xref: /openbmc/qemu/hw/misc/mips_cpc.c (revision 28ae3179fc52d2e4d870b635c4a412aab99759e7)
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 2.1 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  
cpc_vp_run_mask(MIPSCPCState * cpc)31  static inline uint64_t cpc_vp_run_mask(MIPSCPCState *cpc)
32  {
33      return (1ULL << cpc->num_vp) - 1;
34  }
35  
mips_cpu_reset_async_work(CPUState * cs,run_on_cpu_data data)36  static 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      cs->halted = 0;
42      cpc->vp_running |= 1ULL << cs->cpu_index;
43  }
44  
cpc_run_vp(MIPSCPCState * cpc,uint64_t vp_run)45  static void cpc_run_vp(MIPSCPCState *cpc, uint64_t vp_run)
46  {
47      CPUState *cs = first_cpu;
48  
49      CPU_FOREACH(cs) {
50          uint64_t i = 1ULL << cs->cpu_index;
51          if (i & vp_run & ~cpc->vp_running) {
52              /*
53               * To avoid racing with a CPU we are just kicking off.
54               * We do the final bit of preparation for the work in
55               * the target CPUs context.
56               */
57              async_safe_run_on_cpu(cs, mips_cpu_reset_async_work,
58                                    RUN_ON_CPU_HOST_PTR(cpc));
59          }
60      }
61  }
62  
cpc_stop_vp(MIPSCPCState * cpc,uint64_t vp_stop)63  static void cpc_stop_vp(MIPSCPCState *cpc, uint64_t vp_stop)
64  {
65      CPUState *cs = first_cpu;
66  
67      CPU_FOREACH(cs) {
68          uint64_t i = 1ULL << cs->cpu_index;
69          if (i & vp_stop & cpc->vp_running) {
70              cpu_interrupt(cs, CPU_INTERRUPT_HALT);
71              cpc->vp_running &= ~i;
72          }
73      }
74  }
75  
cpc_write(void * opaque,hwaddr offset,uint64_t data,unsigned size)76  static void cpc_write(void *opaque, hwaddr offset, uint64_t data,
77                        unsigned size)
78  {
79      MIPSCPCState *s = opaque;
80  
81      switch (offset) {
82      case CPC_CL_BASE_OFS + CPC_VP_RUN_OFS:
83      case CPC_CO_BASE_OFS + CPC_VP_RUN_OFS:
84          cpc_run_vp(s, data & cpc_vp_run_mask(s));
85          break;
86      case CPC_CL_BASE_OFS + CPC_VP_STOP_OFS:
87      case CPC_CO_BASE_OFS + CPC_VP_STOP_OFS:
88          cpc_stop_vp(s, data & cpc_vp_run_mask(s));
89          break;
90      default:
91          qemu_log_mask(LOG_UNIMP,
92                        "%s: Bad offset 0x%x\n",  __func__, (int)offset);
93          break;
94      }
95  
96      return;
97  }
98  
cpc_read(void * opaque,hwaddr offset,unsigned size)99  static uint64_t cpc_read(void *opaque, hwaddr offset, unsigned size)
100  {
101      MIPSCPCState *s = opaque;
102  
103      switch (offset) {
104      case CPC_CL_BASE_OFS + CPC_VP_RUNNING_OFS:
105      case CPC_CO_BASE_OFS + CPC_VP_RUNNING_OFS:
106          return s->vp_running;
107      default:
108          qemu_log_mask(LOG_UNIMP,
109                        "%s: Bad offset 0x%x\n",  __func__, (int)offset);
110          return 0;
111      }
112  }
113  
114  static const MemoryRegionOps cpc_ops = {
115      .read = cpc_read,
116      .write = cpc_write,
117      .endianness = DEVICE_NATIVE_ENDIAN,
118      .impl = {
119          .max_access_size = 8,
120      },
121  };
122  
mips_cpc_init(Object * obj)123  static void mips_cpc_init(Object *obj)
124  {
125      SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
126      MIPSCPCState *s = MIPS_CPC(obj);
127  
128      memory_region_init_io(&s->mr, OBJECT(s), &cpc_ops, s, "mips-cpc",
129                            CPC_ADDRSPACE_SZ);
130      sysbus_init_mmio(sbd, &s->mr);
131  }
132  
mips_cpc_realize(DeviceState * dev,Error ** errp)133  static void mips_cpc_realize(DeviceState *dev, Error **errp)
134  {
135      MIPSCPCState *s = MIPS_CPC(dev);
136  
137      if (s->vp_start_running > cpc_vp_run_mask(s)) {
138          error_setg(errp,
139                     "incorrect vp_start_running 0x%" PRIx64 " for num_vp = %d",
140                     s->vp_running, s->num_vp);
141          return;
142      }
143  }
144  
mips_cpc_reset(DeviceState * dev)145  static void mips_cpc_reset(DeviceState *dev)
146  {
147      MIPSCPCState *s = MIPS_CPC(dev);
148  
149      /* Reflect the fact that all VPs are halted on reset */
150      s->vp_running = 0;
151  
152      /* Put selected VPs into run state */
153      cpc_run_vp(s, s->vp_start_running);
154  }
155  
156  static const VMStateDescription vmstate_mips_cpc = {
157      .name = "mips-cpc",
158      .version_id = 0,
159      .minimum_version_id = 0,
160      .fields = (const VMStateField[]) {
161          VMSTATE_UINT64(vp_running, MIPSCPCState),
162          VMSTATE_END_OF_LIST()
163      },
164  };
165  
166  static Property mips_cpc_properties[] = {
167      DEFINE_PROP_UINT32("num-vp", MIPSCPCState, num_vp, 0x1),
168      DEFINE_PROP_UINT64("vp-start-running", MIPSCPCState, vp_start_running, 0x1),
169      DEFINE_PROP_END_OF_LIST(),
170  };
171  
mips_cpc_class_init(ObjectClass * klass,void * data)172  static void mips_cpc_class_init(ObjectClass *klass, void *data)
173  {
174      DeviceClass *dc = DEVICE_CLASS(klass);
175  
176      dc->realize = mips_cpc_realize;
177      device_class_set_legacy_reset(dc, mips_cpc_reset);
178      dc->vmsd = &vmstate_mips_cpc;
179      device_class_set_props(dc, mips_cpc_properties);
180  }
181  
182  static const TypeInfo mips_cpc_info = {
183      .name          = TYPE_MIPS_CPC,
184      .parent        = TYPE_SYS_BUS_DEVICE,
185      .instance_size = sizeof(MIPSCPCState),
186      .instance_init = mips_cpc_init,
187      .class_init    = mips_cpc_class_init,
188  };
189  
mips_cpc_register_types(void)190  static void mips_cpc_register_types(void)
191  {
192      type_register_static(&mips_cpc_info);
193  }
194  
195  type_init(mips_cpc_register_types)
196