xref: /openbmc/qemu/hw/intc/arm_gicv3_its_kvm.c (revision 30b6852c)
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     void (*parent_reset)(DeviceState *dev);
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_its_init_mmio(s, NULL, NULL);
110 
111     if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
112         GITS_CTLR)) {
113         error_setg(&s->migration_blocker, "This operating system kernel "
114                    "does not support vITS migration");
115         if (migrate_add_blocker(s->migration_blocker, errp) < 0) {
116             error_free(s->migration_blocker);
117             return;
118         }
119     } else {
120         qemu_add_vm_change_state_handler(vm_change_state_handler, s);
121     }
122 
123     kvm_msi_use_devid = true;
124     kvm_gsi_direct_mapping = false;
125     kvm_msi_via_irqfd_allowed = kvm_irqfds_enabled();
126 }
127 
128 /**
129  * kvm_arm_its_pre_save - handles the saving of ITS registers.
130  * ITS tables are flushed into guest RAM separately and earlier,
131  * through the VM change state handler, since at the moment pre_save()
132  * is called, the guest RAM has already been saved.
133  */
134 static void kvm_arm_its_pre_save(GICv3ITSState *s)
135 {
136     int i;
137 
138     for (i = 0; i < 8; i++) {
139         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
140                           GITS_BASER + i * 8, &s->baser[i], false,
141                           &error_abort);
142     }
143 
144     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
145                       GITS_CTLR, &s->ctlr, false, &error_abort);
146 
147     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
148                       GITS_CBASER, &s->cbaser, false, &error_abort);
149 
150     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
151                       GITS_CREADR, &s->creadr, false, &error_abort);
152 
153     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
154                       GITS_CWRITER, &s->cwriter, false, &error_abort);
155 
156     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
157                       GITS_IIDR, &s->iidr, false, &error_abort);
158 }
159 
160 /**
161  * kvm_arm_its_post_load - Restore both the ITS registers and tables
162  */
163 static void kvm_arm_its_post_load(GICv3ITSState *s)
164 {
165     int i;
166 
167     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
168                       GITS_IIDR, &s->iidr, true, &error_abort);
169 
170     /*
171      * must be written before GITS_CREADR since GITS_CBASER write
172      * access resets GITS_CREADR.
173      */
174     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
175                       GITS_CBASER, &s->cbaser, true, &error_abort);
176 
177     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
178                       GITS_CREADR, &s->creadr, true, &error_abort);
179 
180     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
181                       GITS_CWRITER, &s->cwriter, true, &error_abort);
182 
183 
184     for (i = 0; i < 8; i++) {
185         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
186                           GITS_BASER + i * 8, &s->baser[i], true,
187                           &error_abort);
188     }
189 
190     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
191                       KVM_DEV_ARM_ITS_RESTORE_TABLES, NULL, true,
192                       &error_abort);
193 
194     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
195                       GITS_CTLR, &s->ctlr, true, &error_abort);
196 }
197 
198 static void kvm_arm_its_reset(DeviceState *dev)
199 {
200     GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
201     KVMARMITSClass *c = KVM_ARM_ITS_GET_CLASS(s);
202     int i;
203 
204     c->parent_reset(dev);
205 
206     if (kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
207                                KVM_DEV_ARM_ITS_CTRL_RESET)) {
208         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
209                           KVM_DEV_ARM_ITS_CTRL_RESET, NULL, true, &error_abort);
210         return;
211     }
212 
213     warn_report("ITS KVM: full reset is not supported by the host kernel");
214 
215     if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
216                                GITS_CTLR)) {
217         return;
218     }
219 
220     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
221                       GITS_CTLR, &s->ctlr, true, &error_abort);
222 
223     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
224                       GITS_CBASER, &s->cbaser, true, &error_abort);
225 
226     for (i = 0; i < 8; i++) {
227         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
228                           GITS_BASER + i * 8, &s->baser[i], true,
229                           &error_abort);
230     }
231 }
232 
233 static Property kvm_arm_its_props[] = {
234     DEFINE_PROP_LINK("parent-gicv3", GICv3ITSState, gicv3, "kvm-arm-gicv3",
235                      GICv3State *),
236     DEFINE_PROP_END_OF_LIST(),
237 };
238 
239 static void kvm_arm_its_class_init(ObjectClass *klass, void *data)
240 {
241     DeviceClass *dc = DEVICE_CLASS(klass);
242     GICv3ITSCommonClass *icc = ARM_GICV3_ITS_COMMON_CLASS(klass);
243     KVMARMITSClass *ic = KVM_ARM_ITS_CLASS(klass);
244 
245     dc->realize = kvm_arm_its_realize;
246     device_class_set_props(dc, kvm_arm_its_props);
247     device_class_set_parent_reset(dc, kvm_arm_its_reset, &ic->parent_reset);
248     icc->send_msi = kvm_its_send_msi;
249     icc->pre_save = kvm_arm_its_pre_save;
250     icc->post_load = kvm_arm_its_post_load;
251 }
252 
253 static const TypeInfo kvm_arm_its_info = {
254     .name = TYPE_KVM_ARM_ITS,
255     .parent = TYPE_ARM_GICV3_ITS_COMMON,
256     .instance_size = sizeof(GICv3ITSState),
257     .class_init = kvm_arm_its_class_init,
258     .class_size = sizeof(KVMARMITSClass),
259 };
260 
261 static void kvm_arm_its_register_types(void)
262 {
263     type_register_static(&kvm_arm_its_info);
264 }
265 
266 type_init(kvm_arm_its_register_types)
267