gma: Add G45 support

The following ports are implemented: HDMI/DVI, VGA, LVDS and DP.

Tested with gfx_test and coreboot on a Thinkpad X200 (GM45).

Change-Id: Ifc05a1516329a61772af84558e5bfceb4d4ca277
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/21295
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: Nico Huber <nico.h@gmx.de>
diff --git a/common/g45/hw-gfx-gma-plls.ads b/common/g45/hw-gfx-gma-plls.ads
new file mode 100644
index 0000000..09d6946
--- /dev/null
+++ b/common/g45/hw-gfx-gma-plls.ads
@@ -0,0 +1,40 @@
+--
+-- 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.
+--
+
+private package HW.GFX.GMA.PLLs
+with
+   Abstract_State => (State with Part_Of => GMA.State)
+is
+
+   -- XXX: Types should be private (but that triggers a bug in SPARK GPL 2016)
+   type T is (Invalid_PLL, DPLL_A, DPLL_B);
+   subtype DPLLs is T range DPLL_A .. DPLL_B;
+   Invalid : constant T := Invalid_PLL;
+
+   procedure Initialize
+   with
+      Global => (Output => State);
+
+   procedure Alloc
+     (Port_Cfg : in     Port_Config;
+      PLL      :    out T;
+      Success  :    out Boolean);
+
+   procedure Free (PLL : T);
+
+   procedure All_Off;
+
+   function Register_Value (PLL : T) return Word32;
+
+end HW.GFX.GMA.PLLs;