variables: create ad-hoc small .yaml files

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

Author: oharboe

flow/scripts/README.md

@@ -94,3 +94,17 @@ Load synthesis result and list modules that were kept in hierarchical synthesis:
     aes_cipher_top
     aes_key_expand_128
     %
+
+## Creating a .yaml file with specific variable values
+
+Print any variable in .yaml syntax. To create a .yaml file that
+contains value of variables, run:
+
+    make print-CORE_UTILIZATION print-PLACE_DENSITY > foo.yaml
+
+Outputs foo.yaml:
+
+    CORE_UTILIZATION: 55
+    PLACE_DENSITY: 0.30
+
+Useful in bazel-orfs flows or debugging configuration.

flow/scripts/variables.mk

@@ -213,7 +213,6 @@ vars:
 	$(UTILS_DIR)/generate-vars.sh $(OBJECTS_DIR)/vars
 
 .PHONY: print-%
-# Print any variable, for instance: make print-DIE_AREA
 print-%:
   # HERE BE DRAGONS!
   #
@@ -224,6 +223,6 @@ print-%:
   # We have to use $(file ...) because we want to be able
   # to print variables that contain newlines.
 	$(file >/tmp/print_tmp$$,$($*))
-	@echo -n "$* = "
+	@echo -n "$*: "
 	@cat /tmp/print_tmp$$
 	@rm /tmp/print_tmp$$