xref: /openbmc/qemu/hw/intc/ompic.c (revision c00506aa)
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 OBJECT_DECLARE_SIMPLE_TYPE(OR1KOMPICState, OR1K_OMPIC)
22 
23 #define OMPIC_CTRL_IRQ_ACK  (1 << 31)
24 #define OMPIC_CTRL_IRQ_GEN  (1 << 30)
25 #define OMPIC_CTRL_DST(cpu) (((cpu) >> 16) & 0x3fff)
26 
27 #define OMPIC_REG(addr)     (((addr) >> 2) & 0x1)
28 #define OMPIC_SRC_CPU(addr) (((addr) >> 3) & 0x4f)
29 #define OMPIC_DST_CPU(addr) (((addr) >> 3) & 0x4f)
30 
31 #define OMPIC_STATUS_IRQ_PENDING (1 << 30)
32 #define OMPIC_STATUS_SRC(cpu)    (((cpu) & 0x3fff) << 16)
33 #define OMPIC_STATUS_DATA(data)  ((data) & 0xffff)
34 
35 #define OMPIC_CONTROL 0
36 #define OMPIC_STATUS  1
37 
38 #define OMPIC_MAX_CPUS 4 /* Real max is much higher, but dont waste memory */
39 #define OMPIC_ADDRSPACE_SZ (OMPIC_MAX_CPUS * 2 * 4) /* 2 32-bit regs per cpu */
40 
41 typedef struct OR1KOMPICCPUState OR1KOMPICCPUState;
42 
43 struct OR1KOMPICCPUState {
44     qemu_irq irq;
45     uint32_t status;
46     uint32_t control;
47 };
48 
49 struct OR1KOMPICState {
50     SysBusDevice parent_obj;
51     MemoryRegion mr;
52 
53     OR1KOMPICCPUState cpus[OMPIC_MAX_CPUS];
54 
55     uint32_t num_cpus;
56 };
57 
58 static uint64_t ompic_read(void *opaque, hwaddr addr, unsigned size)
59 {
60     OR1KOMPICState *s = opaque;
61     int src_cpu = OMPIC_SRC_CPU(addr);
62 
63     /* We can only write to control control, write control + update status */
64     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
65         return s->cpus[src_cpu].control;
66     } else {
67         return s->cpus[src_cpu].status;
68    }
69 
70 }
71 
72 static void ompic_write(void *opaque, hwaddr addr, uint64_t data, unsigned size)
73 {
74     OR1KOMPICState *s = opaque;
75     /* We can only write to control control, write control + update status */
76     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
77         int src_cpu = OMPIC_SRC_CPU(addr);
78 
79         s->cpus[src_cpu].control = data;
80 
81         if (data & OMPIC_CTRL_IRQ_GEN) {
82             int dst_cpu = OMPIC_CTRL_DST(data);
83 
84             s->cpus[dst_cpu].status = OMPIC_STATUS_IRQ_PENDING |
85                 OMPIC_STATUS_SRC(src_cpu) |
86                 OMPIC_STATUS_DATA(data);
87 
88             qemu_irq_raise(s->cpus[dst_cpu].irq);
89         }
90         if (data & OMPIC_CTRL_IRQ_ACK) {
91             s->cpus[src_cpu].status &= ~OMPIC_STATUS_IRQ_PENDING;
92             qemu_irq_lower(s->cpus[src_cpu].irq);
93         }
94     }
95 }
96 
97 static const MemoryRegionOps ompic_ops = {
98     .read = ompic_read,
99     .write = ompic_write,
100     .endianness = DEVICE_NATIVE_ENDIAN,
101     .impl = {
102         .max_access_size = 8,
103     },
104 };
105 
106 static void or1k_ompic_init(Object *obj)
107 {
108     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
109     OR1KOMPICState *s = OR1K_OMPIC(obj);
110 
111     memory_region_init_io(&s->mr, OBJECT(s), &ompic_ops, s,
112                           "or1k-ompic", OMPIC_ADDRSPACE_SZ);
113     sysbus_init_mmio(sbd, &s->mr);
114 }
115 
116 static void or1k_ompic_realize(DeviceState *dev, Error **errp)
117 {
118     OR1KOMPICState *s = OR1K_OMPIC(dev);
119     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
120     int i;
121 
122     if (s->num_cpus > OMPIC_MAX_CPUS) {
123         error_setg(errp, "Exceeded maximum CPUs %d", s->num_cpus);
124         return;
125     }
126     /* Init IRQ sources for all CPUs */
127     for (i = 0; i < s->num_cpus; i++) {
128         sysbus_init_irq(sbd, &s->cpus[i].irq);
129     }
130 }
131 
132 static Property or1k_ompic_properties[] = {
133     DEFINE_PROP_UINT32("num-cpus", OR1KOMPICState, num_cpus, 1),
134     DEFINE_PROP_END_OF_LIST(),
135 };
136 
137 static const VMStateDescription vmstate_or1k_ompic_cpu = {
138     .name = "or1k_ompic_cpu",
139     .version_id = 1,
140     .minimum_version_id = 1,
141     .fields = (VMStateField[]) {
142          VMSTATE_UINT32(status, OR1KOMPICCPUState),
143          VMSTATE_UINT32(control, OR1KOMPICCPUState),
144          VMSTATE_END_OF_LIST()
145     }
146 };
147 
148 static const VMStateDescription vmstate_or1k_ompic = {
149     .name = TYPE_OR1K_OMPIC,
150     .version_id = 1,
151     .minimum_version_id = 1,
152     .fields = (VMStateField[]) {
153          VMSTATE_STRUCT_ARRAY(cpus, OR1KOMPICState, OMPIC_MAX_CPUS, 1,
154              vmstate_or1k_ompic_cpu, OR1KOMPICCPUState),
155          VMSTATE_UINT32(num_cpus, OR1KOMPICState),
156          VMSTATE_END_OF_LIST()
157     }
158 };
159 
160 static void or1k_ompic_class_init(ObjectClass *klass, void *data)
161 {
162     DeviceClass *dc = DEVICE_CLASS(klass);
163 
164     device_class_set_props(dc, or1k_ompic_properties);
165     dc->realize = or1k_ompic_realize;
166     dc->vmsd = &vmstate_or1k_ompic;
167 }
168 
169 static const TypeInfo or1k_ompic_info = {
170     .name          = TYPE_OR1K_OMPIC,
171     .parent        = TYPE_SYS_BUS_DEVICE,
172     .instance_size = sizeof(OR1KOMPICState),
173     .instance_init = or1k_ompic_init,
174     .class_init    = or1k_ompic_class_init,
175 };
176 
177 static void or1k_ompic_register_types(void)
178 {
179     type_register_static(&or1k_ompic_info);
180 }
181 
182 type_init(or1k_ompic_register_types)
183