summaryrefslogtreecommitdiff
path: root/hw/lm32_juart.c
blob: 5454aa4e4dd7db1fc18178a3ee3b8b2b56425a4e (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
/*
 *  LatticeMico32 JTAG UART model.
 *
 *  Copyright (c) 2010 Michael Walle <michael@walle.cc>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */

#include "hw.h"
#include "sysbus.h"
#include "trace.h"
#include "qemu-char.h"

#include "lm32_juart.h"

enum {
    LM32_JUART_MIN_SAVE_VERSION = 0,
    LM32_JUART_CURRENT_SAVE_VERSION = 0,
    LM32_JUART_MAX_SAVE_VERSION = 0,
};

enum {
    JTX_FULL = (1<<8),
};

enum {
    JRX_FULL = (1<<8),
};

struct LM32JuartState {
    SysBusDevice busdev;
    CharDriverState *chr;

    uint32_t jtx;
    uint32_t jrx;
};
typedef struct LM32JuartState LM32JuartState;

uint32_t lm32_juart_get_jtx(DeviceState *d)
{
    LM32JuartState *s = container_of(d, LM32JuartState, busdev.qdev);

    trace_lm32_juart_get_jtx(s->jtx);
    return s->jtx;
}

uint32_t lm32_juart_get_jrx(DeviceState *d)
{
    LM32JuartState *s = container_of(d, LM32JuartState, busdev.qdev);

    trace_lm32_juart_get_jrx(s->jrx);
    return s->jrx;
}

void lm32_juart_set_jtx(DeviceState *d, uint32_t jtx)
{
    LM32JuartState *s = container_of(d, LM32JuartState, busdev.qdev);
    unsigned char ch = jtx & 0xff;

    trace_lm32_juart_set_jtx(s->jtx);

    s->jtx = jtx;
    if (s->chr) {
        qemu_chr_fe_write(s->chr, &ch, 1);
    }
}

void lm32_juart_set_jrx(DeviceState *d, uint32_t jtx)
{
    LM32JuartState *s = container_of(d, LM32JuartState, busdev.qdev);

    trace_lm32_juart_set_jrx(s->jrx);
    s->jrx &= ~JRX_FULL;
}

static void juart_rx(void *opaque, const uint8_t *buf, int size)
{
    LM32JuartState *s = opaque;

    s->jrx = *buf | JRX_FULL;
}

static int juart_can_rx(void *opaque)
{
    LM32JuartState *s = opaque;

    return !(s->jrx & JRX_FULL);
}

static void juart_event(void *opaque, int event)
{
}

static void juart_reset(DeviceState *d)
{
    LM32JuartState *s = container_of(d, LM32JuartState, busdev.qdev);

    s->jtx = 0;
    s->jrx = 0;
}

static int lm32_juart_init(SysBusDevice *dev)
{
    LM32JuartState *s = FROM_SYSBUS(typeof(*s), dev);

    s->chr = qdev_init_chardev(&dev->qdev);
    if (s->chr) {
        qemu_chr_add_handlers(s->chr, juart_can_rx, juart_rx, juart_event, s);
    }

    return 0;
}

static const VMStateDescription vmstate_lm32_juart = {
    .name = "lm32-juart",
    .version_id = 1,
    .minimum_version_id = 1,
    .minimum_version_id_old = 1,
    .fields      = (VMStateField[]) {
        VMSTATE_UINT32(jtx, LM32JuartState),
        VMSTATE_UINT32(jrx, LM32JuartState),
        VMSTATE_END_OF_LIST()
    }
};

static SysBusDeviceInfo lm32_juart_info = {
    .init = lm32_juart_init,
    .qdev.name  = "lm32-juart",
    .qdev.size  = sizeof(LM32JuartState),
    .qdev.vmsd  = &vmstate_lm32_juart,
    .qdev.reset = juart_reset,
};

static void lm32_juart_register(void)
{
    sysbus_register_withprop(&lm32_juart_info);
}

device_init(lm32_juart_register)