xref: /openbmc/linux/arch/x86/include/asm/asm.h (revision 82e6fdd6)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_ASM_H
3 #define _ASM_X86_ASM_H
4 
5 #ifdef __ASSEMBLY__
6 # define __ASM_FORM(x)	x
7 # define __ASM_FORM_RAW(x)     x
8 # define __ASM_FORM_COMMA(x) x,
9 #else
10 # define __ASM_FORM(x)	" " #x " "
11 # define __ASM_FORM_RAW(x)     #x
12 # define __ASM_FORM_COMMA(x) " " #x ","
13 #endif
14 
15 #ifndef __x86_64__
16 /* 32 bit */
17 # define __ASM_SEL(a,b) __ASM_FORM(a)
18 # define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
19 #else
20 /* 64 bit */
21 # define __ASM_SEL(a,b) __ASM_FORM(b)
22 # define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
23 #endif
24 
25 #define __ASM_SIZE(inst, ...)	__ASM_SEL(inst##l##__VA_ARGS__, \
26 					  inst##q##__VA_ARGS__)
27 #define __ASM_REG(reg)         __ASM_SEL_RAW(e##reg, r##reg)
28 
29 #define _ASM_PTR	__ASM_SEL(.long, .quad)
30 #define _ASM_ALIGN	__ASM_SEL(.balign 4, .balign 8)
31 
32 #define _ASM_MOV	__ASM_SIZE(mov)
33 #define _ASM_INC	__ASM_SIZE(inc)
34 #define _ASM_DEC	__ASM_SIZE(dec)
35 #define _ASM_ADD	__ASM_SIZE(add)
36 #define _ASM_SUB	__ASM_SIZE(sub)
37 #define _ASM_XADD	__ASM_SIZE(xadd)
38 #define _ASM_MUL	__ASM_SIZE(mul)
39 
40 #define _ASM_AX		__ASM_REG(ax)
41 #define _ASM_BX		__ASM_REG(bx)
42 #define _ASM_CX		__ASM_REG(cx)
43 #define _ASM_DX		__ASM_REG(dx)
44 #define _ASM_SP		__ASM_REG(sp)
45 #define _ASM_BP		__ASM_REG(bp)
46 #define _ASM_SI		__ASM_REG(si)
47 #define _ASM_DI		__ASM_REG(di)
48 
49 /*
50  * Macros to generate condition code outputs from inline assembly,
51  * The output operand must be type "bool".
52  */
53 #ifdef __GCC_ASM_FLAG_OUTPUTS__
54 # define CC_SET(c) "\n\t/* output condition code " #c "*/\n"
55 # define CC_OUT(c) "=@cc" #c
56 #else
57 # define CC_SET(c) "\n\tset" #c " %[_cc_" #c "]\n"
58 # define CC_OUT(c) [_cc_ ## c] "=qm"
59 #endif
60 
61 /* Exception table entry */
62 #ifdef __ASSEMBLY__
63 # define _ASM_EXTABLE_HANDLE(from, to, handler)			\
64 	.pushsection "__ex_table","a" ;				\
65 	.balign 4 ;						\
66 	.long (from) - . ;					\
67 	.long (to) - . ;					\
68 	.long (handler) - . ;					\
69 	.popsection
70 
71 # define _ASM_EXTABLE(from, to)					\
72 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
73 
74 # define _ASM_EXTABLE_FAULT(from, to)				\
75 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
76 
77 # define _ASM_EXTABLE_EX(from, to)				\
78 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
79 
80 # define _ASM_EXTABLE_REFCOUNT(from, to)			\
81 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
82 
83 # define _ASM_NOKPROBE(entry)					\
84 	.pushsection "_kprobe_blacklist","aw" ;			\
85 	_ASM_ALIGN ;						\
86 	_ASM_PTR (entry);					\
87 	.popsection
88 
89 .macro ALIGN_DESTINATION
90 	/* check for bad alignment of destination */
91 	movl %edi,%ecx
92 	andl $7,%ecx
93 	jz 102f				/* already aligned */
94 	subl $8,%ecx
95 	negl %ecx
96 	subl %ecx,%edx
97 100:	movb (%rsi),%al
98 101:	movb %al,(%rdi)
99 	incq %rsi
100 	incq %rdi
101 	decl %ecx
102 	jnz 100b
103 102:
104 	.section .fixup,"ax"
105 103:	addl %ecx,%edx			/* ecx is zerorest also */
106 	jmp copy_user_handle_tail
107 	.previous
108 
109 	_ASM_EXTABLE(100b,103b)
110 	_ASM_EXTABLE(101b,103b)
111 	.endm
112 
113 #else
114 # define _EXPAND_EXTABLE_HANDLE(x) #x
115 # define _ASM_EXTABLE_HANDLE(from, to, handler)			\
116 	" .pushsection \"__ex_table\",\"a\"\n"			\
117 	" .balign 4\n"						\
118 	" .long (" #from ") - .\n"				\
119 	" .long (" #to ") - .\n"				\
120 	" .long (" _EXPAND_EXTABLE_HANDLE(handler) ") - .\n"	\
121 	" .popsection\n"
122 
123 # define _ASM_EXTABLE(from, to)					\
124 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
125 
126 # define _ASM_EXTABLE_FAULT(from, to)				\
127 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
128 
129 # define _ASM_EXTABLE_EX(from, to)				\
130 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
131 
132 # define _ASM_EXTABLE_REFCOUNT(from, to)			\
133 	_ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
134 
135 /* For C file, we already have NOKPROBE_SYMBOL macro */
136 #endif
137 
138 #ifndef __ASSEMBLY__
139 #ifndef __BPF__
140 /*
141  * This output constraint should be used for any inline asm which has a "call"
142  * instruction.  Otherwise the asm may be inserted before the frame pointer
143  * gets set up by the containing function.  If you forget to do this, objtool
144  * may print a "call without frame pointer save/setup" warning.
145  */
146 register unsigned long current_stack_pointer asm(_ASM_SP);
147 #define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer)
148 #endif
149 #endif
150 
151 #endif /* _ASM_X86_ASM_H */
152