root/sys/arch/mips/include/bus_dma_defs.h
/* $NetBSD: bus_dma_defs.h,v 1.6 2022/01/22 15:10:31 skrll Exp $ */

/*-
 * Copyright (c) 1997, 1998, 2000, 2001 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.
 *
 * 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 _MIPS_BUS_DMA_DEFS_H_
#define _MIPS_BUS_DMA_DEFS_H_

#include <sys/types.h>

#ifdef _KERNEL
/*
 * Bus DMA methods.
 */

/*
 * Flags used in various bus DMA methods.
 */
#define BUS_DMA_WAITOK          0x000   /* safe to sleep (pseudo-flag) */
#define BUS_DMA_NOWAIT          0x001   /* not safe to sleep */
#define BUS_DMA_ALLOCNOW        0x002   /* perform resource allocation now */
#define BUS_DMA_COHERENT        0x004   /* hint: map memory DMA coherent */
#define BUS_DMA_STREAMING       0x008   /* hint: sequential, unidirectional */
#define BUS_DMA_BUS1            0x010   /* placeholders for bus functions... */
#define BUS_DMA_BUS2            0x020
#define BUS_DMA_BUS3            0x040
#define BUS_DMA_BUS4            0x080
#define BUS_DMA_READ            0x100   /* mapping is device -> memory only */
#define BUS_DMA_WRITE           0x200   /* mapping is memory -> device only */
#define BUS_DMA_NOCACHE         0x400   /* hint: map non-cached memory */
#define BUS_DMA_PREFETCHABLE    0x800   /* hint: map non-cached but allow
                                         * things like write combining */

/*
 * Private flags stored in the DMA map.
 */
#define _BUS_DMAMAP_COHERENT    0x10000 /* no cache flush necessary on sync */

/* 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 */

typedef struct mips_bus_dma_tag *bus_dma_tag_t;
typedef struct mips_bus_dmamap  *bus_dmamap_t;

/*
 *      bus_dma_segment_t
 *
 *      Describes a single contiguous DMA transaction.  Values
 *      are suitable for programming into DMA registers.
 */
struct mips_bus_dma_segment {
        bus_addr_t      ds_addr;        /* DMA address */
        bus_size_t      ds_len;         /* length of transfer */
        register_t      _ds_vaddr;      /* virtual address, 0 if invalid */
};
typedef struct mips_bus_dma_segment     bus_dma_segment_t;

/*
 * DMA mapping methods.
 */
struct mips_bus_dmamap_ops {
        int     (*dmamap_create)(bus_dma_tag_t, bus_size_t, int,
                    bus_size_t, bus_size_t, int, bus_dmamap_t *);
        void    (*dmamap_destroy)(bus_dma_tag_t, bus_dmamap_t);
        int     (*dmamap_load)(bus_dma_tag_t, bus_dmamap_t, void *,
                    bus_size_t, struct proc *, int);
        int     (*dmamap_load_mbuf)(bus_dma_tag_t, bus_dmamap_t,
                    struct mbuf *, int);
        int     (*dmamap_load_uio)(bus_dma_tag_t, bus_dmamap_t,
                    struct uio *, int);
        int     (*dmamap_load_raw)(bus_dma_tag_t, bus_dmamap_t,
                    bus_dma_segment_t *, int, bus_size_t, int);
        void    (*dmamap_unload)(bus_dma_tag_t, bus_dmamap_t);
        void    (*dmamap_sync)(bus_dma_tag_t, bus_dmamap_t,
                    bus_addr_t, bus_size_t, int);
};

/*
 * DMA memory utility functions.
 */
struct mips_bus_dmamem_ops {
        int     (*dmamem_alloc)(bus_dma_tag_t, bus_size_t, bus_size_t,
                    bus_size_t, bus_dma_segment_t *, int, int *, int);
        void    (*dmamem_free)(bus_dma_tag_t,
                    bus_dma_segment_t *, int);
        int     (*dmamem_map)(bus_dma_tag_t, bus_dma_segment_t *,
                    int, size_t, void **, int);
        void    (*dmamem_unmap)(bus_dma_tag_t, void *, size_t);
        paddr_t (*dmamem_mmap)(bus_dma_tag_t, bus_dma_segment_t *,
                    int, off_t, int, int);
};

/*
 * DMA tag utility functions.
 */
struct mips_bus_dmatag_ops {
        int     (*dmatag_subregion)(bus_dma_tag_t, bus_addr_t, bus_addr_t,
                    bus_dma_tag_t *, int);
        void    (*dmatag_destroy)(bus_dma_tag_t);
};

/*
 *      bus_dma_tag_t
 *
 *      A machine-dependent opaque type describing the implementation of
 *      DMA for a given bus.
 */
struct mips_bus_dma_tag {
        void    *_cookie;               /* cookie used in the guts */

        bus_addr_t _wbase;              /* DMA window base */
        int _tag_needs_free;            /* number of references (maybe 0) */
        bus_addr_t _bounce_thresh;
        bus_addr_t _bounce_alloc_lo;    /* physical base of the window */
        bus_addr_t _bounce_alloc_hi;    /* physical limit of the windows */
        int     (*_may_bounce)(bus_dma_tag_t, bus_dmamap_t, int, int *);

        struct mips_bus_dmamap_ops _dmamap_ops;
        struct mips_bus_dmamem_ops _dmamem_ops;
        struct mips_bus_dmatag_ops _dmatag_ops;
};

