diff --git a/common/hw-time.adb b/common/hw-time.adb
new file mode 100644
index 0000000..3162de1
--- /dev/null
+++ b/common/hw-time.adb
@@ -0,0 +1,105 @@
+--
+-- Copyright (C) 2015-2016 secunet Security Networks AG
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; version 2 of the License.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+
+with HW;
+with HW.Time.Timer;
+
+use type HW.Word64;
+
+package body HW.Time
+   with Refined_State => (State => (Timer.Timer_State, Timer.Abstract_Time))
+is
+
+   function Now return T
+   with
+      Refined_Global => (Input => Timer.Abstract_Time)
+   is
+      Current : constant T := Timer.Raw_Value_Min;
+   begin
+      return Current;
+   end Now;
+
+   function US_From_Now (US : Natural) return T
+   with
+      Refined_Global => (Input => (Timer.Abstract_Time, Timer.Timer_State))
+   is
+      Current : constant T := Timer.Raw_Value_Max;
+   begin
+      return Current + (T (US) * Timer.Hz + 999_999) / 1_000_000;
+   end US_From_Now;
+
+   function MS_From_Now (MS : Natural) return T
+   with
+      Refined_Global => (Input => (Timer.Abstract_Time, Timer.Timer_State))
+   is
+      Current : constant T := Timer.Raw_Value_Max;
+   begin
+      return Current + (T (MS) * Timer.Hz + 999) / 1_000;
+   end MS_From_Now;
+
+   function Now_US return Int64
+   with
+      Refined_Global => (Input => (Timer.Abstract_Time, Timer.Timer_State))
+   is
+      MHz : constant T := Timer.Hz / 1_000_000;
+      Current : constant T := Timer.Raw_Value_Min;
+   begin
+      return Int64 ((Current and (2 ** 63 - 1)) / (if MHz = 0 then 1 else MHz));
+   end Now_US;
+
+   ----------------------------------------------------------------------------
+
+   procedure Delay_Until (Deadline : T)
+   with
+      Refined_Global => (Input => (Timer.Abstract_Time))
+   is
+      Current: T;
+   begin
+      loop
+         Current := Timer.Raw_Value_Min;
+         exit when Current >= Deadline;
+      end loop;
+   end Delay_Until;
+
+   procedure U_Delay (US : Natural)
+   with
+      Refined_Global => (Input => (Timer.Abstract_Time, Timer.Timer_State))
+   is
+      Deadline : constant T := US_From_Now (US);
+   begin
+      Delay_Until (Deadline);
+   end U_Delay;
+
+   procedure M_Delay (MS : Natural)
+   with
+      Refined_Global => (Input => (Timer.Abstract_Time, Timer.Timer_State))
+   is
+      Deadline : constant T := MS_From_Now (MS);
+   begin
+      Delay_Until (Deadline);
+   end M_Delay;
+
+   ----------------------------------------------------------------------------
+
+   function Timed_Out (Deadline : T) return Boolean
+   with
+      Refined_Global => (Input => (Timer.Abstract_Time))
+   is
+      Current : constant T := Timer.Raw_Value_Min;
+   begin
+      return Current >= Deadline;
+   end Timed_Out;
+
+end HW.Time;
+
+--  vim: set ts=8 sts=3 sw=3 et: