Commit-ID: 2167ceabf34163727ca4e283c0f030e3960932e5 Gitweb: http://git.kernel.org/tip/2167ceabf34163727ca4e283c0f030e3960932e5 Author: Wan Zongshun <Vincent.Wan@xxxxxxx> AuthorDate: Fri, 30 Oct 2015 13:11:39 +0100 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Sun, 1 Nov 2015 11:26:23 +0100 x86/cpu: Add CLZERO detection AMD Fam17h processors introduce support for the CLZERO instruction. It zeroes out the 64 byte cache line specified in RAX. Add the bit here to allow /proc/cpuinfo to list the feature. Boris: we're adding this as a separate ->x86_capability leaf because CPUID_80000008_EBX is going to contain more feature bits and it will fill out with time. Signed-off-by: Wan Zongshun <Vincent.Wan@xxxxxxx> Signed-off-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@xxxxxxx> [ Wrap code in patch form, fix comments. ] Signed-off-by: Borislav Petkov <bp@xxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Huang Rui <ray.huang@xxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Link: http://lkml.kernel.org/r/1446207099-24948-4-git-send-email-bp@xxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/include/asm/cpufeature.h | 5 ++++- arch/x86/kernel/cpu/common.c | 1 + 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 9727b3b..e4f8010 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -12,7 +12,7 @@ #include <asm/disabled-features.h> #endif -#define NCAPINTS 13 /* N 32-bit words worth of info */ +#define NCAPINTS 14 /* N 32-bit words worth of info */ #define NBUGINTS 1 /* N 32-bit bug flags */ /* @@ -255,6 +255,9 @@ /* Intel-defined CPU QoS Sub-leaf, CPUID level 0x0000000F:1 (edx), word 12 */ #define X86_FEATURE_CQM_OCCUP_LLC (12*32+ 0) /* LLC occupancy monitoring if 1 */ +/* AMD-defined CPU features, CPUID level 0x80000008 (ebx), word 13 */ +#define X86_FEATURE_CLZERO (13*32+0) /* CLZERO instruction */ + /* * BUG word(s) */ diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index de22ea7..4ddd780 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -670,6 +670,7 @@ void get_cpu_cap(struct cpuinfo_x86 *c) c->x86_virt_bits = (eax >> 8) & 0xff; c->x86_phys_bits = eax & 0xff; + c->x86_capability[13] = cpuid_ebx(0x80000008); } #ifdef CONFIG_X86_32 else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36)) -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html