xref: /openbmc/qemu/hw/intc/ompic.c (revision e84328fa)
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/hw.h"
14 #include "hw/sysbus.h"
15 #include "exec/memory.h"
16 
17 #define TYPE_OR1K_OMPIC "or1k-ompic"
18 #define OR1K_OMPIC(obj) OBJECT_CHECK(OR1KOMPICState, (obj), TYPE_OR1K_OMPIC)
19 
20 #define OMPIC_CTRL_IRQ_ACK  (1 << 31)
21 #define OMPIC_CTRL_IRQ_GEN  (1 << 30)
22 #define OMPIC_CTRL_DST(cpu) (((cpu) >> 16) & 0x3fff)
23 
24 #define OMPIC_REG(addr)     (((addr) >> 2) & 0x1)
25 #define OMPIC_SRC_CPU(addr) (((addr) >> 3) & 0x4f)
26 #define OMPIC_DST_CPU(addr) (((addr) >> 3) & 0x4f)
27 
28 #define OMPIC_STATUS_IRQ_PENDING (1 << 30)
29 #define OMPIC_STATUS_SRC(cpu)    (((cpu) & 0x3fff) << 16)
30 #define OMPIC_STATUS_DATA(data)  ((data) & 0xffff)
31 
32 #define OMPIC_CONTROL 0
33 #define OMPIC_STATUS  1
34 
35 #define OMPIC_MAX_CPUS 4 /* Real max is much higher, but dont waste memory */
36 #define OMPIC_ADDRSPACE_SZ (OMPIC_MAX_CPUS * 2 * 4) /* 2 32-bit regs per cpu */
37 
38 typedef struct OR1KOMPICState OR1KOMPICState;
39 typedef struct OR1KOMPICCPUState OR1KOMPICCPUState;
40 
41 struct OR1KOMPICCPUState {
42     qemu_irq irq;
43     uint32_t status;
44     uint32_t control;
45 };
46 
47 struct OR1KOMPICState {
48     SysBusDevice parent_obj;
49     MemoryRegion mr;
50 
51     OR1KOMPICCPUState cpus[OMPIC_MAX_CPUS];
52 
53     uint32_t num_cpus;
54 };
55 
56 static uint64_t ompic_read(void *opaque, hwaddr addr, unsigned size)
57 {
58     OR1KOMPICState *s = opaque;
59     int src_cpu = OMPIC_SRC_CPU(addr);
60 
61     /* We can only write to control control, write control + update status */
62     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
63         return s->cpus[src_cpu].control;
64     } else {
65         return s->cpus[src_cpu].status;
66    }
67 
68 }
69 
70 static void ompic_write(void *opaque, hwaddr addr, uint64_t data, unsigned size)
71 {
72     OR1KOMPICState *s = opaque;
73     /* We can only write to control control, write control + update status */
74     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
75         int src_cpu = OMPIC_SRC_CPU(addr);
76 
77         s->cpus[src_cpu].control = data;
78 
79         if (data & OMPIC_CTRL_IRQ_GEN) {
80             int dst_cpu = OMPIC_CTRL_DST(data);
81 
82             s->cpus[dst_cpu].status = OMPIC_STATUS_IRQ_PENDING |
83                 OMPIC_STATUS_SRC(src_cpu) |
84                 OMPIC_STATUS_DATA(data);
85 
86             qemu_irq_raise(s->cpus[dst_cpu].irq);
87         }
88         if (data & OMPIC_CTRL_IRQ_ACK) {
89             s->cpus[src_cpu].status &= ~OMPIC_STATUS_IRQ_PENDING;
90             qemu_irq_lower(s->cpus[src_cpu].irq);
91         }
92     }
93 }
94 
95 static const MemoryRegionOps ompic_ops = {
96     .read = ompic_read,
97     .write = ompic_write,
98     .endianness = DEVICE_NATIVE_ENDIAN,
99     .impl = {
100         .max_access_size = 8,
101     },
102 };
103 
104 static void or1k_ompic_init(Object *obj)
105 {
106     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
107     OR1KOMPICState *s = OR1K_OMPIC(obj);
108 
109     memory_region_init_io(&s->mr, OBJECT(s), &ompic_ops, s,
110                           "or1k-ompic", OMPIC_ADDRSPACE_SZ);
111     sysbus_init_mmio(sbd, &s->mr);
112 }
113 
114 static void or1k_ompic_realize(DeviceState *dev, Error **errp)
115 {
116     OR1KOMPICState *s = OR1K_OMPIC(dev);
117     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
118     int i;
119 
120     if (s->num_cpus > OMPIC_MAX_CPUS) {
121         error_setg(errp, "Exceeded maximum CPUs %d", s->num_cpus);
122         return;
123     }
124     /* Init IRQ sources for all CPUs */
125     for (i = 0; i < s->num_cpus; i++) {
126         sysbus_init_irq(sbd, &s->cpus[i].irq);
127     }
128 }
129 
130 static Property or1k_ompic_properties[] = {
131     DEFINE_PROP_UINT32("num-cpus", OR1KOMPICState, num_cpus, 1),
132     DEFINE_PROP_END_OF_LIST(),
133 };
134 
135 static const VMStateDescription vmstate_or1k_ompic_cpu = {
136     .name = "or1k_ompic_cpu",
137     .version_id = 1,
138     .minimum_version_id = 1,
139     .fields = (VMStateField[]) {
140          VMSTATE_UINT32(status, OR1KOMPICCPUState),
141          VMSTATE_UINT32(control, OR1KOMPICCPUState),
142          VMSTATE_END_OF_LIST()
143     }
144 };
145 
146 static const VMStateDescription vmstate_or1k_ompic = {
147     .name = TYPE_OR1K_OMPIC,
148     .version_id = 1,
149     .minimum_version_id = 1,
150     .fields = (VMStateField[]) {
151          VMSTATE_STRUCT_ARRAY(cpus, OR1KOMPICState, OMPIC_MAX_CPUS, 1,
152              vmstate_or1k_ompic_cpu, OR1KOMPICCPUState),
153          VMSTATE_UINT32(num_cpus, OR1KOMPICState),
154          VMSTATE_END_OF_LIST()
155     }
156 };
157 
158 static void or1k_ompic_class_init(ObjectClass *klass, void *data)
159 {
160     DeviceClass *dc = DEVICE_CLASS(klass);
161 
162     dc->props = or1k_ompic_properties;
163     dc->realize = or1k_ompic_realize;
164     dc->vmsd = &vmstate_or1k_ompic;
165 }
166 
167 static const TypeInfo or1k_ompic_info = {
168     .name          = TYPE_OR1K_OMPIC,
169     .parent        = TYPE_SYS_BUS_DEVICE,
170     .instance_size = sizeof(OR1KOMPICState),
171     .instance_init = or1k_ompic_init,
172     .class_init    = or1k_ompic_class_init,
173 };
174 
175 static void or1k_ompic_register_types(void)
176 {
177     type_register_static(&or1k_ompic_info);
178 }
179 
180 type_init(or1k_ompic_register_types)
181