xref: /openbmc/qemu/hw/misc/iotkit-sysinfo.c (revision 1d52866f)
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  * http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ecm0601256/index.html
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 "trace.h"
23 #include "qapi/error.h"
24 #include "sysemu/sysemu.h"
25 #include "hw/sysbus.h"
26 #include "hw/registerfields.h"
27 #include "hw/misc/iotkit-sysinfo.h"
28 
29 REG32(SYS_VERSION, 0x0)
30 REG32(SYS_CONFIG, 0x4)
31 REG32(PID4, 0xfd0)
32 REG32(PID5, 0xfd4)
33 REG32(PID6, 0xfd8)
34 REG32(PID7, 0xfdc)
35 REG32(PID0, 0xfe0)
36 REG32(PID1, 0xfe4)
37 REG32(PID2, 0xfe8)
38 REG32(PID3, 0xfec)
39 REG32(CID0, 0xff0)
40 REG32(CID1, 0xff4)
41 REG32(CID2, 0xff8)
42 REG32(CID3, 0xffc)
43 
44 /* PID/CID values */
45 static const int sysinfo_id[] = {
46     0x04, 0x00, 0x00, 0x00, /* PID4..PID7 */
47     0x58, 0xb8, 0x0b, 0x00, /* PID0..PID3 */
48     0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
49 };
50 
51 static uint64_t iotkit_sysinfo_read(void *opaque, hwaddr offset,
52                                     unsigned size)
53 {
54     uint64_t r;
55 
56     switch (offset) {
57     case A_SYS_VERSION:
58         r = 0x41743;
59         break;
60 
61     case A_SYS_CONFIG:
62         r = 0x31;
63         break;
64     case A_PID4 ... A_CID3:
65         r = sysinfo_id[(offset - A_PID4) / 4];
66         break;
67     default:
68         qemu_log_mask(LOG_GUEST_ERROR,
69                       "IoTKit SysInfo read: bad offset %x\n", (int)offset);
70         r = 0;
71         break;
72     }
73     trace_iotkit_sysinfo_read(offset, r, size);
74     return r;
75 }
76 
77 static void iotkit_sysinfo_write(void *opaque, hwaddr offset,
78                                  uint64_t value, unsigned size)
79 {
80     trace_iotkit_sysinfo_write(offset, value, size);
81 
82     qemu_log_mask(LOG_GUEST_ERROR,
83                   "IoTKit SysInfo: write to RO offset 0x%x\n", (int)offset);
84 }
85 
86 static const MemoryRegionOps iotkit_sysinfo_ops = {
87     .read = iotkit_sysinfo_read,
88     .write = iotkit_sysinfo_write,
89     .endianness = DEVICE_LITTLE_ENDIAN,
90     /* byte/halfword accesses are just zero-padded on reads and writes */
91     .impl.min_access_size = 4,
92     .impl.max_access_size = 4,
93     .valid.min_access_size = 1,
94     .valid.max_access_size = 4,
95 };
96 
97 static void iotkit_sysinfo_init(Object *obj)
98 {
99     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
100     IoTKitSysInfo *s = IOTKIT_SYSINFO(obj);
101 
102     memory_region_init_io(&s->iomem, obj, &iotkit_sysinfo_ops,
103                           s, "iotkit-sysinfo", 0x1000);
104     sysbus_init_mmio(sbd, &s->iomem);
105 }
106 
107 static void iotkit_sysinfo_class_init(ObjectClass *klass, void *data)
108 {
109     /*
110      * This device has no guest-modifiable state and so it
111      * does not need a reset function or VMState.
112      */
113 }
114 
115 static const TypeInfo iotkit_sysinfo_info = {
116     .name = TYPE_IOTKIT_SYSINFO,
117     .parent = TYPE_SYS_BUS_DEVICE,
118     .instance_size = sizeof(IoTKitSysInfo),
119     .instance_init = iotkit_sysinfo_init,
120     .class_init = iotkit_sysinfo_class_init,
121 };
122 
123 static void iotkit_sysinfo_register_types(void)
124 {
125     type_register_static(&iotkit_sysinfo_info);
126 }
127 
128 type_init(iotkit_sysinfo_register_types);
129