mediatek/mt8183: Add SAMSUNG 4GB LPDDR4X discrete DDR support

BUG=b:80501386
BRANCH=none
TEST=Boots correctly and stress test passes on Kukui.

Change-Id: I27164f0909edb9d9398835e292fb845f0e342391
Signed-off-by: Huayang Duan <huayang.duan@mediatek.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34532
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Huayang Duan <huayang.duan@mediatek.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/kukui/sdram_configs.c

@@ -26,6 +26,7 @@ static const char *const sdram_configs[] = {
 	[5] = "sdram-lpddr4x-MT29VZZZAD8DQKSL-4GB",
 	[6] = "sdram-lpddr4x-KMDV6001DA-B620-4GB",
 	[7] = "sdram-lpddr4x-SDADA4CR-128G-4GB",
+	[8] = "sdram-lpddr4x-K4UBE3D4AA-MGCL-4GB",
 };
 
 static struct sdram_params params;

src/mainboard/google/kukui/sdram_params/Makefile.inc

@@ -1,4 +1,5 @@
 sdram-params :=
+sdram-params += sdram-lpddr4x-K4UBE3D4AA-MGCL-4GB
 sdram-params += sdram-lpddr4x-H9HCNNNCPMALHR-4GB
 sdram-params += sdram-lpddr4x-MT53E1G32D4NQ-4GB
 sdram-params += sdram-lpddr4x-KMDH6001DA-B422-4GB

src/mainboard/google/kukui/sdram_params/sdram-lpddr4x-K4UBE3D4AA-MGCL-4GB.c

@@ -0,0 +1,41 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 MediaTek Inc.
+ *
+ * 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.
+ */
+
+#include <soc/emi.h>
+
+struct sdram_params params = {
+	.impedance = {
+		[ODT_OFF] = {0x9, 0x7, 0x0, 0xF},
+		[ODT_ON] = {0xB, 0x9, 0x0, 0xE}
+	},
+	.wr_level = {
+		[CHANNEL_A] = { {0x22, 0x1C}, {0x23, 0x1D} },
+		[CHANNEL_B] = { {0x26, 0x23}, {0x26, 0x23} }
+	},
+	.cbt_cs = {
+		[CHANNEL_A] = {0x6, 0x5},
+		[CHANNEL_B] = {0x6, 0x6}
+	},
+	.cbt_mr12 = {
+		[CHANNEL_A] = {0x56, 0x58},
+		[CHANNEL_B] = {0x58, 0x56}
+	},
+	.emi_cona_val = 0xF053F154,
+	.emi_conh_val = 0x44440003,
+	.emi_conf_val = 0x00421000,
+	.chn_emi_cona_val = {0x0444F051, 0x0444F051},
+	.cbt_mode_extern = CBT_NORMAL_MODE,
+	.delay_cell_unit = 868,
+};