xref: /openbmc/qemu/hw/misc/mips_cpc.c (revision d9d3aaea)
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 "hw/sysbus.h"
23 
24 #include "hw/misc/mips_cpc.h"
25 
26 static inline uint64_t cpc_vp_run_mask(MIPSCPCState *cpc)
27 {
28     return (1ULL << cpc->num_vp) - 1;
29 }
30 
31 static void cpc_run_vp(MIPSCPCState *cpc, uint64_t vp_run)
32 {
33     CPUState *cs = first_cpu;
34 
35     CPU_FOREACH(cs) {
36         uint64_t i = 1ULL << cs->cpu_index;
37         if (i & vp_run & ~cpc->vp_running) {
38             cpu_interrupt(cs, CPU_INTERRUPT_WAKE);
39             cpc->vp_running |= i;
40         }
41     }
42 }
43 
44 static void cpc_stop_vp(MIPSCPCState *cpc, uint64_t vp_stop)
45 {
46     CPUState *cs = first_cpu;
47 
48     CPU_FOREACH(cs) {
49         uint64_t i = 1ULL << cs->cpu_index;
50         if (i & vp_stop & cpc->vp_running) {
51             cs->halted = 1;
52             cpu_reset_interrupt(cs, CPU_INTERRUPT_WAKE);
53             cpc->vp_running &= ~i;
54         }
55     }
56 }
57 
58 static void cpc_write(void *opaque, hwaddr offset, uint64_t data,
59                       unsigned size)
60 {
61     MIPSCPCState *s = opaque;
62 
63     switch (offset) {
64     case CPC_CL_BASE_OFS + CPC_VP_RUN_OFS:
65     case CPC_CO_BASE_OFS + CPC_VP_RUN_OFS:
66         cpc_run_vp(s, data & cpc_vp_run_mask(s));
67         break;
68     case CPC_CL_BASE_OFS + CPC_VP_STOP_OFS:
69     case CPC_CO_BASE_OFS + CPC_VP_STOP_OFS:
70         cpc_stop_vp(s, data & cpc_vp_run_mask(s));
71         break;
72     default:
73         qemu_log_mask(LOG_UNIMP,
74                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
75         break;
76     }
77 
78     return;
79 }
80 
81 static uint64_t cpc_read(void *opaque, hwaddr offset, unsigned size)
82 {
83     MIPSCPCState *s = opaque;
84 
85     switch (offset) {
86     case CPC_CL_BASE_OFS + CPC_VP_RUNNING_OFS:
87     case CPC_CO_BASE_OFS + CPC_VP_RUNNING_OFS:
88         return s->vp_running;
89     default:
90         qemu_log_mask(LOG_UNIMP,
91                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
92         return 0;
93     }
94 }
95 
96 static const MemoryRegionOps cpc_ops = {
97     .read = cpc_read,
98     .write = cpc_write,
99     .endianness = DEVICE_NATIVE_ENDIAN,
100     .impl = {
101         .max_access_size = 8,
102     },
103 };
104 
105 static void mips_cpc_init(Object *obj)
106 {
107     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
108     MIPSCPCState *s = MIPS_CPC(obj);
109 
110     memory_region_init_io(&s->mr, OBJECT(s), &cpc_ops, s, "mips-cpc",
111                           CPC_ADDRSPACE_SZ);
112     sysbus_init_mmio(sbd, &s->mr);
113 }
114 
115 static void mips_cpc_realize(DeviceState *dev, Error **errp)
116 {
117     MIPSCPCState *s = MIPS_CPC(dev);
118 
119     if (s->vp_start_running > cpc_vp_run_mask(s)) {
120         error_setg(errp,
121                    "incorrect vp_start_running 0x%" PRIx64 " for num_vp = %d",
122                    s->vp_running, s->num_vp);
123         return;
124     }
125 }
126 
127 static void mips_cpc_reset(DeviceState *dev)
128 {
129     MIPSCPCState *s = MIPS_CPC(dev);
130 
131     /* Reflect the fact that all VPs are halted on reset */
132     s->vp_running = 0;
133 
134     /* Put selected VPs into run state */
135     cpc_run_vp(s, s->vp_start_running);
136 }
137 
138 static const VMStateDescription vmstate_mips_cpc = {
139     .name = "mips-cpc",
140     .version_id = 0,
141     .minimum_version_id = 0,
142     .fields = (VMStateField[]) {
143         VMSTATE_UINT64(vp_running, MIPSCPCState),
144         VMSTATE_END_OF_LIST()
145     },
146 };
147 
148 static Property mips_cpc_properties[] = {
149     DEFINE_PROP_UINT32("num-vp", MIPSCPCState, num_vp, 0x1),
150     DEFINE_PROP_UINT64("vp-start-running", MIPSCPCState, vp_start_running, 0x1),
151     DEFINE_PROP_END_OF_LIST(),
152 };
153 
154 static void mips_cpc_class_init(ObjectClass *klass, void *data)
155 {
156     DeviceClass *dc = DEVICE_CLASS(klass);
157 
158     dc->realize = mips_cpc_realize;
159     dc->reset = mips_cpc_reset;
160     dc->vmsd = &vmstate_mips_cpc;
161     dc->props = mips_cpc_properties;
162 }
163 
164 static const TypeInfo mips_cpc_info = {
165     .name          = TYPE_MIPS_CPC,
166     .parent        = TYPE_SYS_BUS_DEVICE,
167     .instance_size = sizeof(MIPSCPCState),
168     .instance_init = mips_cpc_init,
169     .class_init    = mips_cpc_class_init,
170 };
171 
172 static void mips_cpc_register_types(void)
173 {
174     type_register_static(&mips_cpc_info);
175 }
176 
177 type_init(mips_cpc_register_types)
178