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13#include "qemu/osdep.h"
14#include "qemu-common.h"
15#include "hw/i2c/i2c.h"
16#include "migration/vmstate.h"
17#include "qemu/bcd.h"
18#include "qemu/module.h"
19#include "qom/object.h"
20
21
22
23
24#define NVRAM_SIZE 64
25
26
27#define SECONDS_CH 0x80
28#define HOURS_12 0x40
29#define HOURS_PM 0x20
30#define CTRL_OSF 0x20
31
32#define TYPE_DS1338 "ds1338"
33OBJECT_DECLARE_SIMPLE_TYPE(DS1338State, DS1338)
34
35struct DS1338State {
36 I2CSlave parent_obj;
37
38 int64_t offset;
39 uint8_t wday_offset;
40 uint8_t nvram[NVRAM_SIZE];
41 int32_t ptr;
42 bool addr_byte;
43};
44
45static const VMStateDescription vmstate_ds1338 = {
46 .name = "ds1338",
47 .version_id = 2,
48 .minimum_version_id = 1,
49 .fields = (VMStateField[]) {
50 VMSTATE_I2C_SLAVE(parent_obj, DS1338State),
51 VMSTATE_INT64(offset, DS1338State),
52 VMSTATE_UINT8_V(wday_offset, DS1338State, 2),
53 VMSTATE_UINT8_ARRAY(nvram, DS1338State, NVRAM_SIZE),
54 VMSTATE_INT32(ptr, DS1338State),
55 VMSTATE_BOOL(addr_byte, DS1338State),
56 VMSTATE_END_OF_LIST()
57 }
58};
59
60static void capture_current_time(DS1338State *s)
61{
62
63
64
65 struct tm now;
66 qemu_get_timedate(&now, s->offset);
67 s->nvram[0] = to_bcd(now.tm_sec);
68 s->nvram[1] = to_bcd(now.tm_min);
69 if (s->nvram[2] & HOURS_12) {
70 int tmp = now.tm_hour;
71 if (tmp % 12 == 0) {
72 tmp += 12;
73 }
74 if (tmp <= 12) {
75 s->nvram[2] = HOURS_12 | to_bcd(tmp);
76 } else {
77 s->nvram[2] = HOURS_12 | HOURS_PM | to_bcd(tmp - 12);
78 }
79 } else {
80 s->nvram[2] = to_bcd(now.tm_hour);
81 }
82 s->nvram[3] = (now.tm_wday + s->wday_offset) % 7 + 1;
83 s->nvram[4] = to_bcd(now.tm_mday);
84 s->nvram[5] = to_bcd(now.tm_mon + 1);
85 s->nvram[6] = to_bcd(now.tm_year - 100);
86}
87
88static void inc_regptr(DS1338State *s)
89{
90
91
92
93
94 s->ptr = (s->ptr + 1) & (NVRAM_SIZE - 1);
95 if (!s->ptr) {
96 capture_current_time(s);
97 }
98}
99
100static int ds1338_event(I2CSlave *i2c, enum i2c_event event)
101{
102 DS1338State *s = DS1338(i2c);
103
104 switch (event) {
105 case I2C_START_RECV:
106
107
108
109
110
111 capture_current_time(s);
112 break;
113 case I2C_START_SEND:
114 s->addr_byte = true;
115 break;
116 default:
117 break;
118 }
119
120 return 0;
121}
122
123static uint8_t ds1338_recv(I2CSlave *i2c)
124{
125 DS1338State *s = DS1338(i2c);
126 uint8_t res;
127
128 res = s->nvram[s->ptr];
129 inc_regptr(s);
130 return res;
131}
132
133static int ds1338_send(I2CSlave *i2c, uint8_t data)
134{
135 DS1338State *s = DS1338(i2c);
136
137 if (s->addr_byte) {
138 s->ptr = data & (NVRAM_SIZE - 1);
139 s->addr_byte = false;
140 return 0;
141 }
142 if (s->ptr < 7) {
143
144 struct tm now;
145 qemu_get_timedate(&now, s->offset);
146 switch(s->ptr) {
147 case 0:
148
149 now.tm_sec = from_bcd(data & 0x7f);
150 break;
151 case 1:
152 now.tm_min = from_bcd(data & 0x7f);
153 break;
154 case 2:
155 if (data & HOURS_12) {
156 int tmp = from_bcd(data & (HOURS_PM - 1));
157 if (data & HOURS_PM) {
158 tmp += 12;
159 }
160 if (tmp % 12 == 0) {
161 tmp -= 12;
162 }
163 now.tm_hour = tmp;
164 } else {
165 now.tm_hour = from_bcd(data & (HOURS_12 - 1));
166 }
167 break;
168 case 3:
169 {
170
171
172
173 int user_wday = (data & 7) - 1;
174 s->wday_offset = (user_wday - now.tm_wday + 7) % 7;
175 }
176 break;
177 case 4:
178 now.tm_mday = from_bcd(data & 0x3f);
179 break;
180 case 5:
181 now.tm_mon = from_bcd(data & 0x1f) - 1;
182 break;
183 case 6:
184 now.tm_year = from_bcd(data) + 100;
185 break;
186 }
187 s->offset = qemu_timedate_diff(&now);
188 } else if (s->ptr == 7) {
189
190
191
192 data &= 0xB3;
193
194
195
196 data = (data & ~CTRL_OSF) | (data & s->nvram[s->ptr] & CTRL_OSF);
197
198 s->nvram[s->ptr] = data;
199 } else {
200 s->nvram[s->ptr] = data;
201 }
202 inc_regptr(s);
203 return 0;
204}
205
206static void ds1338_reset(DeviceState *dev)
207{
208 DS1338State *s = DS1338(dev);
209
210
211 s->offset = 0;
212 s->wday_offset = 0;
213 memset(s->nvram, 0, NVRAM_SIZE);
214 s->ptr = 0;
215 s->addr_byte = false;
216}
217
218static void ds1338_class_init(ObjectClass *klass, void *data)
219{
220 DeviceClass *dc = DEVICE_CLASS(klass);
221 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
222
223 k->event = ds1338_event;
224 k->recv = ds1338_recv;
225 k->send = ds1338_send;
226 dc->reset = ds1338_reset;
227 dc->vmsd = &vmstate_ds1338;
228}
229
230static const TypeInfo ds1338_info = {
231 .name = TYPE_DS1338,
232 .parent = TYPE_I2C_SLAVE,
233 .instance_size = sizeof(DS1338State),
234 .class_init = ds1338_class_init,
235};
236
237static void ds1338_register_types(void)
238{
239 type_register_static(&ds1338_info);
240}
241
242type_init(ds1338_register_types)
243