From fc8cefeadefca5e4568f4266a619961537c107a5 Mon Sep 17 00:00:00 2001
From: Bartosz Bilas <b.bilas@grinn-global.com>
Date: Thu, 2 Oct 2025 13:08:24 +0200
Subject: [PATCH] plat: mediatek: use libdram to pass actual memory size to
 U-Boot

Since libdram can obtain the actual memory size at runtime, make it possible
to pass this value to U-Boot. This allows the bootloader to adapt to boards
with different DRAM sizes without requiring manual configuration.
---
 plat/mediatek/mt8188/bl2_plat_setup.c          |  5 +++++
 plat/mediatek/mt8188/drivers/libdram/libdram.h | 14 ++++++++++++++
 plat/mediatek/mt8188/drivers/libdram/rules.mk  | 12 ++++++++++++
 plat/mediatek/mt8188/include/platform_def.h    |  2 ++
 plat/mediatek/mt8188/platform_bl2.mk           |  1 +
 5 files changed, 34 insertions(+)
 create mode 100644 plat/mediatek/mt8188/drivers/libdram/libdram.h
 create mode 100644 plat/mediatek/mt8188/drivers/libdram/rules.mk

diff --git a/plat/mediatek/mt8188/bl2_plat_setup.c b/plat/mediatek/mt8188/bl2_plat_setup.c
index 70a0564ff..8e6e33e4d 100644
--- a/plat/mediatek/mt8188/bl2_plat_setup.c
+++ b/plat/mediatek/mt8188/bl2_plat_setup.c
@@ -33,6 +33,7 @@
 #if defined(PLAT_AB_BOOT_ENABLE)
 #include <mtk_ab.h>
 #endif
+#include "libdram.h"
 
 void pwrap_init(void);
 void mt_mem_init(void);
@@ -396,6 +397,10 @@ void bl2_platform_setup(void)
 	load_partition_table(GPT_IMAGE_ID);
 	blkdev_set_dramk_data_offset(get_part_addr("dramk"));
 	mt_mem_init();
+
+	BOOT_ARGUMENT->magic_number = BOOT_ARGUMENT_MAGIC;
+	BOOT_ARGUMENT->dram_size = platform_memory_size();
+
 	/* change emmc read buffer to DRAM */
 	boot_dev_spec->buffer.offset = 0x41000000;
 	boot_dev_spec->buffer.length = 0x1000000;
diff --git a/plat/mediatek/mt8188/drivers/libdram/libdram.h b/plat/mediatek/mt8188/drivers/libdram/libdram.h
new file mode 100644
index 000000000..311d3a25c
--- /dev/null
+++ b/plat/mediatek/mt8188/drivers/libdram/libdram.h
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2025 Grinn sp. z o.o
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef LIBDRAM_H
+#define LIBDRAM_H
+
+#include <stdint.h>
+
+unsigned long long platform_memory_size(void);
+
+#endif /* LIBDRAM_H */
diff --git a/plat/mediatek/mt8188/drivers/libdram/rules.mk b/plat/mediatek/mt8188/drivers/libdram/rules.mk
new file mode 100644
index 000000000..38f23c3dd
--- /dev/null
+++ b/plat/mediatek/mt8188/drivers/libdram/rules.mk
@@ -0,0 +1,12 @@
+#
+# Copyright (c) 2025, Grinn sp. z o.o. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+LOCAL_DIR := $(call GET_LOCAL_DIR)
+
+MODULE := libdram
+
+PLAT_INCLUDES += -I${LOCAL_DIR}/
+$(eval $(call MAKE_MODULE,$(MODULE),$(LOCAL_SRCS-y),$(MTK_BL)))
diff --git a/plat/mediatek/mt8188/include/platform_def.h b/plat/mediatek/mt8188/include/platform_def.h
index 23bc1ad7c..cfa0d3728 100644
--- a/plat/mediatek/mt8188/include/platform_def.h
+++ b/plat/mediatek/mt8188/include/platform_def.h
@@ -303,6 +303,8 @@
 #define BL2_BASE		(0x201000)
 #define BL2_LIMIT		(0x400000)
 
+#define BOOT_ARGUMENT_LOCATION	(0x40000100)
+
 #define MAX_IO_DEVICES			U(3)
 #define MAX_IO_HANDLES			U(4)
 #define MAX_IO_BLOCK_DEVICES			1
diff --git a/plat/mediatek/mt8188/platform_bl2.mk b/plat/mediatek/mt8188/platform_bl2.mk
index a851dc98b..421f2c824 100644
--- a/plat/mediatek/mt8188/platform_bl2.mk
+++ b/plat/mediatek/mt8188/platform_bl2.mk
@@ -25,6 +25,7 @@ BL2_SOURCES += lib/cpus/aarch64/cortex_a55.S \
 	       ${MTK_PLAT}/common/mtk_rgu.c
 
 MODULES-BL2-y += $(MTK_PLAT)/drivers/uart
+MODULES-BL2-y += $(MTK_PLAT_SOC)/drivers/libdram
 MODULES-BL2-y += ${MTK_PLAT}/drivers/wdt
 MODULES-BL2-y += ${MTK_PLAT_SOC}/drivers/pll
 MODULES-BL2-y += $(MTK_PLAT_SOC)/drivers/pmic_bl2