xref: /openbmc/qemu/hw/intc/arm_gicv3_its_kvm.c (revision 259ebed4)
1 /*
2  * KVM-based ITS implementation for a GICv3-based system
3  *
4  * Copyright (c) 2015 Samsung Electronics Co., Ltd.
5  * Written by Pavel Fedin <p.fedin@samsung.com>
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qapi/error.h"
23 #include "qemu/module.h"
24 #include "hw/intc/arm_gicv3_its_common.h"
25 #include "hw/qdev-properties.h"
26 #include "sysemu/runstate.h"
27 #include "sysemu/kvm.h"
28 #include "kvm_arm.h"
29 #include "migration/blocker.h"
30 #include "qom/object.h"
31 
32 #define TYPE_KVM_ARM_ITS "arm-its-kvm"
33 typedef struct KVMARMITSClass KVMARMITSClass;
34 /* This is reusing the GICv3ITSState typedef from ARM_GICV3_ITS_COMMON */
35 DECLARE_OBJ_CHECKERS(GICv3ITSState, KVMARMITSClass,
36                      KVM_ARM_ITS, TYPE_KVM_ARM_ITS)
37 
38 struct KVMARMITSClass {
39     GICv3ITSCommonClass parent_class;
40     ResettablePhases parent_phases;
41 };
42 
43 
44 static int kvm_its_send_msi(GICv3ITSState *s, uint32_t value, uint16_t devid)
45 {
46     struct kvm_msi msi;
47 
48     if (unlikely(!s->translater_gpa_known)) {
49         MemoryRegion *mr = &s->iomem_its_translation;
50         MemoryRegionSection mrs;
51 
52         mrs = memory_region_find(mr, 0, 1);
53         memory_region_unref(mrs.mr);
54         s->gits_translater_gpa = mrs.offset_within_address_space + 0x40;
55         s->translater_gpa_known = true;
56     }
57 
58     msi.address_lo = extract64(s->gits_translater_gpa, 0, 32);
59     msi.address_hi = extract64(s->gits_translater_gpa, 32, 32);
60     msi.data = le32_to_cpu(value);
61     msi.flags = KVM_MSI_VALID_DEVID;
62     msi.devid = devid;
63     memset(msi.pad, 0, sizeof(msi.pad));
64 
65     return kvm_vm_ioctl(kvm_state, KVM_SIGNAL_MSI, &msi);
66 }
67 
68 /**
69  * vm_change_state_handler - VM change state callback aiming at flushing
70  * ITS tables into guest RAM
71  *
72  * The tables get flushed to guest RAM whenever the VM gets stopped.
73  */
74 static void vm_change_state_handler(void *opaque, bool running,
75                                     RunState state)
76 {
77     GICv3ITSState *s = (GICv3ITSState *)opaque;
78     Error *err = NULL;
79 
80     if (running) {
81         return;
82     }
83 
84     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
85                       KVM_DEV_ARM_ITS_SAVE_TABLES, NULL, true, &err);
86     if (err) {
87         error_report_err(err);
88     }
89 }
90 
91 static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
92 {
93     GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
94 
95     s->dev_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_ITS, false);
96     if (s->dev_fd < 0) {
97         error_setg_errno(errp, -s->dev_fd, "error creating in-kernel ITS");
98         return;
99     }
100 
101     /* explicit init of the ITS */
102     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
103                       KVM_DEV_ARM_VGIC_CTRL_INIT, NULL, true, &error_abort);
104 
105     /* register the base address */
106     kvm_arm_register_device(&s->iomem_its_cntrl, -1, KVM_DEV_ARM_VGIC_GRP_ADDR,
107                             KVM_VGIC_ITS_ADDR_TYPE, s->dev_fd, 0);
108 
109     gicv3_add_its(s->gicv3, dev);
110 
111     gicv3_its_init_mmio(s, NULL, NULL);
112 
113     if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
114         GITS_CTLR)) {
115         error_setg(&s->migration_blocker, "This operating system kernel "
116                    "does not support vITS migration");
117         if (migrate_add_blocker(&s->migration_blocker, errp) < 0) {
118             return;
119         }
120     } else {
121         qemu_add_vm_change_state_handler(vm_change_state_handler, s);
122     }
123 
124     kvm_msi_use_devid = true;
125     kvm_gsi_direct_mapping = false;
126     kvm_msi_via_irqfd_allowed = true;
127 }
128 
129 /**
130  * kvm_arm_its_pre_save - handles the saving of ITS registers.
131  * ITS tables are flushed into guest RAM separately and earlier,
132  * through the VM change state handler, since at the moment pre_save()
133  * is called, the guest RAM has already been saved.
