diff --git a/firmware/rusefi.mk b/firmware/rusefi.mk
index e3b9d7bd55..8f4e8f8fe7 100644
--- a/firmware/rusefi.mk
+++ b/firmware/rusefi.mk
@@ -1,6 +1,7 @@
 
-ifeq ("$(wildcard $(RULESFILE))","")
-$(info $(RULESFILE) not found. Chibios: Invoking "git submodule update --init")
+CHIBIOS_FILE=$(CHIBIOS)/os/readme.txt
+ifeq ("$(wildcard $(CHIBIOS_FILE))","")
+$(info $(CHIBIOS_FILE) not found. Chibios: Invoking "git submodule update --init")
 $(shell git submodule update --init)
 $(info Invoked "git submodule update --init")
 # make is not happy about newly checked out module for some reason but next invocation would work
diff --git a/simulator/Makefile b/simulator/Makefile
index 977c5bbc03..31a933ab63 100644
--- a/simulator/Makefile
+++ b/simulator/Makefile
@@ -7,16 +7,15 @@
 # As of Sep 2019, this is known to compile on Linux
 # in my case I had to
 # sudo apt-get install gcc-multilib g++-multilib
-# 
+#
 # todo: automatically execute that command same as we automatically fetch submodules?
-# 
+#
 
 
 
 CHIBIOS = ../firmware/ChibiOS
 CHIBIOS_CONTRIB= ../firmware/ChibiOS-Contrib
 RULESPATH = $(CHIBIOS)/os/common/startup/SIMIA32/compilers/GCC
-RULESFILE = $(RULESPATH)/rules.mk
 
 PROJECT_CPU=simulator
 
@@ -85,7 +84,7 @@ endif
 
 # Linker extra options here.
 ifeq ($(USE_LDOPT),)
-  USE_LDOPT = 
+  USE_LDOPT =
 endif
 
 # Enable this if you want link time optimizations (LTO)
@@ -216,13 +215,13 @@ $(info OS is [${OS}])
 
 ifeq ($(OS),Windows_NT)
   # ChibiOS seem to require 32 bit compiler at least on Windows
-  # base 32-bit Cygwin is needed with mingw64 32-bit version 
+  # base 32-bit Cygwin is needed with mingw64 32-bit version
   # Cygwin64 would not debug if used with mingw64 32-bit version
   # 32 bit GDB available at http://www.equation.com/servlet/equation.cmd?fa=gdb
 
   TRGT = i686-w64-mingw32-
 else
-  TRGT = 
+  TRGT =
 endif
 
 CC   = $(TRGT)gcc