From 4b0e07a5566a4e3f141e52c1f17e683e4a5bba91 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Thu, 5 May 2005 23:24:45 +0100 Subject: [PATCH] ARM: 2663/1: straightify TLS register emulation a bit more Patch from Nicolas Pitre This better express things, and should cover RMK's weird SMP toys. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King --- arch/arm/kernel/entry-armv.S | 10 +++------- arch/arm/kernel/traps.c | 11 +++++++---- 2 files changed, 10 insertions(+), 11 deletions(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 080df907f24..c6af1a03e08 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -505,9 +505,9 @@ ENTRY(__switch_to) mra r4, r5, acc0 stmia ip, {r4, r5} #endif -#ifdef CONFIG_HAS_TLS_REG +#if defined(CONFIG_HAS_TLS_REG) mcr p15, 0, r3, c13, c0, 3 @ set TLS register -#else +#elif !defined(CONFIG_TLS_REG_EMUL) mov r4, #0xffff0fff str r3, [r4, #-15] @ TLS val at 0xffff0ff0 #endif @@ -690,11 +690,7 @@ __kuser_cmpxchg: @ 0xffff0fc0 __kuser_get_tls: @ 0xffff0fe0 -#ifndef CONFIG_HAS_TLS_REG - -#ifdef CONFIG_SMP /* sanity check */ -#error "CONFIG_SMP without CONFIG_HAS_TLS_REG is wrong" -#endif +#if !defined(CONFIG_HAS_TLS_REG) && !defined(CONFIG_TLS_REG_EMUL) ldr r0, [pc, #(16 - 8)] @ TLS stored at 0xffff0ff0 mov pc, lr diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 8988c02119f..14df16b983f 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -451,9 +451,9 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) case NR(set_tls): thread->tp_value = regs->ARM_r0; -#ifdef CONFIG_HAS_TLS_REG +#if defined(CONFIG_HAS_TLS_REG) asm ("mcr p15, 0, %0, c13, c0, 3" : : "r" (regs->ARM_r0) ); -#else +#elif !defined(CONFIG_TLS_REG_EMUL) /* * User space must never try to access this directly. * Expect your app to break eventually if you do so. @@ -498,11 +498,14 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) return 0; } -#if defined(CONFIG_CPU_32v6) && !defined(CONFIG_HAS_TLS_REG) +#ifdef CONFIG_TLS_REG_EMUL /* * We might be running on an ARMv6+ processor which should have the TLS - * register, but for some reason we can't use it and have to emulate it. + * register but for some reason we can't use it, or maybe an SMP system + * using a pre-ARMv6 processor (there are apparently a few prototypes like + * that in existence) and therefore access to that register must be + * emulated. */ static int get_tp_trap(struct pt_regs *regs, unsigned int instr) -- cgit v1.2.2