xref: /openbmc/qemu/hw/misc/a9scu.c (revision 09a274d8)
1 /*
2  * Cortex-A9MPCore Snoop Control Unit (SCU) emulation.
3  *
4  * Copyright (c) 2009 CodeSourcery.
5  * Copyright (c) 2011 Linaro Limited.
6  * Written by Paul Brook, Peter Maydell.
7  *
8  * This code is licensed under the GPL.
9  */
10 
11 #include "qemu/osdep.h"
12 #include "hw/misc/a9scu.h"
13 
14 static uint64_t a9_scu_read(void *opaque, hwaddr offset,
15                             unsigned size)
16 {
17     A9SCUState *s = (A9SCUState *)opaque;
18     switch (offset) {
19     case 0x00: /* Control */
20         return s->control;
21     case 0x04: /* Configuration */
22         return (((1 << s->num_cpu) - 1) << 4) | (s->num_cpu - 1);
23     case 0x08: /* CPU Power Status */
24         return s->status;
25     case 0x09: /* CPU status.  */
26         return s->status >> 8;
27     case 0x0a: /* CPU status.  */
28         return s->status >> 16;
29     case 0x0b: /* CPU status.  */
30         return s->status >> 24;
31     case 0x0c: /* Invalidate All Registers In Secure State */
32         return 0;
33     case 0x40: /* Filtering Start Address Register */
34     case 0x44: /* Filtering End Address Register */
35         /* RAZ/WI, like an implementation with only one AXI master */
36         return 0;
37     case 0x50: /* SCU Access Control Register */
38     case 0x54: /* SCU Non-secure Access Control Register */
39         /* unimplemented, fall through */
40     default:
41         return 0;
42     }
43 }
44 
45 static void a9_scu_write(void *opaque, hwaddr offset,
46                          uint64_t value, unsigned size)
47 {
48     A9SCUState *s = (A9SCUState *)opaque;
49     uint32_t mask;
50     uint32_t shift;
51     switch (size) {
52     case 1:
53         mask = 0xff;
54         break;
55     case 2:
56         mask = 0xffff;
57         break;
58     case 4:
59         mask = 0xffffffff;
60         break;
61     default:
62         fprintf(stderr, "Invalid size %u in write to a9 scu register %x\n",
63                 size, (unsigned)offset);
64         return;
65     }
66 
67     switch (offset) {
68     case 0x00: /* Control */
69         s->control = value & 1;
70         break;
71     case 0x4: /* Configuration: RO */
72         break;
73     case 0x08: case 0x09: case 0x0A: case 0x0B: /* Power Control */
74         shift = (offset - 0x8) * 8;
75         s->status &= ~(mask << shift);
76         s->status |= ((value & mask) << shift);
77         break;
78     case 0x0c: /* Invalidate All Registers In Secure State */
79         /* no-op as we do not implement caches */
80         break;
81     case 0x40: /* Filtering Start Address Register */
82     case 0x44: /* Filtering End Address Register */
83         /* RAZ/WI, like an implementation with only one AXI master */
84         break;
85     case 0x50: /* SCU Access Control Register */
86     case 0x54: /* SCU Non-secure Access Control Register */
87         /* unimplemented, fall through */
88     default:
89         break;
90     }
91 }
92 
93 static const MemoryRegionOps a9_scu_ops = {
94     .read = a9_scu_read,
95     .write = a9_scu_write,
96     .endianness = DEVICE_NATIVE_ENDIAN,
97 };
98 
99 static void a9_scu_reset(DeviceState *dev)
100 {
101     A9SCUState *s = A9_SCU(dev);
102     s->control = 0;
103 }
104 
105 static void a9_scu_init(Object *obj)
106 {
107     A9SCUState *s = A9_SCU(obj);
108     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
109 
110     memory_region_init_io(&s->iomem, obj, &a9_scu_ops, s,
111                           "a9-scu", 0x100);
112     sysbus_init_mmio(sbd, &s->iomem);
113 }
114 
115 static const VMStateDescription vmstate_a9_scu = {
116     .name = "a9-scu",
117     .version_id = 1,
118     .minimum_version_id = 1,
119     .fields = (VMStateField[]) {
120         VMSTATE_UINT32(control, A9SCUState),
121         VMSTATE_UINT32(status, A9SCUState),
122         VMSTATE_END_OF_LIST()
123     }
124 };
125 
126 static Property a9_scu_properties[] = {
127     DEFINE_PROP_UINT32("num-cpu", A9SCUState, num_cpu, 1),
128     DEFINE_PROP_END_OF_LIST(),
129 };
130 
131 static void a9_scu_class_init(ObjectClass *klass, void *data)
132 {
133     DeviceClass *dc = DEVICE_CLASS(klass);
134 
135     dc->props = a9_scu_properties;
136     dc->vmsd = &vmstate_a9_scu;
137     dc->reset = a9_scu_reset;
138 }
139 
140 static const TypeInfo a9_scu_info = {
141     .name          = TYPE_A9_SCU,
142     .parent        = TYPE_SYS_BUS_DEVICE,
143     .instance_size = sizeof(A9SCUState),
144     .instance_init = a9_scu_init,
145     .class_init    = a9_scu_class_init,
146 };
147 
148 static void a9mp_register_types(void)
149 {
150     type_register_static(&a9_scu_info);
151 }
152 
153 type_init(a9mp_register_types)
154