1 /* SPDX-License-Identifier: GPL-2.0 */ 1
2 #ifndef _ASM_UM_CPUFEATURE_H
3 #define _ASM_UM_CPUFEATURE_H
4
5 #include <asm/processor.h>
6
7 #if defined(__KERNEL__) && !defined(__ASSEMBLY
8
9 #include <asm/asm.h>
10 #include <linux/bitops.h>
11
12 extern const char * const x86_cap_flags[NCAPIN
13 extern const char * const x86_power_flags[32];
14 #define X86_CAP_FMT "%s"
15 #define x86_cap_flag(flag) x86_cap_flags[flag]
16
17 /*
18 * In order to save room, we index into this a
19 * X86_BUG_<name> - NCAPINTS*32.
20 */
21 extern const char * const x86_bug_flags[NBUGIN
22
23 #define test_cpu_cap(c, bit)
24 test_bit(bit, (unsigned long *)((c)->
25
26 /*
27 * There are 32 bits/features in each mask wor
28 * (selected with (bit>>5) give us the word nu
29 * bits give us the bit/feature number inside
30 * (1UL<<((bit)&31) gives us a mask for the fe
31 * see if it is set in the mask word.
32 */
33 #define CHECK_BIT_IN_MASK_WORD(maskname, word,
34 (((bit)>>5)==(word) && (1UL<<((bit)&31
35
36 #define cpu_has(c, bit)
37 test_cpu_cap(c, bit)
38
39 #define this_cpu_has(bit)
40 (__builtin_constant_p(bit) && REQUIRED
41 x86_this_cpu_test_bit(bit, cpu_info.x
42
43 /*
44 * This macro is for detection of features whi
45 * infrastructure to be used. It may *not* di
46 * itself. Use the cpu_has() family if you wa
47 * testing of CPU features, like in hypervisor
48 * supporting a possible guest feature where h
49 * is not relevant.
50 */
51 #define cpu_feature_enabled(bit) \
52 (__builtin_constant_p(bit) && DISABLED
53
54 #define boot_cpu_has(bit) cpu_has(&boot_
55
56 #define set_cpu_cap(c, bit) set_bit(bit, (
57
58 extern void setup_clear_cpu_cap(unsigned int b
59
60 #define setup_force_cpu_cap(bit) do { \
61 set_cpu_cap(&boot_cpu_data, bit);
62 set_bit(bit, (unsigned long *)cpu_caps
63 } while (0)
64
65 #define setup_force_cpu_bug(bit) setup_force_c
66
67 /*
68 * Static testing of CPU features. Used the sa
69 * statically patches the target code for addi
70 * static_cpu_has() only in fast paths, where
71 * means that the boot_cpu_has() variant is al
72 * majority of cases and you should stick to u
73 * only two instructions: a RIP-relative MOV a
74 */
75 static __always_inline bool _static_cpu_has(u1
76 {
77 asm goto("1: jmp 6f\n"
78 "2:\n"
79 ".skip -(((5f-4f) - (2b-1b))
80 "((5f-4f) - (2b-1b)),
81 "3:\n"
82 ".section .altinstructions,\"
83 " .long 1b - .\n"
84 " .long 4f - .\n"
85 " .word %P[always]\n"
86 " .byte 3b - 1b\n"
87 " .byte 5f - 4f\n"
88 " .byte 3b - 2b\n"
89 ".previous\n"
90 ".section .altinstr_replaceme
91 "4: jmp %l[t_no]\n"
92 "5:\n"
93 ".previous\n"
94 ".section .altinstructions,\"
95 " .long 1b - .\n"
96 " .long 0\n"
97 " .word %P[feature]\n"
98 " .byte 3b - 1b\n"
99 " .byte 0\n"
100 " .byte 0\n"
101 ".previous\n"
102 ".section .altinstr_aux,\"ax\
103 "6:\n"
104 " testb %[bitnum],%[cap_byte]
105 " jnz %l[t_yes]\n"
106 " jmp %l[t_no]\n"
107 ".previous\n"
108 : : [feature] "i" (bit),
109 [always] "i" (X86_FEATU
110 [bitnum] "i" (1 << (bit
111 [cap_byte] "m" (((const c
112 : : t_yes, t_no);
113 t_yes:
114 return true;
115 t_no:
116 return false;
117 }
118
119 #define static_cpu_has(bit)
120 (
121 __builtin_constant_p(boot_cpu_has(bit)
122 boot_cpu_has(bit) :
123 _static_cpu_has(bit)
124 )
125
126 #define cpu_has_bug(c, bit) cpu_ha
127 #define set_cpu_bug(c, bit) set_cp
128
129 #define static_cpu_has_bug(bit) static
130 #define boot_cpu_has_bug(bit) cpu_ha
131 #define boot_cpu_set_bug(bit) set_cp
132
133 #define MAX_CPU_FEATURES (NCAPI
134 #define cpu_have_feature boot_c
135
136 #define CPU_FEATURE_TYPEFMT "x86,v
137 #define CPU_FEATURE_TYPEVAL boot_c
138 boot_c
139
140 #endif /* defined(__KERNEL__) && !defined(__AS
141 #endif /* _ASM_UM_CPUFEATURE_H */
142
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