diff --git a/configs/sandbox_flattree_defconfig b/configs/sandbox_flattree_defconfig
index 46e9dff..dd93167 100644
--- a/configs/sandbox_flattree_defconfig
+++ b/configs/sandbox_flattree_defconfig
@@ -136,6 +136,7 @@
 CONFIG_PCI=y
 CONFIG_DM_PCI=y
 CONFIG_DM_PCI_COMPAT=y
+CONFIG_PCI_REGION_MULTI_ENTRY=y
 CONFIG_PCI_SANDBOX=y
 CONFIG_PHY=y
 CONFIG_PHY_SANDBOX=y