From mboxrd@z Thu Jan 1 00:00:00 1970 From: max@stro.at (maximilian attems) Date: Tue, 17 May 2011 18:17:10 +0200 Subject: [PATCH] [klibc] arm: use bx on thumb2 v3 Message-ID: <1305649031-15622-1-git-send-email-max@stro.at> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Use klibc way to define a system dependent preprocessor definition: disabled by default and enabled for newer arm. Based on a patch by vorlon that got tested on his beagleboard, should be functional equivalent. Fixes: https://bugs.launchpad.net/ubuntu/+source/klibc/+bug/527720 Cc: Steve Langasek Cc: Kirill A. Shutemov Cc: Michael Tokarev Signed-off-by: maximilian attems --- usr/include/arch/arm/klibc/archconfig.h | 6 +++++- usr/include/arch/arm/klibc/asmmacros.h | 6 ++++++ usr/include/klibc/sysconfig.h | 9 +++++++++ usr/klibc/arch/arm/setjmp.S | 10 ++++++---- usr/klibc/arch/arm/vfork.S | 5 +++-- 5 files changed, 29 insertions(+), 7 deletions(-) diff --git a/usr/include/arch/arm/klibc/archconfig.h b/usr/include/arch/arm/klibc/archconfig.h index e34bdb7..36e9ab5 100644 --- a/usr/include/arch/arm/klibc/archconfig.h +++ b/usr/include/arch/arm/klibc/archconfig.h @@ -9,6 +9,10 @@ #ifndef _KLIBC_ARCHCONFIG_H #define _KLIBC_ARCHCONFIG_H -/* All defaults */ +/* newer arm arch support bx instruction */ +#if (!defined(__ARM_ARCH_2__) && !defined(__ARM_ARCH_3__) \ + && !defined(__ARM_ARCH_3M__) && !defined(__ARM_ARCH_4__)) +# define _KLIBC_ARM_USE_BX 1 +#endif #endif /* _KLIBC_ARCHCONFIG_H */ diff --git a/usr/include/arch/arm/klibc/asmmacros.h b/usr/include/arch/arm/klibc/asmmacros.h index 8a21c94..45bea0e 100644 --- a/usr/include/arch/arm/klibc/asmmacros.h +++ b/usr/include/arch/arm/klibc/asmmacros.h @@ -27,4 +27,10 @@ (((x) & ~0xf000000f) == 0) || \ (((x) & ~0xc000003f) == 0)) +#if _KLIBC_ARM_USE_BX +# define BX(x) bx ##x +#else +# define BX(x) mov pc, ##x +#endif + #endif /* _KLIBC_ASMMACROS_H */ diff --git a/usr/include/klibc/sysconfig.h b/usr/include/klibc/sysconfig.h index bf1daf5..a1c37fd 100644 --- a/usr/include/klibc/sysconfig.h +++ b/usr/include/klibc/sysconfig.h @@ -196,4 +196,13 @@ # define _KLIBC_SYS_SOCKETCALL 0 #endif +/* + * _KLIBC_ARM_USE_BX + * + * This arm architecture supports bx instruction. + */ +#ifndef _KLIBC_ARM_USE_BX +# define _KLIBC_ARM_USE_BX 0 +#endif + #endif /* _KLIBC_SYSCONFIG_H */ diff --git a/usr/klibc/arch/arm/setjmp.S b/usr/klibc/arch/arm/setjmp.S index 2232458..6018bda 100644 --- a/usr/klibc/arch/arm/setjmp.S +++ b/usr/klibc/arch/arm/setjmp.S @@ -4,6 +4,8 @@ # setjmp/longjmp for the ARM architecture # +#include + #ifndef __thumb__ # @@ -29,7 +31,7 @@ setjmp: stmia r0, {r4, r5, r6, r7, r8, r9, r10, fp, sp, lr} mov r0, #0 - mov pc, lr + BX(lr) .size setjmp,.-setjmp .text @@ -39,7 +41,7 @@ setjmp: longjmp: ldmia r0, {r4, r5, r6, r7, r8, r9, r10, fp, sp, lr} mov r0, r1 - mov pc, lr + BX(lr) .size longjmp,.-longjmp #else /* __thumb__ */ @@ -75,7 +77,7 @@ setjmp: mov r7, sp stmia r0!, {r3, r4, r5, r6, r7} mov r0, #0 - mov pc, lr + BX(lr) .size setjmp,.-setjmp .text @@ -96,7 +98,7 @@ longjmp: mov r0, r1 bne 1f mov r0, #1 -1: mov pc, r3 +1: BX(r3) .size longjmp,.-longjmp #endif /* __thumb__ */ diff --git a/usr/klibc/arch/arm/vfork.S b/usr/klibc/arch/arm/vfork.S index 3b2d9f7..7130b65 100644 --- a/usr/klibc/arch/arm/vfork.S +++ b/usr/klibc/arch/arm/vfork.S @@ -4,6 +4,7 @@ * vfork - nasty system call which must not use the stack. */ +#include #include .type vfork,#function @@ -25,7 +26,7 @@ vfork: ldrcs r3, 1f mvncs r0, #0 strcs r2, [r3] - mov pc, lr + BX(lr) .balign 4 1: @@ -49,7 +50,7 @@ vfork: str r2, [r1] neg r0, r0 1: - mov pc, lr + BX(lr) .balign 4 2: -- 1.7.2.5