Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/scripts/atomic/atomic-tbl.sh b/scripts/atomic/atomic-tbl.sh
new file mode 100755
index 0000000..81d5c32
--- /dev/null
+++ b/scripts/atomic/atomic-tbl.sh
@@ -0,0 +1,186 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# helpers for dealing with atomics.tbl
+
+#meta_in(meta, match)
+meta_in()
+{
+	case "$1" in
+	[$2]) return 0;;
+	esac
+
+	return 1
+}
+
+#meta_has_ret(meta)
+meta_has_ret()
+{
+	meta_in "$1" "bBiIfFlR"
+}
+
+#meta_has_acquire(meta)
+meta_has_acquire()
+{
+	meta_in "$1" "BFIlR"
+}
+
+#meta_has_release(meta)
+meta_has_release()
+{
+	meta_in "$1" "BFIRs"
+}
+
+#meta_has_relaxed(meta)
+meta_has_relaxed()
+{
+	meta_in "$1" "BFIR"
+}
+
+#find_fallback_template(pfx, name, sfx, order)
+find_fallback_template()
+{
+	local pfx="$1"; shift
+	local name="$1"; shift
+	local sfx="$1"; shift
+	local order="$1"; shift
+
+	local base=""
+	local file=""
+
+	# We may have fallbacks for a specific case (e.g. read_acquire()), or
+	# an entire class, e.g. *inc*().
+	#
+	# Start at the most specific, and fall back to the most general. Once
+	# we find a specific fallback, don't bother looking for more.
+	for base in "${pfx}${name}${sfx}${order}" "${name}"; do
+		file="${ATOMICDIR}/fallbacks/${base}"
+
+		if [ -f "${file}" ]; then
+			printf "${file}"
+			break
+		fi
+	done
+}
+
+#gen_ret_type(meta, int)
+gen_ret_type() {
+	local meta="$1"; shift
+	local int="$1"; shift
+
+	case "${meta}" in
+	[sv]) printf "void";;
+	[bB]) printf "bool";;
+	[aiIfFlR]) printf "${int}";;
+	esac
+}
+
+#gen_ret_stmt(meta)
+gen_ret_stmt()
+{
+	if meta_has_ret "${meta}"; then
+		printf "return ";
+	fi
+}
+
+# gen_param_name(arg)
+gen_param_name()
+{
+	# strip off the leading 'c' for 'cv'
+	local name="${1#c}"
+	printf "${name#*:}"
+}
+
+# gen_param_type(arg, int, atomic)
+gen_param_type()
+{
+	local type="${1%%:*}"; shift
+	local int="$1"; shift
+	local atomic="$1"; shift
+
+	case "${type}" in
+	i) type="${int} ";;
+	p) type="${int} *";;
+	v) type="${atomic}_t *";;
+	cv) type="const ${atomic}_t *";;
+	esac
+
+	printf "${type}"
+}
+
+#gen_param(arg, int, atomic)
+gen_param()
+{
+	local arg="$1"; shift
+	local int="$1"; shift
+	local atomic="$1"; shift
+	local name="$(gen_param_name "${arg}")"
+	local type="$(gen_param_type "${arg}" "${int}" "${atomic}")"
+
+	printf "${type}${name}"
+}
+
+#gen_params(int, atomic, arg...)
+gen_params()
+{
+	local int="$1"; shift
+	local atomic="$1"; shift
+
+	while [ "$#" -gt 0 ]; do
+		gen_param "$1" "${int}" "${atomic}"
+		[ "$#" -gt 1 ] && printf ", "
+		shift;
+	done
+}
+
+#gen_args(arg...)
+gen_args()
+{
+	while [ "$#" -gt 0 ]; do
+		printf "$(gen_param_name "$1")"
+		[ "$#" -gt 1 ] && printf ", "
+		shift;
+	done
+}
+
+#gen_proto_order_variants(meta, pfx, name, sfx, ...)
+gen_proto_order_variants()
+{
+	local meta="$1"; shift
+	local pfx="$1"; shift
+	local name="$1"; shift
+	local sfx="$1"; shift
+
+	gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "" "$@"
+
+	if meta_has_acquire "${meta}"; then
+		gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "_acquire" "$@"
+	fi
+	if meta_has_release "${meta}"; then
+		gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "_release" "$@"
+	fi
+	if meta_has_relaxed "${meta}"; then
+		gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "_relaxed" "$@"
+	fi
+}
+
+#gen_proto_variants(meta, name, ...)
+gen_proto_variants()
+{
+	local meta="$1"; shift
+	local name="$1"; shift
+	local pfx=""
+	local sfx=""
+
+	meta_in "${meta}" "fF" && pfx="fetch_"
+	meta_in "${meta}" "R" && sfx="_return"
+
+	gen_proto_order_variants "${meta}" "${pfx}" "${name}" "${sfx}" "$@"
+}
+
+#gen_proto(meta, ...)
+gen_proto() {
+	local meta="$1"; shift
+	for m in $(echo "${meta}" | grep -o .); do
+		gen_proto_variants "${m}" "$@"
+	done
+}