xref: /openbmc/qemu/hw/intc/ompic.c (revision a68694cd)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Authors: Stafford Horne <shorne@gmail.com>
7  */
8 
9 #include "qemu/osdep.h"
10 #include "qemu/log.h"
11 #include "qemu/module.h"
12 #include "qapi/error.h"
13 #include "hw/irq.h"
14 #include "hw/qdev-properties.h"
15 #include "hw/sysbus.h"
16 #include "migration/vmstate.h"
17 #include "exec/memory.h"
18 #include "qom/object.h"
19 
20 #define TYPE_OR1K_OMPIC "or1k-ompic"
21 typedef struct OR1KOMPICState OR1KOMPICState;
22 DECLARE_INSTANCE_CHECKER(OR1KOMPICState, OR1K_OMPIC,
23                          TYPE_OR1K_OMPIC)
24 
25 #define OMPIC_CTRL_IRQ_ACK  (1 << 31)
26 #define OMPIC_CTRL_IRQ_GEN  (1 << 30)
27 #define OMPIC_CTRL_DST(cpu) (((cpu) >> 16) & 0x3fff)
28 
29 #define OMPIC_REG(addr)     (((addr) >> 2) & 0x1)
30 #define OMPIC_SRC_CPU(addr) (((addr) >> 3) & 0x4f)
31 #define OMPIC_DST_CPU(addr) (((addr) >> 3) & 0x4f)
32 
33 #define OMPIC_STATUS_IRQ_PENDING (1 << 30)
34 #define OMPIC_STATUS_SRC(cpu)    (((cpu) & 0x3fff) << 16)
35 #define OMPIC_STATUS_DATA(data)  ((data) & 0xffff)
36 
37 #define OMPIC_CONTROL 0
38 #define OMPIC_STATUS  1
39 
40 #define OMPIC_MAX_CPUS 4 /* Real max is much higher, but dont waste memory */
41 #define OMPIC_ADDRSPACE_SZ (OMPIC_MAX_CPUS * 2 * 4) /* 2 32-bit regs per cpu */
42 
43 typedef struct OR1KOMPICCPUState OR1KOMPICCPUState;
44 
45 struct OR1KOMPICCPUState {
46     qemu_irq irq;
47     uint32_t status;
48     uint32_t control;
49 };
50 
51 struct OR1KOMPICState {
52     SysBusDevice parent_obj;
53     MemoryRegion mr;
54 
55     OR1KOMPICCPUState cpus[OMPIC_MAX_CPUS];
56 
57     uint32_t num_cpus;
58 };
59 
60 static uint64_t ompic_read(void *opaque, hwaddr addr, unsigned size)
61 {
62     OR1KOMPICState *s = opaque;
63     int src_cpu = OMPIC_SRC_CPU(addr);
64 
65     /* We can only write to control control, write control + update status */
66     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
67         return s->cpus[src_cpu].control;
68     } else {
69         return s->cpus[src_cpu].status;
70    }
71 
72 }
73 
74 static void ompic_write(void *opaque, hwaddr addr, uint64_t data, unsigned size)
75 {
76     OR1KOMPICState *s = opaque;
77     /* We can only write to control control, write control + update status */
78     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
79         int src_cpu = OMPIC_SRC_CPU(addr);
80 
81         s->cpus[src_cpu].control = data;
82 
83         if (data & OMPIC_CTRL_IRQ_GEN) {
84             int dst_cpu = OMPIC_CTRL_DST(data);
85 
86             s->cpus[dst_cpu].status = OMPIC_STATUS_IRQ_PENDING |
87                 OMPIC_STATUS_SRC(src_cpu) |
88                 OMPIC_STATUS_DATA(data);
89 
90             qemu_irq_raise(s->cpus[dst_cpu].irq);
91         }
92         if (data & OMPIC_CTRL_IRQ_ACK) {
93             s->cpus[src_cpu].status &= ~OMPIC_STATUS_IRQ_PENDING;
94             qemu_irq_lower(s->cpus[src_cpu].irq);
95         }
96     }
97 }
98 
99 static const MemoryRegionOps ompic_ops = {
100     .read = ompic_read,
101     .write = ompic_write,
102     .endianness = DEVICE_NATIVE_ENDIAN,
103     .impl = {
104         .max_access_size = 8,
105     },
106 };
107 
108 static void or1k_ompic_init(Object *obj)
109 {
110     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
111     OR1KOMPICState *s = OR1K_OMPIC(obj);
112 
113     memory_region_init_io(&s->mr, OBJECT(s), &ompic_ops, s,
114                           "or1k-ompic", OMPIC_ADDRSPACE_SZ);
115     sysbus_init_mmio(sbd, &s->mr);
116 }
117 
118 static void or1k_ompic_realize(DeviceState *dev, Error **errp)
119 {
120     OR1KOMPICState *s = OR1K_OMPIC(dev);
121     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
122     int i;
123 
124     if (s->num_cpus > OMPIC_MAX_CPUS) {
125         error_setg(errp, "Exceeded maximum CPUs %d", s->num_cpus);
126         return;
127     }
128     /* Init IRQ sources for all CPUs */
129     for (i = 0; i < s->num_cpus; i++) {
130         sysbus_init_irq(sbd, &s->cpus[i].irq);
131     }
132 }
133 
134 static Property or1k_ompic_properties[] = {
135     DEFINE_PROP_UINT32("num-cpus", OR1KOMPICState, num_cpus, 1),
136     DEFINE_PROP_END_OF_LIST(),
137 };
138 
139 static const VMStateDescription vmstate_or1k_ompic_cpu = {
140     .name = "or1k_ompic_cpu",
141     .version_id = 1,
142     .minimum_version_id = 1,
143     .fields = (VMStateField[]) {
144          VMSTATE_UINT32(status, OR1KOMPICCPUState),
145          VMSTATE_UINT32(control, OR1KOMPICCPUState),
146          VMSTATE_END_OF_LIST()
147     }
148 };
149 
150 static const VMStateDescription vmstate_or1k_ompic = {
151     .name = TYPE_OR1K_OMPIC,
152     .version_id = 1,
153     .minimum_version_id = 1,
154     .fields = (VMStateField[]) {
155          VMSTATE_STRUCT_ARRAY(cpus, OR1KOMPICState, OMPIC_MAX_CPUS, 1,
156              vmstate_or1k_ompic_cpu, OR1KOMPICCPUState),
157          VMSTATE_UINT32(num_cpus, OR1KOMPICState),
158          VMSTATE_END_OF_LIST()
159     }
160 };
161 
162 static void or1k_ompic_class_init(ObjectClass *klass, void *data)
163 {
164     DeviceClass *dc = DEVICE_CLASS(klass);
165 
166     device_class_set_props(dc, or1k_ompic_properties);
167     dc->realize = or1k_ompic_realize;
168     dc->vmsd = &vmstate_or1k_ompic;
169 }
170 
171 static const TypeInfo or1k_ompic_info = {
172     .name          = TYPE_OR1K_OMPIC,
173     .parent        = TYPE_SYS_BUS_DEVICE,
174     .instance_size = sizeof(OR1KOMPICState),
175     .instance_init = or1k_ompic_init,
176     .class_init    = or1k_ompic_class_init,
177 };
178 
179 static void or1k_ompic_register_types(void)
180 {
181     type_register_static(&or1k_ompic_info);
182 }
183 
184 type_init(or1k_ompic_register_types)
185