PPC: e500: msync is 440 only, e500 has real sync
[qemu.git] / hw / ds1338.c
1 /*
2 * MAXIM DS1338 I2C RTC+NVRAM
3 *
4 * Copyright (c) 2009 CodeSourcery.
5 * Written by Paul Brook
6 *
7 * This code is licensed under the GNU GPL v2.
8 *
9 * Contributions after 2012-01-13 are licensed under the terms of the
10 * GNU GPL, version 2 or (at your option) any later version.
11 */
12
13 #include "i2c.h"
14
15 typedef struct {
16 I2CSlave i2c;
17 time_t offset;
18 struct tm now;
19 uint8_t nvram[56];
20 int ptr;
21 int addr_byte;
22 } DS1338State;
23
24 static void ds1338_event(I2CSlave *i2c, enum i2c_event event)
25 {
26 DS1338State *s = FROM_I2C_SLAVE(DS1338State, i2c);
27
28 switch (event) {
29 case I2C_START_RECV:
30 qemu_get_timedate(&s->now, s->offset);
31 s->nvram[0] = to_bcd(s->now.tm_sec);
32 s->nvram[1] = to_bcd(s->now.tm_min);
33 if (s->nvram[2] & 0x40) {
34 s->nvram[2] = (to_bcd((s->now.tm_hour % 12)) + 1) | 0x40;
35 if (s->now.tm_hour >= 12) {
36 s->nvram[2] |= 0x20;
37 }
38 } else {
39 s->nvram[2] = to_bcd(s->now.tm_hour);
40 }
41 s->nvram[3] = to_bcd(s->now.tm_wday) + 1;
42 s->nvram[4] = to_bcd(s->now.tm_mday);
43 s->nvram[5] = to_bcd(s->now.tm_mon) + 1;
44 s->nvram[6] = to_bcd(s->now.tm_year - 100);
45 break;
46 case I2C_START_SEND:
47 s->addr_byte = 1;
48 break;
49 default:
50 break;
51 }
52 }
53
54 static int ds1338_recv(I2CSlave *i2c)
55 {
56 DS1338State *s = FROM_I2C_SLAVE(DS1338State, i2c);
57 uint8_t res;
58
59 res = s->nvram[s->ptr];
60 s->ptr = (s->ptr + 1) & 0xff;
61 return res;
62 }
63
64 static int ds1338_send(I2CSlave *i2c, uint8_t data)
65 {
66 DS1338State *s = FROM_I2C_SLAVE(DS1338State, i2c);
67 if (s->addr_byte) {
68 s->ptr = data;
69 s->addr_byte = 0;
70 return 0;
71 }
72 s->nvram[s->ptr - 8] = data;
73 if (data < 8) {
74 qemu_get_timedate(&s->now, s->offset);
75 switch(data) {
76 case 0:
77 /* TODO: Implement CH (stop) bit. */
78 s->now.tm_sec = from_bcd(data & 0x7f);
79 break;
80 case 1:
81 s->now.tm_min = from_bcd(data & 0x7f);
82 break;
83 case 2:
84 if (data & 0x40) {
85 if (data & 0x20) {
86 data = from_bcd(data & 0x4f) + 11;
87 } else {
88 data = from_bcd(data & 0x1f) - 1;
89 }
90 } else {
91 data = from_bcd(data);
92 }
93 s->now.tm_hour = data;
94 break;
95 case 3:
96 s->now.tm_wday = from_bcd(data & 7) - 1;
97 break;
98 case 4:
99 s->now.tm_mday = from_bcd(data & 0x3f);
100 break;
101 case 5:
102 s->now.tm_mon = from_bcd(data & 0x1f) - 1;
103 case 6:
104 s->now.tm_year = from_bcd(data) + 100;
105 break;
106 case 7:
107 /* Control register. Currently ignored. */
108 break;
109 }
110 s->offset = qemu_timedate_diff(&s->now);
111 }
112 s->ptr = (s->ptr + 1) & 0xff;
113 return 0;
114 }
115
116 static int ds1338_init(I2CSlave *i2c)
117 {
118 return 0;
119 }
120
121 static void ds1338_class_init(ObjectClass *klass, void *data)
122 {
123 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
124
125 k->init = ds1338_init;
126 k->event = ds1338_event;
127 k->recv = ds1338_recv;
128 k->send = ds1338_send;
129 }
130
131 static DeviceInfo ds1338_info = {
132 .name = "ds1338",
133 .size = sizeof(DS1338State),
134 .class_init = ds1338_class_init,
135 };
136
137 static void ds1338_register_devices(void)
138 {
139 i2c_register_slave(&ds1338_info);
140 }
141
142 device_init(ds1338_register_devices)