Platform/cisco-8000 module for sonic-buildimage (sonic-net#8172)

Why I did it
Update Makefile, so it does the following:
For a given platform, verify if platform/checkout/.ini exists and hence run the platform/checkout/template.j2. This allows platform code to be checked out during the 'make configure' stage.

How I did it
git clone git@github.com:Azure/sonic-buildimage.git
mkdir platform/cisco-8000

make init
make configure PLATFORM=cisco-8000
make all

.gitignore

@@ -74,6 +74,7 @@ platform/broadcom/sonic-platform-modules-dell/s6100/modules/dell_s6100_lpc.c
 platform/broadcom/sonic-platform-modules-dell/z9100/modules/dell_ich.c
 platform/broadcom/sonic-platform-modules-dell/z9100/modules/dell_mailbox.c
 platform/broadcom/sonic-platform-modules-dell/z9264f/sonic_platform/ipmihelper.py
+platform/cisco-8000
 
 # buildinfo
 files/build/buildinfo

Makefile

@@ -5,6 +5,27 @@ NOSTRETCH ?= 0
 NOBUSTER ?= 0
 NOBULLSEYE ?= 1
 
+ifeq ($(NOJESSIE),0)
+BUILD_JESSIE=1
+endif
+
+ifeq ($(NOSTRETCH),0)
+BUILD_STRETCH=1
+endif
+
+ifeq ($(NOBUSTER),0)
+BUILD_BUSTER=1
+endif
+
+ifeq ($(NOBULLSEYE),0)
+BUILD_BULLSEYE=1
+endif
+
+PLATFORM_PATH := platform/$(if $(PLATFORM),$(PLATFORM),$(CONFIGURED_PLATFORM))
+PLATFORM_CHECKOUT := platform/checkout
+PLATFORM_CHECKOUT_FILE := $(PLATFORM_CHECKOUT)/$(PLATFORM).ini
+PLATFORM_CHECKOUT_CMD := $(shell if [ -f $(PLATFORM_CHECKOUT_FILE) ]; then PLATFORM_PATH=$(PLATFORM_PATH) j2 $(PLATFORM_CHECKOUT)/template.j2 $(PLATFORM_CHECKOUT_FILE); fi)
+
 %::
 	@echo "+++ --- Making $@ --- +++"
 ifeq ($(NOJESSIE), 0)
@@ -42,20 +63,28 @@ init:
 	@echo "+++ Making $@ +++"
 	make -f Makefile.work $@
 
-clean configure reset showtag sonic-slave-build sonic-slave-bash :
+#
+# Function to invoke target $@ in Makefile.work with proper BLDENV
+#
+define make_work
 	@echo "+++ Making $@ +++"
-ifeq ($(NOJESSIE), 0)
-	make -f Makefile.work $@
-endif
-ifeq ($(NOSTRETCH), 0)
-	BLDENV=stretch make -f Makefile.work $@
-endif
-ifeq ($(NOBUSTER), 0)
-	BLDENV=buster make -f Makefile.work $@
-endif
-ifeq ($(NOBULLSEYE), 0)
-	BLDENV=bullseye make -f Makefile.work $@
-endif
+	$(if $(BUILD_JESSIE),make -f Makefile.work $@,)
+	$(if $(BUILD_STRETCH),BLDENV=stretch make -f Makefile.work $@,)
+	$(if $(BUILD_BUSTER),BLDENV=buster make -f Makefile.work $@,)
+	$(if $(BUILD_BULLSEYE),BLDENV=bullseye make -f Makefile.work $@,)
+endef
+
+.PHONY: $(PLATFORM_PATH)
+
+$(PLATFORM_PATH):
+	@echo "+++ Cheking $@ +++"
+	$(PLATFORM_CHECKOUT_CMD)
+
+configure : $(PLATFORM_PATH)
+	$(call make_work, $@)
+
+clean reset showtag sonic-slave-build sonic-slave-bash :
+	$(call make_work, $@)
 
 # Freeze the versions, see more detail options: scripts/versions_manager.py freeze -h
 freeze:

platform/checkout/cisco-8000.ini

@@ -0,0 +1,3 @@
+[module]
+repo=git@github.com:Cisco-8000-sonic/platform-cisco-8000.git
+ref=v0.1

platform/checkout/template.j2

@@ -0,0 +1,11 @@
+{% set path = env('PLATFORM_PATH') %}
+if [ ! -d {{ path }} ]; then git clone {{ module.repo }} {{ path }}; fi;
+if [ -d {{ path }}/.git ]; then cd {{ path }} &&
+
+{% if module.ref is defined %}
+git checkout {{ module.ref }} && git submodule update --init --recursive;
+{% else %}
+git submodule update --init --recursive;
+{% endif %}
+
+else echo "{{ path }}/.git not found"; exit 1; fi