xref: /OK3568_Linux_fs/kernel/arch/riscv/include/asm/jump_label.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2020 Emil Renner Berthing
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Based on arch/arm64/include/asm/jump_label.h
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun #ifndef __ASM_JUMP_LABEL_H
8*4882a593Smuzhiyun #define __ASM_JUMP_LABEL_H
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #ifndef __ASSEMBLY__
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <linux/types.h>
13*4882a593Smuzhiyun #include <asm/asm.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun #define JUMP_LABEL_NOP_SIZE 4
16*4882a593Smuzhiyun 
arch_static_branch(struct static_key * key,bool branch)17*4882a593Smuzhiyun static __always_inline bool arch_static_branch(struct static_key *key,
18*4882a593Smuzhiyun 					       bool branch)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun 	asm_volatile_goto(
21*4882a593Smuzhiyun 		"	.option push				\n\t"
22*4882a593Smuzhiyun 		"	.option norelax				\n\t"
23*4882a593Smuzhiyun 		"	.option norvc				\n\t"
24*4882a593Smuzhiyun 		"1:	nop					\n\t"
25*4882a593Smuzhiyun 		"	.option pop				\n\t"
26*4882a593Smuzhiyun 		"	.pushsection	__jump_table, \"aw\"	\n\t"
27*4882a593Smuzhiyun 		"	.align		" RISCV_LGPTR "		\n\t"
28*4882a593Smuzhiyun 		"	.long		1b - ., %l[label] - .	\n\t"
29*4882a593Smuzhiyun 		"	" RISCV_PTR "	%0 - .			\n\t"
30*4882a593Smuzhiyun 		"	.popsection				\n\t"
31*4882a593Smuzhiyun 		:  :  "i"(&((char *)key)[branch]) :  : label);
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun 	return false;
34*4882a593Smuzhiyun label:
35*4882a593Smuzhiyun 	return true;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun 
arch_static_branch_jump(struct static_key * key,bool branch)38*4882a593Smuzhiyun static __always_inline bool arch_static_branch_jump(struct static_key *key,
39*4882a593Smuzhiyun 						    bool branch)
40*4882a593Smuzhiyun {
41*4882a593Smuzhiyun 	asm_volatile_goto(
42*4882a593Smuzhiyun 		"	.option push				\n\t"
43*4882a593Smuzhiyun 		"	.option norelax				\n\t"
44*4882a593Smuzhiyun 		"	.option norvc				\n\t"
45*4882a593Smuzhiyun 		"1:	jal		zero, %l[label]		\n\t"
46*4882a593Smuzhiyun 		"	.option pop				\n\t"
47*4882a593Smuzhiyun 		"	.pushsection	__jump_table, \"aw\"	\n\t"
48*4882a593Smuzhiyun 		"	.align		" RISCV_LGPTR "		\n\t"
49*4882a593Smuzhiyun 		"	.long		1b - ., %l[label] - .	\n\t"
50*4882a593Smuzhiyun 		"	" RISCV_PTR "	%0 - .			\n\t"
51*4882a593Smuzhiyun 		"	.popsection				\n\t"
52*4882a593Smuzhiyun 		:  :  "i"(&((char *)key)[branch]) :  : label);
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	return false;
55*4882a593Smuzhiyun label:
56*4882a593Smuzhiyun 	return true;
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun #endif  /* __ASSEMBLY__ */
60*4882a593Smuzhiyun #endif	/* __ASM_JUMP_LABEL_H */
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