xref: /openbmc/qemu/hw/misc/armsse-cpu-pwrctrl.c (revision ed75658a)
1 /*
2  * Arm SSE CPU PWRCTRL register block
3  *
4  * Copyright (c) 2021 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<N>_PWRCTRL block" which is part of the
14  * Arm Corstone SSE-300 Example Subsystem and documented in
15  * https://developer.arm.com/documentation/101773/0000
16  */
17 
18 #include "qemu/osdep.h"
19 #include "qemu/log.h"
20 #include "qemu/module.h"
21 #include "trace.h"
22 #include "qapi/error.h"
23 #include "migration/vmstate.h"
24 #include "hw/sysbus.h"
25 #include "hw/registerfields.h"
26 #include "hw/misc/armsse-cpu-pwrctrl.h"
27 
28 REG32(CPUPWRCFG, 0x0)
29 REG32(PID4, 0xfd0)
30 REG32(PID5, 0xfd4)
31 REG32(PID6, 0xfd8)
32 REG32(PID7, 0xfdc)
33 REG32(PID0, 0xfe0)
34 REG32(PID1, 0xfe4)
35 REG32(PID2, 0xfe8)
36 REG32(PID3, 0xfec)
37 REG32(CID0, 0xff0)
38 REG32(CID1, 0xff4)
39 REG32(CID2, 0xff8)
40 REG32(CID3, 0xffc)
41 
42 /* PID/CID values */
43 static const int cpu_pwrctrl_id[] = {
44     0x04, 0x00, 0x00, 0x00, /* PID4..PID7 */
45     0x5a, 0xb8, 0x0b, 0x00, /* PID0..PID3 */
46     0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
47 };
48 
49 static uint64_t pwrctrl_read(void *opaque, hwaddr offset, unsigned size)
50 {
51     ARMSSECPUPwrCtrl *s = ARMSSE_CPU_PWRCTRL(opaque);
52     uint64_t r;
53 
54     switch (offset) {
55     case A_CPUPWRCFG:
56         r = s->cpupwrcfg;
57         break;
58     case A_PID4 ... A_CID3:
59         r = cpu_pwrctrl_id[(offset - A_PID4) / 4];
60         break;
61     default:
62         qemu_log_mask(LOG_GUEST_ERROR,
63                       "SSE CPU_PWRCTRL read: bad offset %x\n", (int)offset);
64         r = 0;
65         break;
66     }
67     trace_armsse_cpu_pwrctrl_read(offset, r, size);
68     return r;
69 }
70 
71 static void pwrctrl_write(void *opaque, hwaddr offset,
72                           uint64_t value, unsigned size)
73 {
74     ARMSSECPUPwrCtrl *s = ARMSSE_CPU_PWRCTRL(opaque);
75 
76     trace_armsse_cpu_pwrctrl_write(offset, value, size);
77 
78     switch (offset) {
79     case A_CPUPWRCFG:
80         qemu_log_mask(LOG_UNIMP,
81                       "SSE CPU_PWRCTRL: CPUPWRCFG unimplemented\n");
82         s->cpupwrcfg = value;
83         break;
84     default:
85         qemu_log_mask(LOG_GUEST_ERROR,
86                       "SSE CPU_PWRCTRL write: bad offset 0x%x\n", (int)offset);
87         break;
88     }
89 }
90 
91 static const MemoryRegionOps pwrctrl_ops = {
92     .read = pwrctrl_read,
93     .write = pwrctrl_write,
94     .endianness = DEVICE_LITTLE_ENDIAN,
95     .impl.min_access_size = 4,
96     .impl.max_access_size = 4,
97     .valid.min_access_size = 4,
98     .valid.max_access_size = 4,
99 };
100 
101 static void pwrctrl_reset(DeviceState *dev)
102 {
103     ARMSSECPUPwrCtrl *s = ARMSSE_CPU_PWRCTRL(dev);
104 
105     s->cpupwrcfg = 0;
106 }
107 
108 static const VMStateDescription pwrctrl_vmstate = {
109     .name = "armsse-cpu-pwrctrl",
110     .version_id = 1,
111     .minimum_version_id = 1,
112     .fields = (const VMStateField[]) {
113         VMSTATE_UINT32(cpupwrcfg, ARMSSECPUPwrCtrl),
114         VMSTATE_END_OF_LIST()
115     },
116 };
117 
118 static void pwrctrl_init(Object *obj)
119 {
120     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
121     ARMSSECPUPwrCtrl *s = ARMSSE_CPU_PWRCTRL(obj);
122 
123     memory_region_init_io(&s->iomem, obj, &pwrctrl_ops,
124                           s, "armsse-cpu-pwrctrl", 0x1000);
125     sysbus_init_mmio(sbd, &s->iomem);
126 }
127 
128 static void pwrctrl_class_init(ObjectClass *klass, void *data)
129 {
130     DeviceClass *dc = DEVICE_CLASS(klass);
131 
132     dc->reset = pwrctrl_reset;
133     dc->vmsd = &pwrctrl_vmstate;
134 }
135 
136 static const TypeInfo pwrctrl_info = {
137     .name = TYPE_ARMSSE_CPU_PWRCTRL,
138     .parent = TYPE_SYS_BUS_DEVICE,
139     .instance_size = sizeof(ARMSSECPUPwrCtrl),
140     .instance_init = pwrctrl_init,
141     .class_init = pwrctrl_class_init,
142 };
143 
144 static void pwrctrl_register_types(void)
145 {
146     type_register_static(&pwrctrl_info);
147 }
148 
149 type_init(pwrctrl_register_types);
150