/*
 *      bus_dmamap_t
 *
 *      Describes a DMA mapping.
 */
struct mips_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_maxmaxsegsz; /* fixed largest possible segment */
        bus_size_t      _dm_boundary;   /* don't cross this */
        bus_addr_t      _dm_bounce_thresh; /* bounce threshold; see tag */
        int             _dm_flags;      /* misc. flags */
        struct vmspace  *_dm_vmspace;   /* vmspace that owns the mapping */

        /*
         * Private cookie to be used by the DMA back-end.
         */
        void            *_dm_cookie;

        /*
         * PUBLIC MEMBERS: these are used by machine-independent code.
         */
        bus_size_t      dm_maxsegsz;    /* largest possible segment */
        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 _MIPS_BUS_DMA_PRIVATE
#define _BUS_AVAIL_END  (pmap_limits.avail_end - 1)
/*
 * Cookie used for bounce buffers. A pointer to one of these it stashed in
 * the DMA map.
 */
struct mips_bus_dma_cookie {
        int     id_flags;               /* flags; see below */

        /*
         * Information about the original buffer used during
         * DMA map syncs.  Note that origibuflen is only used
         * for ID_BUFTYPE_LINEAR.
         */
        union {
                void    *un_origbuf;            /* pointer to orig buffer if
                                                   bouncing */
                char    *un_linearbuf;
                struct mbuf     *un_mbuf;
                struct uio      *un_uio;
        } id_origbuf_un;
#define id_origbuf              id_origbuf_un.un_origbuf
#define id_origlinearbuf        id_origbuf_un.un_linearbuf
#define id_origmbuf             id_origbuf_un.un_mbuf
#define id_origuio              id_origbuf_un.un_uio
        bus_size_t id_origbuflen;       /* ...and size */
        int     id_buftype;             /* type of buffer */

        void    *id_bouncebuf;          /* pointer to the bounce buffer */
        bus_size_t id_bouncebuflen;     /* ...and size */
        int     id_nbouncesegs;         /* number of valid bounce segs */
        bus_dma_segment_t id_bouncesegs[0]; /* array of bounce buffer
                                               physical memory segments */
};

/* id_flags */
#endif /* _MIPS_BUS_DMA_PRIVATE */
#define _BUS_DMA_MIGHT_NEED_BOUNCE      0x01    /* may need bounce buffers */
#ifdef _MIPS_BUS_DMA_PRIVATE
#define _BUS_DMA_HAS_BOUNCE             0x02    /* has bounce buffers */
#define _BUS_DMA_IS_BOUNCING            0x04    /* is bouncing current xfer */

/* id_buftype */
#define _BUS_DMA_BUFTYPE_INVALID        0
#define _BUS_DMA_BUFTYPE_LINEAR         1
#define _BUS_DMA_BUFTYPE_MBUF           2
#define _BUS_DMA_BUFTYPE_UIO            3
#define _BUS_DMA_BUFTYPE_RAW            4

extern const struct mips_bus_dmamap_ops mips_bus_dmamap_ops;
extern const struct mips_bus_dmamem_ops mips_bus_dmamem_ops;
extern const struct mips_bus_dmatag_ops mips_bus_dmatag_ops;

#define _BUS_DMAMAP_OPS_INITIALIZER {                                   \
                .dmamap_create          = _bus_dmamap_create,           \
                .dmamap_destroy         = _bus_dmamap_destroy,          \
                .dmamap_load            = _bus_dmamap_load,             \
                .dmamap_load_mbuf       = _bus_dmamap_load_mbuf,        \
                .dmamap_load_uio        = _bus_dmamap_load_uio,         \
                .dmamap_load_raw        = _bus_dmamap_load_raw,         \
                .dmamap_unload          = _bus_dmamap_unload,           \
                .dmamap_sync            = _bus_dmamap_sync,             \
        }

#define _BUS_DMAMEM_OPS_INITIALIZER {                                   \
                .dmamem_alloc =         _bus_dmamem_alloc,              \
                .dmamem_free =          _bus_dmamem_free,               \
                .dmamem_map =           _bus_dmamem_map,                \
                .dmamem_unmap =         _bus_dmamem_unmap,              \
                .dmamem_mmap =          _bus_dmamem_mmap,               \
        }

#define _BUS_DMATAG_OPS_INITIALIZER {                                   \
                .dmatag_subregion =     _bus_dmatag_subregion,          \
                .dmatag_destroy =       _bus_dmatag_destroy,            \
        }
#endif /* _MIPS_BUS_DMA_PRIVATE */

#endif /* _KERNEL */

#endif /* _MIPS_BUS_DMA_DEFS_H_ */