1/*	$NetBSD: rbus.h,v 1.10 2007/10/19 11:59:40 ad Exp $	*/
2
3/*
4 * Copyright (c) 1999
5 *     HAYAKAWA Koichi.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef _DEV_CARDBUS_RBUS_H_
30#define _DEV_CARDBUS_RBUS_H_
31
32/*
33 * This file defines the rbus (pseudo) class
34 *
35 * What is rbus?
36 *
37 *  The rbus is a recursive bus-space administrator.  This means a
38 *  parent bus-space administrator, which usually belongs to a bus
39 *  bridge, makes some child bus-space administrators and gives
40 *  (restricted) bus-space to the children.  There is a root bus-space
41 *  administrator which maintains the whole bus-space.
42 *
43 * Why recursive?
44 *
45 *  The recursive bus-space administration has two virtues.  The
46 *  former is this modelling matches the actual memory and io space
47 *  management of bridge devices well.  The latter is that the rbus is a
48 *  distributed management system, so it matches well with a
49 *  multi-thread kernel.
50 *
51 * Abstraction
52 *
53 *  The rbus models bus-to-bus bridges into three types: dedicated, shared,
54 *  and slave.  Dedicated means that the bridge has dedicated bus space.
55 *  Shared means that the bridge has bus space, but this bus space is
56 *  shared with other bus bridges.  Slave means a bus bridge which
57 *  does not have it own bus space and asks a parent bus bridge for bus
58 *  space when a client requests bus space from the bridge.
59 */
60
61
62/* require sys/extent.h */
63/* require sys/bus.h */
64
65#define rbus 1
66
67
68struct extent;
69
70
71/*
72 *     General rule
73 *
74 * 1) When a rbustag has no space for child (it means rb_extent is
75 *    NULL), ask bus-space for parent through rb_parent.
76 *
77 * 2) When a rbustag has its own space (whether shared or dedicated),
78 *    allocate from rb_ext.
79 */
80struct rbustag {
81  bus_space_tag_t rb_bt;
82  struct rbustag *rb_parent;
83  struct extent *rb_ext;
84  bus_addr_t rb_start;
85  bus_addr_t rb_end;
86  bus_addr_t rb_offset;
87#if notyet
88  int (*rb_space_alloc)(struct rbustag *, bus_addr_t, bus_addr_t,
89			     bus_addr_t, bus_size_t, bus_addr_t, bus_addr_t,
90			     int, bus_addr_t *, bus_space_handle_t *);
91  int (*rbus_space_free)(struct rbustag *, bus_space_handle_t,
92			      bus_size_t, bus_addr_t *);
93#endif
94  int rb_flags;
95#define RBUS_SPACE_INVALID   0x00
96#define RBUS_SPACE_SHARE     0x01
97#define RBUS_SPACE_DEDICATE  0x02
98#define RBUS_SPACE_MASK      0x03
99#define RBUS_SPACE_ASK_PARENT 0x04
100  /* your own data below */
101  void *rb_md;
102};
103
104typedef struct rbustag *rbus_tag_t;
105
106
107
108
109/*
110 * These functions sugarcoat rbus interface to make rbus being used
111 * easier.  These functions should be member functions of rbus
112 * `class'.
113 */
114int rbus_space_alloc(rbus_tag_t, bus_addr_t, bus_size_t, bus_addr_t,
115    bus_addr_t, int, bus_addr_t *, bus_space_handle_t *);
116
117int rbus_space_alloc_subregion(rbus_tag_t, bus_addr_t, bus_addr_t,
118    bus_addr_t, bus_size_t, bus_addr_t, bus_addr_t, int,
119    bus_addr_t *, bus_space_handle_t *);
120
121int rbus_space_free(rbus_tag_t, bus_space_handle_t, bus_size_t,
122    bus_addr_t *);
123
124
125/*
126 * These functions create rbus instance.  These functions are
127 * so-called-as a constructor of rbus.
128 *
129 * rbus_new is a constructor which make an rbus instance from a parent
130 * rbus.
131 */
132rbus_tag_t rbus_new(rbus_tag_t, bus_addr_t, bus_size_t, bus_addr_t, int);
133
134rbus_tag_t rbus_new_root_delegate(bus_space_tag_t, bus_addr_t, bus_size_t,
135    bus_addr_t);
136rbus_tag_t rbus_new_root_share(bus_space_tag_t, struct extent *,
137    bus_addr_t, bus_size_t, bus_addr_t);
138
139/*
140 * This function release bus-space used by the argument.  This
141 * function is so-called-as a destructor.
142 */
143int rbus_delete(rbus_tag_t);
144
145
146/*
147 * Machine-dependent definitions.
148 */
149#include <machine/rbus_machdep.h>
150
151#endif /* !_DEV_CARDBUS_RBUS_H_ */
152