aboutsummaryrefslogtreecommitdiff
path: root/hw/rtc/aspeed_rtc.c
blob: 3ca1183558b7714dc9152956e7cfcc197a67eff6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
/*
 * ASPEED Real Time Clock
 * Joel Stanley <joel@jms.id.au>
 *
 * Copyright 2019 IBM Corp
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "qemu/osdep.h"
#include "qemu-common.h"
#include "hw/rtc/aspeed_rtc.h"
#include "migration/vmstate.h"
#include "qemu/log.h"
#include "qemu/timer.h"

#include "trace.h"

#define COUNTER1        (0x00 / 4)
#define COUNTER2        (0x04 / 4)
#define ALARM           (0x08 / 4)
#define CONTROL         (0x10 / 4)
#define ALARM_STATUS    (0x14 / 4)

#define RTC_UNLOCKED    BIT(1)
#define RTC_ENABLED     BIT(0)

static void aspeed_rtc_calc_offset(AspeedRtcState *rtc)
{
    struct tm tm;
    uint32_t year, cent;
    uint32_t reg1 = rtc->reg[COUNTER1];
    uint32_t reg2 = rtc->reg[COUNTER2];

    tm.tm_mday = (reg1 >> 24) & 0x1f;
    tm.tm_hour = (reg1 >> 16) & 0x1f;
    tm.tm_min = (reg1 >> 8) & 0x3f;
    tm.tm_sec = (reg1 >> 0) & 0x3f;

    cent = (reg2 >> 16) & 0x1f;
    year = (reg2 >> 8) & 0x7f;
    tm.tm_mon = ((reg2 >>  0) & 0x0f) - 1;
    tm.tm_year = year + (cent * 100) - 1900;

    rtc->offset = qemu_timedate_diff(&tm);
}

static uint32_t aspeed_rtc_get_counter(AspeedRtcState *rtc, int r)
{
    uint32_t year, cent;
    struct tm now;

    qemu_get_timedate(&now, rtc->offset);

    switch (r) {
    case COUNTER1:
        return (now.tm_mday << 24) | (now.tm_hour << 16) |
            (now.tm_min << 8) | now.tm_sec;
    case COUNTER2:
        cent = (now.tm_year + 1900) / 100;
        year = now.tm_year % 100;
        return ((cent & 0x1f) << 16) | ((year & 0x7f) << 8) |
            ((now.tm_mon + 1) & 0xf);
    default:
        g_assert_not_reached();
    }
}

static uint64_t aspeed_rtc_read(void *opaque, hwaddr addr,
                                unsigned size)
{
    AspeedRtcState *rtc = opaque;
    uint64_t val;
    uint32_t r = addr >> 2;

    switch (r) {
    case COUNTER1:
    case COUNTER2:
        if (rtc->reg[CONTROL] & RTC_ENABLED) {
            rtc->reg[r] = aspeed_rtc_get_counter(rtc, r);
        }
        /* fall through */
    case CONTROL:
        val = rtc->reg[r];
        break;
    case ALARM:
    case ALARM_STATUS:
    default:
        qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr);
        return 0;
    }

    trace_aspeed_rtc_read(addr, val);

    return val;
}

static void aspeed_rtc_write(void *opaque, hwaddr addr,
                             uint64_t val, unsigned size)
{
    AspeedRtcState *rtc = opaque;
    uint32_t r = addr >> 2;

    switch (r) {
    case COUNTER1:
    case COUNTER2:
        if (!(rtc->reg[CONTROL] & RTC_UNLOCKED)) {
            break;
        }
        /* fall through */
    case CONTROL:
        rtc->reg[r] = val;
        aspeed_rtc_calc_offset(rtc);
        break;
    case ALARM:
    case ALARM_STATUS:
    default:
        qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr);
        break;
    }
    trace_aspeed_rtc_write(addr, val);
}

static void aspeed_rtc_reset(DeviceState *d)
{
    AspeedRtcState *rtc = ASPEED_RTC(d);

    rtc->offset = 0;
    memset(rtc->reg, 0, sizeof(rtc->reg));
}

static const MemoryRegionOps aspeed_rtc_ops = {
    .read = aspeed_rtc_read,
    .write = aspeed_rtc_write,
    .endianness = DEVICE_NATIVE_ENDIAN,
};

static const VMStateDescription vmstate_aspeed_rtc = {
    .name = TYPE_ASPEED_RTC,
    .version_id = 1,
    .fields = (VMStateField[]) {
        VMSTATE_UINT32_ARRAY(reg, AspeedRtcState, 0x18),
        VMSTATE_INT32(offset, AspeedRtcState),
        VMSTATE_INT32(offset, AspeedRtcState),
        VMSTATE_END_OF_LIST()
    }
};

static void aspeed_rtc_realize(DeviceState *dev, Error **errp)
{
    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
    AspeedRtcState *s = ASPEED_RTC(dev);

    sysbus_init_irq(sbd, &s->irq);

    memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_rtc_ops, s,
                          "aspeed-rtc", 0x18ULL);
    sysbus_init_mmio(sbd, &s->iomem);
}

static void aspeed_rtc_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);

    dc->realize = aspeed_rtc_realize;
    dc->vmsd = &vmstate_aspeed_rtc;
    dc->reset = aspeed_rtc_reset;
}

static const TypeInfo aspeed_rtc_info = {
    .name          = TYPE_ASPEED_RTC,
    .parent        = TYPE_SYS_BUS_DEVICE,
    .instance_size = sizeof(AspeedRtcState),
    .class_init    = aspeed_rtc_class_init,
};

static void aspeed_rtc_register_types(void)
{
    type_register_static(&aspeed_rtc_info);
}

type_init(aspeed_rtc_register_types)