1 /*
2 * Allwinner Security ID emulation
3 *
4 * Copyright (C) 2019 Niek Linnenbank <nieklinnenbank@gmail.com>
5 *
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include "qemu/osdep.h"
21 #include "qemu/units.h"
22 #include "hw/sysbus.h"
23 #include "migration/vmstate.h"
24 #include "qemu/log.h"
25 #include "qemu/module.h"
26 #include "qemu/guest-random.h"
27 #include "qapi/error.h"
28 #include "hw/qdev-properties.h"
29 #include "hw/qdev-properties-system.h"
30 #include "hw/misc/allwinner-sid.h"
31 #include "trace.h"
32
33 /* SID register offsets */
34 enum {
35 REG_PRCTL = 0x40, /* Control */
36 REG_RDKEY = 0x60, /* Read Key */
37 };
38
39 /* SID register flags */
40 enum {
41 REG_PRCTL_WRITE = 0x0002, /* Unknown write flag */
42 REG_PRCTL_OP_LOCK = 0xAC00, /* Lock operation */
43 };
44
allwinner_sid_read(void * opaque,hwaddr offset,unsigned size)45 static uint64_t allwinner_sid_read(void *opaque, hwaddr offset,
46 unsigned size)
47 {
48 const AwSidState *s = AW_SID(opaque);
49 uint64_t val = 0;
50
51 switch (offset) {
52 case REG_PRCTL: /* Control */
53 val = s->control;
54 break;
55 case REG_RDKEY: /* Read Key */
56 val = s->rdkey;
57 break;
58 default:
59 qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
60 __func__, (uint32_t)offset);
61 return 0;
62 }
63
64 trace_allwinner_sid_read(offset, val, size);
65
66 return val;
67 }
68
allwinner_sid_write(void * opaque,hwaddr offset,uint64_t val,unsigned size)69 static void allwinner_sid_write(void *opaque, hwaddr offset,
70 uint64_t val, unsigned size)
71 {
72 AwSidState *s = AW_SID(opaque);
73
74 trace_allwinner_sid_write(offset, val, size);
75
76 switch (offset) {
77 case REG_PRCTL: /* Control */
78 s->control = val;
79
80 if ((s->control & REG_PRCTL_OP_LOCK) &&
81 (s->control & REG_PRCTL_WRITE)) {
82 uint32_t id = s->control >> 16;
83
84 if (id <= sizeof(QemuUUID) - sizeof(s->rdkey)) {
85 s->rdkey = ldl_be_p(&s->identifier.data[id]);
86 }
87 }
88 s->control &= ~REG_PRCTL_WRITE;
89 break;
90 case REG_RDKEY: /* Read Key */
91 break;
92 default:
93 qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
94 __func__, (uint32_t)offset);
95 break;
96 }
97 }
98
99 static const MemoryRegionOps allwinner_sid_ops = {
100 .read = allwinner_sid_read,
101 .write = allwinner_sid_write,
102 .endianness = DEVICE_NATIVE_ENDIAN,
103 .valid = {
104 .min_access_size = 4,
105 .max_access_size = 4,
106 },
107 .impl.min_access_size = 4,
108 };
109
allwinner_sid_reset(DeviceState * dev)110 static void allwinner_sid_reset(DeviceState *dev)
111 {
112 AwSidState *s = AW_SID(dev);
113
114 /* Set default values for registers */
115 s->control = 0;
116 s->rdkey = 0;
117 }
118
allwinner_sid_init(Object * obj)119 static void allwinner_sid_init(Object *obj)
120 {
121 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
122 AwSidState *s = AW_SID(obj);
123
124 /* Memory mapping */
125 memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_sid_ops, s,
126 TYPE_AW_SID, 1 * KiB);
127 sysbus_init_mmio(sbd, &s->iomem);
128 }
129
130 static Property allwinner_sid_properties[] = {
131 DEFINE_PROP_UUID_NODEFAULT("identifier", AwSidState, identifier),
132 DEFINE_PROP_END_OF_LIST()
133 };
134
135 static const VMStateDescription allwinner_sid_vmstate = {
136 .name = "allwinner-sid",
137 .version_id = 1,
138 .minimum_version_id = 1,
139 .fields = (const VMStateField[]) {
140 VMSTATE_UINT32(control, AwSidState),
141 VMSTATE_UINT32(rdkey, AwSidState),
142 VMSTATE_UINT8_ARRAY_V(identifier.data, AwSidState, sizeof(QemuUUID), 1),
143 VMSTATE_END_OF_LIST()
144 }
145 };
146
allwinner_sid_class_init(ObjectClass * klass,void * data)147 static void allwinner_sid_class_init(ObjectClass *klass, void *data)
148 {
149 DeviceClass *dc = DEVICE_CLASS(klass);
150
151 device_class_set_legacy_reset(dc, allwinner_sid_reset);
152 dc->vmsd = &allwinner_sid_vmstate;
153 device_class_set_props(dc, allwinner_sid_properties);
154 }
155
156 static const TypeInfo allwinner_sid_info = {
157 .name = TYPE_AW_SID,
158 .parent = TYPE_SYS_BUS_DEVICE,
159 .instance_init = allwinner_sid_init,
160 .instance_size = sizeof(AwSidState),
161 .class_init = allwinner_sid_class_init,
162 };
163
allwinner_sid_register(void)164 static void allwinner_sid_register(void)
165 {
166 type_register_static(&allwinner_sid_info);
167 }
168
169 type_init(allwinner_sid_register)
170