diff --git a/common/i945/hw-gfx-gma-power_and_clocks.adb b/common/i945/hw-gfx-gma-power_and_clocks.adb
index e18d1e3..23d5476 100644
--- a/common/i945/hw-gfx-gma-power_and_clocks.adb
+++ b/common/i945/hw-gfx-gma-power_and_clocks.adb
@@ -128,4 +128,9 @@
       CDClk_Switch := False;
    end Limit_Dotclocks;
 
+   procedure Power_Up (Port : Active_Port_Type; Success : out Boolean) is
+   begin
+      Success := True;
+   end Power_Up;
+
 end HW.GFX.GMA.Power_And_Clocks;
diff --git a/common/i945/hw-gfx-gma-power_and_clocks.ads b/common/i945/hw-gfx-gma-power_and_clocks.ads
index cad2898..10e9d53 100644
--- a/common/i945/hw-gfx-gma-power_and_clocks.ads
+++ b/common/i945/hw-gfx-gma-power_and_clocks.ads
@@ -34,6 +34,10 @@
 
    procedure Power_Set_To (Configs : Pipe_Configs) is null;
 
+   pragma Warnings (GNATprove, Off, "unused variable ""Port""",
+                    Reason => "Needed for a common interface");
+   procedure Power_Up (Port : Active_Port_Type; Success : out Boolean);
+   pragma Warnings (GNATprove, On, "unused variable ""Port""");
    procedure Power_Up (Old_Configs, New_Configs : Pipe_Configs) is null;
 
    procedure Power_Down (Old_Configs, Tmp_Configs, New_Configs : Pipe_Configs)