mb/lenovo/x230: introduce EDP variant

There is a modification for the x230 which uses the 2nd DP from the
dock as the integrated panel's connection, which allows using a custom
eDP panel instead of the stock LVDS display.

There are several adapter boards present on the market and all of them
use the same method of enabling the custom eDP panel.

To make this work with coreboot, the internal LVDS connector should be
disabled in libgfxinit. Additionally, VBT has been modified to keep
brightness controls functional on the adapter boards that use LVDS for
the job.

The modifications done to the VBT are:
- Remove the LVDS port entry.
- Move the DP-3 (which is the 2nd DP on the dock) entry to the first
  position on the list.
- Set the DP-3 as internally connected.

This has been reported to work with the following panels:
- LP125WF2-SPB4 (1920*1080, 12.5")
- LQ125T1JW02 (2560*1440, 12.5")
- LQ133M1JW21 (1920*1080, 13.3")
- LTN133HL10-201 (1920*1080, 13.3")
- B133HAN04.6 (1920*1080, 13.3")
- B133QAN02.0 (2560*1600, 13.3")

Other eDP panels not on this list should work as well.

Change-Id: I0355d39a61956792e69bccd5274cfc2749d72bf0
Signed-off-by: Alexander Couzens <lynxis@fe80.eu>
Signed-off-by: Felix Singer <felixsinger@posteo.net>
Signed-off-by: Alexei Sorokin <sor.alexei@meowr.ru>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/28950
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>

2 files changed, 21 insertions, 0 deletions

diff --git a/src/mainboard/lenovo/x230/variants/x230_edp/data.vbt b/src/mainboard/lenovo/x230/variants/x230_edp/data.vbt
new file mode 100644
index 0000000000..13384d4557
--- /dev/null
+++ b/src/mainboard/lenovo/x230/variants/x230_edp/data.vbt
diff --git a/src/mainboard/lenovo/x230/variants/x230_edp/gma-mainboard.ads b/src/mainboard/lenovo/x230/variants/x230_edp/gma-mainboard.ads
new file mode 100644
index 0000000000..f7cf0bc264
--- /dev/null
+++ b/src/mainboard/lenovo/x230/variants/x230_edp/gma-mainboard.ads
@@ -0,0 +1,21 @@
+-- SPDX-License-Identifier: GPL-2.0-or-later
+
+with HW.GFX.GMA;
+with HW.GFX.GMA.Display_Probing;
+
+use HW.GFX.GMA;
+use HW.GFX.GMA.Display_Probing;
+
+private package GMA.Mainboard is
+
+   ports : constant Port_List :=
+     (DP1,
+      DP2,
+      DP3,
+      HDMI1,
+      HDMI2,
+      HDMI3,
+      Analog,
+      others => Disabled);
+
+end GMA.Mainboard;