
bus_space_set_region_stream_2(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int16_t val, size_t count)
{
	volatile u_int16_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d++ = val;
	__asm __volatile("eieio; sync");
}

static __inline void
bus_space_set_region_stream_4(bus_space_tag_t tag, bus_space_handle_t bsh,
    bus_size_t offset, u_int32_t val, size_t count)
{
	volatile u_int32_t *d = __ppc_ba(tag, bsh, offset);

	while (count--)
		*d++ = val;
	__asm __volatile("eieio; sync");
}

#if 0
#define	bus_space_set_region_stream_8	!!! unimplemented !!!
#endif

/*
 *	void bus_space_copy_region_N(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh1, bus_size_t off1,
 *	    bus_space_handle_t bsh2, bus_size_t off2,
 *	    size_t count));
 *
 * Copy `count' 1, 2, 4, or 8 byte values from bus space starting
 * at tag/bsh1/off1 to bus space starting at tag/bsh2/off2.
 */

	/* XXX IMPLEMENT bus_space_copy_N() XXX */

/*
 * Bus read/write barrier methods.
 *
 *	void bus_space_barrier(bus_space_tag_t tag,
 *	    bus_space_handle_t bsh, bus_size_t offset,
 *	    bus_size_t len, int flags));
 *
 * Note: the macppc does not currently require barriers, but we must
 * provide the flags to MI code.
 */

#define bus_space_barrier(t, h, o, l, f)	\
	((void)((void)(t), (void)(h), (void)(o), (void)(l), (void)(f)))
#define	BUS_SPACE_BARRIER_READ	0x01		/* force read barrier */
#define	BUS_SPACE_BARRIER_WRITE	0x02		/* force write barrier */

#define	BUS_SPACE_ALIGNED_POINTER(p, t) ALIGNED_POINTER(p, t)

/*
 * Bus DMA methods.
 */

/*
 * Flags used in various bus DMA methods.
 */
#define	BUS_DMA_WAITOK		0x00	/* safe to sleep (pseudo-flag) */
#define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
#define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
#define	BUS_DMA_COHERENT	0x04	/* hint: map memory DMA coherent */
#define	BUS_DMA_BUS1		0x10	/* placeholders for bus functions... */
#define	BUS_DMA_BUS2		0x20
#define	BUS_DMA_BUS3		0x40
#define	BUS_DMA_BUS4		0x80

/* Forwards needed by prototypes below. */
struct mbuf;
struct uio;

/*
 *      bus_dmasync_op_t
 *
 *      Operations performed by bus_dmamap_sync().
 */
typedef enum {
	BUS_DMASYNC_PREREAD,
	BUS_DMASYNC_POSTREAD,
	BUS_DMASYNC_PREWRITE,
	BUS_DMASYNC_POSTWRITE
} bus_dmasync_op_t;

/*
 *      bus_dma_tag_t
 *
 *      A machine-dependent opaque type describing the characteristics
 *      of how to perform DMA mappings.  This structure encapsultes
 *      information concerning address and alignment restrictions, number
 *      of S/G  segments, amount of data per S/G segment, etc.
 */
typedef struct bus_dma_tag	*bus_dma_tag_t;

/*
 *      bus_dmamap_t
 *
 *      DMA mapping instance information.
 */
typedef struct bus_dmamap	*bus_dmamap_t;

/*
 *	bus_dma_segment_t
 *
 *	Describes a single contiguous DMA transaction.  Values
 *	are suitable for programming into DMA registers.
 */
typedef struct bus_dma_segment {
	bus_addr_t	ds_addr;	/* DMA address */
	bus_size_t	ds_len;		/* length of transfer */
} bus_dma_segment_t;

/*
 * A function that returns 1 if the address cannot be accessed by
 * a device and 0 if it can be.
 */
typedef int bus_dma_filter_t(void *, bus_addr_t);

/*
 * Allocate a device specific dma_tag encapsulating the constraints of
 * the parent tag in addition to other restrictions specified:
 *
 *      alignment:      alignment for segments.
 *      boundary:       Boundary that segments cannot cross.
 *      lowaddr:        Low restricted address that cannot appear in a mapping.
 *      highaddr:       High restricted address that cannot appear in a mapping.
 *      filtfunc:       An optional function to further test if an address
 *                      within the range of lowaddr and highaddr cannot appear
 *                      in a mapping.
 *      filtfuncarg:    An argument that will be passed to filtfunc in addition
 *                      to the address to test.
 *      maxsize:        Maximum mapping size supported by this tag.
 *      nsegments:      Number of discontinuities allowed in maps.
 *      maxsegsz:       Maximum size of a segment in the map.
 *      flags:          Bus DMA flags.
 *      dmat:           A pointer to set to a valid dma tag should the return
 *                      value of this function indicate success.
 */
int bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
		       bus_size_t boundary, bus_addr_t lowaddr,
		       bus_addr_t highaddr, bus_dma_filter_t *filtfunc,
		       void *filtfuncarg, bus_size_t maxsize, int nsegments,
		       bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat);

int bus_dma_tag_destroy(bus_dma_tag_t dmat);

/*
 * Allocate a handle for mapping from kva/uva/physical
 * address space into bus device space.
 */
int bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp);

/*
 * Destroy  a handle for mapping from kva/uva/physical
 * address space into bus device space.
 */
int bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map);

/*
 * Allocate a piece of memory that can be efficiently mapped into
 * bus device space based on the constraints lited in the dma tag.
 * A dmamap to for use with dmamap_load is also allocated.
 */
int bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
		     bus_dmamap_t *mapp);

/*
 * Free a piece of memory and it's allociated dmamap, that was allocated
 * via bus_dmamem_alloc.
 */
void bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map);

/*
 * A function that processes a successfully loaded dma map or an error
 * from a delayed load map.
 */
typedef void bus_dmamap_callback_t(void *, bus_dma_segment_t *, int, int);

/*
 * Map the buffer buf into bus space using the dmamap map.
 */
int bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
		    bus_size_t buflen, bus_dmamap_callback_t *callback,
		    void *callback_arg, int flags);

/*
 * Perform a syncronization operation on the given map.
 */
void bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t, bus_dmasync_op_t);

/*
 * Release the mapping held by map.
 */
void bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map);

#endif /* _MACPPC_BUS_H_ */