134  */
135 static void kvm_arm_its_pre_save(GICv3ITSState *s)
136 {
137     int i;
138 
139     for (i = 0; i < 8; i++) {
140         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
141                           GITS_BASER + i * 8, &s->baser[i], false,
142                           &error_abort);
143     }
144 
145     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
146                       GITS_CTLR, &s->ctlr, false, &error_abort);
147 
148     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
149                       GITS_CBASER, &s->cbaser, false, &error_abort);
150 
151     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
152                       GITS_CREADR, &s->creadr, false, &error_abort);
153 
154     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
155                       GITS_CWRITER, &s->cwriter, false, &error_abort);
156 
157     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
158                       GITS_IIDR, &s->iidr, false, &error_abort);
159 }
160 
161 /**
162  * kvm_arm_its_post_load - Restore both the ITS registers and tables
163  */
164 static void kvm_arm_its_post_load(GICv3ITSState *s)
165 {
166     int i;
167 
168     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
169                       GITS_IIDR, &s->iidr, true, &error_abort);
170 
171     /*
172      * must be written before GITS_CREADR since GITS_CBASER write
173      * access resets GITS_CREADR.
174      */
175     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
176                       GITS_CBASER, &s->cbaser, true, &error_abort);
177 
178     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
179                       GITS_CREADR, &s->creadr, true, &error_abort);
180 
181     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
182                       GITS_CWRITER, &s->cwriter, true, &error_abort);
183 
184 
185     for (i = 0; i < 8; i++) {
186         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
187                           GITS_BASER + i * 8, &s->baser[i], true,
188                           &error_abort);
189     }
190 
191     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
192                       KVM_DEV_ARM_ITS_RESTORE_TABLES, NULL, true,
193                       &error_abort);
194 
195     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
196                       GITS_CTLR, &s->ctlr, true, &error_abort);
197 }
198 
199 static void kvm_arm_its_reset_hold(Object *obj)
200 {
201     GICv3ITSState *s = ARM_GICV3_ITS_COMMON(obj);
202     KVMARMITSClass *c = KVM_ARM_ITS_GET_CLASS(s);
203     int i;
204 
205     if (c->parent_phases.hold) {
206         c->parent_phases.hold(obj);
207     }
208 
209     if (kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
210                                KVM_DEV_ARM_ITS_CTRL_RESET)) {
211         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
212                           KVM_DEV_ARM_ITS_CTRL_RESET, NULL, true, &error_abort);
213         return;
214     }
215 
216     warn_report("ITS KVM: full reset is not supported by the host kernel");
217 
218     if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
219                                GITS_CTLR)) {
220         return;
221     }
222 
223     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
224                       GITS_CTLR, &s->ctlr, true, &error_abort);
225 
226     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
227                       GITS_CBASER, &s->cbaser, true, &error_abort);
228 
229     for (i = 0; i < 8; i++) {
230         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
231                           GITS_BASER + i * 8, &s->baser[i], true,
232                           &error_abort);
233     }
234 }
235 
236 static Property kvm_arm_its_props[] = {
237     DEFINE_PROP_LINK("parent-gicv3", GICv3ITSState, gicv3, "kvm-arm-gicv3",
238                      GICv3State *),
239     DEFINE_PROP_END_OF_LIST(),
240 };
241 
242 static void kvm_arm_its_class_init(ObjectClass *klass, void *data)
243 {
244     DeviceClass *dc = DEVICE_CLASS(klass);
245     ResettableClass *rc = RESETTABLE_CLASS(klass);
246     GICv3ITSCommonClass *icc = ARM_GICV3_ITS_COMMON_CLASS(klass);
247     KVMARMITSClass *ic = KVM_ARM_ITS_CLASS(klass);
248 
249     dc->realize = kvm_arm_its_realize;
250     device_class_set_props(dc, kvm_arm_its_props);
251     resettable_class_set_parent_phases(rc, NULL, kvm_arm_its_reset_hold, NULL,
252                                        &ic->parent_phases);
253     icc->send_msi = kvm_its_send_msi;
254     icc->pre_save = kvm_arm_its_pre_save;
255     icc->post_load = kvm_arm_its_post_load;
256 }
257 
258 static const TypeInfo kvm_arm_its_info = {
259     .name = TYPE_KVM_ARM_ITS,
260     .parent = TYPE_ARM_GICV3_ITS_COMMON,
261     .instance_size = sizeof(GICv3ITSState),
262     .class_init = kvm_arm_its_class_init,
263     .class_size = sizeof(KVMARMITSClass),
264 };
265 
266 static void kvm_arm_its_register_types(void)
267 {
268     type_register_static(&kvm_arm_its_info);
269 }
270 
271 type_init(kvm_arm_its_register_types)
272