1 // Copyright 2020 Espressif Systems (Shanghai) PTE LTD
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 #include <stdint.h>
15 #include <time.h>
16 #include <sys/time.h>
17 #include <sys/lock.h>
18
19 #include "esp_attr.h"
20 #include "esp_system.h"
21
22 #include "soc/rtc.h"
23 #include "esp_rom_sys.h"
24
25 #include "esp_private/system_internal.h"
26
27 #include "esp_time_impl.h"
28
29 #include "sdkconfig.h"
30
31 #if CONFIG_IDF_TARGET_ESP32
32 #include "esp32/rom/rtc.h"
33 #include "esp32/clk.h"
34 #include "esp32/rtc.h"
35 #elif CONFIG_IDF_TARGET_ESP32S2
36 #include "esp32s2/rom/rtc.h"
37 #include "esp32s2/clk.h"
38 #include "esp32s2/rtc.h"
39 #elif CONFIG_IDF_TARGET_ESP32S3
40 #include "esp32s3/rom/rtc.h"
41 #include "esp32s3/clk.h"
42 #include "esp32s3/rtc.h"
43 #elif CONFIG_IDF_TARGET_ESP32C3
44 #include "esp32c3/rom/rtc.h"
45 #include "esp32c3/clk.h"
46 #include "esp32c3/rtc.h"
47 #endif
48
49
50
51 // Offset between FRC timer and the RTC.
52 // Initialized after reset or light sleep.
53 #if defined(CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER) && defined(CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER)
54 uint64_t s_microseconds_offset;
55 #endif
56
57 #ifndef CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
58 static uint64_t s_boot_time; // when RTC is used to persist time, two RTC_STORE registers are used to store boot time instead
59 #endif
60
61 static _lock_t s_boot_time_lock;
62
63 static _lock_t s_esp_rtc_time_lock;
64 static RTC_DATA_ATTR uint64_t s_esp_rtc_time_us = 0, s_rtc_last_ticks = 0;
65
66 #if defined( CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER ) || defined( CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER )
esp_time_impl_get_time_since_boot(void)67 uint64_t esp_time_impl_get_time_since_boot(void)
68 {
69 uint64_t microseconds = 0;
70
71 #ifdef CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER
72 #ifdef CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
73 microseconds = s_microseconds_offset + esp_system_get_time();
74 #else
75 microseconds = esp_system_get_time();
76 #endif // CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
77 #elif defined(CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER)
78 microseconds = esp_rtc_get_time_us();
79 #endif // CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER
80 return microseconds;
81 }
82
esp_time_impl_get_time(void)83 uint64_t esp_time_impl_get_time(void)
84 {
85 uint64_t microseconds = 0;
86 #if defined( CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER )
87 microseconds = esp_system_get_time();
88 #elif defined( CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER )
89 microseconds = esp_rtc_get_time_us();
90 #endif // CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER
91 return microseconds;
92 }
93
94 #endif // defined( CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER ) || defined( CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER )
95
96
esp_time_impl_set_boot_time(uint64_t time_us)97 void esp_time_impl_set_boot_time(uint64_t time_us)
98 {
99 _lock_acquire(&s_boot_time_lock);
100 #ifdef CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
101 REG_WRITE(RTC_BOOT_TIME_LOW_REG, (uint32_t) (time_us & 0xffffffff));
102 REG_WRITE(RTC_BOOT_TIME_HIGH_REG, (uint32_t) (time_us >> 32));
103 #else
104 s_boot_time = time_us;
105 #endif
106 _lock_release(&s_boot_time_lock);
107 }
108
esp_clk_rtc_time(void)109 uint64_t esp_clk_rtc_time(void)
110 {
111 #ifdef CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
112 return esp_rtc_get_time_us();
113 #else
114 return 0;
115 #endif
116 }
117
esp_time_impl_get_boot_time(void)118 uint64_t esp_time_impl_get_boot_time(void)
119 {
120 uint64_t result;
121 _lock_acquire(&s_boot_time_lock);
122 #ifdef CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
123 result = ((uint64_t) REG_READ(RTC_BOOT_TIME_LOW_REG)) + (((uint64_t) REG_READ(RTC_BOOT_TIME_HIGH_REG)) << 32);
124 #else
125 result = s_boot_time;
126 #endif
127 _lock_release(&s_boot_time_lock);
128 return result;
129 }
130
esp_clk_slowclk_cal_get(void)131 uint32_t esp_clk_slowclk_cal_get(void)
132 {
133 return REG_READ(RTC_SLOW_CLK_CAL_REG);
134 }
135
esp_rtc_get_time_us(void)136 uint64_t esp_rtc_get_time_us(void)
137 {
138 _lock_acquire(&s_esp_rtc_time_lock);
139 const uint32_t cal = esp_clk_slowclk_cal_get();
140 const uint64_t rtc_this_ticks = rtc_time_get();
141 const uint64_t ticks = rtc_this_ticks - s_rtc_last_ticks;
142 /* RTC counter result is up to 2^48, calibration factor is up to 2^24,
143 * for a 32kHz clock. We need to calculate (assuming no overflow):
144 * (ticks * cal) >> RTC_CLK_CAL_FRACT
145 *
146 * An overflow in the (ticks * cal) multiplication would cause time to
147 * wrap around after approximately 13 days, which is probably not enough
148 * for some applications.
149 * Therefore multiplication is split into two terms, for the lower 32-bit
150 * and the upper 16-bit parts of "ticks", i.e.:
151 * ((ticks_low + 2^32 * ticks_high) * cal) >> RTC_CLK_CAL_FRACT
152 */
153 const uint64_t ticks_low = ticks & UINT32_MAX;
154 const uint64_t ticks_high = ticks >> 32;
155 const uint64_t delta_time_us = ((ticks_low * cal) >> RTC_CLK_CAL_FRACT) +
156 ((ticks_high * cal) << (32 - RTC_CLK_CAL_FRACT));
157 s_esp_rtc_time_us += delta_time_us;
158 s_rtc_last_ticks = rtc_this_ticks;
159 _lock_release(&s_esp_rtc_time_lock);
160 return s_esp_rtc_time_us;
161 }
162
esp_clk_slowclk_cal_set(uint32_t new_cal)163 void esp_clk_slowclk_cal_set(uint32_t new_cal)
164 {
165 #if defined(CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER)
166 /* To force monotonic time values even when clock calibration value changes,
167 * we adjust esp_rtc_time
168 */
169 esp_rtc_get_time_us();
170 #endif // CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
171 REG_WRITE(RTC_SLOW_CLK_CAL_REG, new_cal);
172 }
173
esp_set_time_from_rtc(void)174 void esp_set_time_from_rtc(void)
175 {
176 #if defined( CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER ) && defined( CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER )
177 // initialize time from RTC clock
178 s_microseconds_offset = esp_rtc_get_time_us() - esp_system_get_time();
179 #endif // CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER && CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
180 }
181
esp_sync_counters_rtc_and_frc(void)182 void esp_sync_counters_rtc_and_frc(void)
183 {
184 #if defined( CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER ) && defined( CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER )
185 struct timeval tv;
186 gettimeofday(&tv, NULL);
187 settimeofday(&tv, NULL);
188 int64_t s_microseconds_offset_cur = esp_rtc_get_time_us() - esp_system_get_time();
189 esp_time_impl_set_boot_time(esp_time_impl_get_boot_time() + ((int64_t)s_microseconds_offset - s_microseconds_offset_cur));
190 #endif
191 }
192
esp_time_impl_init(void)193 void esp_time_impl_init(void)
194 {
195 esp_set_time_from_rtc();
196 }
197
