build: add a config option for enabling a testing version of the target kernel

If the target supports a newer kernel version that is not used by default
yet, it can be enabled with this option

Signed-off-by: Felix Fietkau <nbd@nbd.name>

2 files changed, 13 insertions, 5 deletions

diff --git a/scripts/metadata.pm b/scripts/metadata.pm
index a338b8caad..d088332152 100644
--- a/scripts/metadata.pm
+++ b/scripts/metadata.pm
@@ -131,6 +131,7 @@ sub parse_target_metadata($) {
 		/^Target-Optimization:\s*(.+)\s*$/ and $target->{cflags} = $1;
 		/^CPU-Type:\s*(.+)\s*$/ and $target->{cputype} = $1;
 		/^Linux-Version:\s*(.+)\s*$/ and $target->{version} = $1;
+		/^Linux-Testing-Version:\s*(.+)\s*$/ and $target->{testing_version} = $1;
 		/^Linux-Release:\s*(.+)\s*$/ and $target->{release} = $1;
 		/^Linux-Kernel-Arch:\s*(.+)\s*$/ and $target->{karch} = $1;
 		/^Default-Subtarget:\s*(.+)\s*$/ and $target->{def_subtarget} = $1;
diff --git a/scripts/target-metadata.pl b/scripts/target-metadata.pl
index 123958799f..d183e943f6 100755
--- a/scripts/target-metadata.pl
+++ b/scripts/target-metadata.pl
@@ -42,6 +42,7 @@ sub target_config_features(@) {
 		/^virtio$/ and $ret .= "\tselect VIRTIO_SUPPORT\n";
 		/^rootfs-part$/ and $ret .= "\tselect USES_ROOTFS_PART\n";
 		/^boot-part$/ and $ret .= "\tselect USES_BOOT_PART\n";
+		/^testing-kernel$/ and $ret .= "\tselect HAS_TESTING_KERNEL\n";
 	}
 	return $ret;
 }
@@ -83,11 +84,14 @@ sub print_target($) {
 	}
 
 	my $v = kver($target->{version});
+	my $tv = kver($target->{testing_version});
+	$tv or $tv = $v;
 	if (@{$target->{subtargets}} == 0) {
 	$confstr = <<EOF;
 config TARGET_$target->{conf}
 	bool "$target->{name}"
-	select LINUX_$v
+	select LINUX_$v if !TESTING_KERNEL
+	select LINUX_$tv if TESTING_KERNEL
 EOF
 	}
 	else {
@@ -387,15 +391,18 @@ EOF
 
 	my %kver;
 	foreach my $target (@target) {
-		my $v = kver($target->{version});
-		next if $kver{$v};
-		$kver{$v} = 1;
-		print <<EOF;
+		foreach my $tv ($target->{version}, $target->{testing_version}) {
+			next unless $tv;
+			my $v = kver($tv);
+			next if $kver{$v};
+			$kver{$v} = 1;
+			print <<EOF;
 
 config LINUX_$v
 	bool
 
 EOF
+		}
 	}
 	foreach my $def (sort keys %defaults) {
 		print <<EOF;