py/mphal.h: Introduce mp_hal_time_ns and implement on various ports.

This should return a 64-bit value being the number of nanoseconds since
1970/1/1.
Signed-off-by: Damien George <damien@micropython.org>

ports/esp32/mphalport.c

@@ -28,6 +28,7 @@
 
 #include <stdio.h>
 #include <string.h>
+#include <sys/time.h>
 
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
@@ -195,6 +196,12 @@ void mp_hal_delay_us(uint32_t us) {
     }
 }
 
+uint64_t mp_hal_time_ns(void) {
+    struct timeval tv;
+    gettimeofday(&tv, NULL);
+    return (uint64_t)tv.tv_sec * 1000000000ULL + (uint64_t)tv.tv_usec * 1000ULL;
+}
+
 // Wake up the main task if it is sleeping
 void mp_hal_wake_main_task_from_isr(void) {
     BaseType_t xHigherPriorityTaskWoken = pdFALSE;

ports/esp8266/esp_mphal.c

@@ -138,6 +138,10 @@ void MP_FASTCODE(mp_hal_delay_ms)(uint32_t delay) {
     mp_hal_delay_us(delay * 1000);
 }
 
+uint64_t mp_hal_time_ns(void) {
+    return pyb_rtc_get_us_since_2000() * 1000ULL;
+}
+
 void ets_event_poll(void) {
     ets_loop_iter();
     mp_handle_pending(true);

ports/stm32/rtc.c

@@ -27,6 +27,7 @@
 #include <stdio.h>
 
 #include "py/runtime.h"
+#include "lib/timeutils/timeutils.h"
 #include "extint.h"
 #include "rtc.h"
 #include "irq.h"
@@ -442,6 +443,23 @@ STATIC void RTC_CalendarConfig(void) {
     }
 }
 
+uint64_t mp_hal_time_ns(void) {
+    uint64_t ns = 0;
+    #if MICROPY_HW_ENABLE_RTC
+    // Get current according to the RTC.
+    rtc_init_finalise();
+    RTC_TimeTypeDef time;
+    RTC_DateTypeDef date;
+    HAL_RTC_GetTime(&RTCHandle, &time, RTC_FORMAT_BIN);
+    HAL_RTC_GetDate(&RTCHandle, &date, RTC_FORMAT_BIN);
+    ns = timeutils_nanoseconds_since_1970(
+        2000 + date.Year, date.Month, date.Date, time.Hours, time.Minutes, time.Seconds);
+    uint32_t usec = ((RTC_SYNCH_PREDIV - time.SubSeconds) * (1000000 / 64)) / ((RTC_SYNCH_PREDIV + 1) / 64);
+    ns += usec * 1000;
+    #endif
+    return ns;
+}
+
 /******************************************************************************/
 // MicroPython bindings
 

ports/unix/unix_mphal.c

@@ -214,3 +214,8 @@ mp_uint_t mp_hal_ticks_us(void) {
     return tv.tv_sec * 1000000 + tv.tv_usec;
     #endif
 }
+
+uint64_t mp_hal_time_ns(void) {
+    time_t now = time(NULL);
+    return (uint64_t)now * 1000000000ULL;
+}

ports/zephyr/mphalport.h

@@ -24,6 +24,11 @@ static inline void mp_hal_delay_ms(mp_uint_t delay) {
     k_msleep(delay);
 }
 
+static inline uint64_t mp_hal_time_ns(void) {
+    // Not currently implemented.
+    return 0;
+}
+
 #define mp_hal_delay_us_fast(us)   (mp_hal_delay_us(us))
 #define mp_hal_pin_od_low(p)       (mp_raise_NotImplementedError("mp_hal_pin_od_low"))
 #define mp_hal_pin_od_high(p)      (mp_raise_NotImplementedError("mp_hal_pin_od_high"))

py/mphal.h

@@ -26,6 +26,7 @@
 #ifndef MICROPY_INCLUDED_PY_MPHAL_H
 #define MICROPY_INCLUDED_PY_MPHAL_H
 
+#include <stdint.h>
 #include "py/mpconfig.h"
 
 #ifdef MICROPY_MPHALPORT_H
@@ -74,6 +75,11 @@ mp_uint_t mp_hal_ticks_us(void);
 mp_uint_t mp_hal_ticks_cpu(void);
 #endif
 
+#ifndef mp_hal_time_ns
+// Nanoseconds since 1970/1/1.
+uint64_t mp_hal_time_ns(void);
+#endif
+
 // If port HAL didn't define its own pin API, use generic
 // "virtual pin" API from the core.
 #ifndef mp_hal_pin_obj_t