diff options
| author | Tony Lindgren <tony@atomide.com> | 2010-07-05 14:53:10 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-07-09 14:41:35 +0100 |
| commit | f159f4ed55bb0fa5470800641e03a13a7e0eae6e (patch) | |
| tree | c2ed54b103c2a1c58fa4b50740fec462ccfeec74 /arch/arm/include/asm/tls.h | |
| parent | c1b2d9704c77ddaec46d5d681e1360ac40268743 (diff) | |
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 <jamie@shareable.org>.
Also the __switch_to code is optimized out in most cases as
suggested by Nicolas Pitre <nico@fluxnic.net>.
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/include/asm/tls.h')
| -rw-r--r-- | arch/arm/include/asm/tls.h | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/arch/arm/include/asm/tls.h b/arch/arm/include/asm/tls.h new file mode 100644 index 00000000000..e71d6ff8d10 --- /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 */ |