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/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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 * Copyright (C) 2025 Chen Miao
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 *
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 * Based on arch/arm/include/asm/jump_label.h
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 */
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#ifndef __ASM_OPENRISC_JUMP_LABEL_H
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#define __ASM_OPENRISC_JUMP_LABEL_H
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#ifndef __ASSEMBLER__
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#include <linux/types.h>
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#include <asm/insn-def.h>
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#define HAVE_JUMP_LABEL_BATCH
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#define JUMP_LABEL_NOP_SIZE OPENRISC_INSN_SIZE
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/**
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 * JUMP_TABLE_ENTRY - Create a jump table entry
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 * @key: Jump key identifier (typically a symbol address)
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 * @label: Target label address
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 *
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 * This macro creates a jump table entry in the dedicated kernel section (__jump_table).
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 * Each entry contains the following information:
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 * 		Offset from current instruction to jump instruction (1b - .)
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 * 		Offset from current instruction to target label (label - .)
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 * 		Offset from current instruction to key identifier (key - .)
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 */
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#define JUMP_TABLE_ENTRY(key, label)			\
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	".pushsection	__jump_table, \"aw\"	\n\t"	\
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	".align 	4 			\n\t"	\
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	".long 		1b - ., " label " - .	\n\t"	\
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	".long 		" key " - . 		\n\t"	\
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	".popsection				\n\t"
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#define ARCH_STATIC_BRANCH_ASM(key, label)		\
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	".align		4			\n\t"	\
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	"1: l.nop				\n\t"	\
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	"    l.nop				\n\t"	\
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	JUMP_TABLE_ENTRY(key, label)
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static __always_inline bool arch_static_branch(struct static_key *const key,
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					       const bool branch)
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{
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	asm goto (ARCH_STATIC_BRANCH_ASM("%0", "%l[l_yes]")
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		  ::"i"(&((char *)key)[branch])::l_yes);
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	return false;
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l_yes:
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	return true;
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}
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#define ARCH_STATIC_BRANCH_JUMP_ASM(key, label)		\
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	".align		4			\n\t"	\
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	"1: l.j	" label "			\n\t"	\
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	"    l.nop				\n\t"	\
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	JUMP_TABLE_ENTRY(key, label)
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static __always_inline bool
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arch_static_branch_jump(struct static_key *const key, const bool branch)
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{
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	asm goto (ARCH_STATIC_BRANCH_JUMP_ASM("%0", "%l[l_yes]")
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		  ::"i"(&((char *)key)[branch])::l_yes);
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	return false;
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l_yes:
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	return true;
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}
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#endif /* __ASSEMBLER__ */
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#endif /* __ASM_OPENRISC_JUMP_LABEL_H */
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