summaryrefslogtreecommitdiff
path: root/share/man/man9/pci_intr_map.9
blob: 496f56a9f4855fa431f3ffb377f427e499dde936 (plain)
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
.\"	$OpenBSD: pci_intr_map.9,v 1.12 2011/05/22 06:20:46 jmc Exp $
.\"
.\" Copyright (c) 2005 Michael Shalayeff
.\" All rights reserved.
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: May 22 2011 $
.Dt PCI_INTR_MAP 9
.Os
.Sh NAME
.Nm pci_intr_map ,
.Nm pci_intr_map_msi ,
.Nm pci_intr_line ,
.Nm pci_intr_string ,
.Nm pci_intr_establish ,
.Nm pci_intr_disestablish
.Nd PCI interrupts
.Sh SYNOPSIS
.Fd #include <alpha/pci/pci_machdep.h>
.Fd #include <i386/pci/pci_machdep.h>
.Fd #include <powerpc/pci/pci_machdep.h>
.Fd #include <sgi/pci/pci_machdep.h>
.Fd #include <machine/pci_machdep.h>
.Ft int
.Fn pci_intr_map "struct pci_attach_args *paa" "pci_intr_handle_t *ih"
.Ft int
.Fn pci_intr_map_msi "struct pci_attach_args *paa" "pci_intr_handle_t *ih"
.Ft int
.Fn pci_intr_line "pci_intr_handle_t ih"
.Ft const char *
.Fn pci_intr_string "pci_chipset_tag_t pc" "pci_intr_handle_t ih"
.Ft void *
.Fn pci_intr_establish "pci_chipset_tag_t pc" "pci_intr_handle_t ih" \
"int level" "int (*func)(void *)" "void *arg" "const char *name"
.Ft void
.Fn pci_intr_disestablish "pci_chipset_tag_t pc" "void *v"
.Sh DESCRIPTION
These functions are provided by the machine-dependent implementation
for attaching handler functions to the interrupts of PCI devices.
.Pp
An architect type is provided by the machine-dependent
code
.Va pci_intr_handle_t ,
to be initialised by
.Fn pci_intr_map
or
.Fn pci_intr_map_msi .
.Pp
The
.Fn pci_intr_map
function should be called first to establish a mapping between a PCI
pin and the interrupt controller's interrupt vector.
This process may include resolving the mapping through
firmware-provided information.
For devices that support Message Signaled Interrupts (MSI) the
.Fn pci_intr_map_msi
function should be called instead.
This function can fail if the
system does not support MSI.
In that case
.Fn pci_intr_map
should be called to fall back on classic PCI interrupts.
.Pp
Having initialised the
.Va pci_intr_handle_t
in the previous step, an interrupt handler can be established using
.Fn pci_intr_establish
or converted into printable form using
.Fn pci_intr_string .
A handler established using
.Fn pci_intr_establish
is always called with the system interrupt priority level set equal to,
or higher than,
.Va level .
.Pp
.Fn pci_intr_line
provides the interrupt line extracted from the MD interrupt handle.
Upon device detachment,
.Fn pci_intr_disestablish
should be used to disassociate the handler from the interrupt.
.Pp
See
.Xr spl 9
for an explanation of the
.Va ipl
.Dq interrupt priority levels .
.Sh EXAMPLES
A typical code sequence for establishing a handler
for a device interrupt in the driver might be:
.Bd -literal -offset 3n
int
xxxattach(struct device *parent, struct device *self, void *aux)
{
	struct xxx_softc *sc = (struct xxx_softc *)self;
	struct pci_attach_args *pa = aux;
	pci_intr_handle_t ih;
	const char *intrstr;
	bus_size_t size;

	\&...

	if (pci_intr_map_msi(pa, &ih) && pci_intr_map(pa, &ih)) {
		printf(": can't map interrupt\en");
		bus_space_unmap(sc->iot, sc->ioh, size);
		return;
	}
	intrstr = pci_intr_string(pa->pa_pc, ih);
	sc->sc_ih = pci_intr_establish(pa->pa_pc, ih, IPL_NET,
	    xxx_intr, sc, sc->sc_dev.dv_xname);
	if (!sc->sc_ih) {
		printf(": can't establish interrupt");
		if (intrstr)
			printf(" at %s", intrstr);
		printf("\en");
		bus_space_unmap(sc->iot, sc->ioh, size);
		return;
	}

	printf(": %s\en", intrstr);

	\&...
}
.Ed
.Sh SEE ALSO
.Xr cardbus 4 ,
.Xr pci 4 ,
.Xr pcibios 4 ,
.Xr pci_conf_read 9 ,
.Xr spl 9
.Sh HISTORY
These functions first appeared in
.Ox 1.2 .
.\" .Sh AUTHORS