Add merging of labelled subnodes. This patch allows the following

syntax:

/ {
	child {
		label: subchild {
		};
	};
};

&label {
	prop = "value";
};

which will result in the following tree:

/ {
	child {
		label: subchild {
			prop = "value";
		};
	};
};

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

dtc-lexer.l

@@ -109,7 +109,7 @@ static int pop_input_file(void);
 			return DT_LITERAL;
 		}
 
-\&{LABEL}	{	/* label reference */
+<*>\&{LABEL}	{	/* label reference */
 			DPRINT("Ref: %s\n", yytext+1);
 			yylval.labelref = xstrdup(yytext+1);
 			return DT_REF;

dtc-parser.y

@@ -75,7 +75,6 @@ static unsigned long long eval_literal(const char *s, int base, int bits);
 %type <proplist> proplist
 
 %type <node> devicetree
-%type <node> devicetrees
 %type <node> nodedef
 %type <node> subnode
 %type <nodelist> subnodes
@@ -83,7 +82,7 @@ static unsigned long long eval_literal(const char *s, int base, int bits);
 %%
 
 sourcefile:
-	  DT_V1 ';' memreserves devicetrees
+	  DT_V1 ';' memreserves devicetree
 		{
 			the_boot_info = build_boot_info($3, $4,
 							guess_boot_cpuid($4));
@@ -120,22 +119,27 @@ addr:
 		}
 	  ;
 
-devicetrees:
-	  devicetree
-		{
-			$$ = $1;
-		}
-	| devicetrees devicetree
-		{
-			$$ = merge_nodes($1, $2);
-		}
-	;
-
 devicetree:
 	  '/' nodedef
 		{
 			$$ = name_node($2, "");
 		}
+	| devicetree '/' nodedef
+		{
+			$$ = merge_nodes($1, $3);
+		}
+	| devicetree DT_REF nodedef
+		{
+			struct node *target;
+
+			target = get_node_by_label($1, $2);
+			if (target)
+				merge_nodes(target, $3);
+			else
+				yyerror("label does not exist in "
+					" node redefinition");
+			$$ = $1;
+		}
 	;
 
 nodedef:

tests/nonexist-node-ref2.dts

@@ -0,0 +1,10 @@
+/dts-v1/;
+
+/ {
+	label: node {
+	};
+};
+
+/* Try to redefine a node using a non-existent label */
+&nosuchnode {
+};

tests/run_tests.sh

@@ -300,6 +300,8 @@ dtc_tests () {
     # Check merge/overlay functionality
     run_dtc_test -I dts -O dtb -o dtc_tree1_merge.test.dtb test_tree1_merge.dts
     tree1_tests dtc_tree1_merge.test.dtb test_tree1.dtb
+    run_dtc_test -I dts -O dtb -o dtc_tree1_merge_labelled.test.dtb test_tree1_merge_labelled.dts
+    tree1_tests dtc_tree1_merge_labelled.test.dtb test_tree1.dtb
     run_dtc_test -I dts -O dtb -o multilabel_merge.test.dtb multilabel_merge.dts
     run_test references multilabel.test.dtb
     run_test dtbs_equal_ordered multilabel.test.dtb multilabel_merge.test.dtb
@@ -312,6 +314,7 @@ dtc_tests () {
     check_tests minusone-phandle.dts explicit_phandles
     run_sh_test dtc-checkfails.sh phandle_references -- -I dts -O dtb nonexist-node-ref.dts
     run_sh_test dtc-checkfails.sh phandle_references -- -I dts -O dtb nonexist-label-ref.dts
+    run_sh_test dtc-fatal.sh -I dts -O dtb nonexist-node-ref2.dts
     check_tests bad-name-property.dts name_properties
 
     check_tests bad-ncells.dts address_cells_is_cell size_cells_is_cell interrupt_cells_is_cell

tests/test_tree1.dts

@@ -25,7 +25,7 @@
 		linux,phandle = <0x2000>;
 		prop-int = <123456789>;
 
-		subsubnode@0 {
+		ssn0: subsubnode@0 {
 			phandle = <0x2001>;
 			compatible = "subsubnode2", "subsubnode";
 			prop-int = <0726746425>;

tests/test_tree1_merge.dts

@@ -34,12 +34,10 @@
 		prop-int = [deadbeef];
 	};
 	subnode@2 {
-		subsubnode@0 {
+		ssn0: subsubnode@0 {
 			phandle = <0x2001>;
 			compatible = "subsubnode2", "subsubnode";
 			prop-int = <0726746425>;
 		};
 	};
 };
-
-

tests/test_tree1_merge_labelled.dts

@@ -0,0 +1,41 @@
+/dts-v1/;
+
+/memreserve/ 0xdeadbeef00000000 0x100000;
+/memreserve/ 123456789 010000;
+
+/ {
+	compatible = "test_tree1";
+	prop-int = <0xdeadbeef>;
+	prop-str = "hello world";
+
+	subnode@1 {
+		compatible = "subnode1";
+		prop-int = [deadbeef];
+
+		subsubnode {
+			compatible = "subsubnode1", "subsubnode";
+			prop-int = <0xdeadbeef>;
+		};
+
+		ss1 {
+		};
+	};
+
+	subnode@2 {
+		linux,phandle = <0x2000>;
+		prop-int = <123456789>;
+
+		ssn0: subsubnode@0 {
+			phandle = <0x2001>;
+			prop-int = <0xbad>;
+		};
+
+		ss2 {
+		};
+	};
+};
+
+&ssn0 {
+	compatible = "subsubnode2", "subsubnode";
+	prop-int = <0726746425>;
+};