xref: /qemu/hw/cpu/cluster.c (revision e4a8e093dc74be049f4829831dce76e5edab0003)
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 
23 #include "hw/core/cpu.h"
24 #include "hw/cpu/cluster.h"
25 #include "hw/qdev-properties.h"
26 #include "qapi/error.h"
27 
28 static const Property cpu_cluster_properties[] = {
29     DEFINE_PROP_UINT32("cluster-id", CPUClusterState, cluster_id, 0),
30 };
31 
32 typedef struct CallbackData {
33     CPUClusterState *cluster;
34     int cpu_count;
35 } CallbackData;
36 
37 static int add_cpu_to_cluster(Object *obj, void *opaque)
38 {
39     CallbackData *cbdata = opaque;
40     CPUState *cpu = (CPUState *)object_dynamic_cast(obj, TYPE_CPU);
41 
42     if (cpu) {
43         cpu->cluster_index = cbdata->cluster->cluster_id;
44         cbdata->cpu_count++;
45     }
46     return 0;
47 }
48 
49 static void cpu_cluster_realize(DeviceState *dev, Error **errp)
50 {
51     /* Iterate through all our CPU children and set their cluster_index */
52     CPUClusterState *cluster = CPU_CLUSTER(dev);
53     Object *cluster_obj = OBJECT(dev);
54     CallbackData cbdata = {
55         .cluster = cluster,
56         .cpu_count = 0,
57     };
58 
59     if (cluster->cluster_id >= MAX_CLUSTERS) {
60         error_setg(errp, "cluster-id must be less than %d", MAX_CLUSTERS);
61         return;
62     }
63 
64     object_child_foreach_recursive(cluster_obj, add_cpu_to_cluster, &cbdata);
65 
66     /*
67      * A cluster with no CPUs is a bug in the board/SoC code that created it;
68      * if you hit this during development of new code, check that you have
69      * created the CPUs and parented them into the cluster object before
70      * realizing the cluster object.
71      */
72     assert(cbdata.cpu_count > 0);
73 }
74 
75 static void cpu_cluster_class_init(ObjectClass *klass, void *data)
76 {
77     DeviceClass *dc = DEVICE_CLASS(klass);
78 
79     device_class_set_props(dc, cpu_cluster_properties);
80     dc->realize = cpu_cluster_realize;
81 
82     /* This is not directly for users, CPU children must be attached by code */
83     dc->user_creatable = false;
84 }
85 
86 static const TypeInfo cpu_cluster_type_info = {
87     .name = TYPE_CPU_CLUSTER,
88     .parent = TYPE_DEVICE,
89     .instance_size = sizeof(CPUClusterState),
90     .class_init = cpu_cluster_class_init,
91 };
92 
93 static void cpu_cluster_register_types(void)
94 {
95     type_register_static(&cpu_cluster_type_info);
96 }
97 
98 type_init(cpu_cluster_register_types)
99