xref: /openbmc/qemu/hw/misc/avr_power.c (revision b14df228)
1 /*
2  * AVR Power Reduction Management
3  *
4  * Copyright (c) 2019-2020 Michael Rolnik
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "hw/misc/avr_power.h"
27 #include "qemu/log.h"
28 #include "hw/qdev-properties.h"
29 #include "hw/irq.h"
30 #include "trace.h"
31 
32 static void avr_mask_reset(DeviceState *dev)
33 {
34     AVRMaskState *s = AVR_MASK(dev);
35 
36     s->val = 0x00;
37 
38     for (int i = 0; i < 8; i++) {
39         qemu_set_irq(s->irq[i], 0);
40     }
41 }
42 
43 static uint64_t avr_mask_read(void *opaque, hwaddr offset, unsigned size)
44 {
45     assert(size == 1);
46     assert(offset == 0);
47     AVRMaskState *s = opaque;
48 
49     trace_avr_power_read(s->val);
50 
51     return (uint64_t)s->val;
52 }
53 
54 static void avr_mask_write(void *opaque, hwaddr offset,
55                            uint64_t val64, unsigned size)
56 {
57     assert(size == 1);
58     assert(offset == 0);
59     AVRMaskState *s = opaque;
60     uint8_t val8 = val64;
61 
62     trace_avr_power_write(val8);
63     s->val = val8;
64     for (int i = 0; i < 8; i++) {
65         qemu_set_irq(s->irq[i], (val8 & (1 << i)) != 0);
66     }
67 }
68 
69 static const MemoryRegionOps avr_mask_ops = {
70     .read = avr_mask_read,
71     .write = avr_mask_write,
72     .endianness = DEVICE_NATIVE_ENDIAN,
73     .impl = {
74         .max_access_size = 1,
75     },
76 };
77 
78 static void avr_mask_init(Object *dev)
79 {
80     AVRMaskState *s = AVR_MASK(dev);
81     SysBusDevice *busdev = SYS_BUS_DEVICE(dev);
82 
83     memory_region_init_io(&s->iomem, dev, &avr_mask_ops, s, TYPE_AVR_MASK,
84                           0x01);
85     sysbus_init_mmio(busdev, &s->iomem);
86 
87     for (int i = 0; i < 8; i++) {
88         sysbus_init_irq(busdev, &s->irq[i]);
89     }
90     s->val = 0x00;
91 }
92 
93 static void avr_mask_class_init(ObjectClass *klass, void *data)
94 {
95     DeviceClass *dc = DEVICE_CLASS(klass);
96 
97     dc->reset = avr_mask_reset;
98 }
99 
100 static const TypeInfo avr_mask_info = {
101     .name          = TYPE_AVR_MASK,
102     .parent        = TYPE_SYS_BUS_DEVICE,
103     .instance_size = sizeof(AVRMaskState),
104     .class_init    = avr_mask_class_init,
105     .instance_init = avr_mask_init,
106 };
107 
108 static void avr_mask_register_types(void)
109 {
110     type_register_static(&avr_mask_info);
111 }
112 
113 type_init(avr_mask_register_types)
114