xref: /openbmc/qemu/hw/misc/armsse-cpuid.c (revision a68694cd)
1 /*
2  * ARM SSE-200 CPU_IDENTITY register block
3  *
4  * Copyright (c) 2019 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 "CPU_IDENTITY" register block which is part of the
14  * Arm SSE-200 and documented in
15  * http://infocenter.arm.com/help/topic/com.arm.doc.101104_0100_00_en/corelink_sse200_subsystem_for_embedded_technical_reference_manual_101104_0100_00_en.pdf
16  *
17  * It consists of one read-only CPUID register (set by QOM property), plus the
18  * usual ID registers.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qemu/log.h"
23 #include "qemu/module.h"
24 #include "trace.h"
25 #include "qapi/error.h"
26 #include "hw/sysbus.h"
27 #include "hw/registerfields.h"
28 #include "hw/misc/armsse-cpuid.h"
29 #include "hw/qdev-properties.h"
30 
31 REG32(CPUID, 0x0)
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 armsse_cpuid_read(void *opaque, hwaddr offset,
53                                     unsigned size)
54 {
55     ARMSSECPUID *s = ARMSSE_CPUID(opaque);
56     uint64_t r;
57 
58     switch (offset) {
59     case A_CPUID:
60         r = s->cpuid;
61         break;
62     case A_PID4 ... A_CID3:
63         r = sysinfo_id[(offset - A_PID4) / 4];
64         break;
65     default:
66         qemu_log_mask(LOG_GUEST_ERROR,
67                       "SSE CPU_IDENTITY read: bad offset 0x%x\n", (int)offset);
68         r = 0;
69         break;
70     }
71     trace_armsse_cpuid_read(offset, r, size);
72     return r;
73 }
74 
75 static void armsse_cpuid_write(void *opaque, hwaddr offset,
76                                  uint64_t value, unsigned size)
77 {
78     trace_armsse_cpuid_write(offset, value, size);
79 
80     qemu_log_mask(LOG_GUEST_ERROR,
81                   "SSE CPU_IDENTITY: write to RO offset 0x%x\n", (int)offset);
82 }
83 
84 static const MemoryRegionOps armsse_cpuid_ops = {
85     .read = armsse_cpuid_read,
86     .write = armsse_cpuid_write,
87     .endianness = DEVICE_LITTLE_ENDIAN,
88     /* byte/halfword accesses are just zero-padded on reads and writes */
89     .impl.min_access_size = 4,
90     .impl.max_access_size = 4,
91     .valid.min_access_size = 1,
92     .valid.max_access_size = 4,
93 };
94 
95 static Property armsse_cpuid_props[] = {
96     DEFINE_PROP_UINT32("CPUID", ARMSSECPUID, cpuid, 0),
97     DEFINE_PROP_END_OF_LIST()
98 };
99 
100 static void armsse_cpuid_init(Object *obj)
101 {
102     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
103     ARMSSECPUID *s = ARMSSE_CPUID(obj);
104 
105     memory_region_init_io(&s->iomem, obj, &armsse_cpuid_ops,
106                           s, "armsse-cpuid", 0x1000);
107     sysbus_init_mmio(sbd, &s->iomem);
108 }
109 
110 static void armsse_cpuid_class_init(ObjectClass *klass, void *data)
111 {
112     DeviceClass *dc = DEVICE_CLASS(klass);
113 
114     /*
115      * This device has no guest-modifiable state and so it
116      * does not need a reset function or VMState.
117      */
118 
119     device_class_set_props(dc, armsse_cpuid_props);
120 }
121 
122 static const TypeInfo armsse_cpuid_info = {
123     .name = TYPE_ARMSSE_CPUID,
124     .parent = TYPE_SYS_BUS_DEVICE,
125     .instance_size = sizeof(ARMSSECPUID),
126     .instance_init = armsse_cpuid_init,
127     .class_init = armsse_cpuid_class_init,
128 };
129 
130 static void armsse_cpuid_register_types(void)
131 {
132     type_register_static(&armsse_cpuid_info);
133 }
134 
135 type_init(armsse_cpuid_register_types);
136