[PATCH v2] ARM: support XZ compressed kernels

[Imre Kaloz]

Wire up support for the XZ decompressor

Signed-off-by: Imre Kaloz <kaloz at openwrt.org>
---
Change since v1: added missing .gitignore modification

 arch/arm/Kconfig                        |    1 +
 arch/arm/boot/compressed/.gitignore     |    1 +
 arch/arm/boot/compressed/Makefile       |   11 +++++++++--
 arch/arm/boot/compressed/decompress.c   |    4 ++++
 arch/arm/boot/compressed/piggy.xzkern.S |    6 ++++++
 lib/xz/xz_dec_stream.c                  |    1 +
 6 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 arch/arm/boot/compressed/piggy.xzkern.S

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 9adc278..286873e 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -20,6 +20,7 @@ config ARM
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_LZMA
+	select HAVE_KERNEL_XZ
 	select HAVE_IRQ_WORK
 	select HAVE_PERF_EVENTS
 	select PERF_USE_VMALLOC
diff --git a/arch/arm/boot/compressed/.gitignore b/arch/arm/boot/compressed/.gitignore
index c602896..593a712 100644
--- a/arch/arm/boot/compressed/.gitignore
+++ b/arch/arm/boot/compressed/.gitignore
@@ -3,5 +3,6 @@ lib1funcs.S
 piggy.gzip
 piggy.lzo
 piggy.lzma
+piggy.xzkern
 vmlinux
 vmlinux.lds
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index 23aad07..e5db34e 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -82,13 +82,14 @@ SEDFLAGS	= s/TEXT_START/$(ZTEXTADDR)/;s/BSS_START/$(ZBSSADDR)/
 suffix_$(CONFIG_KERNEL_GZIP) = gzip
 suffix_$(CONFIG_KERNEL_LZO)  = lzo
 suffix_$(CONFIG_KERNEL_LZMA) = lzma
+suffix_$(CONFIG_KERNEL_XZ)   = xzkern
 
 targets       := vmlinux vmlinux.lds \
 		 piggy.$(suffix_y) piggy.$(suffix_y).o \
 		 font.o font.c head.o misc.o $(OBJS)
 
 # Make sure files are removed during clean
-extra-y       += piggy.gzip piggy.lzo piggy.lzma lib1funcs.S
+extra-y       += piggy.gzip piggy.lzo piggy.lzma piggy.xzkern lib1funcs.S ashldi3.S
 
 ifeq ($(CONFIG_FUNCTION_TRACER),y)
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
@@ -133,8 +134,14 @@ bad_syms=$$($(CROSS_COMPILE)nm $@ | sed -n 's/^.\{8\} [bc] \(.*\)/\1/p') && \
   ( echo "following symbols must have non local/private scope:" >&2; \
     echo "$$bad_syms" >&2; rm -f $@; false )
 
+# For __aeabi_llsl
+ashldi3 = $(obj)/ashldi3.o
+
+$(obj)/ashldi3.S: $(srctree)/arch/$(SRCARCH)/lib/ashldi3.S FORCE
+	$(call cmd,shipped)
+
 $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \
-	 	$(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE
+	 	$(addprefix $(obj)/, $(OBJS)) $(lib1funcs) $(ashldi3) FORCE
 	$(call if_changed,ld)
 	@$(check_for_bad_syms)
 
diff --git a/arch/arm/boot/compressed/decompress.c b/arch/arm/boot/compressed/decompress.c
index 07be5a2..0ecd8b4 100644
--- a/arch/arm/boot/compressed/decompress.c
+++ b/arch/arm/boot/compressed/decompress.c
@@ -44,6 +44,10 @@ extern void error(char *);
 #include "../../../../lib/decompress_unlzma.c"
 #endif
 
+#ifdef CONFIG_KERNEL_XZ
+#include "../../../../lib/decompress_unxz.c"
+#endif
+
 int do_decompress(u8 *input, int len, u8 *output, void (*error)(char *x))
 {
 	return decompress(input, len, NULL, NULL, output, NULL, error);
diff --git a/arch/arm/boot/compressed/piggy.xzkern.S b/arch/arm/boot/compressed/piggy.xzkern.S
new file mode 100644
index 0000000..5703f30
--- /dev/null
+++ b/arch/arm/boot/compressed/piggy.xzkern.S
@@ -0,0 +1,6 @@
+	.section .piggydata,#alloc
+	.globl	input_data
+input_data:
+	.incbin	"arch/arm/boot/compressed/piggy.xzkern"
+	.globl	input_data_end
+input_data_end:
diff --git a/lib/xz/xz_dec_stream.c b/lib/xz/xz_dec_stream.c
index ac809b1..9a60cc2 100644
--- a/lib/xz/xz_dec_stream.c
+++ b/lib/xz/xz_dec_stream.c
@@ -9,6 +9,7 @@
 
 #include "xz_private.h"
 #include "xz_stream.h"
+#include <linux/kernel.h>
 
 /* Hash used to validate the Index field */
 struct xz_dec_hash {
-- 
1.7.1