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+/* 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/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: