dm: Add support for handling old u-boot,dm- tags

Add a CONFIG option to deal with this automatically, printing a warning
when U-Boot starts up. This can be useful if the device tree comes from
another project.

We will maintain this through the 2023.07 release, providing 6 months
for people to notice.

Signed-off-by: Simon Glass <sjg@chromium.org>
Version 4:
Acked-by: Michal Simek <michal.simek@amd.com>

common/board_r.c

@@ -569,6 +569,13 @@ static int dm_announce(void)
 			printf("Warning: Unexpected devicetree source (not from a prior stage)");
 			printf("Warning: U-Boot may not function properly\n");
 		}
+		if (IS_ENABLED(CONFIG_OF_TAG_MIGRATE) &&
+		    (gd->flags & GD_FLG_OF_TAG_MIGRATE))
+			/*
+			 * U-Boot will silently fail to work after 2023.07 if
+			 * there are old tags present
+			 */
+			printf("Warning: Device tree includes old 'u-boot,dm-' tags: please fix by 2023.07!\n");
 	}
 
 	return 0;

drivers/core/ofnode.c

@@ -1330,6 +1330,18 @@ bool ofnode_pre_reloc(ofnode node)
 	    ofnode_read_bool(node, "u-boot,dm-tpl"))
 		return true;
 
+	if (IS_ENABLED(CONFIG_OF_TAG_MIGRATE)) {
+		/* detect and handle old tags */
+		if (ofnode_read_bool(node, "u-boot,dm-pre-reloc") ||
+		    ofnode_read_bool(node, "u-boot,dm-pre-proper") ||
+		    ofnode_read_bool(node, "u-boot,dm-spl") ||
+		    ofnode_read_bool(node, "u-boot,dm-tpl") ||
+		    ofnode_read_bool(node, "u-boot,dm-vpl")) {
+			gd->flags |= GD_FLG_OF_TAG_MIGRATE;
+			return true;
+		}
+	}
+
 	return false;
 #endif
 }

dts/Kconfig

@@ -342,6 +342,16 @@ config SPL_MULTI_DTB_FIT_USER_DEF_ADDR
 	   at compilation time. This is the address of this area. It must be
 	   aligned on 2-byte boundary.
 
+config OF_TAG_MIGRATE
+	bool "Ease migration from old device trees with u-boot,dm- tags"
+	default y
+	help
+	  U-Boot moved over to use new tags to mark device tree nodes which need
+	  to be processed in SPL, before relocation, etc. Enable this option to
+	  detect old tags and handle them.
+
+	  Note: This option will be removed after the 2023.07 release.
+
 config OF_SPL_REMOVE_PROPS
 	string "List of device tree properties to drop for SPL"
 	depends on SPL_OF_CONTROL

include/asm-generic/global_data.h

@@ -650,6 +650,10 @@ enum gd_flags {
 	 * @GD_FLG_FDT_CHANGED: Device tree change has been detected by tests
 	 */
 	GD_FLG_FDT_CHANGED = 0x100000,
+	/**
+	 * @GD_FLG_OF_TAG_MIGRATE: Device tree has old u-boot,dm- tags
+	 */
+	GD_FLG_OF_TAG_MIGRATE = 0x200000,
 };
 
 #endif /* __ASSEMBLY__ */

scripts/Makefile.lib

@@ -585,24 +585,35 @@ cmd_mkimage = $(objtree)/tools/mkimage $(MKIMAGEFLAGS_$(@F)) -d $< $@ \
 # ---------------------------------------------------------------------------
 # Pass the original device tree file through fdtgrep twice. The first pass
 # removes any unwanted nodes (i.e. those which don't have the
-# 'u-boot,dm-pre-reloc' property and thus are not needed by SPL. The second
+# 'bootph-all' property and thus are not needed by SPL. The second
 # pass removes various unused properties from the remaining nodes.
 # The output is typically a much smaller device tree file.
+
+ifdef CONFIG_OF_TAG_MIGRATE
+# Support the old tags for a migration period
+migrate_tpl := -b u-boot,dm-pre-reloc -b u-boot,dm-tpl
+migrate_vpl := -b u-boot,dm-pre-reloc -b u-boot,dm-vpl
+migrate_spl := -b u-boot,dm-pre-reloc -b u-boot,dm-spl
+migrate_all := -P u-boot,dm-pre-reloc \
+	-P u-boot,dm-spl -P u-boot,dm-tpl -P u-boot,dm-vpl
+endif
+
 ifeq ($(CONFIG_VPL_BUILD),y)
-fdtgrep_props := -b u-boot,dm-pre-reloc -b u-boot,dm-vpl
+fdtgrep_props := -b bootph-all -b bootph-verify $(migrate_vpl)
 else
 ifeq ($(CONFIG_TPL_BUILD),y)
-fdtgrep_props := -b u-boot,dm-pre-reloc -b u-boot,dm-tpl
+fdtgrep_props := -b bootph-all -b bootph-pre-sram $(migrate_tpl)
 else
-fdtgrep_props := -b u-boot,dm-pre-reloc -b u-boot,dm-spl
+fdtgrep_props := -b bootph-all -b bootph-pre-ram $(migrate_spl)
 endif
 endif
 quiet_cmd_fdtgrep = FDTGREP $@
       cmd_fdtgrep = $(objtree)/tools/fdtgrep $(fdtgrep_props) -RT $< \
 		-n /chosen -n /config -O dtb | \
 	$(objtree)/tools/fdtgrep -r -O dtb - -o $@ \
-		-P u-boot,dm-pre-reloc -P u-boot,dm-spl -P u-boot,dm-tpl \
+		-P bootph-all -P bootph-pre-ram -P bootph-pre-sram \
-		 -P u-boot,dm-vpl \
+		-P bootph-verify \
+		$(migrate_all) \
 		$(addprefix -P ,$(subst $\",,$(CONFIG_OF_SPL_REMOVE_PROPS)))
 
 # fdt_rm_props