text: /* $NetBSD: bus_dma.h,v 1.1.1.1 1998/06/09 07:53:05 dbj Exp $ */
  
  /*-
   * Copyright (c) 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 Carnegie-Mellon University.
   * All rights reserved.
   *
   * Author: Chris G. Demetriou
   *
   * Permission to use, copy, modify and distribute this software and
   * its documentation is hereby granted, provided that both the copyright
   * notice and this permission notice appear in all copies of the
   * software, derivative works or modified versions, and any portions
   * thereof, and that both notices appear in supporting documentation.
   *
   * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
   * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
   * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
   *
   * Carnegie Mellon requests users of this software to return to
   *
   *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
   *  School of Computer Science
   *  Carnegie Mellon University
   *  Pittsburgh PA 15213-3890
   *
   * any improvements or extensions that they make and grant Carnegie the
   * rights to redistribute these changes.
   */
  
  #ifndef _BUS_DMA_H_
  #define	_BUS_DMA_H_
  
  /*
   * 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
  
  /*
   * Private flags stored in the DMA map.
   */
  #define	DMAMAP_HAS_SGMAP	0x80000000	/* sgva/len are valid */
  
  /* Forwards needed by prototypes below. */
  struct mbuf;
  struct uio;
  
  /*
   * Operations performed by bus_dmamap_sync().
   */
  #define	BUS_DMASYNC_PREREAD	0x01	/* pre-read synchronization */
  #define	BUS_DMASYNC_POSTREAD	0x02	/* post-read synchronization */
  #define	BUS_DMASYNC_PREWRITE	0x04	/* pre-write synchronization */
  #define	BUS_DMASYNC_POSTWRITE	0x08	/* post-write synchronization */
  
  /*
   *	generic_bus_t
   *
   *	Busses supported by NetBSD/generic, used by internal
   *	utility functions.  NOT TO BE USED BY MACHINE-INDEPENDENT
   *	CODE!
   */
  typedef enum {
  	GENERIC_BUS_UNKNOWN,
  } generic_bus_t;
  
  typedef struct generic_bus_dma_tag	*bus_dma_tag_t;
  typedef struct generic_bus_dmamap		*bus_dmamap_t;
  
  /*
   *	bus_dma_segment_t
   *
   *	Describes a single contiguous DMA transaction.  Values
   *	are suitable for programming into DMA registers.
   */
  struct generic_bus_dma_segment {
  	bus_addr_t	ds_addr;	/* DMA address */
  	bus_size_t	ds_len;		/* length of transfer */
  };
  typedef struct generic_bus_dma_segment	bus_dma_segment_t;
  
  /*
   *	bus_dma_tag_t
   *
   *	A machine-dependent opaque type describing the implementation of
   *	DMA for a given bus.
   */
  struct generic_bus_dma_tag {
  	void	*_cookie;		/* cookie used in the guts */
  
  	/*
  	 * Internal-use only utility methods.  NOT TO BE USED BY
  	 * MACHINE-INDEPENDENT CODE!
  	 */
  	bus_dma_tag_t (*_get_tag) __P((bus_dma_tag_t, generic_bus_t));
  
  	/*
  	 * DMA mapping methods.
  	 */
  	int	(*_dmamap_create) __P((bus_dma_tag_t, bus_size_t, int,
  		    bus_size_t, bus_size_t, int, bus_dmamap_t *));
  	void	(*_dmamap_destroy) __P((bus_dma_tag_t, bus_dmamap_t));
  	int	(*_dmamap_load) __P((bus_dma_tag_t, bus_dmamap_t, void *,
  		    bus_size_t, struct proc *, int));
  	int	(*_dmamap_load_mbuf) __P((bus_dma_tag_t, bus_dmamap_t,
  		    struct mbuf *, int));
  	int	(*_dmamap_load_uio) __P((bus_dma_tag_t, bus_dmamap_t,
  		    struct uio *, int));
  	int	(*_dmamap_load_raw) __P((bus_dma_tag_t, bus_dmamap_t,
  		    bus_dma_segment_t *, int, bus_size_t, int));
  	void	(*_dmamap_unload) __P((bus_dma_tag_t, bus_dmamap_t));
  	void	(*_dmamap_sync) __P((bus_dma_tag_t, bus_dmamap_t,
  		    bus_addr_t, bus_size_t, int));
  
  	/*
  	 * DMA memory utility functions.
  	 */
  	int	(*_dmamem_alloc) __P((bus_dma_tag_t, bus_size_t, bus_size_t,
  		    bus_size_t, bus_dma_segment_t *, int, int *, int));
  	void	(*_dmamem_free) __P((bus_dma_tag_t,
  		    bus_dma_segment_t *, int));
  	int	(*_dmamem_map) __P((bus_dma_tag_t, bus_dma_segment_t *,
  		    int, size_t, caddr_t *, int));
  	void	(*_dmamem_unmap) __P((bus_dma_tag_t, caddr_t, size_t));
  	int	(*_dmamem_mmap) __P((bus_dma_tag_t, bus_dma_segment_t *,
  		    int, int, int, int));
  };
  
  #define	genericbus_dma_get_tag(t, b)				\
  	(*(t)->_get_tag)(t, b)
  
