dm: core: Move "/chosen" and "/firmware" node scan

Use the new function dm_scan_fdt_ofnode_path() to scan all the nodes
which aren't devices themselves but may contain some:
- "/chosen"
- "/clocks"
- "/firmware"

The patch removes the strcmp call in recursive function dm_scan_fdt_live()
and also corrects a conflict with the 2 applied patches in
the commit 1712ca2192 ("dm: core: Scan /firmware node by default")
and in the commit 747558d014 ("dm: fdt: scan for devices under
/firmware too"): the subnodes of "/firmware" (optee for example)
are bound 2 times.

For example the dm tree command result on STM32MP1 is:

STM32MP> dm tree
 Class     Index  Probed  Driver                Name
 -----------------------------------------------------------
 root          0  [ + ]   root_driver           root_driver
 firmware      0  [   ]   psci                  |-- psci
 sysreset      0  [   ]   psci-sysreset         |   `-- psci-sysreset
 simple_bus    0  [ + ]   generic_simple_bus    |-- soc
...
 tee           0  [ + ]   optee                 |-- optee
...
 tee           1  [   ]   optee                 `-- optee

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/core/root.c

@@ -203,15 +203,6 @@ static int dm_scan_fdt_live(struct udevice *parent,
 	int ret = 0, err;
 
 	for (np = node_parent->child; np; np = np->sibling) {
-		/* "chosen" node isn't a device itself but may contain some: */
-		if (!strcmp(np->name, "chosen")) {
-			pr_debug("parsing subnodes of \"chosen\"\n");
-
-			err = dm_scan_fdt_live(parent, np, pre_reloc_only);
-			if (err && !ret)
-				ret = err;
-			continue;
-		}
 
 		if (!of_device_is_available(np)) {
 			pr_debug("   - ignoring disabled device\n");
@@ -256,21 +247,6 @@ static int dm_scan_fdt_node(struct udevice *parent, const void *blob,
 	     offset = fdt_next_subnode(blob, offset)) {
 		const char *node_name = fdt_get_name(blob, offset, NULL);
 
-		/*
-		 * The "chosen" and "firmware" nodes aren't devices
-		 * themselves but may contain some:
-		 */
-		if (!strcmp(node_name, "chosen") ||
-		    !strcmp(node_name, "firmware")) {
-			pr_debug("parsing subnodes of \"%s\"\n", node_name);
-
-			err = dm_scan_fdt_node(parent, blob, offset,
-					       pre_reloc_only);
-			if (err && !ret)
-				ret = err;
-			continue;
-		}
-
 		if (!fdtdec_get_is_enabled(blob, offset)) {
 			pr_debug("   - ignoring disabled device\n");
 			continue;
@@ -315,7 +291,8 @@ int dm_scan_fdt(const void *blob, bool pre_reloc_only)
 	return dm_scan_fdt_node(gd->dm_root, blob, 0, pre_reloc_only);
 }
 
-static int dm_scan_fdt_ofnode_path(const char *path, bool pre_reloc_only)
+static int dm_scan_fdt_ofnode_path(const void *blob, const char *path,
+				   bool pre_reloc_only)
 {
 	ofnode node;
 
@@ -327,13 +304,18 @@ static int dm_scan_fdt_ofnode_path(const char *path, bool pre_reloc_only)
 	if (of_live_active())
 		return dm_scan_fdt_live(gd->dm_root, node.np, pre_reloc_only);
 #endif
-	return dm_scan_fdt_node(gd->dm_root, gd->fdt_blob, node.of_offset,
+	return dm_scan_fdt_node(gd->dm_root, blob, node.of_offset,
 				pre_reloc_only);
 }
 
 int dm_extended_scan_fdt(const void *blob, bool pre_reloc_only)
 {
-	int ret;
+	int ret, i;
+	const char * const nodes[] = {
+		"/chosen",
+		"/clocks",
+		"/firmware"
+	};
 
 	ret = dm_scan_fdt(blob, pre_reloc_only);
 	if (ret) {
@@ -341,16 +323,16 @@ int dm_extended_scan_fdt(const void *blob, bool pre_reloc_only)
 		return ret;
 	}
 
-	ret = dm_scan_fdt_ofnode_path("/clocks", pre_reloc_only);
+	/* Some nodes aren't devices themselves but may contain some */
-	if (ret) {
+	for (i = 0; i < ARRAY_SIZE(nodes); i++) {
-		debug("scan for /clocks failed: %d\n", ret);
+		ret = dm_scan_fdt_ofnode_path(blob, nodes[i], pre_reloc_only);
-		return ret;
+		if (ret) {
+			debug("dm_scan_fdt() scan for %s failed: %d\n",
+			      nodes[i], ret);
+			return ret;
+		}
 	}
 
-	ret = dm_scan_fdt_ofnode_path("/firmware", pre_reloc_only);
-	if (ret)
-		debug("scan for /firmware failed: %d\n", ret);
-
 	return ret;
 }
 #endif

test/dm/test-fdt.c

@@ -255,7 +255,7 @@ static int dm_test_fdt(struct unit_test_state *uts)
 	int ret;
 	int i;
 
-	ret = dm_scan_fdt(gd->fdt_blob, false);
+	ret = dm_extended_scan_fdt(gd->fdt_blob, false);
 	ut_assert(!ret);
 
 	ret = uclass_get(UCLASS_TEST_FDT, &uc);