[PATCH v2 1/3] xz: add arch-specific tuning for alpha

[Matt Turner <mattst88@gmail.com>]

Alpha has fixed-length, 4-byte-aligned instructions and no XZ BCJ
filter, so it wants the same LZMA2 settings as the other 4-byte-aligned
targets. Without an entry it hits the default case, which warns

  scripts/xz_wrap.sh: Arch-specific tuning is missing for 'alpha'

and conservatively assumes 2-byte alignment. Alpha gains HAVE_KERNEL_XZ
later in this series; the correct alignment also shrinks a UP1500
kernel's XZ image from 6469320 to 6448840 bytes.

Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Reviewed-by: Lasse Collin <lasse.collin@tukaani.org>
---
 scripts/xz_wrap.sh | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/scripts/xz_wrap.sh b/scripts/xz_wrap.sh
index f19369687030..5af0d9045cbc 100755
--- a/scripts/xz_wrap.sh
+++ b/scripts/xz_wrap.sh
@@ -10,6 +10,7 @@
 # XZ-compressed kernel isn't currently supported on every listed arch.
 #
 #   Arch        Align   Notes
+#   alpha         4
 #   arm          2/4    ARM and ARM-Thumb2
 #   arm64         4
 #   csky          2
@@ -44,6 +45,10 @@ BCJ=
 # Set the BCJ filter if one is available.
 # It must match the #ifdef usage in lib/decompress_unxz.c.
 case $SRCARCH in
+	alpha)
+		ALIGN=4
+		;;
+
 	arm)
 		if is_enabled CONFIG_THUMB2_KERNEL; then
 			ALIGN=2

-- 
2.55.0