dm: MIGRATION: Add migration plan for CONFIG_DM

For many sub-systems we already require the driver model to be used. Yet
there is still a handful of boards that do not have CONFIG_DM enabled.

We should make CONFIG_DM compulsory with release v2020.01

Conversion dates for CONFIG_DM_SPL and CONFIG_DM_TPL are yet to be defined.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/Makefile b/Makefile
index 57d0700..ffc2c4b 100644
--- a/Makefile
+++ b/Makefile
@@ -940,6 +940,14 @@
 endif
 endif
 endif
+ifneq ($(CONFIG_DM),y)
+	@echo >&2 "===================== WARNING ======================"
+	@echo >&2 "This board does not use CONFIG_DM. CONFIG_DM will be"
+	@echo >&2 "compulsory starting with the v2020.01 release."
+	@echo >&2 "Failure to update may result in board removal."
+	@echo >&2 "See doc/driver-model/migration.rst for more info."
+	@echo >&2 "===================================================="
+endif
 ifeq ($(CONFIG_MMC),y)
 ifneq ($(CONFIG_DM_MMC)$(CONFIG_OF_CONTROL)$(CONFIG_BLK),yyy)
 	@echo >&2 "===================== WARNING ======================"
diff --git a/doc/driver-model/migration.rst b/doc/driver-model/migration.rst
index fd499fb..d1fc0e6 100644
--- a/doc/driver-model/migration.rst
+++ b/doc/driver-model/migration.rst
@@ -7,6 +7,16 @@
 2014. This file describes the schedule for deprecation of pre-driver-model
 features.
 
+CONFIG_DM
+---------
+
+* Status: In progress
+* Deadline: 2020.01
+
+Starting with the 2010.01 release CONFIG_DM will be enabled for all boards.
+This does not concern CONFIG_DM_SPL and CONFIG_DM_TPL. The conversion date for
+these configuration items still needs to be defined.
+
 CONFIG_DM_MMC
 -------------