mediatek/mt8173: Add soc ARM Trusted Firmware support

We define a mechanism to pass board specific parameters to BL31. The
idea is BL31 doesn't need to have the board revision knowledge, it
only needs to process the board specific parameters to initialize and
control specific hardware. In this way, we can support different boards
with same BL31 binary.

[pg: add the code, but don't actually enable the support yet, because it
relies on code that still needs to be merged to arm-trusted-firmware.]

BRANCH=none
BUG=none
TEST=booted on oak-rev2 and oak-rev3 boards, and confirmed they got
     different board arguments in ARM TF

Change-Id: I9ea3ce6c8f79dd427be67f30bc940d2038173b81
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 0f9a4a2776110c5ddc113f0d605d4337d5773ace
Original-Change-Id: I985d9555238f5ac5385e126479140b772b36bac8
Original-Signed-off-by: Jimmy Huang <jimmy.huang@mediatek.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/292678
Original-Commit-Ready: Yidi Lin <yidi.lin@mediatek.com>
Original-Tested-by: Yidi Lin <yidi.lin@mediatek.com>
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/13100
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/soc/mediatek/mt8173/Makefile.inc

@@ -73,6 +73,11 @@ ramstage-y += rtc.c
 
 ramstage-y += usb.c
 
+ramstage-$(CONFIG_ARM64_USE_ARM_TRUSTED_FIRMWARE) += bl31_plat_params.c
+
+BL31_MAKEARGS += PLAT=mt8173 MEDIATEK_MEM_CONFIG=SRAM_192K MEDIATEK_DA9212=1 \
+		 MEDIATEK_MT6311=1
+
 ################################################################################
 
 # Generate the actual coreboot bootblock code

src/soc/mediatek/mt8173/bl31_plat_params.c

@@ -0,0 +1,30 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2015 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 <arm_tf.h>
+#include <assert.h>
+#include <soc/bl31_plat_params.h>
+
+static struct bl31_plat_param *plat_params;
+
+void register_bl31_param(struct bl31_plat_param *param)
+{
+	param->next = (void *)plat_params;
+	plat_params = param;
+}
+
+void *soc_get_bl31_plat_params(bl31_params_t *bl31_params)
+{
+	return (void *)plat_params;
+}

src/soc/mediatek/mt8173/include/soc/bl31_plat_params.h

@@ -0,0 +1,24 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2015 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.
+ */
+#ifndef __BL31_PLAT_PARAMS_H__
+#define __BL31_PLAT_PARAMS_H__
+
+#if IS_ENABLED(CONFIG_ARM64_USE_ARM_TRUSTED_FIRMWARE)
+#include <arm-trusted-firmware/plat/mediatek/mt8173/include/plat_params.h>
+
+void register_bl31_param(struct bl31_plat_param *param);
+#endif
+
+#endif /* __BL31_PLAT_PARAMS_H__ */