xref: /openbmc/qemu/hw/misc/iotkit-sysinfo.c (revision cba42d61)
1 /*
2  * ARM IoTKit system information block
3  *
4  * Copyright (c) 2018 Linaro Limited
5  * Written by Peter Maydell
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License version 2 or
9  *  (at your option) any later version.
10  */
11 
12 /*
13  * This is a model of the "system information block" which is part of the
14  * Arm IoTKit and documented in
15  * https://developer.arm.com/documentation/ecm0601256/latest
16  * It consists of 2 read-only version/config registers, plus the
17  * usual ID registers.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu/log.h"
22 #include "qemu/module.h"
23 #include "trace.h"
24 #include "qapi/error.h"
25 #include "hw/sysbus.h"
26 #include "hw/registerfields.h"
27 #include "hw/misc/iotkit-sysinfo.h"
28 #include "hw/qdev-properties.h"
29 
30 REG32(SYS_VERSION, 0x0)
31 REG32(SYS_CONFIG, 0x4)
32 REG32(PID4, 0xfd0)
33 REG32(PID5, 0xfd4)
34 REG32(PID6, 0xfd8)
35 REG32(PID7, 0xfdc)
36 REG32(PID0, 0xfe0)
37 REG32(PID1, 0xfe4)
38 REG32(PID2, 0xfe8)
39 REG32(PID3, 0xfec)
40 REG32(CID0, 0xff0)
41 REG32(CID1, 0xff4)
42 REG32(CID2, 0xff8)
43 REG32(CID3, 0xffc)
44 
45 /* PID/CID values */
46 static const int sysinfo_id[] = {
47     0x04, 0x00, 0x00, 0x00, /* PID4..PID7 */
48     0x58, 0xb8, 0x0b, 0x00, /* PID0..PID3 */
49     0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
50 };
51 
52 static uint64_t iotkit_sysinfo_read(void *opaque, hwaddr offset,
53                                     unsigned size)
54 {
55     IoTKitSysInfo *s = IOTKIT_SYSINFO(opaque);
56     uint64_t r;
57 
58     switch (offset) {
59     case A_SYS_VERSION:
60         r = s->sys_version;
61         break;
62 
63     case A_SYS_CONFIG:
64         r = s->sys_config;
65         break;
66     case A_PID4 ... A_CID3:
67         r = sysinfo_id[(offset - A_PID4) / 4];
68         break;
69     default:
70         qemu_log_mask(LOG_GUEST_ERROR,
71                       "IoTKit SysInfo read: bad offset %x\n", (int)offset);
72         r = 0;
73         break;
74     }
75     trace_iotkit_sysinfo_read(offset, r, size);
76     return r;
77 }
78 
79 static void iotkit_sysinfo_write(void *opaque, hwaddr offset,
80                                  uint64_t value, unsigned size)
81 {
82     trace_iotkit_sysinfo_write(offset, value, size);
83 
84     qemu_log_mask(LOG_GUEST_ERROR,
85                   "IoTKit SysInfo: write to RO offset 0x%x\n", (int)offset);
86 }
87 
88 static const MemoryRegionOps iotkit_sysinfo_ops = {
89     .read = iotkit_sysinfo_read,
90     .write = iotkit_sysinfo_write,
91     .endianness = DEVICE_LITTLE_ENDIAN,
92     /* byte/halfword accesses are just zero-padded on reads and writes */
93     .impl.min_access_size = 4,
94     .impl.max_access_size = 4,
95     .valid.min_access_size = 1,
96     .valid.max_access_size = 4,
97 };
98 
99 static Property iotkit_sysinfo_props[] = {
100     DEFINE_PROP_UINT32("SYS_VERSION", IoTKitSysInfo, sys_version, 0),
101     DEFINE_PROP_UINT32("SYS_CONFIG", IoTKitSysInfo, sys_config, 0),
102     DEFINE_PROP_END_OF_LIST()
103 };
104 
105 static void iotkit_sysinfo_init(Object *obj)
106 {
107     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
108     IoTKitSysInfo *s = IOTKIT_SYSINFO(obj);
109 
110     memory_region_init_io(&s->iomem, obj, &iotkit_sysinfo_ops,
111                           s, "iotkit-sysinfo", 0x1000);
112     sysbus_init_mmio(sbd, &s->iomem);
113 }
114 
115 static void iotkit_sysinfo_class_init(ObjectClass *klass, void *data)
116 {
117     DeviceClass *dc = DEVICE_CLASS(klass);
118 
119     /*
120      * This device has no guest-modifiable state and so it
121      * does not need a reset function or VMState.
122      */
123 
124     device_class_set_props(dc, iotkit_sysinfo_props);
125 }
126 
127 static const TypeInfo iotkit_sysinfo_info = {
128     .name = TYPE_IOTKIT_SYSINFO,
129     .parent = TYPE_SYS_BUS_DEVICE,
130     .instance_size = sizeof(IoTKitSysInfo),
131     .instance_init = iotkit_sysinfo_init,
132     .class_init = iotkit_sysinfo_class_init,
133 };
134 
135 static void iotkit_sysinfo_register_types(void)
136 {
137     type_register_static(&iotkit_sysinfo_info);
138 }
139 
140 type_init(iotkit_sysinfo_register_types);
141