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
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/*
* QEMU model of the Canon DIGIC UART block.
*
* Copyright (C) 2013 Antony Pavlov <antonynpavlov@gmail.com>
*
* This model is based on reverse engineering efforts
* made by CHDK (http://chdk.wikia.com) and
* Magic Lantern (http://www.magiclantern.fm) projects
* contributors.
*
* See "Serial terminal" docs here:
* http://magiclantern.wikia.com/wiki/Register_Map#Misc_Registers
*
* The QEMU model of the Milkymist UART block by Michael Walle
* is used as a template.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
*/
#include "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/sysbus.h"
#include "sysemu/char.h"
#include "qemu/log.h"
#include "hw/char/digic-uart.h"
enum {
ST_RX_RDY = (1 << 0),
ST_TX_RDY = (1 << 1),
};
static uint64_t digic_uart_read(void *opaque, hwaddr addr,
unsigned size)
{
DigicUartState *s = opaque;
uint64_t ret = 0;
addr >>= 2;
switch (addr) {
case R_RX:
s->reg_st &= ~(ST_RX_RDY);
ret = s->reg_rx;
break;
case R_ST:
ret = s->reg_st;
break;
default:
qemu_log_mask(LOG_UNIMP,
"digic-uart: read access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
}
return ret;
}
static void digic_uart_write(void *opaque, hwaddr addr, uint64_t value,
unsigned size)
{
DigicUartState *s = opaque;
unsigned char ch = value;
addr >>= 2;
switch (addr) {
case R_TX:
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
qemu_chr_fe_write_all(&s->chr, &ch, 1);
break;
case R_ST:
/*
* Ignore write to R_ST.
*
* The point is that this register is actively used
* during receiving and transmitting symbols,
* but we don't know the function of most of bits.
*
* Ignoring writes to R_ST is only a simplification
* of the model. It has no perceptible side effects
* for existing guests.
*/
break;
default:
qemu_log_mask(LOG_UNIMP,
"digic-uart: write access to unknown register 0x"
TARGET_FMT_plx, addr << 2);
}
}
static const MemoryRegionOps uart_mmio_ops = {
.read = digic_uart_read,
.write = digic_uart_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static int uart_can_rx(void *opaque)
{
DigicUartState *s = opaque;
return !(s->reg_st & ST_RX_RDY);
}
static void uart_rx(void *opaque, const uint8_t *buf, int size)
{
DigicUartState *s = opaque;
assert(uart_can_rx(opaque));
s->reg_st |= ST_RX_RDY;
s->reg_rx = *buf;
}
static void uart_event(void *opaque, int event)
{
}
static void digic_uart_reset(DeviceState *d)
{
DigicUartState *s = DIGIC_UART(d);
s->reg_rx = 0;
s->reg_st = ST_TX_RDY;
}
static void digic_uart_realize(DeviceState *dev, Error **errp)
{
DigicUartState *s = DIGIC_UART(dev);
qemu_chr_fe_set_handlers(&s->chr, uart_can_rx, uart_rx,
uart_event, s, NULL, true);
}
static void digic_uart_init(Object *obj)
{
DigicUartState *s = DIGIC_UART(obj);
memory_region_init_io(&s->regs_region, OBJECT(s), &uart_mmio_ops, s,
TYPE_DIGIC_UART, 0x18);
sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->regs_region);
}
static const VMStateDescription vmstate_digic_uart = {
.name = "digic-uart",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32(reg_rx, DigicUartState),
VMSTATE_UINT32(reg_st, DigicUartState),
VMSTATE_END_OF_LIST()
}
};
static Property digic_uart_properties[] = {
DEFINE_PROP_CHR("chardev", DigicUartState, chr),
DEFINE_PROP_END_OF_LIST(),
};
static void digic_uart_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = digic_uart_realize;
dc->reset = digic_uart_reset;
dc->vmsd = &vmstate_digic_uart;
dc->props = digic_uart_properties;
}
static const TypeInfo digic_uart_info = {
.name = TYPE_DIGIC_UART,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(DigicUartState),
.instance_init = digic_uart_init,
.class_init = digic_uart_class_init,
};
static void digic_uart_register_types(void)
{
type_register_static(&digic_uart_info);
}
type_init(digic_uart_register_types)
|
