diff --git a/ports/stm32/mbedtls/mbedtls_config.h b/ports/stm32/mbedtls/mbedtls_config.h
index 4140bb514..bdac07339 100644
--- a/ports/stm32/mbedtls/mbedtls_config.h
+++ b/ports/stm32/mbedtls/mbedtls_config.h
@@ -26,6 +26,15 @@
 #ifndef MICROPY_INCLUDED_MBEDTLS_CONFIG_H
 #define MICROPY_INCLUDED_MBEDTLS_CONFIG_H
 
+// Enable mbedtls modules.
+#define MBEDTLS_HAVE_TIME
+#define MBEDTLS_HAVE_TIME_DATE
+
+// Time hook.
+#include <time.h>
+extern time_t stm32_rtctime_seconds(time_t *timer);
+#define MBEDTLS_PLATFORM_TIME_MACRO stm32_rtctime_seconds
+
 // Set MicroPython-specific options.
 #define MICROPY_MBEDTLS_CONFIG_BARE_METAL (1)
 
diff --git a/ports/stm32/mbedtls/mbedtls_port.c b/ports/stm32/mbedtls/mbedtls_port.c
index 5c4f8d0f9..cdfcd172a 100644
--- a/ports/stm32/mbedtls/mbedtls_port.c
+++ b/ports/stm32/mbedtls/mbedtls_port.c
@@ -27,6 +27,11 @@
 #include "rng.h"
 #include "mbedtls_config.h"
 
+#if defined(MBEDTLS_HAVE_TIME) || defined(MBEDTLS_HAVE_TIME_DATE)
+#include "rtc.h"
+#include "shared/timeutils/timeutils.h"
+#endif
+
 int mbedtls_hardware_poll(void *data, unsigned char *output, size_t len, size_t *olen) {
     uint32_t val = 0;
     int n = 0;
@@ -42,3 +47,34 @@ int mbedtls_hardware_poll(void *data, unsigned char *output, size_t len, size_t
     }
     return 0;
 }
+
+#if defined(MBEDTLS_HAVE_TIME)
+time_t stm32_rtctime_seconds(time_t *timer) {
+    rtc_init_finalise();
+    RTC_DateTypeDef date;
+    RTC_TimeTypeDef time;
+    HAL_RTC_GetTime(&RTCHandle, &time, RTC_FORMAT_BIN);
+    HAL_RTC_GetDate(&RTCHandle, &date, RTC_FORMAT_BIN);
+    return timeutils_seconds_since_epoch(2000 + date.Year, date.Month, date.Date, time.Hours, time.Minutes, time.Seconds);
+}
+#endif
+
+#if defined(MBEDTLS_HAVE_TIME_DATE)
+struct tm *gmtime(const time_t *timep) {
+    static struct tm tm;
+    timeutils_struct_time_t tm_buf = {0};
+    timeutils_seconds_since_epoch_to_struct_time(*timep, &tm_buf);
+
+    tm.tm_sec = tm_buf.tm_sec;
+    tm.tm_min = tm_buf.tm_min;
+    tm.tm_hour = tm_buf.tm_hour;
+    tm.tm_mday = tm_buf.tm_mday;
+    tm.tm_mon = tm_buf.tm_mon - 1;
+    tm.tm_year = tm_buf.tm_year - 1900;
+    tm.tm_wday = tm_buf.tm_wday;
+    tm.tm_yday = tm_buf.tm_yday;
+    tm.tm_isdst = -1;
+
+    return &tm;
+}
+#endif