diff --git a/common/haswell_shared/hw-gfx-gma-port_detect.adb b/common/haswell_shared/hw-gfx-gma-port_detect.adb
new file mode 100644
index 0000000..0becd2c
--- /dev/null
+++ b/common/haswell_shared/hw-gfx-gma-port_detect.adb
@@ -0,0 +1,189 @@
+--
+-- Copyright (C) 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.GFX.GMA.Config;
+with HW.GFX.GMA.Registers;
+
+package body HW.GFX.GMA.Port_Detect
+is
+
+   PCH_ADPA_CRT_HPD_CHANNEL_MASK       : constant := 3 * 2 ** 24;
+   PCH_ADPA_CRT_HPD_ENABLE             : constant := 1 * 2 ** 23;
+
+   SFUSE_STRAP_CRT_DAC_CAP_DISABLE     : constant := 1 * 2 **  6;
+
+   HOTPLUG_CTL_DDI_A_HPD_INPUT_ENABLE  : constant := 1 * 2 **  4;
+   HOTPLUG_CTL_DDI_A_HPD_STATUS        : constant := 3 * 2 **  0;
+   HOTPLUG_CTL_DDI_A_HPD_LONG_DETECT   : constant := 1 * 2 **  1;
+
+   SHOTPLUG_CTL_DETECT_MASK            : constant := 16#0303_0303#;
+
+   type Digital_Port_Value is array (Digital_Port) of Word32;
+   DDI_PORT_DETECTED : constant Digital_Port_Value :=
+     (DIGI_B => 1 * 2 **  2,
+      DIGI_C => 1 * 2 **  1,
+      DIGI_D => 1 * 2 **  0,
+      DIGI_A => 1 * 2 **  0,
+      others => 0);
+   SHOTPLUG_CTL_HPD_INPUT_ENABLE : constant Digital_Port_Value :=
+     (DIGI_B => 1 * 2 **  4,
+      DIGI_C => 1 * 2 ** 12,
+      DIGI_D => 1 * 2 ** 20,
+      DIGI_A => 1 * 2 ** 28,
+      others => 0);
+   SHOTPLUG_CTL_HPD_STATUS : constant Digital_Port_Value :=
+     (DIGI_B => 3 * 2 **  0,
+      DIGI_C => 3 * 2 **  8,
+      DIGI_D => 3 * 2 ** 16,
+      DIGI_A => 3 * 2 ** 24,
+      others => 0);
+   SHOTPLUG_CTL_LONG_DETECT : constant Digital_Port_Value :=
+     (DIGI_B => 1 * 2 **  1,
+      DIGI_C => 1 * 2 **  9,
+      DIGI_D => 1 * 2 ** 17,
+      DIGI_A => 1 * 2 ** 25,
+      others => 0);
+
+   procedure Initialize
+   is
+      DAC_Disabled,
+      Internal_Detected,
+      DDI_Detected : Boolean;
+
+      Last_Digital_Port : constant Digital_Port :=
+        (if Config.Has_DDI_D then DIGI_D else DIGI_C);
+
+      subtype Ext_Digital_Port is
+         Digital_Port range DIGI_B .. DIGI_D;
+      type Digital_Port_To_GMA_Port is array (Ext_Digital_Port) of Port_Type;
+      To_HDMI_Port : constant Digital_Port_To_GMA_Port :=
+        (DIGI_B => Digital1,
+         DIGI_C => Digital2,
+         DIGI_D => Digital3);
+      To_DP_Port : constant Digital_Port_To_GMA_Port :=
+        (DIGI_B => DP1,
+         DIGI_C => DP2,
+         DIGI_D => DP3);
+   begin
+      if Config.Has_PCH_DAC then
+         -- PCH_DAC (_A)
+         Registers.Is_Set_Mask
+           (Register => Registers.SFUSE_STRAP,
+            Mask     => SFUSE_STRAP_CRT_DAC_CAP_DISABLE,
+            Result   => DAC_Disabled);
+         if not DAC_Disabled then
+            Registers.Set_Mask
+              (Register => Registers.PCH_ADPA,
+               Mask     => PCH_ADPA_CRT_HPD_CHANNEL_MASK or   -- clear status
+                           PCH_ADPA_CRT_HPD_ENABLE);
+         end if;
+         Config.Valid_Port (Analog) := not DAC_Disabled;
+      end if;
+
+      if Config.Internal_Is_EDP then
+         -- DDI_A
+         Registers.Is_Set_Mask
+           (Register => Registers.DDI_BUF_CTL_A,
+            Mask     => DDI_PORT_DETECTED (DIGI_A),
+            Result   => Internal_Detected);
+         if Internal_Detected then
+            if Config.Has_HOTPLUG_CTL then
+               Registers.Set_Mask
+                 (Register => Registers.HOTPLUG_CTL,
+                  Mask     => HOTPLUG_CTL_DDI_A_HPD_INPUT_ENABLE or
+                              HOTPLUG_CTL_DDI_A_HPD_STATUS);   -- clear status
+               if Config.Has_SHOTPLUG_CTL_A then
+                  -- Have to enable south hotplug too on SoCs.
