arch/x86/include/asm/cpufeature.h at v4.7

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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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kernel / arch / x86 / include / asm / cpufeature.h
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  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
 11enum 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
 34extern const char * const x86_cap_flags[NCAPINTS*32];
 35extern 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 */
 47extern 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#define REQUIRED_MASK_BIT_SET(bit)					\
 53	 ( (((bit)>>5)==0  && (1UL<<((bit)&31) & REQUIRED_MASK0 )) ||	\
 54	   (((bit)>>5)==1  && (1UL<<((bit)&31) & REQUIRED_MASK1 )) ||	\
 55	   (((bit)>>5)==2  && (1UL<<((bit)&31) & REQUIRED_MASK2 )) ||	\
 56	   (((bit)>>5)==3  && (1UL<<((bit)&31) & REQUIRED_MASK3 )) ||	\
 57	   (((bit)>>5)==4  && (1UL<<((bit)&31) & REQUIRED_MASK4 )) ||	\
 58	   (((bit)>>5)==5  && (1UL<<((bit)&31) & REQUIRED_MASK5 )) ||	\
 59	   (((bit)>>5)==6  && (1UL<<((bit)&31) & REQUIRED_MASK6 )) ||	\
 60	   (((bit)>>5)==7  && (1UL<<((bit)&31) & REQUIRED_MASK7 )) ||	\
 61	   (((bit)>>5)==8  && (1UL<<((bit)&31) & REQUIRED_MASK8 )) ||	\
 62	   (((bit)>>5)==9  && (1UL<<((bit)&31) & REQUIRED_MASK9 )) ||	\
 63	   (((bit)>>5)==10 && (1UL<<((bit)&31) & REQUIRED_MASK10)) ||	\
 64	   (((bit)>>5)==11 && (1UL<<((bit)&31) & REQUIRED_MASK11)) ||	\
 65	   (((bit)>>5)==12 && (1UL<<((bit)&31) & REQUIRED_MASK12)) ||	\
 66	   (((bit)>>5)==13 && (1UL<<((bit)&31) & REQUIRED_MASK13)) ||	\
 67	   (((bit)>>5)==14 && (1UL<<((bit)&31) & REQUIRED_MASK14)) ||	\
 68	   (((bit)>>5)==15 && (1UL<<((bit)&31) & REQUIRED_MASK15)) ||	\
 69	   (((bit)>>5)==16 && (1UL<<((bit)&31) & REQUIRED_MASK16)) )
 70
 71#define DISABLED_MASK_BIT_SET(bit)					\
 72	 ( (((bit)>>5)==0  && (1UL<<((bit)&31) & DISABLED_MASK0 )) ||	\
 73	   (((bit)>>5)==1  && (1UL<<((bit)&31) & DISABLED_MASK1 )) ||	\
 74	   (((bit)>>5)==2  && (1UL<<((bit)&31) & DISABLED_MASK2 )) ||	\
 75	   (((bit)>>5)==3  && (1UL<<((bit)&31) & DISABLED_MASK3 )) ||	\
 76	   (((bit)>>5)==4  && (1UL<<((bit)&31) & DISABLED_MASK4 )) ||	\
 77	   (((bit)>>5)==5  && (1UL<<((bit)&31) & DISABLED_MASK5 )) ||	\
 78	   (((bit)>>5)==6  && (1UL<<((bit)&31) & DISABLED_MASK6 )) ||	\
 79	   (((bit)>>5)==7  && (1UL<<((bit)&31) & DISABLED_MASK7 )) ||	\
 80	   (((bit)>>5)==8  && (1UL<<((bit)&31) & DISABLED_MASK8 )) ||	\
 81	   (((bit)>>5)==9  && (1UL<<((bit)&31) & DISABLED_MASK9 )) ||	\
 82	   (((bit)>>5)==10 && (1UL<<((bit)&31) & DISABLED_MASK10)) ||	\
 83	   (((bit)>>5)==11 && (1UL<<((bit)&31) & DISABLED_MASK11)) ||	\
 84	   (((bit)>>5)==12 && (1UL<<((bit)&31) & DISABLED_MASK12)) ||	\
 85	   (((bit)>>5)==13 && (1UL<<((bit)&31) & DISABLED_MASK13)) ||	\
 86	   (((bit)>>5)==14 && (1UL<<((bit)&31) & DISABLED_MASK14)) ||	\
 87	   (((bit)>>5)==15 && (1UL<<((bit)&31) & DISABLED_MASK15)) ||	\
 88	   (((bit)>>5)==16 && (1UL<<((bit)&31) & DISABLED_MASK16)) )
 89
 90#define cpu_has(c, bit)							\
 91	(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 :	\
 92	 test_cpu_cap(c, bit))
 93
 94#define this_cpu_has(bit)						\
 95	(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 : 	\
 96	 x86_this_cpu_test_bit(bit, (unsigned long *)&cpu_info.x86_capability))
 97
 98/*
 99 * This macro is for detection of features which need kernel
100 * infrastructure to be used.  It may *not* directly test the CPU
101 * itself.  Use the cpu_has() family if you want true runtime
102 * testing of CPU features, like in hypervisor code where you are
103 * supporting a possible guest feature where host support for it
104 * is not relevant.
