xref: /openbmc/qemu/hw/misc/arm11scu.c (revision 37677d7d)
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 #include "qemu/log.h"
14 #include "qemu/module.h"
15 
16 static uint64_t mpcore_scu_read(void *opaque, hwaddr offset,
17                                 unsigned size)
18 {
19     ARM11SCUState *s = (ARM11SCUState *)opaque;
20     int id;
21     /* SCU */
22     switch (offset) {
23     case 0x00: /* Control.  */
24         return s->control;
25     case 0x04: /* Configuration.  */
26         id = ((1 << s->num_cpu) - 1) << 4;
27         return id | (s->num_cpu - 1);
28     case 0x08: /* CPU status.  */
29         return 0;
30     case 0x0c: /* Invalidate all.  */
31         return 0;
32     default:
33         qemu_log_mask(LOG_GUEST_ERROR,
34                       "mpcore_priv_read: Bad offset %x\n", (int)offset);
35         return 0;
36     }
37 }
38 
39 static void mpcore_scu_write(void *opaque, hwaddr offset,
40                              uint64_t value, unsigned size)
41 {
42     ARM11SCUState *s = (ARM11SCUState *)opaque;
43     /* SCU */
44     switch (offset) {
45     case 0: /* Control register.  */
46         s->control = value & 1;
47         break;
48     case 0x0c: /* Invalidate all.  */
49         /* This is a no-op as cache is not emulated.  */
50         break;
51     default:
52         qemu_log_mask(LOG_GUEST_ERROR,
53                       "mpcore_priv_read: Bad offset %x\n", (int)offset);
54     }
55 }
56 
57 static const MemoryRegionOps mpcore_scu_ops = {
58     .read = mpcore_scu_read,
59     .write = mpcore_scu_write,
60     .endianness = DEVICE_NATIVE_ENDIAN,
61 };
62 
63 static void arm11_scu_realize(DeviceState *dev, Error **errp)
64 {
65 }
66 
67 static void arm11_scu_init(Object *obj)
68 {
69     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
70     ARM11SCUState *s = ARM11_SCU(obj);
71 
72     memory_region_init_io(&s->iomem, OBJECT(s),
73                           &mpcore_scu_ops, s, "mpcore-scu", 0x100);
74     sysbus_init_mmio(sbd, &s->iomem);
75 }
76 
77 static Property arm11_scu_properties[] = {
78     DEFINE_PROP_UINT32("num-cpu", ARM11SCUState, num_cpu, 1),
79     DEFINE_PROP_END_OF_LIST()
80 };
81 
82 static void arm11_scu_class_init(ObjectClass *oc, void *data)
83 {
84     DeviceClass *dc = DEVICE_CLASS(oc);
85 
86     dc->realize = arm11_scu_realize;
87     dc->props = arm11_scu_properties;
88 }
89 
90 static const TypeInfo arm11_scu_type_info = {
91     .name          = TYPE_ARM11_SCU,
92     .parent        = TYPE_SYS_BUS_DEVICE,
93     .instance_size = sizeof(ARM11SCUState),
94     .instance_init = arm11_scu_init,
95     .class_init    = arm11_scu_class_init,
96 };
97 
98 static void arm11_scu_register_types(void)
99 {
100     type_register_static(&arm11_scu_type_info);
101 }
102 
103 type_init(arm11_scu_register_types)
104