From 78f23081e11821cc62e7f1ca56c53fbd165f01fa Mon Sep 17 00:00:00 2001
From: Jianqun Xu <jay.xu@rock-chips.com>
Date: Fri, 13 Mar 2020 10:43:45 +0800
Subject: [PATCH] scripts/dtc: Support delete unused nodes

Delete nodes in case of:
* node is null, without any property and children node
* node with 'status' property but not "okay" or "ok"

Change-Id: Ic7d2ba1cb60350c21fa6a46222c20870c74359d4
Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
---
 drivers/of/Kconfig   | 12 ++++++++++++
 scripts/Makefile.lib |  8 ++++++++
 scripts/dtc/checks.c | 23 +++++++++++++++++++++++
 3 files changed, 43 insertions(+)

diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 5e1315900562..6953974e9d96 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -12,6 +12,18 @@ menuconfig OF
 
 if OF
 
+config DTC_OMIT_DISABLED
+	bool "Fixup dtb by removing nodes with disabled status"
+	depends on DTC
+	help
+	  This option used for dtc to delete nodes with disabled status.
+
+config DTC_OMIT_EMPTY
+	bool "Fixup dtb by removing empty nodes"
+	depends on DTC
+	help
+	  This option used for dtc to delete empty nodes.
+
 config OF_UNITTEST
 	bool "Device Tree runtime unit tests"
 	depends on !SPARC
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index f7988649dc25..47a24a6863ad 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -249,6 +249,14 @@ ifeq ($(CONFIG_ANDROID),y)
 DTC_FLAGS += -@
 endif
 
+ifeq ($(CONFIG_DTC_OMIT_DISABLED),y)
+DTC_FLAGS += -Wnode_disabled
+endif
+
+ifeq ($(CONFIG_DTC_OMIT_EMPTY),y)
+DTC_FLAGS += -Wnode_empty
+endif
+
 # Disable noisy checks by default
 ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
 DTC_FLAGS += -Wno-unit_address_vs_reg \
diff --git a/scripts/dtc/checks.c b/scripts/dtc/checks.c
index a2cc1036c915..6302fa143331 100644
--- a/scripts/dtc/checks.c
+++ b/scripts/dtc/checks.c
@@ -623,6 +623,28 @@ static void fixup_path_references(struct check *c, struct dt_info *dti,
 }
 ERROR(path_references, fixup_path_references, NULL, &duplicate_node_names);
 
+static void fixup_node_disabled(struct check *c, struct dt_info *dti,
+				    struct node *node)
+{
+	struct property *prop = get_property(node, "status");
+
+	if (prop) {
+		const char *status = prop->val.val;
+
+		if (strcmp(status, "ok") && strcmp(status, "okay"))
+			omit_node_if_unused(node);
+	}
+}
+CHECK(node_disabled, fixup_node_disabled, NULL);
+
+static void fixup_node_empty(struct check *c, struct dt_info *dti,
+				    struct node *node)
+{
+	if (!node->proplist && !node->children)
+		omit_node_if_unused(node);
+}
+CHECK(node_empty, fixup_node_empty, NULL);
+
 static void fixup_omit_unused_nodes(struct check *c, struct dt_info *dti,
 				    struct node *node)
 {
@@ -1559,6 +1581,7 @@ static struct check *check_table[] = {
 
 	&explicit_phandles,
 	&phandle_references, &path_references,
+	&node_disabled, &node_empty,
 	&omit_unused_nodes,
 
 	&address_cells_is_cell, &size_cells_is_cell, &interrupt_cells_is_cell,