Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/scripts/gdb/linux/clk.py b/scripts/gdb/linux/clk.py
new file mode 100644
index 0000000..061aecf
--- /dev/null
+++ b/scripts/gdb/linux/clk.py
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (c) NXP 2019
+
+import gdb
+import sys
+
+from linux import utils, lists, constants
+
+clk_core_type = utils.CachedType("struct clk_core")
+
+
+def clk_core_for_each_child(hlist_head):
+    return lists.hlist_for_each_entry(hlist_head,
+            clk_core_type.get_type().pointer(), "child_node")
+
+
+class LxClkSummary(gdb.Command):
+    """Print clk tree summary
+
+Output is a subset of /sys/kernel/debug/clk/clk_summary
+
+No calls are made during printing, instead a (c) if printed after values which
+are cached and potentially out of date"""
+
+    def __init__(self):
+        super(LxClkSummary, self).__init__("lx-clk-summary", gdb.COMMAND_DATA)
+
+    def show_subtree(self, clk, level):
+        gdb.write("%*s%-*s %7d %8d %8d %11lu%s\n" % (
+                level * 3 + 1, "",
+                30 - level * 3,
+                clk['name'].string(),
+                clk['enable_count'],
+                clk['prepare_count'],
+                clk['protect_count'],
+                clk['rate'],
+                '(c)' if clk['flags'] & constants.LX_CLK_GET_RATE_NOCACHE else '   '))
+
+        for child in clk_core_for_each_child(clk['children']):
+            self.show_subtree(child, level + 1)
+
+    def invoke(self, arg, from_tty):
+        gdb.write("                                 enable  prepare  protect               \n")
+        gdb.write("   clock                          count    count    count        rate   \n")
+        gdb.write("------------------------------------------------------------------------\n")
+        for clk in clk_core_for_each_child(gdb.parse_and_eval("clk_root_list")):
+            self.show_subtree(clk, 0)
+        for clk in clk_core_for_each_child(gdb.parse_and_eval("clk_orphan_list")):
+            self.show_subtree(clk, 0)
+
+
+LxClkSummary()
+
+
+class LxClkCoreLookup(gdb.Function):
+    """Find struct clk_core by name"""
+
+    def __init__(self):
+        super(LxClkCoreLookup, self).__init__("lx_clk_core_lookup")
+
+    def lookup_hlist(self, hlist_head, name):
+        for child in clk_core_for_each_child(hlist_head):
+            if child['name'].string() == name:
+                return child
+            result = self.lookup_hlist(child['children'], name)
+            if result:
+                return result
+
+    def invoke(self, name):
+        name = name.string()
+        return (self.lookup_hlist(gdb.parse_and_eval("clk_root_list"), name) or
+                self.lookup_hlist(gdb.parse_and_eval("clk_orphan_list"), name))
+
+
+LxClkCoreLookup()