xref: /openbmc/linux/arch/x86/include/asm/cpufeature.h (revision 8730046c)
1 #ifndef _ASM_X86_CPUFEATURE_H
2 #define _ASM_X86_CPUFEATURE_H
3 
4 #include <asm/processor.h>
5 
6 #if defined(__KERNEL__) && !defined(__ASSEMBLY__)
7 
8 #include <asm/asm.h>
9 #include <linux/bitops.h>
10 
11 enum cpuid_leafs
12 {
13 	CPUID_1_EDX		= 0,
14 	CPUID_8000_0001_EDX,
15 	CPUID_8086_0001_EDX,
16 	CPUID_LNX_1,
17 	CPUID_1_ECX,
18 	CPUID_C000_0001_EDX,
19 	CPUID_8000_0001_ECX,
20 	CPUID_LNX_2,
21 	CPUID_LNX_3,
22 	CPUID_7_0_EBX,
23 	CPUID_D_1_EAX,
24 	CPUID_F_0_EDX,
25 	CPUID_F_1_EDX,
26 	CPUID_8000_0008_EBX,
27 	CPUID_6_EAX,
28 	CPUID_8000_000A_EDX,
29 	CPUID_7_ECX,
30 	CPUID_8000_0007_EBX,
31 };
32 
33 #ifdef CONFIG_X86_FEATURE_NAMES
34 extern const char * const x86_cap_flags[NCAPINTS*32];
35 extern const char * const x86_power_flags[32];
36 #define X86_CAP_FMT "%s"
37 #define x86_cap_flag(flag) x86_cap_flags[flag]
38 #else
39 #define X86_CAP_FMT "%d:%d"
40 #define x86_cap_flag(flag) ((flag) >> 5), ((flag) & 31)
41 #endif
42 
43 /*
44  * In order to save room, we index into this array by doing
45  * X86_BUG_<name> - NCAPINTS*32.
46  */
47 extern const char * const x86_bug_flags[NBUGINTS*32];
48 
49 #define test_cpu_cap(c, bit)						\
50 	 test_bit(bit, (unsigned long *)((c)->x86_capability))
51 
52 /*
53  * There are 32 bits/features in each mask word.  The high bits
54  * (selected with (bit>>5) give us the word number and the low 5
55  * bits give us the bit/feature number inside the word.
56  * (1UL<<((bit)&31) gives us a mask for the feature_bit so we can
57  * see if it is set in the mask word.
58  */
59 #define CHECK_BIT_IN_MASK_WORD(maskname, word, bit)	\
60 	(((bit)>>5)==(word) && (1UL<<((bit)&31) & maskname##word ))
61 
62 #define REQUIRED_MASK_BIT_SET(feature_bit)		\
63 	 ( CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  0, feature_bit) ||	\
64 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  1, feature_bit) ||	\
65 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  2, feature_bit) ||	\
66 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  3, feature_bit) ||	\
67 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  4, feature_bit) ||	\
68 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  5, feature_bit) ||	\
69 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  6, feature_bit) ||	\
70 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  7, feature_bit) ||	\
71 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  8, feature_bit) ||	\
72 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK,  9, feature_bit) ||	\
73 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 10, feature_bit) ||	\
74 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 11, feature_bit) ||	\
75 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 12, feature_bit) ||	\
76 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 13, feature_bit) ||	\
77 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 14, feature_bit) ||	\
78 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 15, feature_bit) ||	\
79 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 16, feature_bit) ||	\
80 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 17, feature_bit) ||	\
81 	   REQUIRED_MASK_CHECK					  ||	\
82 	   BUILD_BUG_ON_ZERO(NCAPINTS != 18))
83 
84 #define DISABLED_MASK_BIT_SET(feature_bit)				\
85 	 ( CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  0, feature_bit) ||	\
86 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  1, feature_bit) ||	\
87 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  2, feature_bit) ||	\
88 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  3, feature_bit) ||	\
89 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  4, feature_bit) ||	\
90 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  5, feature_bit) ||	\
91 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  6, feature_bit) ||	\
92 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  7, feature_bit) ||	\
93 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  8, feature_bit) ||	\
94 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  9, feature_bit) ||	\
95 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 10, feature_bit) ||	\
96 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 11, feature_bit) ||	\
97 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 12, feature_bit) ||	\
98 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 13, feature_bit) ||	\
99 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 14, feature_bit) ||	\
100 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 15, feature_bit) ||	\
101 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 16, feature_bit) ||	\
102 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 17, feature_bit) ||	\
103 	   DISABLED_MASK_CHECK					  ||	\
104 	   BUILD_BUG_ON_ZERO(NCAPINTS != 18))
105 
106 #define cpu_has(c, bit)							\
107 	(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 :	\
108 	 test_cpu_cap(c, bit))
109 
110 #define this_cpu_has(bit)						\
111 	(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 : 	\
112 	 x86_this_cpu_test_bit(bit, (unsigned long *)&cpu_info.x86_capability))
113 
114 /*
115  * This macro is for detection of features which need kernel
116  * infrastructure to be used.  It may *not* directly test the CPU
117  * itself.  Use the cpu_has() family if you want true runtime
118  * testing of CPU features, like in hypervisor code where you are
119  * supporting a possible guest feature where host support for it
120  * is not relevant.
