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 "qemu/module.h"
25#include "hw/sysbus.h"
26#include "migration/vmstate.h"
27
28#include "hw/misc/mips_cpc.h"
29#include "hw/qdev-properties.h"
30
31static inline uint64_t cpc_vp_run_mask(MIPSCPCState *cpc)
32{
33 return (1ULL << cpc->num_vp) - 1;
34}
35
36static void mips_cpu_reset_async_work(CPUState *cs, run_on_cpu_data data)
37{
38 MIPSCPCState *cpc = (MIPSCPCState *) data.host_ptr;
39
40 cpu_reset(cs);
41 cpc->vp_running |= 1ULL << cs->cpu_index;
42}
43
44static void cpc_run_vp(MIPSCPCState *cpc, uint64_t vp_run)
45{
46 CPUState *cs = first_cpu;
47
48 CPU_FOREACH(cs) {
49 uint64_t i = 1ULL << cs->cpu_index;
50 if (i & vp_run & ~cpc->vp_running) {
51 /*
52 * To avoid racing with a CPU we are just kicking off.
53 * We do the final bit of preparation for the work in
54 * the target CPUs context.
55 */
56 async_safe_run_on_cpu(cs, mips_cpu_reset_async_work,
57 RUN_ON_CPU_HOST_PTR(cpc));
58 }
59 }
60}
61
62static void cpc_stop_vp(MIPSCPCState *cpc, uint64_t vp_stop)
63{
64 CPUState *cs = first_cpu;
65
66 CPU_FOREACH(cs) {
67 uint64_t i = 1ULL << cs->cpu_index;
68 if (i & vp_stop & cpc->vp_running) {
69 cpu_interrupt(cs, CPU_INTERRUPT_HALT);
70 cpc->vp_running &= ~i;
71 }
72 }
73}
74
75static void cpc_write(void *opaque, hwaddr offset, uint64_t data,
76 unsigned size)
77{
78 MIPSCPCState *s = opaque;
79
80 switch (offset) {
81 case CPC_CL_BASE_OFS + CPC_VP_RUN_OFS:
82 case CPC_CO_BASE_OFS + CPC_VP_RUN_OFS:
83 cpc_run_vp(s, data & cpc_vp_run_mask(s));
84 break;
85 case CPC_CL_BASE_OFS + CPC_VP_STOP_OFS:
86 case CPC_CO_BASE_OFS + CPC_VP_STOP_OFS:
87 cpc_stop_vp(s, data & cpc_vp_run_mask(s));
88 break;
89 default:
90 qemu_log_mask(LOG_UNIMP,
91 "%s: Bad offset 0x%x\n", __func__, (int)offset);
92 break;
93 }
94
95 return;
96}
97
98static uint64_t cpc_read(void *opaque, hwaddr offset, unsigned size)
99{
100 MIPSCPCState *s = opaque;
101
102 switch (offset) {
103 case CPC_CL_BASE_OFS + CPC_VP_RUNNING_OFS:
104 case CPC_CO_BASE_OFS + CPC_VP_RUNNING_OFS:
105 return s->vp_running;
106 default:
107 qemu_log_mask(LOG_UNIMP,
108 "%s: Bad offset 0x%x\n", __func__, (int)offset);
109 return 0;
110 }
111}
112
113static const MemoryRegionOps cpc_ops = {
114 .read = cpc_read,
115 .write = cpc_write,
116 .endianness = DEVICE_NATIVE_ENDIAN,
117 .impl = {
118 .max_access_size = 8,
119 },
120};
121
122static void mips_cpc_init(Object *obj)
123{
124 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
125 MIPSCPCState *s = MIPS_CPC(obj);
126
127 memory_region_init_io(&s->mr, OBJECT(s), &cpc_ops, s, "mips-cpc",
128 CPC_ADDRSPACE_SZ);
129 sysbus_init_mmio(sbd, &s->mr);
130}
131
132static void mips_cpc_realize(DeviceState *dev, Error **errp)
133{
134 MIPSCPCState *s = MIPS_CPC(dev);
135
136 if (s->vp_start_running > cpc_vp_run_mask(s)) {
137 error_setg(errp,
138 "incorrect vp_start_running 0x%" PRIx64 " for num_vp = %d",
139 s->vp_running, s->num_vp);
140 return;
141 }
142}
143
144static void mips_cpc_reset(DeviceState *dev)
145{
146 MIPSCPCState *s = MIPS_CPC(dev);
147
148 /* Reflect the fact that all VPs are halted on reset */
149 s->vp_running = 0;
150
151 /* Put selected VPs into run state */
152 cpc_run_vp(s, s->vp_start_running);
153}
154
155static const VMStateDescription vmstate_mips_cpc = {
156 .name = "mips-cpc",
157 .version_id = 0,
158 .minimum_version_id = 0,
159 .fields = (VMStateField[]) {
160 VMSTATE_UINT64(vp_running, MIPSCPCState),
161 VMSTATE_END_OF_LIST()
162 },
163};
164
165static Property mips_cpc_properties[] = {
166 DEFINE_PROP_UINT32("num-vp", MIPSCPCState, num_vp, 0x1),
167 DEFINE_PROP_UINT64("vp-start-running", MIPSCPCState, vp_start_running, 0x1),
168 DEFINE_PROP_END_OF_LIST(),
169};
170
171static void mips_cpc_class_init(ObjectClass *klass, void *data)
172{
173 DeviceClass *dc = DEVICE_CLASS(klass);
174
175 dc->realize = mips_cpc_realize;
176 dc->reset = mips_cpc_reset;
177 dc->vmsd = &vmstate_mips_cpc;
178 dc->props = mips_cpc_properties;
179}
180
181static const TypeInfo mips_cpc_info = {
182 .name = TYPE_MIPS_CPC,
183 .parent = TYPE_SYS_BUS_DEVICE,
184 .instance_size = sizeof(MIPSCPCState),
185 .instance_init = mips_cpc_init,
186 .class_init = mips_cpc_class_init,
187};
188
189static void mips_cpc_register_types(void)
190{
191 type_register_static(&mips_cpc_info);
192}
193
194type_init(mips_cpc_register_types)
195