+                  Registers.Unset_And_Set_Mask
+                    (Register    => Registers.SHOTPLUG_CTL,
+                     Mask_Unset  => SHOTPLUG_CTL_DETECT_MASK,
+                     Mask_Set    => SHOTPLUG_CTL_HPD_INPUT_ENABLE (DIGI_A));
+               end if;
+            else
+               Registers.Unset_And_Set_Mask
+                 (Register    => Registers.SHOTPLUG_CTL,
+                  Mask_Unset  => SHOTPLUG_CTL_DETECT_MASK,
+                  Mask_Set    => SHOTPLUG_CTL_HPD_INPUT_ENABLE (DIGI_A) or
+                                 SHOTPLUG_CTL_HPD_STATUS (DIGI_A));  -- clear
+            end if;
+         end if;
+      else
+         Internal_Detected := False;
+      end if;
+      Config.Valid_Port (Internal) := Internal_Detected;
+
+      -- DDI_[BCD]
+      for Port in Ext_Digital_Port range DIGI_B .. Last_Digital_Port loop
+         Registers.Is_Set_Mask
+           (Register => Registers.SFUSE_STRAP,
+            Mask     => DDI_PORT_DETECTED (Port),
+            Result   => DDI_Detected);
+         Config.Valid_Port (To_HDMI_Port (Port)) :=
+            Config.Valid_Port (To_HDMI_Port (Port)) and DDI_Detected;
+         Config.Valid_Port (To_DP_Port (Port)) :=
+            Config.Valid_Port (To_DP_Port (Port)) and DDI_Detected;
+
+         if DDI_Detected then
+            Registers.Unset_And_Set_Mask
+              (Register    => Registers.SHOTPLUG_CTL,
+               Mask_Unset  => SHOTPLUG_CTL_DETECT_MASK,
+               Mask_Set    => SHOTPLUG_CTL_HPD_INPUT_ENABLE (Port) or
+                              SHOTPLUG_CTL_HPD_STATUS (Port)); -- clear status
+         else
+            Registers.Unset_Mask
+              (Register => Registers.SHOTPLUG_CTL,
+               Mask     => SHOTPLUG_CTL_DETECT_MASK or
+                           SHOTPLUG_CTL_HPD_INPUT_ENABLE (Port));
+         end if;
+      end loop;
+   end Initialize;
+
+   procedure Hotplug_Detect (Port_Cfg : in Port_Config; Detected : out Boolean)
+   is
+      Ctl32 : Word32;
+   begin
+      if Port_Cfg.Display = VGA then
+         Registers.Read (Registers.PCH_ADPA, Ctl32, Verbose => False);
+         Ctl32 := Ctl32 and PCH_ADPA_CRT_HPD_CHANNEL_MASK;
+         Detected := Ctl32 = PCH_ADPA_CRT_HPD_CHANNEL_MASK;
+         if Ctl32 /= 0 then
+            Registers.Set_Mask
+              (Register => Registers.PCH_ADPA,
+               Mask     => PCH_ADPA_CRT_HPD_CHANNEL_MASK);
+         end if;
+      elsif Config.Has_HOTPLUG_CTL and then Port_Cfg.Port = DIGI_A then
+         Registers.Read (Registers.HOTPLUG_CTL, Ctl32, Verbose => False);
+         Detected := (Ctl32 and HOTPLUG_CTL_DDI_A_HPD_LONG_DETECT) /= 0;
+
+         if (Ctl32 and HOTPLUG_CTL_DDI_A_HPD_STATUS) /= 0 then
+            Registers.Set_Mask
+              (Register => Registers.HOTPLUG_CTL,
+               Mask     => HOTPLUG_CTL_DDI_A_HPD_STATUS);
+         end if;
+      elsif Port_Cfg.Port in DIGI_A .. DIGI_D then
+         Registers.Read (Registers.SHOTPLUG_CTL, Ctl32, Verbose => False);
+         Detected :=
+           (Ctl32 and SHOTPLUG_CTL_LONG_DETECT (Port_Cfg.Port)) /= 0;
+
+         if (Ctl32 and SHOTPLUG_CTL_HPD_STATUS (Port_Cfg.Port)) /= 0 then
+            Registers.Unset_And_Set_Mask
+              (Register    => Registers.SHOTPLUG_CTL,
+               Mask_Unset  => SHOTPLUG_CTL_DETECT_MASK,
+               Mask_Set    => SHOTPLUG_CTL_HPD_STATUS (Port_Cfg.Port));
+         end if;
+      else
+         Detected := False;
+      end if;
+   end Hotplug_Detect;
+
+end HW.GFX.GMA.Port_Detect;