Merge branch 'bugfix/keep_esp_rtc_time_correct' into 'master'

newlib: Keep esp rtc time correct

See merge request espressif/esp-idf!11932
This commit is contained in:
Jiang Jiang Jian
2021-01-27 15:22:43 +08:00
2 changed files with 14 additions and 13 deletions

View File

@ -575,6 +575,7 @@ esp_err_t esp_light_sleep_start(void)
s_config.rtc_clk_cal_period = (time_per_us << RTC_CLK_CAL_FRACT) / rtc_clk_slow_freq_get_hz();
#elif defined(CONFIG_ESP32S2_RTC_CLK_SRC_INT_RC)
s_config.rtc_clk_cal_period = rtc_clk_cal_cycling(RTC_CAL_RTC_MUX, RTC_CLK_SRC_CAL_CYCLES);
esp_clk_slowclk_cal_set(s_config.rtc_clk_cal_period);
#else
s_config.rtc_clk_cal_period = rtc_clk_cal(RTC_CAL_RTC_MUX, RTC_CLK_SRC_CAL_CYCLES);
#endif

View File

@ -59,6 +59,9 @@ static uint64_t s_boot_time; // when RTC is used to persist time, two RTC_STORE
static _lock_t s_boot_time_lock;
static _lock_t s_esp_rtc_time_lock;
static uint64_t s_esp_rtc_time_us, s_rtc_last_ticks;
#if defined( CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER ) || defined( CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER )
uint64_t esp_time_impl_get_time_since_boot(void)
{
@ -131,8 +134,10 @@ uint32_t esp_clk_slowclk_cal_get(void)
uint64_t esp_rtc_get_time_us(void)
{
const uint64_t ticks = rtc_time_get();
_lock_acquire(&s_esp_rtc_time_lock);
const uint32_t cal = esp_clk_slowclk_cal_get();
const uint64_t rtc_this_ticks = rtc_time_get();
const uint64_t ticks = rtc_this_ticks - s_rtc_last_ticks;
/* RTC counter result is up to 2^48, calibration factor is up to 2^24,
* for a 32kHz clock. We need to calculate (assuming no overflow):
* (ticks * cal) >> RTC_CLK_CAL_FRACT
@ -146,26 +151,21 @@ uint64_t esp_rtc_get_time_us(void)
*/
const uint64_t ticks_low = ticks & UINT32_MAX;
const uint64_t ticks_high = ticks >> 32;
return ((ticks_low * cal) >> RTC_CLK_CAL_FRACT) +
const uint64_t delta_time_us = ((ticks_low * cal) >> RTC_CLK_CAL_FRACT) +
((ticks_high * cal) << (32 - RTC_CLK_CAL_FRACT));
s_esp_rtc_time_us += delta_time_us;
s_rtc_last_ticks = rtc_this_ticks;
_lock_release(&s_esp_rtc_time_lock);
return s_esp_rtc_time_us;
}
void esp_clk_slowclk_cal_set(uint32_t new_cal)
{
#if defined(CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER)
/* To force monotonic time values even when clock calibration value changes,
* we adjust boot time, given current time and the new calibration value:
* T = boot_time_old + cur_cal * ticks / 2^19
* T = boot_time_adj + new_cal * ticks / 2^19
* which results in:
* boot_time_adj = boot_time_old + ticks * (cur_cal - new_cal) / 2^19
* we adjust esp_rtc_time
*/
const int64_t ticks = (int64_t) rtc_time_get();
const uint32_t cur_cal = REG_READ(RTC_SLOW_CLK_CAL_REG);
int32_t cal_diff = (int32_t) (cur_cal - new_cal);
int64_t boot_time_diff = ticks * cal_diff / (1LL << RTC_CLK_CAL_FRACT);
uint64_t boot_time_adj = esp_time_impl_get_boot_time() + boot_time_diff;
esp_time_impl_set_boot_time(boot_time_adj);
esp_rtc_get_time_us();
#endif // CONFIG_ESP_TIME_FUNCS_USE_RTC_TIMER
REG_WRITE(RTC_SLOW_CLK_CAL_REG, new_cal);
}