xref: /linux/arch/powerpc/include/asm/jump_label.h (revision 0340dc4c82590d8735c58cf904a8aa1173273ab5)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _ASM_POWERPC_JUMP_LABEL_H
3 #define _ASM_POWERPC_JUMP_LABEL_H
4 
5 /*
6  * Copyright 2010 Michael Ellerman, IBM Corp.
7  */
8 
9 #ifndef __ASSEMBLY__
10 #include <linux/types.h>
11 
12 #include <asm/feature-fixups.h>
13 #include <asm/asm-const.h>
14 
15 #define JUMP_ENTRY_TYPE		stringify_in_c(FTR_ENTRY_LONG)
16 #define JUMP_LABEL_NOP_SIZE	4
17 
18 static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
19 {
20 	asm goto("1:\n\t"
21 		 "nop # arch_static_branch\n\t"
22 		 ".pushsection __jump_table,  \"aw\"\n\t"
23 		 ".long 1b - ., %l[l_yes] - .\n\t"
24 		 JUMP_ENTRY_TYPE "%c0 - .\n\t"
25 		 ".popsection \n\t"
26 		 : :  "i" (&((char *)key)[branch]) : : l_yes);
27 
28 	return false;
29 l_yes:
30 	return true;
31 }
32 
33 static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
34 {
35 	asm goto("1:\n\t"
36 		 "b %l[l_yes] # arch_static_branch_jump\n\t"
37 		 ".pushsection __jump_table,  \"aw\"\n\t"
38 		 ".long 1b - ., %l[l_yes] - .\n\t"
39 		 JUMP_ENTRY_TYPE "%c0 - .\n\t"
40 		 ".popsection \n\t"
41 		 : :  "i" (&((char *)key)[branch]) : : l_yes);
42 
43 	return false;
44 l_yes:
45 	return true;
46 }
47 
48 #else
49 #define ARCH_STATIC_BRANCH(LABEL, KEY)		\
50 1098:	nop;					\
51 	.pushsection __jump_table, "aw";	\
52 	.long 1098b - ., LABEL - .;		\
53 	FTR_ENTRY_LONG KEY - .;			\
54 	.popsection
55 #endif
56 
57 #endif /* _ASM_POWERPC_JUMP_LABEL_H */
58