diff --git a/src/mainboard/emulation/qemu-power9/cbmem.c b/src/mainboard/emulation/qemu-power9/cbmem.c
new file mode 100644
index 0000000..c1c5e94
--- /dev/null
+++ b/src/mainboard/emulation/qemu-power9/cbmem.c
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <cbmem.h>
+
+void *cbmem_top_chipset(void)
+{
+	/* Top of cbmem is at lowest usable DRAM address below 4GiB. */
+	/* For now, last 1M of 4G */
+	void *ptr = (void *) (4ULL * GiB - 1 * MiB);
+	return ptr;
+}