diff --git a/recipes-bsp/u-boot/u-boot-starfive_v2021.04.bb b/recipes-bsp/u-boot/u-boot-starfive_v2021.04.bb
index b558c34..289d297 100644
--- a/recipes-bsp/u-boot/u-boot-starfive_v2021.04.bb
+++ b/recipes-bsp/u-boot/u-boot-starfive_v2021.04.bb
@@ -43,3 +43,7 @@ do_deploy:append:visionfive() {
 COMPATIBLE_MACHINE = "(beaglev-starlight-jh7100|visionfive)"
 
 TOOLCHAIN = "gcc"
+
+# U-boot sets O=... which needs it to build outside of S
+B = "${WORKDIR}/build"
+