xref: /freebsd/sys/amd64/vmm/amd/amdiommu.c (revision 315ee00f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2021 The FreeBSD Foundation
5  *
6  * Portions of this software were developed by Ka Ho Ng
7  * under sponsorship from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice unmodified, this list of conditions, and the following
14  *    disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/rman.h>
37 
38 #include <dev/pci/pcireg.h>
39 #include <dev/pci/pcivar.h>
40 
41 #include "amdvi_priv.h"
42 #include "ivhd_if.h"
43 
44 struct amdiommu_softc {
45 	struct resource *event_res;	/* Event interrupt resource. */
46 	void   		*event_tag;	/* Event interrupt tag. */
47 	int		event_rid;
48 };
49 
50 static int	amdiommu_probe(device_t);
51 static int	amdiommu_attach(device_t);
52 static int	amdiommu_detach(device_t);
53 static int	ivhd_setup_intr(device_t, driver_intr_t, void *,
54 		    const char *);
55 static int	ivhd_teardown_intr(device_t);
56 
57 static device_method_t amdiommu_methods[] = {
58 	/* device interface */
59 	DEVMETHOD(device_probe,			amdiommu_probe),
60 	DEVMETHOD(device_attach,		amdiommu_attach),
61 	DEVMETHOD(device_detach,		amdiommu_detach),
62 	DEVMETHOD(ivhd_setup_intr,		ivhd_setup_intr),
63 	DEVMETHOD(ivhd_teardown_intr,		ivhd_teardown_intr),
64 	DEVMETHOD_END
65 };
66 static driver_t amdiommu_driver = {
67 	"amdiommu",
68 	amdiommu_methods,
69 	sizeof(struct amdiommu_softc),
70 };
71 
72 static int
73 amdiommu_probe(device_t dev)
74 {
75 	int error;
76 	int capoff;
77 
78 	/*
79 	 * Check base class and sub-class
80 	 */
81 	if (pci_get_class(dev) != PCIC_BASEPERIPH ||
82 	    pci_get_subclass(dev) != PCIS_BASEPERIPH_IOMMU)
83 		return (ENXIO);
84 
85 	/*
86 	 * A IOMMU capability block carries a 0Fh capid.
87 	 */
88 	error = pci_find_cap(dev, PCIY_SECDEV, &capoff);
89 	if (error)
90 		return (ENXIO);
91 
92 	/*
93 	 * bit [18:16] == 011b indicates the capability block is IOMMU
94 	 * capability block. If the field is not set to 011b, bail out.
95 	 */
96 	if ((pci_read_config(dev, capoff + 2, 2) & 0x7) != 0x3)
97 		return (ENXIO);
98 
99 	return (BUS_PROBE_SPECIFIC);
100 }
101 
102 static int
103 amdiommu_attach(device_t dev)
104 {
105 
106 	device_set_desc(dev, "AMD-Vi/IOMMU PCI function");
107 	return (0);
108 }
109 
110 static int
111 amdiommu_detach(device_t dev)
112 {
113 
114 	return (0);
115 }
116 
117 static int
118 ivhd_setup_intr(device_t dev, driver_intr_t handler, void *arg,
119     const char *desc)
120 {
121 	struct amdiommu_softc *sc;
122 	int error, msicnt;
123 
124 	sc = device_get_softc(dev);
125 	msicnt = 1;
126 	if (sc->event_res != NULL)
127 		panic("%s is called without intr teardown", __func__);
128 	sc->event_rid = 1;
129 
130 	error = pci_alloc_msi(dev, &msicnt);
131 	if (error) {
132 		device_printf(dev, "Couldn't find event MSI IRQ resource.\n");
133 		return (ENOENT);
134 	}
135 
136 	sc->event_res = bus_alloc_resource_any(dev, SYS_RES_IRQ,
137 	    &sc->event_rid, RF_ACTIVE);
138 	if (sc->event_res == NULL) {
139 		device_printf(dev, "Unable to allocate event INTR resource.\n");
140 		error = ENOMEM;
141 		goto fail;
142 	}
143 
144 	error = bus_setup_intr(dev, sc->event_res, INTR_TYPE_MISC | INTR_MPSAFE,
145 	    NULL, handler, arg, &sc->event_tag);
146 	if (error) {
147 		device_printf(dev, "Fail to setup event intr\n");
148 		goto fail;
149 	}
150 
151 	bus_describe_intr(dev, sc->event_res, sc->event_tag, "%s", desc);
152 	return (0);
153 
154 fail:
155 	ivhd_teardown_intr(dev);
156 	return (error);
157 }
158 
159 static int
160 ivhd_teardown_intr(device_t dev)
161 {
162 	struct amdiommu_softc *sc;
163 
164 	sc = device_get_softc(dev);
165 
166 	if (sc->event_tag != NULL) {
167 		bus_teardown_intr(dev, sc->event_res, sc->event_tag);
168 		sc->event_tag = NULL;
169 	}
170 	if (sc->event_res != NULL) {
171 		bus_release_resource(dev, SYS_RES_IRQ, sc->event_rid,
172 		    sc->event_res);
173 		sc->event_res = NULL;
174 	}
175 	pci_release_msi(dev);
176 	return (0);
177 }
178 
179 /* This driver has to be loaded before ivhd */
180 DRIVER_MODULE(amdiommu, pci, amdiommu_driver, 0, 0);
181 MODULE_DEPEND(amdiommu, pci, 1, 1, 1);
182