xref: /openbmc/linux/arch/mips/include/asm/jump_label.h (revision a06c488d)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (c) 2010 Cavium Networks, Inc.
7  */
8 #ifndef _ASM_MIPS_JUMP_LABEL_H
9 #define _ASM_MIPS_JUMP_LABEL_H
10 
11 #ifndef __ASSEMBLY__
12 
13 #include <linux/types.h>
14 
15 #define JUMP_LABEL_NOP_SIZE 4
16 
17 #ifdef CONFIG_64BIT
18 #define WORD_INSN ".dword"
19 #else
20 #define WORD_INSN ".word"
21 #endif
22 
23 #ifdef CONFIG_CPU_MICROMIPS
24 #define NOP_INSN "nop32"
25 #else
26 #define NOP_INSN "nop"
27 #endif
28 
29 static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
30 {
31 	asm_volatile_goto("1:\t" NOP_INSN "\n\t"
32 		"nop\n\t"
33 		".pushsection __jump_table,  \"aw\"\n\t"
34 		WORD_INSN " 1b, %l[l_yes], %0\n\t"
35 		".popsection\n\t"
36 		: :  "i" (&((char *)key)[branch]) : : l_yes);
37 
38 	return false;
39 l_yes:
40 	return true;
41 }
42 
43 static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
44 {
45 	asm_volatile_goto("1:\tj %l[l_yes]\n\t"
46 		"nop\n\t"
47 		".pushsection __jump_table,  \"aw\"\n\t"
48 		WORD_INSN " 1b, %l[l_yes], %0\n\t"
49 		".popsection\n\t"
50 		: :  "i" (&((char *)key)[branch]) : : l_yes);
51 
52 	return false;
53 l_yes:
54 	return true;
55 }
56 
57 #ifdef CONFIG_64BIT
58 typedef u64 jump_label_t;
59 #else
60 typedef u32 jump_label_t;
61 #endif
62 
63 struct jump_entry {
64 	jump_label_t code;
65 	jump_label_t target;
66 	jump_label_t key;
67 };
68 
69 #endif  /* __ASSEMBLY__ */
70 #endif /* _ASM_MIPS_JUMP_LABEL_H */
71