From 017f161a55b48807a73fc9dff0b69f081bf43ee3 Mon Sep 17 00:00:00 2001 From: Kim Phillips Date: Wed, 6 Nov 2013 05:15:24 +0100 Subject: [PATCH] ARM: 7877/1: use built-in byte swap function Enable the compiler intrinsic for byte swapping on arch ARM. This allows the compiler to detect and be able to optimize out byte swappings, and has a very modest benefit on vmlinux size (Linaro gcc 4.8): text data bss dec hex filename 2840310 123932 61960 3026202 2e2d1a vmlinux-lart #orig 2840152 123932 61960 3026044 2e2c7c vmlinux-lart #builtin-bswap 6473120 314840 5616016 12403976 bd4508 vmlinux-mxs #orig 6472586 314848 5616016 12403450 bd42fa vmlinux-mxs #builtin-bswap 7419872 318372 379556 8117800 7bde28 vmlinux-imx_v6_v7 #orig 7419170 318364 379556 8117090 7bdb62 vmlinux-imx_v6_v7 #builtin-bswap Signed-off-by: Kim Phillips Reviewed-by: Nicolas Pitre Acked-by: David Woodhouse Signed-off-by: Russell King --- arch/arm/Kconfig | 1 + arch/arm/boot/compressed/Makefile | 15 +++++++++---- arch/arm/kernel/armksyms.c | 4 ++++ arch/arm/lib/Makefile | 2 +- arch/arm/lib/bswapsdi2.S | 36 +++++++++++++++++++++++++++++++ 5 files changed, 53 insertions(+), 5 deletions(-) create mode 100644 arch/arm/lib/bswapsdi2.S diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index c1f1a7eee95..75597213c5b 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -6,6 +6,7 @@ config ARM select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAVE_CUSTOM_GPIO_H select ARCH_MIGHT_HAVE_PC_PARPORT + select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_CMPXCHG_LOCKREF select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_EXTABLE_SORT if MMU diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index e7190bb5998..4bb86d9a749 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -108,12 +108,12 @@ endif targets := vmlinux vmlinux.lds \ piggy.$(suffix_y) piggy.$(suffix_y).o \ - lib1funcs.o lib1funcs.S ashldi3.o ashldi3.S \ - font.o font.c head.o misc.o $(OBJS) + lib1funcs.o lib1funcs.S ashldi3.o ashldi3.S bswapsdi2.o \ + bswapsdi2.S font.o font.c head.o misc.o $(OBJS) # Make sure files are removed during clean extra-y += piggy.gzip piggy.lzo piggy.lzma piggy.xzkern piggy.lz4 \ - lib1funcs.S ashldi3.S $(libfdt) $(libfdt_hdrs) \ + lib1funcs.S ashldi3.S bswapsdi2.S $(libfdt) $(libfdt_hdrs) \ hyp-stub.S ifeq ($(CONFIG_FUNCTION_TRACER),y) @@ -156,6 +156,12 @@ ashldi3 = $(obj)/ashldi3.o $(obj)/ashldi3.S: $(srctree)/arch/$(SRCARCH)/lib/ashldi3.S $(call cmd,shipped) +# For __bswapsi2, __bswapdi2 +bswapsdi2 = $(obj)/bswapsdi2.o + +$(obj)/bswapsdi2.S: $(srctree)/arch/$(SRCARCH)/lib/bswapsdi2.S + $(call cmd,shipped) + # We need to prevent any GOTOFF relocs being used with references # to symbols in the .bss section since we cannot relocate them # independently from the rest at run time. This can be achieved by @@ -177,7 +183,8 @@ if [ $(words $(ZRELADDR)) -gt 1 -a "$(CONFIG_AUTO_ZRELADDR)" = "" ]; then \ fi $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \ - $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) $(ashldi3) FORCE + $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) $(ashldi3) \ + $(bswapsdi2) FORCE @$(check_for_multiple_zreladdr) $(call if_changed,ld) @$(check_for_bad_syms) diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c index 1f031ddd066..85e664b6a5f 100644 --- a/arch/arm/kernel/armksyms.c +++ b/arch/arm/kernel/armksyms.c @@ -35,6 +35,8 @@ extern void __ucmpdi2(void); extern void __udivsi3(void); extern void __umodsi3(void); extern void __do_div64(void); +extern void __bswapsi2(void); +extern void __bswapdi2(void); extern void __aeabi_idiv(void); extern void __aeabi_idivmod(void); @@ -114,6 +116,8 @@ EXPORT_SYMBOL(__ucmpdi2); EXPORT_SYMBOL(__udivsi3); EXPORT_SYMBOL(__umodsi3); EXPORT_SYMBOL(__do_div64); +EXPORT_SYMBOL(__bswapsi2); +EXPORT_SYMBOL(__bswapdi2); #ifdef CONFIG_AEABI EXPORT_SYMBOL(__aeabi_idiv); diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile index 47d7338561d..0573faab96a 100644 --- a/arch/arm/lib/Makefile +++ b/arch/arm/lib/Makefile @@ -13,7 +13,7 @@ lib-y := backtrace.o changebit.o csumipv6.o csumpartial.o \ ashldi3.o ashrdi3.o lshrdi3.o muldi3.o \ ucmpdi2.o lib1funcs.o div64.o \ io-readsb.o io-writesb.o io-readsl.o io-writesl.o \ - call_with_stack.o + call_with_stack.o bswapsdi2.o mmu-y := clear_user.o copy_page.o getuser.o putuser.o diff --git a/arch/arm/lib/bswapsdi2.S b/arch/arm/lib/bswapsdi2.S new file mode 100644 index 00000000000..9fcdd154eff --- /dev/null +++ b/arch/arm/lib/bswapsdi2.S @@ -0,0 +1,36 @@ +#include + +#if __LINUX_ARM_ARCH__ >= 6 +ENTRY(__bswapsi2) + rev r0, r0 + bx lr +ENDPROC(__bswapsi2) + +ENTRY(__bswapdi2) + rev r3, r0 + rev r0, r1 + mov r1, r3 + bx lr +ENDPROC(__bswapdi2) +#else +ENTRY(__bswapsi2) + eor r3, r0, r0, ror #16 + mov r3, r3, lsr #8 + bic r3, r3, #0xff00 + eor r0, r3, r0, ror #8 + mov pc, lr +ENDPROC(__bswapsi2) + +ENTRY(__bswapdi2) + mov ip, r1 + eor r3, ip, ip, ror #16 + eor r1, r0, r0, ror #16 + mov r1, r1, lsr #8 + mov r3, r3, lsr #8 + bic r3, r3, #0xff00 + bic r1, r1, #0xff00 + eor r1, r1, r0, ror #8 + eor r0, r3, ip, ror #8 + mov pc, lr +ENDPROC(__bswapdi2) +#endif -- 2.46.0