xref: /openbmc/qemu/hw/misc/arm11scu.c (revision fee5b753)
1 /*
2  * ARM11MPCore Snoop Control Unit (SCU) emulation
3  *
4  * Copyright (c) 2006-2007 CodeSourcery.
5  * Copyright (c) 2013 SUSE LINUX Products GmbH
6  * Written by Paul Brook and Andreas Färber
7  *
8  * This code is licensed under the GPL.
9  */
10 
11 #include "qemu/osdep.h"
12 #include "hw/misc/arm11scu.h"
13 
14 static uint64_t mpcore_scu_read(void *opaque, hwaddr offset,
15                                 unsigned size)
16 {
17     ARM11SCUState *s = (ARM11SCUState *)opaque;
18     int id;
19     /* SCU */
20     switch (offset) {
21     case 0x00: /* Control.  */
22         return s->control;
23     case 0x04: /* Configuration.  */
24         id = ((1 << s->num_cpu) - 1) << 4;
25         return id | (s->num_cpu - 1);
26     case 0x08: /* CPU status.  */
27         return 0;
28     case 0x0c: /* Invalidate all.  */
29         return 0;
30     default:
31         qemu_log_mask(LOG_GUEST_ERROR,
32                       "mpcore_priv_read: Bad offset %x\n", (int)offset);
33         return 0;
34     }
35 }
36 
37 static void mpcore_scu_write(void *opaque, hwaddr offset,
38                              uint64_t value, unsigned size)
39 {
40     ARM11SCUState *s = (ARM11SCUState *)opaque;
41     /* SCU */
42     switch (offset) {
43     case 0: /* Control register.  */
44         s->control = value & 1;
45         break;
46     case 0x0c: /* Invalidate all.  */
47         /* This is a no-op as cache is not emulated.  */
48         break;
49     default:
50         qemu_log_mask(LOG_GUEST_ERROR,
51                       "mpcore_priv_read: Bad offset %x\n", (int)offset);
52     }
53 }
54 
55 static const MemoryRegionOps mpcore_scu_ops = {
56     .read = mpcore_scu_read,
57     .write = mpcore_scu_write,
58     .endianness = DEVICE_NATIVE_ENDIAN,
59 };
60 
61 static void arm11_scu_realize(DeviceState *dev, Error **errp)
62 {
63 }
64 
65 static void arm11_scu_init(Object *obj)
66 {
67     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
68     ARM11SCUState *s = ARM11_SCU(obj);
69 
70     memory_region_init_io(&s->iomem, OBJECT(s),
71                           &mpcore_scu_ops, s, "mpcore-scu", 0x100);
72     sysbus_init_mmio(sbd, &s->iomem);
73 }
74 
75 static Property arm11_scu_properties[] = {
76     DEFINE_PROP_UINT32("num-cpu", ARM11SCUState, num_cpu, 1),
77     DEFINE_PROP_END_OF_LIST()
78 };
79 
80 static void arm11_scu_class_init(ObjectClass *oc, void *data)
81 {
82     DeviceClass *dc = DEVICE_CLASS(oc);
83 
84     dc->realize = arm11_scu_realize;
85     dc->props = arm11_scu_properties;
86 }
87 
88 static const TypeInfo arm11_scu_type_info = {
89     .name          = TYPE_ARM11_SCU,
90     .parent        = TYPE_SYS_BUS_DEVICE,
91     .instance_size = sizeof(ARM11SCUState),
92     .instance_init = arm11_scu_init,
93     .class_init    = arm11_scu_class_init,
94 };
95 
96 static void arm11_scu_register_types(void)
97 {
98     type_register_static(&arm11_scu_type_info);
99 }
100 
101 type_init(arm11_scu_register_types)
102