mirror of
https://git.proxmox.com/git/mirror_ubuntu-kernels.git
synced 2026-01-06 03:53:44 +00:00
d6905849f8
Nathan reports the group relocations go out of range in pathological cases such as allyesconfig kernels, which have little chance of actually booting but are still used in validation. So add a Kconfig symbol for this feature, and make it depend on !COMPILE_TEST. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
71 lines
1.7 KiB
C
71 lines
1.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Copyright 2012 Calxeda, Inc.
|
|
*/
|
|
#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
|
|
*/
|
|
#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)
|
|
{
|
|
unsigned long off;
|
|
|
|
/*
|
|
* Read TPIDRPRW.
|
|
* We want to allow caching the value, so avoid using volatile and
|
|
* instead use a fake stack read to hazard against barrier().
|
|
*/
|
|
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;
|
|
}
|
|
#define __my_cpu_offset __my_cpu_offset()
|
|
#else
|
|
#define set_my_cpu_offset(x) do {} while(0)
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
#include <asm-generic/percpu.h>
|
|
|
|
#endif /* _ASM_ARM_PERCPU_H_ */
|