diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index cfde4b7d0..4fafda64e 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -3610,7 +3610,7 @@
 //#define MBEDTLS_PLATFORM_SETBUF_MACRO      setbuf /**< Default setbuf macro to use, can be undefined */
 //#define MBEDTLS_PLATFORM_TIME_MACRO            time /**< Default time macro to use, can be undefined. MBEDTLS_HAVE_TIME must be enabled */
 //#define MBEDTLS_PLATFORM_TIME_TYPE_MACRO       time_t /**< Default time macro to use, can be undefined. MBEDTLS_HAVE_TIME must be enabled */
-//#define MBEDTLS_PLATFORM_MS_TIME_TYPE_MACRO   signed long long /**< Default millionseconds time macro to use, can be undefined. MBEDTLS_HAVE_TIME must be enabled. It MUST be signed 64bit integer at least */
+//#define MBEDTLS_PLATFORM_MS_TIME_TYPE_MACRO   int64_t /**< Default millionseconds time macro to use, can be undefined. MBEDTLS_HAVE_TIME must be enabled. It MUST be signed 64bit integer at least */
 //#define MBEDTLS_PLATFORM_FPRINTF_MACRO      fprintf /**< Default fprintf macro to use, can be undefined */
 //#define MBEDTLS_PLATFORM_PRINTF_MACRO        printf /**< Default printf macro to use, can be undefined */
 /* Note: your snprintf must correctly zero-terminate the buffer! */
diff --git a/include/mbedtls/platform_time.h b/include/mbedtls/platform_time.h
index 246120ed3..3158e2a83 100644
--- a/include/mbedtls/platform_time.h
+++ b/include/mbedtls/platform_time.h
@@ -49,14 +49,14 @@ typedef int64_t mbedtls_ms_time_t;
 /**
  * \brief   Get time in milliseconds.
  *
- * \return Current time in milliseconds which is monotonically increasing.
+ * \return Monotonically-increasing current time in milliseconds.
  *
- * \note If MBEDTLS_PLATFORM_MS_TIME_ALT defined, users can provide their own
- *       implementation.
+ * \note Define MBEDTLS_PLATFORM_MS_TIME_ALT to be able to provide an
+ *       alternative implementation
  *
- * \warning This function is used for time difference only. The start time is
- *          not defined. A well defined time function is not required in
- *          TLS negotiation.
+ * \warning This function returns a monotonically-increasing time value from a
+ *          start time that will differ from platform to platform, and possibly
+ *          from run to run of the process.
  *
  */
 mbedtls_ms_time_t mbedtls_ms_time(void);