genio: mt8195: atf: patch: add TF-A RAM size autodetection pass to bl33

- With this, bl2 will pass down the DRAM size it gets from libdram
  down to bl33 (u-boot proper) via a magic location
- This is a rework of the implementation for another MTK plat (GRINN)
This commit is contained in:
Ricardo Pardini 2026-01-04 02:02:35 +01:00 committed by Igor
parent ca4fe3da9a
commit 5911f02880

View File

@ -0,0 +1,111 @@
From 6ea06df6886453c312c0a7094f46372cb9803106 Mon Sep 17 00:00:00 2001
From: Ricardo Pardini <ricardo@pardini.net>
Date: Sun, 4 Jan 2026 01:56:47 +0100
Subject: [PATCH] plat: mediatek: mt8195: 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.
All credit to Bartosz Bilas' work for the mt8188.
Signed-off-by: Ricardo Pardini <ricardo@pardini.net>
---
plat/mediatek/mt8195/bl2_plat_setup.c | 5 +++++
plat/mediatek/mt8195/drivers/libdram/libdram.h | 14 ++++++++++++++
plat/mediatek/mt8195/drivers/libdram/rules.mk | 12 ++++++++++++
plat/mediatek/mt8195/include/platform_def.h | 2 ++
plat/mediatek/mt8195/platform.mk | 1 +
5 files changed, 34 insertions(+)
create mode 100644 plat/mediatek/mt8195/drivers/libdram/libdram.h
create mode 100644 plat/mediatek/mt8195/drivers/libdram/rules.mk
diff --git a/plat/mediatek/mt8195/bl2_plat_setup.c b/plat/mediatek/mt8195/bl2_plat_setup.c
index 85e524827..ea157d885 100644
--- a/plat/mediatek/mt8195/bl2_plat_setup.c
+++ b/plat/mediatek/mt8195/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);
@@ -429,6 +430,10 @@ 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 storage read buffer to DRAM */
boot_dev_spec->buffer.offset = 0x41000000;
boot_dev_spec->buffer.length = 0x1000000;
diff --git a/plat/mediatek/mt8195/drivers/libdram/libdram.h b/plat/mediatek/mt8195/drivers/libdram/libdram.h
new file mode 100644
index 000000000..311d3a25c
--- /dev/null
+++ b/plat/mediatek/mt8195/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/mt8195/drivers/libdram/rules.mk b/plat/mediatek/mt8195/drivers/libdram/rules.mk
new file mode 100644
index 000000000..38f23c3dd
--- /dev/null
+++ b/plat/mediatek/mt8195/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/mt8195/include/platform_def.h b/plat/mediatek/mt8195/include/platform_def.h
index 187fd1eac..95e45a4d0 100644
--- a/plat/mediatek/mt8195/include/platform_def.h
+++ b/plat/mediatek/mt8195/include/platform_def.h
@@ -202,6 +202,8 @@
#define BL2_BASE (0x201000)
#define BL2_LIMIT (0x400000)
+#define BOOT_ARGUMENT_LOCATION (0x40000100) // Gotta match u-boot's arch/arm/include/asm/arch-mediatek/misc.h
+
#define MAX_IO_DEVICES U(3)
#define MAX_IO_HANDLES U(4)
#define MAX_IO_BLOCK_DEVICES 1
diff --git a/plat/mediatek/mt8195/platform.mk b/plat/mediatek/mt8195/platform.mk
index f62b8551d..f860ffd34 100644
--- a/plat/mediatek/mt8195/platform.mk
+++ b/plat/mediatek/mt8195/platform.mk
@@ -103,6 +103,7 @@ endif
endif
MODULES-BL2-y += ${MTK_PLAT}/common/drivers/blkdev
+MODULES-BL2-y += $(MTK_PLAT_SOC)/drivers/libdram
$(eval $(call add_define,PLAT_PARTITION_BLOCK_SIZE))
--
2.52.0