xref: /openbmc/qemu/hw/intc/arm_gicv3_its_kvm.c (revision 37677d7d)
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 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 "sysemu/sysemu.h"
26 #include "sysemu/kvm.h"
27 #include "kvm_arm.h"
28 #include "migration/blocker.h"
29 
30 #define TYPE_KVM_ARM_ITS "arm-its-kvm"
31 #define KVM_ARM_ITS(obj) OBJECT_CHECK(GICv3ITSState, (obj), TYPE_KVM_ARM_ITS)
32 #define KVM_ARM_ITS_CLASS(klass) \
33      OBJECT_CLASS_CHECK(KVMARMITSClass, (klass), TYPE_KVM_ARM_ITS)
34 #define KVM_ARM_ITS_GET_CLASS(obj) \
35      OBJECT_GET_CLASS(KVMARMITSClass, (obj), TYPE_KVM_ARM_ITS)
36 
37 typedef struct KVMARMITSClass {
38     GICv3ITSCommonClass parent_class;
39     void (*parent_reset)(DeviceState *dev);
40 } KVMARMITSClass;
41 
42 
43 static int kvm_its_send_msi(GICv3ITSState *s, uint32_t value, uint16_t devid)
44 {
45     struct kvm_msi msi;
46 
47     if (unlikely(!s->translater_gpa_known)) {
48         MemoryRegion *mr = &s->iomem_its_translation;
49         MemoryRegionSection mrs;
50 
51         mrs = memory_region_find(mr, 0, 1);
52         memory_region_unref(mrs.mr);
53         s->gits_translater_gpa = mrs.offset_within_address_space + 0x40;
54         s->translater_gpa_known = true;
55     }
56 
57     msi.address_lo = extract64(s->gits_translater_gpa, 0, 32);
58     msi.address_hi = extract64(s->gits_translater_gpa, 32, 32);
59     msi.data = le32_to_cpu(value);
60     msi.flags = KVM_MSI_VALID_DEVID;
61     msi.devid = devid;
62     memset(msi.pad, 0, sizeof(msi.pad));
63 
64     return kvm_vm_ioctl(kvm_state, KVM_SIGNAL_MSI, &msi);
65 }
66 
67 /**
68  * vm_change_state_handler - VM change state callback aiming at flushing
69  * ITS tables into guest RAM
70  *
71  * The tables get flushed to guest RAM whenever the VM gets stopped.
72  */
73 static void vm_change_state_handler(void *opaque, int running,
74                                     RunState state)
75 {
76     GICv3ITSState *s = (GICv3ITSState *)opaque;
77     Error *err = NULL;
78 
79     if (running) {
80         return;
81     }
82 
83     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
84                       KVM_DEV_ARM_ITS_SAVE_TABLES, NULL, true, &err);
85     if (err) {
86         error_report_err(err);
87     }
88 }
89 
90 static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
91 {
92     GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
93     Error *local_err = NULL;
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);
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         migrate_add_blocker(s->migration_blocker, &local_err);
116         if (local_err) {
117             error_propagate(errp, local_err);
118             error_free(s->migration_blocker);
119             return;
120         }
121     } else {
122         qemu_add_vm_change_state_handler(vm_change_state_handler, s);
123     }
124 
125     kvm_msi_use_devid = true;
126     kvm_gsi_direct_mapping = false;
127     kvm_msi_via_irqfd_allowed = kvm_irqfds_enabled();
128 }
129 
130 /**
131  * kvm_arm_its_pre_save - handles the saving of ITS registers.
132  * ITS tables are flushed into guest RAM separately and earlier,
133  * through the VM change state handler, since at the moment pre_save()
134  * is called, the guest RAM has already been saved.
