xref: /openbmc/qemu/hw/intc/arm_gicv3_its_kvm.c (revision 8d8cb956)
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 "hw/intc/arm_gicv3_its_common.h"
24 #include "sysemu/sysemu.h"
25 #include "sysemu/kvm.h"
26 #include "kvm_arm.h"
27 #include "migration/blocker.h"
28 
29 #define TYPE_KVM_ARM_ITS "arm-its-kvm"
30 #define KVM_ARM_ITS(obj) OBJECT_CHECK(GICv3ITSState, (obj), TYPE_KVM_ARM_ITS)
31 
32 static int kvm_its_send_msi(GICv3ITSState *s, uint32_t value, uint16_t devid)
33 {
34     struct kvm_msi msi;
35 
36     if (unlikely(!s->translater_gpa_known)) {
37         MemoryRegion *mr = &s->iomem_its_translation;
38         MemoryRegionSection mrs;
39 
40         mrs = memory_region_find(mr, 0, 1);
41         memory_region_unref(mrs.mr);
42         s->gits_translater_gpa = mrs.offset_within_address_space + 0x40;
43         s->translater_gpa_known = true;
44     }
45 
46     msi.address_lo = extract64(s->gits_translater_gpa, 0, 32);
47     msi.address_hi = extract64(s->gits_translater_gpa, 32, 32);
48     msi.data = le32_to_cpu(value);
49     msi.flags = KVM_MSI_VALID_DEVID;
50     msi.devid = devid;
51     memset(msi.pad, 0, sizeof(msi.pad));
52 
53     return kvm_vm_ioctl(kvm_state, KVM_SIGNAL_MSI, &msi);
54 }
55 
56 /**
57  * vm_change_state_handler - VM change state callback aiming at flushing
58  * ITS tables into guest RAM
59  *
60  * The tables get flushed to guest RAM whenever the VM gets stopped.
61  */
62 static void vm_change_state_handler(void *opaque, int running,
63                                     RunState state)
64 {
65     GICv3ITSState *s = (GICv3ITSState *)opaque;
66     Error *err = NULL;
67 
68     if (running) {
69         return;
70     }
71 
72     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
73                       KVM_DEV_ARM_ITS_SAVE_TABLES, NULL, true, &err);
74     if (err) {
75         error_report_err(err);
76     }
77 }
78 
79 static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
80 {
81     GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
82     Error *local_err = NULL;
83 
84     s->dev_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_ITS, false);
85     if (s->dev_fd < 0) {
86         error_setg_errno(errp, -s->dev_fd, "error creating in-kernel ITS");
87         return;
88     }
89 
90     /* explicit init of the ITS */
91     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
92                       KVM_DEV_ARM_VGIC_CTRL_INIT, NULL, true, &error_abort);
93 
94     /* register the base address */
95     kvm_arm_register_device(&s->iomem_its_cntrl, -1, KVM_DEV_ARM_VGIC_GRP_ADDR,
96                             KVM_VGIC_ITS_ADDR_TYPE, s->dev_fd);
97 
98     gicv3_its_init_mmio(s, NULL);
99 
100     if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
101         GITS_CTLR)) {
102         error_setg(&s->migration_blocker, "This operating system kernel "
103                    "does not support vITS migration");
104         migrate_add_blocker(s->migration_blocker, &local_err);
105         if (local_err) {
106             error_propagate(errp, local_err);
107             error_free(s->migration_blocker);
108             return;
109         }
110     } else {
111         qemu_add_vm_change_state_handler(vm_change_state_handler, s);
112     }
113 
114     kvm_msi_use_devid = true;
115     kvm_gsi_direct_mapping = false;
116     kvm_msi_via_irqfd_allowed = kvm_irqfds_enabled();
117 }
118 
119 /**
120  * kvm_arm_its_pre_save - handles the saving of ITS registers.
121  * ITS tables are flushed into guest RAM separately and earlier,
122  * through the VM change state handler, since at the moment pre_save()
123  * is called, the guest RAM has already been saved.
124  */
125 static void kvm_arm_its_pre_save(GICv3ITSState *s)
126 {
127     int i;
128 
129     for (i = 0; i < 8; i++) {
130         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
131                           GITS_BASER + i * 8, &s->baser[i], false,
132                           &error_abort);
133     }
134 
135     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
136                       GITS_CTLR, &s->ctlr, false, &error_abort);
137 
138     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
139                       GITS_CBASER, &s->cbaser, false, &error_abort);
140 
141     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
142                       GITS_CREADR, &s->creadr, false, &error_abort);
143 
144     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
145                       GITS_CWRITER, &s->cwriter, false, &error_abort);
146 
147     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
148                       GITS_IIDR, &s->iidr, false, &error_abort);
149 }
150 
151 /**
152  * kvm_arm_its_post_load - Restore both the ITS registers and tables
153  */
154 static void kvm_arm_its_post_load(GICv3ITSState *s)
155 {
156     int i;
157 
158     if (!s->iidr) {
159         return;
160     }
161 
162     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
163                       GITS_IIDR, &s->iidr, true, &error_abort);
164 
165     /*
166      * must be written before GITS_CREADR since GITS_CBASER write
167      * access resets GITS_CREADR.
168      */
169     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
170                       GITS_CBASER, &s->cbaser, true, &error_abort);
171 
172     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
173                       GITS_CREADR, &s->creadr, true, &error_abort);
174 
175     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
176                       GITS_CWRITER, &s->cwriter, true, &error_abort);
177 
178 
179     for (i = 0; i < 8; i++) {
180         kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
181                           GITS_BASER + i * 8, &s->baser[i], true,
182                           &error_abort);
183     }
184 
185     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
186                       KVM_DEV_ARM_ITS_RESTORE_TABLES, NULL, true,
187                       &error_abort);
188 
189     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
190                       GITS_CTLR, &s->ctlr, true, &error_abort);
191 }
192 
193 static Property kvm_arm_its_props[] = {
194     DEFINE_PROP_LINK("parent-gicv3", GICv3ITSState, gicv3, "kvm-arm-gicv3",
195                      GICv3State *),
196     DEFINE_PROP_END_OF_LIST(),
197 };
198 
199 static void kvm_arm_its_class_init(ObjectClass *klass, void *data)
200 {
201     DeviceClass *dc = DEVICE_CLASS(klass);
202     GICv3ITSCommonClass *icc = ARM_GICV3_ITS_COMMON_CLASS(klass);
203 
204     dc->realize = kvm_arm_its_realize;
205     dc->props   = kvm_arm_its_props;
206     icc->send_msi = kvm_its_send_msi;
207     icc->pre_save = kvm_arm_its_pre_save;
208     icc->post_load = kvm_arm_its_post_load;
209 }
210 
211 static const TypeInfo kvm_arm_its_info = {
212     .name = TYPE_KVM_ARM_ITS,
213     .parent = TYPE_ARM_GICV3_ITS_COMMON,
214     .instance_size = sizeof(GICv3ITSState),
215     .class_init = kvm_arm_its_class_init,
216 };
217 
218 static void kvm_arm_its_register_types(void)
219 {
220     type_register_static(&kvm_arm_its_info);
221 }
222 
223 type_init(kvm_arm_its_register_types)
224