xref: /netbsd-src/sys/arch/alpha/common/sgmapvar.h (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /* $NetBSD: sgmapvar.h,v 1.2 1997/06/07 05:29:33 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 1997 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9  * NASA Ames Research Center.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the NetBSD
22  *	Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 #include <sys/extent.h>
41 #include <machine/bus.h>
42 
43 /*
44  * Bits n:13 of the DMA address are the index of the PTE into
45  * the SGMAP page table.
46  */
47 #define	SGMAP_ADDR_PTEIDX_SHIFT	13
48 
49 /*
50  * An Alpha SGMAP's state information.
51  */
52 struct alpha_sgmap {
53 	struct extent *aps_ex;		/* extent map to manage sgva space */
54 	void	*aps_pt;		/* page table */
55 	bus_addr_t aps_ptpa;		/* page table physical address */
56 	bus_addr_t aps_sgvabase;	/* base of the sgva space */
57 	bus_size_t aps_sgvasize;	/* size of the sgva space */
58 	bus_addr_t aps_wbase;		/* base of the dma window */
59 };
60 
61 /*
62  * Cookie used to store SGMAP state for a DMA mapping.  We
63  * could compute some of this at unload time, but storing it
64  * is convenient.
65  */
66 struct alpha_sgmap_cookie {
67 	int	apdc_pteidx;		/* PTE index */
68 	int	apdc_ptecnt;		/* PTE count */
69 	u_long	apdc_sgva;		/* allocated sgva */
70 	bus_size_t apdc_len;		/* sgva size */
71 	int	apdc_flags;
72 };
73 
74 /* apdc_flags */
75 #define	APDC_HAS_SGMAP		0x01	/* sgva/len are valid */
76 
77 void	alpha_sgmap_init __P((bus_dma_tag_t, struct alpha_sgmap *,
78 	    const char *, bus_addr_t, bus_addr_t, bus_size_t, size_t, void *));
79 
80 int	alpha_sgmap_alloc __P((bus_dmamap_t, bus_size_t,
81 	    struct alpha_sgmap *, int));
82 void	alpha_sgmap_free __P((struct alpha_sgmap *,
83 	    struct alpha_sgmap_cookie *));
84