freebsd-skq/sys/amd64/include/bus_dma.h
Hiten Pandya b77c32a07e Rename BUS_DMAMEM_NOSYNC to BUS_DMA_COHERENT.
The current name is confusing, because it indicates to
the client that a bus_dmamap_sync() operation is not
necessary when the flag is specified, which is wrong.

The main purpose of this flag is to hint the underlying
architecture that DMA memory should be mapped in a coherent
way, but the architecture can ignore it.  But if the
architecture does supports coherent mapping of memory, then
it makes bus_dmamap_sync() calls cheap.

This flag is the same as the one in NetBSD's Bus DMA.

Reviewed by: gibbs, scottl, des (implicitly)
Approved by: re@ (jhb)
2003-05-30 20:40:33 +00:00

242 lines
9.2 KiB
C

/* $NetBSD: bus.h,v 1.12 1997/10/01 08:25:15 fvdl Exp $ */
/*-
* Copyright (c) 1996, 1997 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.
*/
/* $FreeBSD$ */
#ifndef _AMD64_BUS_DMA_H_
#define _AMD64_BUS_DMA_H_
/*
* 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 in a coherent way */
#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;
/*
* Operations performed by bus_dmamap_sync().
*/
typedef int bus_dmasync_op_t;
#define BUS_DMASYNC_PREREAD 1
#define BUS_DMASYNC_POSTREAD 2
#define BUS_DMASYNC_PREWRITE 4
#define BUS_DMASYNC_POSTWRITE 8
/*
* 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.
*/
/* XXX Should probably allow specification of alignment */
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);
/*
* Like bus_dmamap_callback but includes map size in bytes. This is
* defined as a separate interface to maintain compatiiblity for users
* of bus_dmamap_callback_t--at some point these interfaces should be merged.
*/
typedef void bus_dmamap_callback2_t(void *, bus_dma_segment_t *, int, bus_size_t, int);
/*
* Like bus_dmamap_load but for mbufs. Note the use of the
* bus_dmamap_callback2_t interface.
*/
int bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
struct mbuf *mbuf,
bus_dmamap_callback2_t *callback, void *callback_arg,
int flags);
/*
* Like bus_dmamap_load but for uios. Note the use of the
* bus_dmamap_callback2_t interface.
*/
int bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
struct uio *ui,
bus_dmamap_callback2_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);
#define bus_dmamap_sync(dmat, dmamap, op) \
if ((dmamap) != NULL) \
_bus_dmamap_sync(dmat, dmamap, op)
/*
* Release the mapping held by map.
*/
void _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map);
#define bus_dmamap_unload(dmat, dmamap) \
if ((dmamap) != NULL) \
_bus_dmamap_unload(dmat, dmamap)
#endif /* _AMD64_BUS_DMA_H_ */