xref: /qemu/hw/misc/a9scu.c (revision 9eb39db520cea30620b24098b6d731f78cc819a0) !
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 "hw/sysbus.h"
12 
13 /* A9MP private memory region.  */
14 
15 typedef struct A9SCUState {
16     /*< private >*/
17     SysBusDevice parent_obj;
18     /*< public >*/
19 
20     MemoryRegion iomem;
21     uint32_t control;
22     uint32_t status;
23     uint32_t num_cpu;
24 } A9SCUState;
25 
26 #define TYPE_A9_SCU "a9-scu"
27 #define A9_SCU(obj) OBJECT_CHECK(A9SCUState, (obj), TYPE_A9_SCU)
28 
29 static uint64_t a9_scu_read(void *opaque, hwaddr offset,
30                             unsigned size)
31 {
32     A9SCUState *s = (A9SCUState *)opaque;
33     switch (offset) {
34     case 0x00: /* Control */
35         return s->control;
36     case 0x04: /* Configuration */
37         return (((1 << s->num_cpu) - 1) << 4) | (s->num_cpu - 1);
38     case 0x08: /* CPU Power Status */
39         return s->status;
40     case 0x09: /* CPU status.  */
41         return s->status >> 8;
42     case 0x0a: /* CPU status.  */
43         return s->status >> 16;
44     case 0x0b: /* CPU status.  */
45         return s->status >> 24;
46     case 0x0c: /* Invalidate All Registers In Secure State */
47         return 0;
48     case 0x40: /* Filtering Start Address Register */
49     case 0x44: /* Filtering End Address Register */
50         /* RAZ/WI, like an implementation with only one AXI master */
51         return 0;
52     case 0x50: /* SCU Access Control Register */
53     case 0x54: /* SCU Non-secure Access Control Register */
54         /* unimplemented, fall through */
55     default:
56         return 0;
57     }
58 }
59 
60 static void a9_scu_write(void *opaque, hwaddr offset,
61                          uint64_t value, unsigned size)
62 {
63     A9SCUState *s = (A9SCUState *)opaque;
64     uint32_t mask;
65     uint32_t shift;
66     switch (size) {
67     case 1:
68         mask = 0xff;
69         break;
70     case 2:
71         mask = 0xffff;
72         break;
73     case 4:
74         mask = 0xffffffff;
75         break;
76     default:
77         fprintf(stderr, "Invalid size %u in write to a9 scu register %x\n",
78                 size, (unsigned)offset);
79         return;
80     }
81 
82     switch (offset) {
83     case 0x00: /* Control */
84         s->control = value & 1;
85         break;
86     case 0x4: /* Configuration: RO */
87         break;
88     case 0x08: case 0x09: case 0x0A: case 0x0B: /* Power Control */
89         shift = (offset - 0x8) * 8;
90         s->status &= ~(mask << shift);
91         s->status |= ((value & mask) << shift);
92         break;
93     case 0x0c: /* Invalidate All Registers In Secure State */
94         /* no-op as we do not implement caches */
95         break;
96     case 0x40: /* Filtering Start Address Register */
97     case 0x44: /* Filtering End Address Register */
98         /* RAZ/WI, like an implementation with only one AXI master */
99         break;
100     case 0x50: /* SCU Access Control Register */
101     case 0x54: /* SCU Non-secure Access Control Register */
102         /* unimplemented, fall through */
103     default:
104         break;
105     }
106 }
107 
108 static const MemoryRegionOps a9_scu_ops = {
109     .read = a9_scu_read,
110     .write = a9_scu_write,
111     .endianness = DEVICE_NATIVE_ENDIAN,
112 };
113 
114 static void a9_scu_reset(DeviceState *dev)
115 {
116     A9SCUState *s = A9_SCU(dev);
117     s->control = 0;
118 }
119 
120 static void a9_scu_init(Object *obj)
121 {
122     A9SCUState *s = A9_SCU(obj);
123     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
124 
125     memory_region_init_io(&s->iomem, obj, &a9_scu_ops, s,
126                           "a9-scu", 0x100);
127     sysbus_init_mmio(sbd, &s->iomem);
128 }
129 
130 static const VMStateDescription vmstate_a9_scu = {
131     .name = "a9-scu",
132     .version_id = 1,
133     .minimum_version_id = 1,
134     .fields = (VMStateField[]) {
135         VMSTATE_UINT32(control, A9SCUState),
136         VMSTATE_UINT32(status, A9SCUState),
137         VMSTATE_END_OF_LIST()
138     }
139 };
140 
141 static Property a9_scu_properties[] = {
142     DEFINE_PROP_UINT32("num-cpu", A9SCUState, num_cpu, 1),
143     DEFINE_PROP_END_OF_LIST(),
144 };
145 
146 static void a9_scu_class_init(ObjectClass *klass, void *data)
147 {
148     DeviceClass *dc = DEVICE_CLASS(klass);
149 
150     dc->props = a9_scu_properties;
151     dc->vmsd = &vmstate_a9_scu;
152     dc->reset = a9_scu_reset;
153 }
154 
155 static const TypeInfo a9_scu_info = {
156     .name          = TYPE_A9_SCU,
157     .parent        = TYPE_SYS_BUS_DEVICE,
158     .instance_size = sizeof(A9SCUState),
159     .instance_init = a9_scu_init,
160     .class_init    = a9_scu_class_init,
161 };
162 
163 static void a9mp_register_types(void)
164 {
165     type_register_static(&a9_scu_info);
166 }
167 
168 type_init(a9mp_register_types)
169