xref: /openbmc/qemu/hw/misc/mips_cpc.c (revision 35658f6e)
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_interrupt(cs, CPU_INTERRUPT_WAKE);
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             cs->halted = 1;
54             cpu_reset_interrupt(cs, CPU_INTERRUPT_WAKE);
55             cpc->vp_running &= ~i;
56         }
57     }
58 }
59 
60 static void cpc_write(void *opaque, hwaddr offset, uint64_t data,
61                       unsigned size)
62 {
63     MIPSCPCState *s = opaque;
64 
65     switch (offset) {
66     case CPC_CL_BASE_OFS + CPC_VP_RUN_OFS:
67     case CPC_CO_BASE_OFS + CPC_VP_RUN_OFS:
68         cpc_run_vp(s, data & cpc_vp_run_mask(s));
69         break;
70     case CPC_CL_BASE_OFS + CPC_VP_STOP_OFS:
71     case CPC_CO_BASE_OFS + CPC_VP_STOP_OFS:
72         cpc_stop_vp(s, data & cpc_vp_run_mask(s));
73         break;
74     default:
75         qemu_log_mask(LOG_UNIMP,
76                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
77         break;
78     }
79 
80     return;
81 }
82 
83 static uint64_t cpc_read(void *opaque, hwaddr offset, unsigned size)
84 {
85     MIPSCPCState *s = opaque;
86 
87     switch (offset) {
88     case CPC_CL_BASE_OFS + CPC_VP_RUNNING_OFS:
89     case CPC_CO_BASE_OFS + CPC_VP_RUNNING_OFS:
90         return s->vp_running;
91     default:
92         qemu_log_mask(LOG_UNIMP,
93                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
94         return 0;
95     }
96 }
97 
98 static const MemoryRegionOps cpc_ops = {
99     .read = cpc_read,
100     .write = cpc_write,
101     .endianness = DEVICE_NATIVE_ENDIAN,
102     .impl = {
103         .max_access_size = 8,
104     },
105 };
106 
107 static void mips_cpc_init(Object *obj)
108 {
109     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
110     MIPSCPCState *s = MIPS_CPC(obj);
111 
112     memory_region_init_io(&s->mr, OBJECT(s), &cpc_ops, s, "mips-cpc",
113                           CPC_ADDRSPACE_SZ);
114     sysbus_init_mmio(sbd, &s->mr);
115 }
116 
117 static void mips_cpc_realize(DeviceState *dev, Error **errp)
118 {
119     MIPSCPCState *s = MIPS_CPC(dev);
120 
121     if (s->vp_start_running > cpc_vp_run_mask(s)) {
122         error_setg(errp,
123                    "incorrect vp_start_running 0x%" PRIx64 " for num_vp = %d",
124                    s->vp_running, s->num_vp);
125         return;
126     }
127 }
128 
129 static void mips_cpc_reset(DeviceState *dev)
130 {
131     MIPSCPCState *s = MIPS_CPC(dev);
132 
133     /* Reflect the fact that all VPs are halted on reset */
134     s->vp_running = 0;
135 
136     /* Put selected VPs into run state */
137     cpc_run_vp(s, s->vp_start_running);
138 }
139 
140 static const VMStateDescription vmstate_mips_cpc = {
141     .name = "mips-cpc",
142     .version_id = 0,
143     .minimum_version_id = 0,
144     .fields = (VMStateField[]) {
145         VMSTATE_UINT64(vp_running, MIPSCPCState),
146         VMSTATE_END_OF_LIST()
147     },
148 };
149 
150 static Property mips_cpc_properties[] = {
151     DEFINE_PROP_UINT32("num-vp", MIPSCPCState, num_vp, 0x1),
152     DEFINE_PROP_UINT64("vp-start-running", MIPSCPCState, vp_start_running, 0x1),
153     DEFINE_PROP_END_OF_LIST(),
154 };
155 
156 static void mips_cpc_class_init(ObjectClass *klass, void *data)
157 {
158     DeviceClass *dc = DEVICE_CLASS(klass);
159 
160     dc->realize = mips_cpc_realize;
161     dc->reset = mips_cpc_reset;
162     dc->vmsd = &vmstate_mips_cpc;
163     dc->props = mips_cpc_properties;
164 }
165 
166 static const TypeInfo mips_cpc_info = {
167     .name          = TYPE_MIPS_CPC,
168     .parent        = TYPE_SYS_BUS_DEVICE,
169     .instance_size = sizeof(MIPSCPCState),
170     .instance_init = mips_cpc_init,
171     .class_init    = mips_cpc_class_init,
172 };
173 
174 static void mips_cpc_register_types(void)
175 {
176     type_register_static(&mips_cpc_info);
177 }
178 
179 type_init(mips_cpc_register_types)
180