lenovo/t420: Add new port

This is based on t420s. Tested on a T420 without discrete GPU.
There is no support for nvidia gpu and optimus.

Signed-off-by: Nicolas Reinecke <nr@das-labor.org>
Tested-by: Iru Cai <mytbk920423@gmail.com>
Change-Id: Ie9405966e56180ac1c43a3c5b83181ee500177c8
Reviewed-on: https://review.coreboot.org/11765
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
diff --git a/src/mainboard/lenovo/t420/dsdt.asl b/src/mainboard/lenovo/t420/dsdt.asl
new file mode 100644
index 0000000..aaa0338
--- /dev/null
+++ b/src/mainboard/lenovo/t420/dsdt.asl
@@ -0,0 +1,64 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2007-2009 coresystems GmbH
+ * Copyright (C) 2011 The ChromiumOS Authors.  All rights reserved.
+ * Copyright (C) 2014 Vladimir Serbinenko
+ *
+ * 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.
+ */
+
+#define THINKPAD_EC_GPE 17
+#define BRIGHTNESS_UP \_SB.PCI0.GFX0.INCB
+#define BRIGHTNESS_DOWN \_SB.PCI0.GFX0.DECB
+#define ACPI_VIDEO_DEVICE \_SB.PCI0.GFX0
+#define EC_LENOVO_H8_ME_WORKAROUND 1
+
+DefinitionBlock(
+	"dsdt.aml",
+	"DSDT",
+	0x02,		// DSDT revision: ACPI v2.0
+	"COREv4",	// OEM id
+	"COREBOOT",	// OEM table id
+	0x20110725	// OEM revision
+)
+{
+	#include <southbridge/intel/bd82x6x/acpi/platform.asl>
+
+	// Some generic macros
+	#include "acpi/platform.asl"
+
+	// global NVS and variables
+	#include <southbridge/intel/bd82x6x/acpi/globalnvs.asl>
+
+	#include <cpu/intel/model_206ax/acpi/cpu.asl>
+
+	Scope (\_SB) {
+		Device (PCI0)
+		{
+			#include <northbridge/intel/sandybridge/acpi/sandybridge.asl>
+			#include <southbridge/intel/bd82x6x/acpi/pch.asl>
+			#include <southbridge/intel/bd82x6x/acpi/default_irq_route.asl>
+
+			#include <drivers/intel/gma/acpi/default_brightness_levels.asl>
+		}
+	}
+
+	/*
+	 * LPC Trusted Platform Module
+	 */
+	Scope (\_SB.PCI0.LPCB)
+	{
+		#include <drivers/pc80/tpm/acpi/tpm.asl>
+	}
+
+	/* Chipset specific sleep states */
+	#include <southbridge/intel/bd82x6x/acpi/sleepstates.asl>
+}