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 #include "hw/qdev-properties.h"
14 #include "migration/vmstate.h"
15 #include "qapi/error.h"
16 #include "qemu/log.h"
17 #include "qemu/module.h"
18
19 #define A9_SCU_CPU_MAX 4
20
a9_scu_read(void * opaque,hwaddr offset,unsigned size)21 static uint64_t a9_scu_read(void *opaque, hwaddr offset,
22 unsigned size)
23 {
24 A9SCUState *s = (A9SCUState *)opaque;
25 switch (offset) {
26 case 0x00: /* Control */
27 return s->control;
28 case 0x04: /* Configuration */
29 return (((1 << s->num_cpu) - 1) << 4) | (s->num_cpu - 1);
30 case 0x08: /* CPU Power Status */
31 return s->status;
32 case 0x0c: /* Invalidate All Registers In Secure State */
33 return 0;
34 case 0x40: /* Filtering Start Address Register */
35 case 0x44: /* Filtering End Address Register */
36 /* RAZ/WI, like an implementation with only one AXI master */
37 return 0;
38 case 0x50: /* SCU Access Control Register */
39 case 0x54: /* SCU Non-secure Access Control Register */
40 /* unimplemented, fall through */
41 default:
42 qemu_log_mask(LOG_UNIMP, "%s: Unsupported offset 0x%"HWADDR_PRIx"\n",
43 __func__, offset);
44 return 0;
45 }
46 }
47
a9_scu_write(void * opaque,hwaddr offset,uint64_t value,unsigned size)48 static void a9_scu_write(void *opaque, hwaddr offset,
49 uint64_t value, unsigned size)
50 {
51 A9SCUState *s = (A9SCUState *)opaque;
52
53 switch (offset) {
54 case 0x00: /* Control */
55 s->control = value & 1;
56 break;
57 case 0x4: /* Configuration: RO */
58 break;
59 case 0x08: case 0x09: case 0x0A: case 0x0B: /* Power Control */
60 s->status = value;
61 break;
62 case 0x0c: /* Invalidate All Registers In Secure State */
63 /* no-op as we do not implement caches */
64 break;
65 case 0x40: /* Filtering Start Address Register */
66 case 0x44: /* Filtering End Address Register */
67 /* RAZ/WI, like an implementation with only one AXI master */
68 break;
69 case 0x50: /* SCU Access Control Register */
70 case 0x54: /* SCU Non-secure Access Control Register */
71 /* unimplemented, fall through */
72 default:
73 qemu_log_mask(LOG_UNIMP, "%s: Unsupported offset 0x%"HWADDR_PRIx
74 " value 0x%"PRIx64"\n",
75 __func__, offset, value);
76 break;
77 }
78 }
79
80 static const MemoryRegionOps a9_scu_ops = {
81 .read = a9_scu_read,
82 .write = a9_scu_write,
83 .impl = {
84 .min_access_size = 4,
85 .max_access_size = 4,
86 },
87 .valid = {
88 .min_access_size = 1,
89 .max_access_size = 4,
90 },
91 .endianness = DEVICE_NATIVE_ENDIAN,
92 };
93
a9_scu_reset(DeviceState * dev)94 static void a9_scu_reset(DeviceState *dev)
95 {
96 A9SCUState *s = A9_SCU(dev);
97 s->control = 0;
98 }
99
a9_scu_realize(DeviceState * dev,Error ** errp)100 static void a9_scu_realize(DeviceState *dev, Error **errp)
101 {
102 A9SCUState *s = A9_SCU(dev);
103 SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
104
105 if (!s->num_cpu || s->num_cpu > A9_SCU_CPU_MAX) {
106 error_setg(errp, "Illegal CPU count: %u", s->num_cpu);
107 return;
108 }
109
110 memory_region_init_io(&s->iomem, OBJECT(s), &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 = (const 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
a9_scu_class_init(ObjectClass * klass,void * data)131 static void a9_scu_class_init(ObjectClass *klass, void *data)
132 {
133 DeviceClass *dc = DEVICE_CLASS(klass);
134
135 device_class_set_props(dc, a9_scu_properties);
136 dc->vmsd = &vmstate_a9_scu;
137 dc->reset = a9_scu_reset;
138 dc->realize = a9_scu_realize;
139 }
140
141 static const TypeInfo a9_scu_info = {
142 .name = TYPE_A9_SCU,
143 .parent = TYPE_SYS_BUS_DEVICE,
144 .instance_size = sizeof(A9SCUState),
145 .class_init = a9_scu_class_init,
146 };
147
a9mp_register_types(void)148 static void a9mp_register_types(void)
149 {
150 type_register_static(&a9_scu_info);
151 }
152
153 type_init(a9mp_register_types)
154