linux/arch/arm64/kernel/kuser32.S
Jonathan Corbet 263638dc06 arm64: Update Documentation/arm references
The Arm documentation has moved to Documentation/arch/arm; update
references under arch/arm64 to match.

Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-06-12 06:33:48 -06:00

66 lines
1.8 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* AArch32 user helpers.
* Based on the kuser helpers in arch/arm/kernel/entry-armv.S.
*
* Copyright (C) 2005-2011 Nicolas Pitre <nico@fluxnic.net>
* Copyright (C) 2012-2018 ARM Ltd.
*
* The kuser helpers below are mapped at a fixed address by
* aarch32_setup_additional_pages() and are provided for compatibility
* reasons with 32 bit (aarch32) applications that need them.
*
* See Documentation/arch/arm/kernel_user_helpers.rst for formal definitions.
*/
#include <asm/unistd.h>
.section .rodata
.align 5
.globl __kuser_helper_start
__kuser_helper_start:
__kuser_cmpxchg64: // 0xffff0f60
.inst 0xe92d00f0 // push {r4, r5, r6, r7}
.inst 0xe1c040d0 // ldrd r4, r5, [r0]
.inst 0xe1c160d0 // ldrd r6, r7, [r1]
.inst 0xe1b20f9f // 1: ldrexd r0, r1, [r2]
.inst 0xe0303004 // eors r3, r0, r4
.inst 0x00313005 // eoreqs r3, r1, r5
.inst 0x01a23e96 // stlexdeq r3, r6, [r2]
.inst 0x03330001 // teqeq r3, #1
.inst 0x0afffff9 // beq 1b
.inst 0xf57ff05b // dmb ish
.inst 0xe2730000 // rsbs r0, r3, #0
.inst 0xe8bd00f0 // pop {r4, r5, r6, r7}
.inst 0xe12fff1e // bx lr
.align 5
__kuser_memory_barrier: // 0xffff0fa0
.inst 0xf57ff05b // dmb ish
.inst 0xe12fff1e // bx lr
.align 5
__kuser_cmpxchg: // 0xffff0fc0
.inst 0xe1923f9f // 1: ldrex r3, [r2]
.inst 0xe0533000 // subs r3, r3, r0
.inst 0x01823e91 // stlexeq r3, r1, [r2]
.inst 0x03330001 // teqeq r3, #1
.inst 0x0afffffa // beq 1b
.inst 0xf57ff05b // dmb ish
.inst 0xe2730000 // rsbs r0, r3, #0
.inst 0xe12fff1e // bx lr
.align 5
__kuser_get_tls: // 0xffff0fe0
.inst 0xee1d0f70 // mrc p15, 0, r0, c13, c0, 3
.inst 0xe12fff1e // bx lr
.rep 5
.word 0
.endr
__kuser_helper_version: // 0xffff0ffc
.word ((__kuser_helper_end - __kuser_helper_start) >> 5)
.globl __kuser_helper_end
__kuser_helper_end: