--- /dev/null
+################################################################################
+# Linux RTAI extensions
+#
+# Patch the linux kernel with RTAI extension
+################################################################################
+
+LINUX_EXTENSIONS += rtai
+
+ifeq ($(KERNEL_ARCH),i386)
+RTAI_ARCH = x86
+else ifeq ($(KERNEL_ARCH),x86_64)
+RTAI_ARCH = x86
+else ifeq ($(KERNEL_ARCH),powerpc)
+RTAI_ARCH = ppc
+else
+RTAI_ARCH = $(KERNEL_ARCH)
+endif
+
+# Prepare kernel patch
+define RTAI_PREPARE_KERNEL
+ kver=`$(MAKE) $(LINUX_MAKE_FLAGS) -C $(LINUX_DIR) --no-print-directory -s kernelversion` ; \
+ if test -f $(RTAI_DIR)/base/arch/$(RTAI_ARCH)/patches/hal-linux-$${kver}-*patch ; then \
+ $(APPLY_PATCHES) $(LINUX_DIR) \
+ $(RTAI_DIR)/base/arch/$(RTAI_ARCH)/patches/ \
+ hal-linux-$${kver}-*patch ; \
+ else \
+ echo "No RTAI patch for your kernel version" ; \
+ exit 1 ; \
+ fi
+endef