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Diffstat (limited to 'arch/arm/include/asm/percpu.h')
-rw-r--r--arch/arm/include/asm/percpu.h35
1 files changed, 31 insertions, 4 deletions
diff --git a/arch/arm/include/asm/percpu.h b/arch/arm/include/asm/percpu.h
index e2fcb3cfd3de..7545c87c251f 100644
--- a/arch/arm/include/asm/percpu.h
+++ b/arch/arm/include/asm/percpu.h
@@ -5,20 +5,27 @@
#ifndef _ASM_ARM_PERCPU_H_
#define _ASM_ARM_PERCPU_H_
+#include <asm/insn.h>
+
register unsigned long current_stack_pointer asm ("sp");
/*
* Same as asm-generic/percpu.h, except that we store the per cpu offset
* in the TPIDRPRW. TPIDRPRW only exists on V6K and V7
*/
-#if defined(CONFIG_SMP) && !defined(CONFIG_CPU_V6)
+#ifdef CONFIG_SMP
static inline void set_my_cpu_offset(unsigned long off)
{
+ extern unsigned int smp_on_up;
+
+ if (IS_ENABLED(CONFIG_CPU_V6) && !smp_on_up)
+ return;
+
/* Set TPIDRPRW */
asm volatile("mcr p15, 0, %0, c13, c0, 4" : : "r" (off) : "memory");
}
-static inline unsigned long __my_cpu_offset(void)
+static __always_inline unsigned long __my_cpu_offset(void)
{
unsigned long off;
@@ -27,8 +34,28 @@ static inline unsigned long __my_cpu_offset(void)
* We want to allow caching the value, so avoid using volatile and
* instead use a fake stack read to hazard against barrier().
*/
- asm("mrc p15, 0, %0, c13, c0, 4" : "=r" (off)
- : "Q" (*(const unsigned long *)current_stack_pointer));
+ asm("0: mrc p15, 0, %0, c13, c0, 4 \n\t"
+#ifdef CONFIG_CPU_V6
+ "1: \n\t"
+ " .subsection 1 \n\t"
+#if defined(CONFIG_ARM_HAS_GROUP_RELOCS) && \
+ !(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
+ "2: " LOAD_SYM_ARMV6(%0, __per_cpu_offset) " \n\t"
+ " b 1b \n\t"
+#else
+ "2: ldr %0, 3f \n\t"
+ " ldr %0, [%0] \n\t"
+ " b 1b \n\t"
+ "3: .long __per_cpu_offset \n\t"
+#endif
+ " .previous \n\t"
+ " .pushsection \".alt.smp.init\", \"a\" \n\t"
+ " .long 0b - . \n\t"
+ " b . + (2b - 0b) \n\t"
+ " .popsection \n\t"
+#endif
+ : "=r" (off)
+ : "Q" (*(const unsigned long *)current_stack_pointer));
return off;
}