diff --git a/common/hw-gfx-gma-transcoder.ads b/common/hw-gfx-gma-transcoder.ads
new file mode 100644
index 0000000..aa67eb4
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+++ b/common/hw-gfx-gma-transcoder.ads
@@ -0,0 +1,114 @@
+--
+-- 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; either version 2 of the License, or
+-- (at your option) any later version.
+--
+-- 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.GFX.GMA.Registers;
+
+private package HW.GFX.GMA.Transcoder
+is
+
+   procedure Setup (Pipe : Pipe_Index; Port_Cfg : Port_Config);
+   procedure On (Pipe : Pipe_Index; Port_Cfg : Port_Config; Dither : Boolean);
+
+   procedure Off (Pipe : Pipe_Index);
+   procedure Clk_Off (Pipe : Pipe_Index);
+
+   function BPC_Conf (BPC : BPC_Type; Dither : Boolean) return Word32;
+
+private
+
+   type Transcoder_Index is (Trans_EDP, Trans_A, Trans_B, Trans_C);
+
+   type Transcoder_Regs is
+      record
+         HTOTAL         : Registers.Registers_Index;
+         HBLANK         : Registers.Registers_Index;
+         HSYNC          : Registers.Registers_Index;
+         VTOTAL         : Registers.Registers_Index;
+         VBLANK         : Registers.Registers_Index;
+         VSYNC          : Registers.Registers_Index;
+         CONF           : Registers.Registers_Index;
+         DATA_M1        : Registers.Registers_Index;
+         DATA_N1        : Registers.Registers_Index;
+         LINK_M1        : Registers.Registers_Index;
+         LINK_N1        : Registers.Registers_Index;
+         DDI_FUNC_CTL   : Registers.Registers_Index;
+         MSA_MISC       : Registers.Registers_Index;
+         CLK_SEL        : Registers.Registers_Invalid_Index;
+      end record;
+
+   type Transcoder_Array is array (Transcoder_Index) of Transcoder_Regs;
+
+   Transcoders : constant Transcoder_Array :=
+     (Trans_EDP =>
+        (HTOTAL         => Registers.HTOTAL_EDP,
+         HBLANK         => Registers.HBLANK_EDP,
+         HSYNC          => Registers.HSYNC_EDP,
+         VTOTAL         => Registers.VTOTAL_EDP,
+         VBLANK         => Registers.VBLANK_EDP,
+         VSYNC          => Registers.VSYNC_EDP,
+         CONF           => Registers.PIPE_EDP_CONF,
+         DATA_M1        => Registers.PIPE_EDP_DATA_M1,
+         DATA_N1        => Registers.PIPE_EDP_DATA_N1,
+         LINK_M1        => Registers.PIPE_EDP_LINK_M1,
+         LINK_N1        => Registers.PIPE_EDP_LINK_N1,
+         DDI_FUNC_CTL   => Registers.PIPE_EDP_DDI_FUNC_CTL,
+         MSA_MISC       => Registers.PIPE_EDP_MSA_MISC,
+         CLK_SEL        => Registers.Invalid_Register),
+      Trans_A =>
+        (HTOTAL         => Registers.HTOTAL_A,
+         HBLANK         => Registers.HBLANK_A,
+         HSYNC          => Registers.HSYNC_A,
+         VTOTAL         => Registers.VTOTAL_A,
+         VBLANK         => Registers.VBLANK_A,
+         VSYNC          => Registers.VSYNC_A,
+         CONF           => Registers.PIPEACONF,
+         DATA_M1        => Registers.PIPEA_DATA_M1,
+         DATA_N1        => Registers.PIPEA_DATA_N1,
+         LINK_M1        => Registers.PIPEA_LINK_M1,
+         LINK_N1        => Registers.PIPEA_LINK_N1,
+         DDI_FUNC_CTL   => Registers.PIPEA_DDI_FUNC_CTL,
+         MSA_MISC       => Registers.PIPEA_MSA_MISC,
+         CLK_SEL        => Registers.TRANSA_CLK_SEL),
+      Trans_B =>
+        (HTOTAL         => Registers.HTOTAL_B,
+         HBLANK         => Registers.HBLANK_B,
+         HSYNC          => Registers.HSYNC_B,
+         VTOTAL         => Registers.VTOTAL_B,
+         VBLANK         => Registers.VBLANK_B,
+         VSYNC          => Registers.VSYNC_B,
+         CONF           => Registers.PIPEBCONF,
+         DATA_M1        => Registers.PIPEB_DATA_M1,
+         DATA_N1        => Registers.PIPEB_DATA_N1,
+         LINK_M1        => Registers.PIPEB_LINK_M1,
+         LINK_N1        => Registers.PIPEB_LINK_N1,
+         DDI_FUNC_CTL   => Registers.PIPEB_DDI_FUNC_CTL,
+         MSA_MISC       => Registers.PIPEB_MSA_MISC,
+         CLK_SEL        => Registers.TRANSB_CLK_SEL),
+      Trans_C =>
+        (HTOTAL         => Registers.HTOTAL_C,
+         HBLANK         => Registers.HBLANK_C,
+         HSYNC          => Registers.HSYNC_C,
+         VTOTAL         => Registers.VTOTAL_C,
+         VBLANK         => Registers.VBLANK_C,
+         VSYNC          => Registers.VSYNC_C,
+         CONF           => Registers.PIPECCONF,
+         DATA_M1        => Registers.PIPEC_DATA_M1,
+         DATA_N1        => Registers.PIPEC_DATA_N1,
+         LINK_M1        => Registers.PIPEC_LINK_M1,
+         LINK_N1        => Registers.PIPEC_LINK_N1,
+         DDI_FUNC_CTL   => Registers.PIPEC_DDI_FUNC_CTL,
+         MSA_MISC       => Registers.PIPEC_MSA_MISC,
+         CLK_SEL        => Registers.TRANSC_CLK_SEL));
+
+end HW.GFX.GMA.Transcoder;