xref: /openbmc/qemu/hw/cpu/cluster.c (revision f363d039)
1 /*
2  * QEMU CPU cluster
3  *
4  * Copyright (c) 2018 GreenSocs SAS
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version 2
9  * of the License, or (at your option) any later version.
10  *
11  * This program 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
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, see
18  * <http://www.gnu.org/licenses/gpl-2.0.html>
19  */
20 
21 #include "qemu/osdep.h"
22 #include "hw/cpu/cluster.h"
23 #include "hw/qdev-properties.h"
24 #include "hw/core/cpu.h"
25 #include "qapi/error.h"
26 #include "qemu/module.h"
27 #include "qemu/cutils.h"
28 
29 static Property cpu_cluster_properties[] = {
30     DEFINE_PROP_UINT32("cluster-id", CPUClusterState, cluster_id, 0),
31     DEFINE_PROP_END_OF_LIST()
32 };
33 
34 typedef struct CallbackData {
35     CPUClusterState *cluster;
36     int cpu_count;
37 } CallbackData;
38 
39 static int add_cpu_to_cluster(Object *obj, void *opaque)
40 {
41     CallbackData *cbdata = opaque;
42     CPUState *cpu = (CPUState *)object_dynamic_cast(obj, TYPE_CPU);
43 
44     if (cpu) {
45         cpu->cluster_index = cbdata->cluster->cluster_id;
46         cbdata->cpu_count++;
47     }
48     return 0;
49 }
50 
51 static void cpu_cluster_realize(DeviceState *dev, Error **errp)
52 {
53     /* Iterate through all our CPU children and set their cluster_index */
54     CPUClusterState *cluster = CPU_CLUSTER(dev);
55     Object *cluster_obj = OBJECT(dev);
56     CallbackData cbdata = {
57         .cluster = cluster,
58         .cpu_count = 0,
59     };
60 
61     if (cluster->cluster_id >= MAX_CLUSTERS) {
62         error_setg(errp, "cluster-id must be less than %d", MAX_CLUSTERS);
63         return;
64     }
65 
66     object_child_foreach_recursive(cluster_obj, add_cpu_to_cluster, &cbdata);
67 
68     /*
69      * A cluster with no CPUs is a bug in the board/SoC code that created it;
70      * if you hit this during development of new code, check that you have
71      * created the CPUs and parented them into the cluster object before
72      * realizing the cluster object.
73      */
74     assert(cbdata.cpu_count > 0);
75 }
76 
77 static void cpu_cluster_class_init(ObjectClass *klass, void *data)
78 {
79     DeviceClass *dc = DEVICE_CLASS(klass);
80 
81     dc->props = cpu_cluster_properties;
82     dc->realize = cpu_cluster_realize;
83 
84     /* This is not directly for users, CPU children must be attached by code */
85     dc->user_creatable = false;
86 }
87 
88 static const TypeInfo cpu_cluster_type_info = {
89     .name = TYPE_CPU_CLUSTER,
90     .parent = TYPE_DEVICE,
91     .instance_size = sizeof(CPUClusterState),
92     .class_init = cpu_cluster_class_init,
93 };
94 
95 static void cpu_cluster_register_types(void)
96 {
97     type_register_static(&cpu_cluster_type_info);
98 }
99 
100 type_init(cpu_cluster_register_types)
101