1 files changed, 38 insertions, 0 deletions
diff --git a/roms/u-boot/arch/riscv/cpu/generic/dram.c b/roms/u-boot/arch/riscv/cpu/generic/dram.c
new file mode 100644
index 000000000..1fdc7837b
--- /dev/null
+++ b/roms/u-boot/arch/riscv/cpu/generic/dram.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
+ */
+
+#include <common.h>
+#include <fdtdec.h>
+#include <init.h>
+#include <asm/global_data.h>
+#include <linux/sizes.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int dram_init(void)
+{
+	return fdtdec_setup_mem_size_base();
+}
+
+int dram_init_banksize(void)
+{
+	return fdtdec_setup_memory_banksize();
+}
+
+ulong board_get_usable_ram_top(ulong total_size)
+{
+	/*
+	 * Ensure that we run from first 4GB so that all
+	 * addresses used by U-Boot are 32bit addresses.
+	 *
+	 * This in-turn ensures that 32bit DMA capable
+	 * devices work fine because DMA mapping APIs will
+	 * provide 32bit DMA addresses only.
+	 */
+	if (gd->ram_top >= SZ_4G)
+		return SZ_4G - 1;
+
+	return gd->ram_top;
+}