diff --git a/src/soc/ucb/riscv/Kconfig b/src/soc/ucb/riscv/Kconfig
index bd0945e908..e8a8d376ba 100644
--- a/src/soc/ucb/riscv/Kconfig
+++ b/src/soc/ucb/riscv/Kconfig
@@ -9,6 +9,7 @@ config SOC_UCB_RISCV
 	select ARCH_ROMSTAGE_RISCV
 	select ARCH_RAMSTAGE_RISCV
 	select RISCV_USE_ARCH_TIMER
+	select FLATTENED_DEVICE_TREE
 	bool
 	default n
 
diff --git a/src/soc/ucb/riscv/cbmem.c b/src/soc/ucb/riscv/cbmem.c
index 5c423a05bb..ff3f5db3fc 100644
--- a/src/soc/ucb/riscv/cbmem.c
+++ b/src/soc/ucb/riscv/cbmem.c
@@ -1,10 +1,18 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
+#include <assert.h>
 #include <cbmem.h>
 #include <symbols.h>
 #include <ramdetect.h>
+#include <commonlib/device_tree.h>
+#include <mcall.h>
 
 uintptr_t cbmem_top_chipset(void)
 {
-	return (uintptr_t)_dram + (probe_ramsize((uintptr_t)_dram, CONFIG_DRAM_SIZE_MB) * MiB);
+	uint64_t top;
+
+	top = fdt_get_memory_top((void *)HLS()->fdt);
+	ASSERT_MSG(top, "Failed reading memory range from FDT");
+
+	return MIN(top, (uint64_t)4 * GiB - 1);
 }