105 */
106#define cpu_feature_enabled(bit)	\
107	(__builtin_constant_p(bit) && DISABLED_MASK_BIT_SET(bit) ? 0 : static_cpu_has(bit))
108
109#define boot_cpu_has(bit)	cpu_has(&boot_cpu_data, bit)
110
111#define set_cpu_cap(c, bit)	set_bit(bit, (unsigned long *)((c)->x86_capability))
112#define clear_cpu_cap(c, bit)	clear_bit(bit, (unsigned long *)((c)->x86_capability))
113#define setup_clear_cpu_cap(bit) do { \
114	clear_cpu_cap(&boot_cpu_data, bit);	\
115	set_bit(bit, (unsigned long *)cpu_caps_cleared); \
116} while (0)
117#define setup_force_cpu_cap(bit) do { \
118	set_cpu_cap(&boot_cpu_data, bit);	\
119	set_bit(bit, (unsigned long *)cpu_caps_set);	\
120} while (0)
121
122#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_X86_FAST_FEATURE_TESTS)
123/*
124 * Static testing of CPU features.  Used the same as boot_cpu_has().
125 * These will statically patch the target code for additional
126 * performance.
127 */
128static __always_inline __pure bool _static_cpu_has(u16 bit)
129{
130		asm_volatile_goto("1: jmp 6f\n"
131			 "2:\n"
132			 ".skip -(((5f-4f) - (2b-1b)) > 0) * "
133			         "((5f-4f) - (2b-1b)),0x90\n"
134			 "3:\n"
135			 ".section .altinstructions,\"a\"\n"
136			 " .long 1b - .\n"		/* src offset */
137			 " .long 4f - .\n"		/* repl offset */
138			 " .word %P1\n"			/* always replace */
139			 " .byte 3b - 1b\n"		/* src len */
140			 " .byte 5f - 4f\n"		/* repl len */
141			 " .byte 3b - 2b\n"		/* pad len */
142			 ".previous\n"
143			 ".section .altinstr_replacement,\"ax\"\n"
144			 "4: jmp %l[t_no]\n"
145			 "5:\n"
146			 ".previous\n"
147			 ".section .altinstructions,\"a\"\n"
148			 " .long 1b - .\n"		/* src offset */
149			 " .long 0\n"			/* no replacement */
150			 " .word %P0\n"			/* feature bit */
151			 " .byte 3b - 1b\n"		/* src len */
152			 " .byte 0\n"			/* repl len */
153			 " .byte 0\n"			/* pad len */
154			 ".previous\n"
155			 ".section .altinstr_aux,\"ax\"\n"
156			 "6:\n"
157			 " testb %[bitnum],%[cap_byte]\n"
158			 " jnz %l[t_yes]\n"
159			 " jmp %l[t_no]\n"
160			 ".previous\n"
161			 : : "i" (bit), "i" (X86_FEATURE_ALWAYS),
162			     [bitnum] "i" (1 << (bit & 7)),
163			     [cap_byte] "m" (((const char *)boot_cpu_data.x86_capability)[bit >> 3])
164			 : : t_yes, t_no);
165	t_yes:
166		return true;
167	t_no:
168		return false;
169}
170
171#define static_cpu_has(bit)					\
172(								\
173	__builtin_constant_p(boot_cpu_has(bit)) ?		\
174		boot_cpu_has(bit) :				\
175		_static_cpu_has(bit)				\
176)
177#else
178/*
179 * Fall back to dynamic for gcc versions which don't support asm goto. Should be
180 * a minority now anyway.
181 */
182#define static_cpu_has(bit)		boot_cpu_has(bit)
183#endif
184
185#define cpu_has_bug(c, bit)		cpu_has(c, (bit))
186#define set_cpu_bug(c, bit)		set_cpu_cap(c, (bit))
187#define clear_cpu_bug(c, bit)		clear_cpu_cap(c, (bit))
188
189#define static_cpu_has_bug(bit)		static_cpu_has((bit))
190#define boot_cpu_has_bug(bit)		cpu_has_bug(&boot_cpu_data, (bit))
191
192#define MAX_CPU_FEATURES		(NCAPINTS * 32)
193#define cpu_have_feature		boot_cpu_has
194
195#define CPU_FEATURE_TYPEFMT		"x86,ven%04Xfam%04Xmod%04X"
196#define CPU_FEATURE_TYPEVAL		boot_cpu_data.x86_vendor, boot_cpu_data.x86, \
197					boot_cpu_data.x86_model
198
199#endif /* defined(__KERNEL__) && !defined(__ASSEMBLY__) */
200#endif /* _ASM_X86_CPUFEATURE_H */
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