From f159f4ed55bb0fa5470800641e03a13a7e0eae6e Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Mon, 5 Jul 2010 14:53:10 +0100 Subject: ARM: 6207/1: Replace CONFIG_HAS_TLS_REG with HWCAP_TLS and check for it on V6 The TLS register is only available on ARM1136 r1p0 and later. Set HWCAP_TLS flags if hardware TLS is available and test for it if CONFIG_CPU_32v6K is not set for V6. Note that we set the TLS instruction in __kuser_get_tls dynamically as suggested by Jamie Lokier . Also the __switch_to code is optimized out in most cases as suggested by Nicolas Pitre . Reviewed-by: Nicolas Pitre Signed-off-by: Tony Lindgren Signed-off-by: Russell King --- arch/arm/include/asm/hwcap.h | 1 + arch/arm/include/asm/tls.h | 46 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) create mode 100644 arch/arm/include/asm/tls.h (limited to 'arch/arm/include') diff --git a/arch/arm/include/asm/hwcap.h b/arch/arm/include/asm/hwcap.h index f7bd52b1c365..c1062c317103 100644 --- a/arch/arm/include/asm/hwcap.h +++ b/arch/arm/include/asm/hwcap.h @@ -19,6 +19,7 @@ #define HWCAP_NEON 4096 #define HWCAP_VFPv3 8192 #define HWCAP_VFPv3D16 16384 +#define HWCAP_TLS 32768 #if defined(__KERNEL__) && !defined(__ASSEMBLY__) /* diff --git a/arch/arm/include/asm/tls.h b/arch/arm/include/asm/tls.h new file mode 100644 index 000000000000..e71d6ff8d104 --- /dev/null +++ b/arch/arm/include/asm/tls.h @@ -0,0 +1,46 @@ +#ifndef __ASMARM_TLS_H +#define __ASMARM_TLS_H + +#ifdef __ASSEMBLY__ + .macro set_tls_none, tp, tmp1, tmp2 + .endm + + .macro set_tls_v6k, tp, tmp1, tmp2 + mcr p15, 0, \tp, c13, c0, 3 @ set TLS register + .endm + + .macro set_tls_v6, tp, tmp1, tmp2 + ldr \tmp1, =elf_hwcap + ldr \tmp1, [\tmp1, #0] + mov \tmp2, #0xffff0fff + tst \tmp1, #HWCAP_TLS @ hardware TLS available? + mcrne p15, 0, \tp, c13, c0, 3 @ yes, set TLS register + streq \tp, [\tmp2, #-15] @ set TLS value at 0xffff0ff0 + .endm + + .macro set_tls_software, tp, tmp1, tmp2 + mov \tmp1, #0xffff0fff + str \tp, [\tmp1, #-15] @ set TLS value at 0xffff0ff0 + .endm +#endif + +#ifdef CONFIG_TLS_REG_EMUL +#define tls_emu 1 +#define has_tls_reg 1 +#define set_tls set_tls_none +#elif __LINUX_ARM_ARCH__ >= 7 || \ + (__LINUX_ARM_ARCH__ == 6 && defined(CONFIG_CPU_32v6K)) +#define tls_emu 0 +#define has_tls_reg 1 +#define set_tls set_tls_v6k +#elif __LINUX_ARM_ARCH__ == 6 +#define tls_emu 0 +#define has_tls_reg (elf_hwcap & HWCAP_TLS) +#define set_tls set_tls_v6 +#else +#define tls_emu 0 +#define has_tls_reg 0 +#define set_tls set_tls_software +#endif + +#endif /* __ASMARM_TLS_H */ -- cgit v1.2.1