xref: /openbmc/qemu/hw/intc/ompic.c (revision ba632924)
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 "qapi/error.h"
12 #include "hw/hw.h"
13 #include "hw/sysbus.h"
14 #include "exec/memory.h"
15 
16 #define TYPE_OR1K_OMPIC "or1k-ompic"
17 #define OR1K_OMPIC(obj) OBJECT_CHECK(OR1KOMPICState, (obj), TYPE_OR1K_OMPIC)
18 
19 #define OMPIC_CTRL_IRQ_ACK  (1 << 31)
20 #define OMPIC_CTRL_IRQ_GEN  (1 << 30)
21 #define OMPIC_CTRL_DST(cpu) (((cpu) >> 16) & 0x3fff)
22 
23 #define OMPIC_REG(addr)     (((addr) >> 2) & 0x1)
24 #define OMPIC_SRC_CPU(addr) (((addr) >> 3) & 0x4f)
25 #define OMPIC_DST_CPU(addr) (((addr) >> 3) & 0x4f)
26 
27 #define OMPIC_STATUS_IRQ_PENDING (1 << 30)
28 #define OMPIC_STATUS_SRC(cpu)    (((cpu) & 0x3fff) << 16)
29 #define OMPIC_STATUS_DATA(data)  ((data) & 0xffff)
30 
31 #define OMPIC_CONTROL 0
32 #define OMPIC_STATUS  1
33 
34 #define OMPIC_MAX_CPUS 4 /* Real max is much higher, but dont waste memory */
35 #define OMPIC_ADDRSPACE_SZ (OMPIC_MAX_CPUS * 2 * 4) /* 2 32-bit regs per cpu */
36 
37 typedef struct OR1KOMPICState OR1KOMPICState;
38 typedef struct OR1KOMPICCPUState OR1KOMPICCPUState;
39 
40 struct OR1KOMPICCPUState {
41     qemu_irq irq;
42     uint32_t status;
43     uint32_t control;
44 };
45 
46 struct OR1KOMPICState {
47     SysBusDevice parent_obj;
48     MemoryRegion mr;
49 
50     OR1KOMPICCPUState cpus[OMPIC_MAX_CPUS];
51 
52     uint32_t num_cpus;
53 };
54 
55 static uint64_t ompic_read(void *opaque, hwaddr addr, unsigned size)
56 {
57     OR1KOMPICState *s = opaque;
58     int src_cpu = OMPIC_SRC_CPU(addr);
59 
60     /* We can only write to control control, write control + update status */
61     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
62         return s->cpus[src_cpu].control;
63     } else {
64         return s->cpus[src_cpu].status;
65    }
66 
67 }
68 
69 static void ompic_write(void *opaque, hwaddr addr, uint64_t data, unsigned size)
70 {
71     OR1KOMPICState *s = opaque;
72     /* We can only write to control control, write control + update status */
73     if (OMPIC_REG(addr) == OMPIC_CONTROL) {
74         int src_cpu = OMPIC_SRC_CPU(addr);
75 
76         s->cpus[src_cpu].control = data;
77 
78         if (data & OMPIC_CTRL_IRQ_GEN) {
79             int dst_cpu = OMPIC_CTRL_DST(data);
80 
81             s->cpus[dst_cpu].status = OMPIC_STATUS_IRQ_PENDING |
82                 OMPIC_STATUS_SRC(src_cpu) |
83                 OMPIC_STATUS_DATA(data);
84 
85             qemu_irq_raise(s->cpus[dst_cpu].irq);
86         }
87         if (data & OMPIC_CTRL_IRQ_ACK) {
88             s->cpus[src_cpu].status &= ~OMPIC_STATUS_IRQ_PENDING;
89             qemu_irq_lower(s->cpus[src_cpu].irq);
90         }
91     }
92 }
93 
94 static const MemoryRegionOps ompic_ops = {
95     .read = ompic_read,
96     .write = ompic_write,
97     .endianness = DEVICE_NATIVE_ENDIAN,
98     .impl = {
99         .max_access_size = 8,
100     },
101 };
102 
103 static void or1k_ompic_init(Object *obj)
104 {
105     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
106     OR1KOMPICState *s = OR1K_OMPIC(obj);
107 
108     memory_region_init_io(&s->mr, OBJECT(s), &ompic_ops, s,
109                           "or1k-ompic", OMPIC_ADDRSPACE_SZ);
110     sysbus_init_mmio(sbd, &s->mr);
111 }
112 
113 static void or1k_ompic_realize(DeviceState *dev, Error **errp)
114 {
115     OR1KOMPICState *s = OR1K_OMPIC(dev);
116     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
117     int i;
118 
119     if (s->num_cpus > OMPIC_MAX_CPUS) {
120         error_setg(errp, "Exceeded maximum CPUs %d", s->num_cpus);
121         return;
122     }
123     /* Init IRQ sources for all CPUs */
124     for (i = 0; i < s->num_cpus; i++) {
125         sysbus_init_irq(sbd, &s->cpus[i].irq);
126     }
127 }
128 
129 static Property or1k_ompic_properties[] = {
130     DEFINE_PROP_UINT32("num-cpus", OR1KOMPICState, num_cpus, 1),
131     DEFINE_PROP_END_OF_LIST(),
132 };
133 
134 static const VMStateDescription vmstate_or1k_ompic_cpu = {
135     .name = "or1k_ompic_cpu",
136     .version_id = 1,
137     .minimum_version_id = 1,
138     .fields = (VMStateField[]) {
139          VMSTATE_UINT32(status, OR1KOMPICCPUState),
140          VMSTATE_UINT32(control, OR1KOMPICCPUState),
141          VMSTATE_END_OF_LIST()
142     }
143 };
144 
145 static const VMStateDescription vmstate_or1k_ompic = {
146     .name = TYPE_OR1K_OMPIC,
147     .version_id = 1,
148     .minimum_version_id = 1,
149     .fields = (VMStateField[]) {
150          VMSTATE_STRUCT_ARRAY(cpus, OR1KOMPICState, OMPIC_MAX_CPUS, 1,
151              vmstate_or1k_ompic_cpu, OR1KOMPICCPUState),
152          VMSTATE_UINT32(num_cpus, OR1KOMPICState),
153          VMSTATE_END_OF_LIST()
154     }
155 };
156 
157 static void or1k_ompic_class_init(ObjectClass *klass, void *data)
158 {
159     DeviceClass *dc = DEVICE_CLASS(klass);
160 
161     dc->props = or1k_ompic_properties;
162     dc->realize = or1k_ompic_realize;
163     dc->vmsd = &vmstate_or1k_ompic;
164 }
165 
166 static const TypeInfo or1k_ompic_info = {
167     .name          = TYPE_OR1K_OMPIC,
168     .parent        = TYPE_SYS_BUS_DEVICE,
169     .instance_size = sizeof(OR1KOMPICState),
170     .instance_init = or1k_ompic_init,
171     .class_init    = or1k_ompic_class_init,
172 };
173 
174 static void or1k_ompic_register_types(void)
175 {
176     type_register_static(&or1k_ompic_info);
177 }
178 
179 type_init(or1k_ompic_register_types)
180