xref: /openbmc/linux/arch/arm64/include/asm/linkage.h (revision 52beb1fc)
1 #ifndef __ASM_LINKAGE_H
2 #define __ASM_LINKAGE_H
3 
4 #ifdef __ASSEMBLY__
5 #include <asm/assembler.h>
6 #endif
7 
8 #define __ALIGN		.align 2
9 #define __ALIGN_STR	".align 2"
10 
11 /*
12  * When using in-kernel BTI we need to ensure that PCS-conformant
13  * assembly functions have suitable annotations.  Override
14  * SYM_FUNC_START to insert a BTI landing pad at the start of
15  * everything, the override is done unconditionally so we're more
16  * likely to notice any drift from the overridden definitions.
17  */
18 #define SYM_FUNC_START(name)				\
19 	SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)	\
20 	bti c ;
21 
22 #define SYM_FUNC_START_NOALIGN(name)			\
23 	SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE)	\
24 	bti c ;
25 
26 #define SYM_FUNC_START_LOCAL(name)			\
27 	SYM_START(name, SYM_L_LOCAL, SYM_A_ALIGN)	\
28 	bti c ;
29 
30 #define SYM_FUNC_START_LOCAL_NOALIGN(name)		\
31 	SYM_START(name, SYM_L_LOCAL, SYM_A_NONE)	\
32 	bti c ;
33 
34 #define SYM_FUNC_START_WEAK(name)			\
35 	SYM_START(name, SYM_L_WEAK, SYM_A_ALIGN)	\
36 	bti c ;
37 
38 #define SYM_FUNC_START_WEAK_NOALIGN(name)		\
39 	SYM_START(name, SYM_L_WEAK, SYM_A_NONE)		\
40 	bti c ;
41 
42 /*
43  * Annotate a function as position independent, i.e., safe to be called before
44  * the kernel virtual mapping is activated.
45  */
46 #define SYM_FUNC_START_PI(x)			\
47 		SYM_FUNC_START_ALIAS(__pi_##x);	\
48 		SYM_FUNC_START(x)
49 
50 #define SYM_FUNC_START_WEAK_PI(x)		\
51 		SYM_FUNC_START_ALIAS(__pi_##x);	\
52 		SYM_FUNC_START_WEAK(x)
53 
54 #define SYM_FUNC_START_WEAK_ALIAS_PI(x)		\
55 		SYM_FUNC_START_ALIAS(__pi_##x);	\
56 		SYM_START(x, SYM_L_WEAK, SYM_A_ALIGN)
57 
58 #define SYM_FUNC_END_PI(x)			\
59 		SYM_FUNC_END(x);		\
60 		SYM_FUNC_END_ALIAS(__pi_##x)
61 
62 #define SYM_FUNC_END_ALIAS_PI(x)		\
63 		SYM_FUNC_END_ALIAS(x);		\
64 		SYM_FUNC_END_ALIAS(__pi_##x)
65 
66 #endif
67