1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
.\" -*- nroff -*-
.\"
.\" Copyright (c) 2000 Alexander Langer
.\"
.\" All rights reserved.
.\"
.\" This program is free software.
.\"
.\" 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 DEVELOPERS ``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 DEVELOPERS 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.
.\"
.\" $FreeBSD$
.\"
.Dd May 18, 2000
.Dt BUS_ALLOC_RESOURCE 9
.Os FreeBSD
.Sh NAME
.Nm bus_alloc_resource
.Nd alloc resources on a bus
.Sh SYNOPSIS
.Fd #include <sys/param.h>
.Fd #include <sys/bus.h>
.Fd #include <sys/rman.h>
.Fd #include <sys/resource.h>
.Ft struct resource *
.Fn bus_alloc_resource "device_t dev" "int type" "int *rid" "u_long start" "u_long end" "u_long count" "u_int flags"
.Sh DESCRIPTION
.Pp
This is an easy interface to the resource-management functions.
It hides the indirection through the parent's method table.
This function generally should be called in attach, but (except in some
race cases) never earlier.
.Pp
Its arguments are as follows:
.Bl -item
.It
.Fa dev
is the device that requests ownership of the resource.
Before allocation, the resource is owned by the parent bus.
.It
.Fa type
is the type of resource you want to allocate.
It is one of:
.Bl -tag -width SYS_RES_MEMORY
.It Dv SYS_RES_IRQ
for IRQs
.It Dv SYS_RES_DRQ
for ISA DMA lines
.It Dv SYS_RES_IOPORT
for I/O ports
.It Dv SYS_RES_MEMORY
for I/O memory
.El
.It
.Fa rid
points to a bus specific handle that identifies the resource being allocated.
For ISA this is an index into an array of resources that have been setup
for this device by either the PnP mechanism, or via the hints mechanism.
For PCCARD, similar things are used as of writing,
but that may change in the future with newcard.
For PCI it just happens to be the offset into pci config space which has
a word that describes the resource.
The bus methods are free to change the RIDs that they are given as a parameter.
You must not depend on the value you gave it earlier.
.It
.Fa start
and
.Fa end
are the start/end addresses of the resource.
If you specify values of
.Dv 0
for start and
.Dv ~0
for end, the default values for the bus are calculated.
.It
.Fa count
is the size of the resource, e.g. the size of an I/O port (often
.Dv 1
on PCI and device-dependent on ISA and PCCARD).
If you specified the default values for
.Fa start
and
.Fa end ,
then the default value of the bus is used if
.Fa count
is smaller than the default value and
.Fa count
is used, if it is bigger as the default value.
.It
.Fa flags
sets the flags for the resource.
You can set one or more of these flags:
.Bl -tag -width RF_SHAREABLE
.It Dv RF_ALLOCATED
resource has been reserved.
The resource still needs to be activated with
.Xr rman_activate_resource 9 .
.It Dv RF_ACTIVE
activate resource atomically.
.It Dv RF_SHAREABLE
resource permits contemporaneous sharing.
Should always be set unless you know, that the resource cannot be shared.
It is the bus-code's task to filter out the flag if the bus doesn't
support sharing, which is, for example, the case for pccard/cardbus,
which can or can not share devices, depending on the bus.
.It Dv RF_TIMESHARE
resource permits time-division sharing.
.El
.El
.Sh RETURN VALUES
A pointer to
.Va struct res
is returned on success, a null pointer otherwise.
.Sh EXAMPLES
This is some example code.
The values of
.Va portid
and
.Va irqid
should be saved in the softc of the device after these calls.
.Bd -literal
struct resource *portres, irqres;
int portid, irqid;
portid = 0;
irqid = 0;
portres = bus_alloc_resource(dev, SYS_RES_IOPORT, &portid,
0ul, ~0ul, 32, RF_ACTIVE);
irqres = bus_alloc_resource(dev, SYS_RES_IRQ, &irqid,
0ul, ~0ul, 1, RF_ACTIVE | RF_SHAREABLE);
.Ed
.Sh SEE ALSO
.Xr driver 9 ,
.Xr device 9 ,
.Xr bus_release_resource 9
.Sh AUTHORS
This man page was written by
.An Alexander Langer Aq alex@big.endian.de
with parts by
.An Warner Losh Aq imp@FreeBSD.ORG .
|
