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x86, cpu: Support the features flags in new CPUID leaf 7
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Intel has defined CPUID leaf 7 as the next set of feature flags (see
the AVX specification, version 007).  Add support for this new feature
flags word.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <tip-*@vger.kernel.org>
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H. Peter Anvin committed Jul 8, 2010
1 parent 24da9c2 commit bdc802d
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Showing 3 changed files with 21 additions and 4 deletions.
13 changes: 9 additions & 4 deletions arch/x86/include/asm/cpufeature.h
Original file line number Diff line number Diff line change
Expand Up @@ -6,7 +6,7 @@

#include <asm/required-features.h>

#define NCAPINTS 9 /* N 32-bit words worth of info */
#define NCAPINTS 10 /* N 32-bit words worth of info */

/*
* Note: If the comment begins with a quoted string, that string is used
Expand Down Expand Up @@ -159,14 +159,14 @@

/*
* Auxiliary flags: Linux defined - For features scattered in various
* CPUID levels like 0x6, 0xA etc
* CPUID levels like 0x6, 0xA etc, word 7
*/
#define X86_FEATURE_IDA (7*32+ 0) /* Intel Dynamic Acceleration */
#define X86_FEATURE_ARAT (7*32+ 1) /* Always Running APIC Timer */
#define X86_FEATURE_CPB (7*32+ 2) /* AMD Core Performance Boost */
#define X86_FEATURE_EPB (7*32+ 3) /* IA32_ENERGY_PERF_BIAS support */

/* Virtualization flags: Linux defined */
/* Virtualization flags: Linux defined, word 8 */
#define X86_FEATURE_TPR_SHADOW (8*32+ 0) /* Intel TPR Shadow */
#define X86_FEATURE_VNMI (8*32+ 1) /* Intel Virtual NMI */
#define X86_FEATURE_FLEXPRIORITY (8*32+ 2) /* Intel FlexPriority */
Expand All @@ -177,6 +177,9 @@
#define X86_FEATURE_SVML (8*32+7) /* "svm_lock" AMD SVM locking MSR */
#define X86_FEATURE_NRIPS (8*32+8) /* "nrip_save" AMD SVM next_rip save */

/* Intel-defined CPU features, CPUID level 0x00000007:0 (ebx), word 9 */
#define X86_FEATURE_FSGSBASE (9*32+0) /* {RD/WR}{FS/GS}BASE instructions*/

#if defined(__KERNEL__) && !defined(__ASSEMBLY__)

#include <asm/asm.h>
Expand All @@ -197,7 +200,9 @@ extern const char * const x86_power_flags[32];
(((bit)>>5)==4 && (1UL<<((bit)&31) & REQUIRED_MASK4)) || \
(((bit)>>5)==5 && (1UL<<((bit)&31) & REQUIRED_MASK5)) || \
(((bit)>>5)==6 && (1UL<<((bit)&31) & REQUIRED_MASK6)) || \
(((bit)>>5)==7 && (1UL<<((bit)&31) & REQUIRED_MASK7)) ) \
(((bit)>>5)==7 && (1UL<<((bit)&31) & REQUIRED_MASK7)) || \
(((bit)>>5)==8 && (1UL<<((bit)&31) & REQUIRED_MASK8)) || \
(((bit)>>5)==9 && (1UL<<((bit)&31) & REQUIRED_MASK9)) ) \
? 1 : \
test_cpu_cap(c, bit))

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2 changes: 2 additions & 0 deletions arch/x86/include/asm/required-features.h
Original file line number Diff line number Diff line change
Expand Up @@ -84,5 +84,7 @@
#define REQUIRED_MASK5 0
#define REQUIRED_MASK6 0
#define REQUIRED_MASK7 0
#define REQUIRED_MASK8 0
#define REQUIRED_MASK9 0

#endif /* _ASM_X86_REQUIRED_FEATURES_H */
10 changes: 10 additions & 0 deletions arch/x86/kernel/cpu/common.c
Original file line number Diff line number Diff line change
Expand Up @@ -551,6 +551,16 @@ static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
c->x86_capability[4] = excap;
}

/* Additional Intel-defined flags: level 0x00000007 */
if (c->cpuid_level >= 0x00000007) {
u32 eax, ebx, ecx, edx;

cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);

if (eax > 0)
c->x86_capability[9] = ebx;
}

/* AMD-defined flags: level 0x80000001 */
xlvl = cpuid_eax(0x80000000);
c->extended_cpuid_level = xlvl;
Expand Down

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