135  */
136 static void kvm_arm_its_pre_save(GICv3ITSState *s)
137 {
138     int i;
139 
140     for (i = 0; i < 8; i++) {
141         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
142                           GITS_BASER + i * 8, &s->baser[i], false,
143                           &error_abort);
144     }
145 
146     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
147                       GITS_CTLR, &s->ctlr, false, &error_abort);
148 
149     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
150                       GITS_CBASER, &s->cbaser, false, &error_abort);
151 
152     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
153                       GITS_CREADR, &s->creadr, false, &error_abort);
154 
155     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
156                       GITS_CWRITER, &s->cwriter, false, &error_abort);
157 
158     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
159                       GITS_IIDR, &s->iidr, false, &error_abort);
160 }
161 
162 /**
163  * kvm_arm_its_post_load - Restore both the ITS registers and tables
164  */
165 static void kvm_arm_its_post_load(GICv3ITSState *s)
166 {
167     int i;
168 
169     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
170                       GITS_IIDR, &s->iidr, true, &error_abort);
171 
172     /*
173      * must be written before GITS_CREADR since GITS_CBASER write
174      * access resets GITS_CREADR.
175      */
176     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
177                       GITS_CBASER, &s->cbaser, true, &error_abort);
178 
179     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
180                       GITS_CREADR, &s->creadr, true, &error_abort);
181 
182     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
183                       GITS_CWRITER, &s->cwriter, true, &error_abort);
184 
185 
186     for (i = 0; i < 8; i++) {
187         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
188                           GITS_BASER + i * 8, &s->baser[i], true,
189                           &error_abort);
190     }
191 
192     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
193                       KVM_DEV_ARM_ITS_RESTORE_TABLES, NULL, true,
194                       &error_abort);
195 
196     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
197                       GITS_CTLR, &s->ctlr, true, &error_abort);
198 }
199 
200 static void kvm_arm_its_reset(DeviceState *dev)
201 {
202     GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
203     KVMARMITSClass *c = KVM_ARM_ITS_GET_CLASS(s);
204     int i;
205 
206     c->parent_reset(dev);
207 
208     if (kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
209                                KVM_DEV_ARM_ITS_CTRL_RESET)) {
210         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
211                           KVM_DEV_ARM_ITS_CTRL_RESET, NULL, true, &error_abort);
212         return;
213     }
214 
215     warn_report("ITS KVM: full reset is not supported by the host kernel");
216 
217     if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
218                                GITS_CTLR)) {
219         return;
220     }
221 
222     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
223                       GITS_CTLR, &s->ctlr, true, &error_abort);
224 
225     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
226                       GITS_CBASER, &s->cbaser, true, &error_abort);
227 
228     for (i = 0; i < 8; i++) {
229         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
230                           GITS_BASER + i * 8, &s->baser[i], true,
231                           &error_abort);
232     }
233 }
234 
235 static Property kvm_arm_its_props[] = {
236     DEFINE_PROP_LINK("parent-gicv3", GICv3ITSState, gicv3, "kvm-arm-gicv3",
237                      GICv3State *),
238     DEFINE_PROP_END_OF_LIST(),
239 };
240 
241 static void kvm_arm_its_class_init(ObjectClass *klass, void *data)
242 {
243     DeviceClass *dc = DEVICE_CLASS(klass);
244     GICv3ITSCommonClass *icc = ARM_GICV3_ITS_COMMON_CLASS(klass);
245     KVMARMITSClass *ic = KVM_ARM_ITS_CLASS(klass);
246 
247     dc->realize = kvm_arm_its_realize;
248     dc->props   = kvm_arm_its_props;
249     device_class_set_parent_reset(dc, kvm_arm_its_reset, &ic->parent_reset);
250     icc->send_msi = kvm_its_send_msi;
251     icc->pre_save = kvm_arm_its_pre_save;
252     icc->post_load = kvm_arm_its_post_load;
253 }
254 
255 static const TypeInfo kvm_arm_its_info = {
256     .name = TYPE_KVM_ARM_ITS,
257     .parent = TYPE_ARM_GICV3_ITS_COMMON,
258     .instance_size = sizeof(GICv3ITSState),
259     .class_init = kvm_arm_its_class_init,
260     .class_size = sizeof(KVMARMITSClass),
261 };
262 
263 static void kvm_arm_its_register_types(void)
264 {
265     type_register_static(&kvm_arm_its_info);
266 }
267 
268 type_init(kvm_arm_its_register_types)
269