  #define	bus_dmamap_create(t, s, n, m, b, f, p)			\
  	(*(t)->_dmamap_create)((t), (s), (n), (m), (b), (f), (p))
  #define	bus_dmamap_destroy(t, p)				\
  	(*(t)->_dmamap_destroy)((t), (p))
  #define	bus_dmamap_load(t, m, b, s, p, f)			\
  	(*(t)->_dmamap_load)((t), (m), (b), (s), (p), (f))
  #define	bus_dmamap_load_mbuf(t, m, b, f)			\
  	(*(t)->_dmamap_load_mbuf)((t), (m), (b), (f))
  #define	bus_dmamap_load_uio(t, m, u, f)				\
  	(*(t)->_dmamap_load_uio)((t), (m), (u), (f))
  #define	bus_dmamap_load_raw(t, m, sg, n, s, f)			\
  	(*(t)->_dmamap_load_raw)((t), (m), (sg), (n), (s), (f))
  #define	bus_dmamap_unload(t, p)					\
  	(*(t)->_dmamap_unload)((t), (p))
  #define	bus_dmamap_sync(t, p, o, l, ops)			\
  	(*(t)->_dmamap_sync)((t), (p), (o), (l), (ops))
  #define	bus_dmamem_alloc(t, s, a, b, sg, n, r, f)		\
  	(*(t)->_dmamem_alloc)((t), (s), (a), (b), (sg), (n), (r), (f))
  #define	bus_dmamem_free(t, sg, n)				\
  	(*(t)->_dmamem_free)((t), (sg), (n))
  #define	bus_dmamem_map(t, sg, n, s, k, f)			\
  	(*(t)->_dmamem_map)((t), (sg), (n), (s), (k), (f))
  #define	bus_dmamem_unmap(t, k, s)				\
  	(*(t)->_dmamem_unmap)((t), (k), (s))
  #define	bus_dmamem_mmap(t, sg, n, o, p, f)			\
  	(*(t)->_dmamem_mmap)((t), (sg), (n), (o), (p), (f))
  
  /*
   *	bus_dmamap_t
   *
   *	Describes a DMA mapping.
   */
  struct generic_bus_dmamap {
  	/*
  	 * PRIVATE MEMBERS: not for use my machine-independent code.
  	 */
  	bus_size_t	_dm_size;	/* largest DMA transfer mappable */
  	int		_dm_segcnt;	/* number of segs this map can map */
  	bus_size_t	_dm_maxsegsz;	/* largest possible segment */
  	bus_size_t	_dm_boundary;	/* don't cross this */
  	int		_dm_flags;	/* misc. flags */
  
  #if 0                           /* useful on alpha, but not here */
  
  	/*
  	 * This is used only for SGMAP-mapped DMA, but we keep it
  	 * here to avoid pointless indirection.
  	 */
  	int		_dm_pteidx;	/* PTE index */
  	int		_dm_ptecnt;	/* PTE count */
  	u_long		_dm_sgva;	/* allocated sgva */
  	bus_size_t	_dm_sgvalen;	/* svga length */
  #endif
  
  	/*
  	 * PUBLIC MEMBERS: these are used by machine-independent code.
  	 */
  	bus_size_t	dm_mapsize;	/* size of the mapping */
  	int		dm_nsegs;	/* # valid segments in mapping */
  	bus_dma_segment_t dm_segs[1];	/* segments; variable length */
  };
  
  #ifdef _GENERIC_BUS_DMA_PRIVATE
  int	_bus_dmamap_create __P((bus_dma_tag_t, bus_size_t, int, bus_size_t,
  	    bus_size_t, int, bus_dmamap_t *));
  void	_bus_dmamap_destroy __P((bus_dma_tag_t, bus_dmamap_t));
  
  int	_bus_dmamap_load_direct __P((bus_dma_tag_t, bus_dmamap_t,
  	    void *, bus_size_t, struct proc *, int));
  int	_bus_dmamap_load_mbuf_direct __P((bus_dma_tag_t,
  	    bus_dmamap_t, struct mbuf *, int));
  int	_bus_dmamap_load_uio_direct __P((bus_dma_tag_t,
  	    bus_dmamap_t, struct uio *, int));
  int	_bus_dmamap_load_raw_direct __P((bus_dma_tag_t,
  	    bus_dmamap_t, bus_dma_segment_t *, int, bus_size_t,
  	    int));
  
  void	_bus_dmamap_unload __P((bus_dma_tag_t, bus_dmamap_t));
  void	_bus_dmamap_sync __P((bus_dma_tag_t, bus_dmamap_t, bus_addr_t,
  	    bus_size_t, int));
  
  int	_bus_dmamem_alloc __P((bus_dma_tag_t tag, bus_size_t size,
  	    bus_size_t alignment, bus_size_t boundary,
  	    bus_dma_segment_t *segs, int nsegs, int *rsegs, int flags));
  void	_bus_dmamem_free __P((bus_dma_tag_t tag, bus_dma_segment_t *segs,
  	    int nsegs));
  int	_bus_dmamem_map __P((bus_dma_tag_t tag, bus_dma_segment_t *segs,
  	    int nsegs, size_t size, caddr_t *kvap, int flags));
  void	_bus_dmamem_unmap __P((bus_dma_tag_t tag, caddr_t kva,
  	    size_t size));
  int	_bus_dmamem_mmap __P((bus_dma_tag_t tag, bus_dma_segment_t *segs,
  	    int nsegs, int off, int prot, int flags));
  #endif /* _GENERIC_BUS_DMA_PRIVATE */
  
  #endif /* _BUS_DMA_H_ */
  