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
|
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2025 Aidan MacDonald
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "rtc.h"
#include "timefuncs.h"
#include "stm32h7/rtc.h"
#include "stm32h7/rcc.h"
#include "stm32h7/pwr.h"
void rtc_init(void)
{
st_writef(RCC_APB4ENR, RTCAPBEN(1));
/* Initialize RTC if needed */
if (!st_readf(RTC_ISR, INITS))
{
struct tm tm = {
.tm_hour = 0,
.tm_min = 0,
.tm_sec = 0,
.tm_year = 101,
.tm_mon = 0,
.tm_mday = 1,
.tm_wday = 1,
.tm_isdst = 0,
};
rtc_write_datetime(&tm);
}
}
int rtc_read_datetime(struct tm *tm)
{
/*
* Wait for RSF bit to indicate time/date registers are valid.
* But if the calendar is not initialized, then don't wait as
* they will never be valid.
*/
bool valid = false;
while (!valid)
{
uint32_t isr = REG_RTC_ISR;
if (!st_vreadf(isr, RTC_ISR, INITS))
break;
if (st_vreadf(isr, RTC_ISR, RSF))
valid = true;
}
if (valid)
{
uint32_t tr = REG_RTC_TR;
uint32_t dr = REG_RTC_DR;
tm->tm_sec = st_vreadf(tr, RTC_TR, ST)*10 + st_vreadf(tr, RTC_TR, SU);
tm->tm_min = st_vreadf(tr, RTC_TR, MNT)*10 + st_vreadf(tr, RTC_TR, MNU);
tm->tm_hour = st_vreadf(tr, RTC_TR, HT)*10 + st_vreadf(tr, RTC_TR, HU);
tm->tm_mday = st_vreadf(dr, RTC_DR, DT)*10 + st_vreadf(dr, RTC_DR, DU);
tm->tm_mon = st_vreadf(dr, RTC_DR, MT)*10 + st_vreadf(dr, RTC_DR, MU) - 1;
tm->tm_year = 100 + st_vreadf(dr, RTC_DR, YT)*10 + st_vreadf(dr, RTC_DR, YU);
tm->tm_isdst = st_readf(RTC_CR, BKP);
}
else
{
tm->tm_sec = 0;
tm->tm_min = 0;
tm->tm_hour = 0;
tm->tm_mday = 1;
tm->tm_mon = 0;
tm->tm_year = 101;
tm->tm_isdst = 0;
}
set_day_of_week(tm);
set_day_of_year(tm);
return 1;
}
int rtc_write_datetime(const struct tm *tm)
{
/* Allow RTC write protection */
st_writef(PWR_CR1, DBP(1));
/* Unlock registers */
st_writef(RTC_WPR, KEY_V(KEY1));
st_writef(RTC_WPR, KEY_V(KEY2));
/* Enter initialization mode */
st_writef(RTC_ISR, INIT(1));
while (!st_readf(RTC_ISR, INITF));
/* Program calendar and dividers */
st_writef(RTC_PRER, PREDIV_A(127), PREDIV_S(255));
st_writef(RTC_TR,
PM(0),
HT(tm->tm_hour / 10),
HU(tm->tm_hour % 10),
MNT(tm->tm_min / 10),
MNU(tm->tm_min % 10),
ST(tm->tm_sec / 10),
SU(tm->tm_sec % 10));
st_writef(RTC_DR,
WDU(tm->tm_wday == 0 ? 7 : tm->tm_wday),
YT((tm->tm_year / 10) % 10),
YU(tm->tm_year % 10),
MT((tm->tm_mon + 1) / 10),
MU((tm->tm_mon + 1) % 10),
DT(tm->tm_mday / 10),
DU(tm->tm_mday % 10));
st_writef(RTC_CR,
FMT(0),
BKP(!!tm->tm_isdst));
/* Exit initialization */
st_writef(RTC_ISR, INIT(0));
/* Lock registers */
st_writef(RTC_WPR, KEY(0));
st_writef(PWR_CR1, DBP(0));
return 1;
}
#ifdef HAVE_RTC_ALARM
/* TODO */
void rtc_set_alarm(int h, int m)
{
(void)h;
(void)m;
}
void rtc_get_alarm(int *h, int *m)
{
*h = 0;
*m = 0;
}
void rtc_enable_alarm(bool enable)
{
(void)enable;
}
bool rtc_check_alarm_started(bool release_alarm)
{
(void)release_alarm;
return false;
}
bool rtc_check_alarm_flag(void)
{
return false;
}
#endif
|