121  */
122 #define cpu_feature_enabled(bit)	\
123 	(__builtin_constant_p(bit) && DISABLED_MASK_BIT_SET(bit) ? 0 : static_cpu_has(bit))
124 
125 #define boot_cpu_has(bit)	cpu_has(&boot_cpu_data, bit)
126 
127 #define set_cpu_cap(c, bit)	set_bit(bit, (unsigned long *)((c)->x86_capability))
128 #define clear_cpu_cap(c, bit)	clear_bit(bit, (unsigned long *)((c)->x86_capability))
129 #define setup_clear_cpu_cap(bit) do { \
130 	clear_cpu_cap(&boot_cpu_data, bit);	\
131 	set_bit(bit, (unsigned long *)cpu_caps_cleared); \
132 } while (0)
133 #define setup_force_cpu_cap(bit) do { \
134 	set_cpu_cap(&boot_cpu_data, bit);	\
135 	set_bit(bit, (unsigned long *)cpu_caps_set);	\
136 } while (0)
137 
138 #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_X86_FAST_FEATURE_TESTS)
139 /*
140  * Static testing of CPU features.  Used the same as boot_cpu_has().
141  * These will statically patch the target code for additional
142  * performance.
143  */
144 static __always_inline __pure bool _static_cpu_has(u16 bit)
145 {
146 		asm_volatile_goto("1: jmp 6f\n"
147 			 "2:\n"
148 			 ".skip -(((5f-4f) - (2b-1b)) > 0) * "
149 			         "((5f-4f) - (2b-1b)),0x90\n"
150 			 "3:\n"
151 			 ".section .altinstructions,\"a\"\n"
152 			 " .long 1b - .\n"		/* src offset */
153 			 " .long 4f - .\n"		/* repl offset */
154 			 " .word %P1\n"			/* always replace */
155 			 " .byte 3b - 1b\n"		/* src len */
156 			 " .byte 5f - 4f\n"		/* repl len */
157 			 " .byte 3b - 2b\n"		/* pad len */
158 			 ".previous\n"
159 			 ".section .altinstr_replacement,\"ax\"\n"
160 			 "4: jmp %l[t_no]\n"
161 			 "5:\n"
162 			 ".previous\n"
163 			 ".section .altinstructions,\"a\"\n"
164 			 " .long 1b - .\n"		/* src offset */
165 			 " .long 0\n"			/* no replacement */
166 			 " .word %P0\n"			/* feature bit */
167 			 " .byte 3b - 1b\n"		/* src len */
168 			 " .byte 0\n"			/* repl len */
169 			 " .byte 0\n"			/* pad len */
170 			 ".previous\n"
171 			 ".section .altinstr_aux,\"ax\"\n"
172 			 "6:\n"
173 			 " testb %[bitnum],%[cap_byte]\n"
174 			 " jnz %l[t_yes]\n"
175 			 " jmp %l[t_no]\n"
176 			 ".previous\n"
177 			 : : "i" (bit), "i" (X86_FEATURE_ALWAYS),
178 			     [bitnum] "i" (1 << (bit & 7)),
179 			     [cap_byte] "m" (((const char *)boot_cpu_data.x86_capability)[bit >> 3])
180 			 : : t_yes, t_no);
181 	t_yes:
182 		return true;
183 	t_no:
184 		return false;
185 }
186 
187 #define static_cpu_has(bit)					\
188 (								\
189 	__builtin_constant_p(boot_cpu_has(bit)) ?		\
190 		boot_cpu_has(bit) :				\
191 		_static_cpu_has(bit)				\
192 )
193 #else
194 /*
195  * Fall back to dynamic for gcc versions which don't support asm goto. Should be
196  * a minority now anyway.
197  */
198 #define static_cpu_has(bit)		boot_cpu_has(bit)
199 #endif
200 
201 #define cpu_has_bug(c, bit)		cpu_has(c, (bit))
202 #define set_cpu_bug(c, bit)		set_cpu_cap(c, (bit))
203 #define clear_cpu_bug(c, bit)		clear_cpu_cap(c, (bit))
204 
205 #define static_cpu_has_bug(bit)		static_cpu_has((bit))
206 #define boot_cpu_has_bug(bit)		cpu_has_bug(&boot_cpu_data, (bit))
207 #define boot_cpu_set_bug(bit)		set_cpu_cap(&boot_cpu_data, (bit))
208 
209 #define MAX_CPU_FEATURES		(NCAPINTS * 32)
210 #define cpu_have_feature		boot_cpu_has
211 
212 #define CPU_FEATURE_TYPEFMT		"x86,ven%04Xfam%04Xmod%04X"
213 #define CPU_FEATURE_TYPEVAL		boot_cpu_data.x86_vendor, boot_cpu_data.x86, \
214 					boot_cpu_data.x86_model
215 
216 #endif /* defined(__KERNEL__) && !defined(__ASSEMBLY__) */
217 #endif /* _ASM_X86_CPUFEATURE_H */
218