to rebuild the tool binaries here from source if needed:

mkkrnlimg: make - in rk-tools
rkcrc: cc -o rkcrc rkcrc.c - in rkutils
resource_tool: make - in u-boot-rockchip/tools/resource_tool

git repos:

origin	https://github.com/goodybag/rk-tools.git (fetch)
On branch master

origin	https://github.com/T-Firefly/rkutils.git (fetch)
On branch master

origin	https://github.com/linux-rockchip/u-boot-rockchip.git (fetch)
On branch u-boot-rk3288

patch for u-boot-rockchip.git:

diff --git a/tools/resource_tool/Makefile b/tools/resource_tool/Makefile
index 45b54f8b85..19978af721 100644
--- a/tools/resource_tool/Makefile
+++ b/tools/resource_tool/Makefile
@@ -6,7 +6,8 @@ HEADERS = resource_tool.h common.h
 SOURCES = resource_tool.c common.c
 OBJS    = $(SOURCES:.c=.o)
 
-CFLAGS  = -fshort-wchar -m32 -ffunction-sections -Os
+#CFLAGS  = -fshort-wchar -m32 -ffunction-sections -Os
+CFLAGS  = -fshort-wchar -ffunction-sections -Os
 LDFLAGS = -Wl,--gc-sections -static
 
 SOURCES += tests.c
