xref: /openbmc/qemu/hw/misc/mips_cpc.c (revision dc5bd18f)
1 /*
2  * Cluster Power Controller emulation
3  *
4  * Copyright (c) 2016 Imagination Technologies
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library 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 GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qapi/error.h"
22 #include "cpu.h"
23 #include "qemu/log.h"
24 #include "hw/sysbus.h"
25 
26 #include "hw/misc/mips_cpc.h"
27 
28 static inline uint64_t cpc_vp_run_mask(MIPSCPCState *cpc)
29 {
30     return (1ULL << cpc->num_vp) - 1;
31 }
32 
33 static void cpc_run_vp(MIPSCPCState *cpc, uint64_t vp_run)
34 {
35     CPUState *cs = first_cpu;
36 
37     CPU_FOREACH(cs) {
38         uint64_t i = 1ULL << cs->cpu_index;
39         if (i & vp_run & ~cpc->vp_running) {
40             cpu_reset(cs);
41             cpc->vp_running |= i;
42         }
43     }
44 }
45 
46 static void cpc_stop_vp(MIPSCPCState *cpc, uint64_t vp_stop)
47 {
48     CPUState *cs = first_cpu;
49 
50     CPU_FOREACH(cs) {
51         uint64_t i = 1ULL << cs->cpu_index;
52         if (i & vp_stop & cpc->vp_running) {
53             cpu_interrupt(cs, CPU_INTERRUPT_HALT);
54             cpc->vp_running &= ~i;
55         }
56     }
57 }
58 
59 static void cpc_write(void *opaque, hwaddr offset, uint64_t data,
60                       unsigned size)
61 {
62     MIPSCPCState *s = opaque;
63 
64     switch (offset) {
65     case CPC_CL_BASE_OFS + CPC_VP_RUN_OFS:
66     case CPC_CO_BASE_OFS + CPC_VP_RUN_OFS:
67         cpc_run_vp(s, data & cpc_vp_run_mask(s));
68         break;
69     case CPC_CL_BASE_OFS + CPC_VP_STOP_OFS:
70     case CPC_CO_BASE_OFS + CPC_VP_STOP_OFS:
71         cpc_stop_vp(s, data & cpc_vp_run_mask(s));
72         break;
73     default:
74         qemu_log_mask(LOG_UNIMP,
75                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
76         break;
77     }
78 
79     return;
80 }
81 
82 static uint64_t cpc_read(void *opaque, hwaddr offset, unsigned size)
83 {
84     MIPSCPCState *s = opaque;
85 
86     switch (offset) {
87     case CPC_CL_BASE_OFS + CPC_VP_RUNNING_OFS:
88     case CPC_CO_BASE_OFS + CPC_VP_RUNNING_OFS:
89         return s->vp_running;
90     default:
91         qemu_log_mask(LOG_UNIMP,
92                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
93         return 0;
94     }
95 }
96 
97 static const MemoryRegionOps cpc_ops = {
98     .read = cpc_read,
99     .write = cpc_write,
100     .endianness = DEVICE_NATIVE_ENDIAN,
101     .impl = {
102         .max_access_size = 8,
103     },
104 };
105 
106 static void mips_cpc_init(Object *obj)
107 {
108     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
109     MIPSCPCState *s = MIPS_CPC(obj);
110 
111     memory_region_init_io(&s->mr, OBJECT(s), &cpc_ops, s, "mips-cpc",
112                           CPC_ADDRSPACE_SZ);
113     sysbus_init_mmio(sbd, &s->mr);
114 }
115 
116 static void mips_cpc_realize(DeviceState *dev, Error **errp)
117 {
118     MIPSCPCState *s = MIPS_CPC(dev);
119 
120     if (s->vp_start_running > cpc_vp_run_mask(s)) {
121         error_setg(errp,
122                    "incorrect vp_start_running 0x%" PRIx64 " for num_vp = %d",
123                    s->vp_running, s->num_vp);
124         return;
125     }
126 }
127 
128 static void mips_cpc_reset(DeviceState *dev)
129 {
130     MIPSCPCState *s = MIPS_CPC(dev);
131 
132     /* Reflect the fact that all VPs are halted on reset */
133     s->vp_running = 0;
134 
135     /* Put selected VPs into run state */
136     cpc_run_vp(s, s->vp_start_running);
137 }
138 
139 static const VMStateDescription vmstate_mips_cpc = {
140     .name = "mips-cpc",
141     .version_id = 0,
142     .minimum_version_id = 0,
143     .fields = (VMStateField[]) {
144         VMSTATE_UINT64(vp_running, MIPSCPCState),
145         VMSTATE_END_OF_LIST()
146     },
147 };
148 
149 static Property mips_cpc_properties[] = {
150     DEFINE_PROP_UINT32("num-vp", MIPSCPCState, num_vp, 0x1),
151     DEFINE_PROP_UINT64("vp-start-running", MIPSCPCState, vp_start_running, 0x1),
152     DEFINE_PROP_END_OF_LIST(),
153 };
154 
155 static void mips_cpc_class_init(ObjectClass *klass, void *data)
156 {
157     DeviceClass *dc = DEVICE_CLASS(klass);
158 
159     dc->realize = mips_cpc_realize;
160     dc->reset = mips_cpc_reset;
161     dc->vmsd = &vmstate_mips_cpc;
162     dc->props = mips_cpc_properties;
163 }
164 
165 static const TypeInfo mips_cpc_info = {
166     .name          = TYPE_MIPS_CPC,
167     .parent        = TYPE_SYS_BUS_DEVICE,
168     .instance_size = sizeof(MIPSCPCState),
169     .instance_init = mips_cpc_init,
170     .class_init    = mips_cpc_class_init,
171 };
172 
173 static void mips_cpc_register_types(void)
174 {
175     type_register_static(&mips_cpc_info);
176 }
177 
178 type_init(mips_cpc_register_types)
179