xref: /openbmc/qemu/hw/misc/arm11scu.c (revision 14a650ec)
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 "hw/misc/arm11scu.h"
12 
13 static uint64_t mpcore_scu_read(void *opaque, hwaddr offset,
14                                 unsigned size)
15 {
16     ARM11SCUState *s = (ARM11SCUState *)opaque;
17     int id;
18     /* SCU */
19     switch (offset) {
20     case 0x00: /* Control.  */
21         return s->control;
22     case 0x04: /* Configuration.  */
23         id = ((1 << s->num_cpu) - 1) << 4;
24         return id | (s->num_cpu - 1);
25     case 0x08: /* CPU status.  */
26         return 0;
27     case 0x0c: /* Invalidate all.  */
28         return 0;
29     default:
30         qemu_log_mask(LOG_GUEST_ERROR,
31                       "mpcore_priv_read: Bad offset %x\n", (int)offset);
32         return 0;
33     }
34 }
35 
36 static void mpcore_scu_write(void *opaque, hwaddr offset,
37                              uint64_t value, unsigned size)
38 {
39     ARM11SCUState *s = (ARM11SCUState *)opaque;
40     /* SCU */
41     switch (offset) {
42     case 0: /* Control register.  */
43         s->control = value & 1;
44         break;
45     case 0x0c: /* Invalidate all.  */
46         /* This is a no-op as cache is not emulated.  */
47         break;
48     default:
49         qemu_log_mask(LOG_GUEST_ERROR,
50                       "mpcore_priv_read: Bad offset %x\n", (int)offset);
51     }
52 }
53 
54 static const MemoryRegionOps mpcore_scu_ops = {
55     .read = mpcore_scu_read,
56     .write = mpcore_scu_write,
57     .endianness = DEVICE_NATIVE_ENDIAN,
58 };
59 
60 static void arm11_scu_realize(DeviceState *dev, Error **errp)
61 {
62 }
63 
64 static void arm11_scu_init(Object *obj)
65 {
66     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
67     ARM11SCUState *s = ARM11_SCU(obj);
68 
69     memory_region_init_io(&s->iomem, OBJECT(s),
70                           &mpcore_scu_ops, s, "mpcore-scu", 0x100);
71     sysbus_init_mmio(sbd, &s->iomem);
72 }
73 
74 static Property arm11_scu_properties[] = {
75     DEFINE_PROP_UINT32("num-cpu", ARM11SCUState, num_cpu, 1),
76     DEFINE_PROP_END_OF_LIST()
77 };
78 
79 static void arm11_scu_class_init(ObjectClass *oc, void *data)
80 {
81     DeviceClass *dc = DEVICE_CLASS(oc);
82 
83     dc->realize = arm11_scu_realize;
84     dc->props = arm11_scu_properties;
85 }
86 
87 static const TypeInfo arm11_scu_type_info = {
88     .name          = TYPE_ARM11_SCU,
89     .parent        = TYPE_SYS_BUS_DEVICE,
90     .instance_size = sizeof(ARM11SCUState),
91     .instance_init = arm11_scu_init,
92     .class_init    = arm11_scu_class_init,
93 };
94 
95 static void arm11_scu_register_types(void)
96 {
97     type_register_static(&arm11_scu_type_info);
98 }
99 
100 type_init(arm11_scu_register_types)
101