x86/cpufeatures: Add FEATURE_ZEN

commit d1035d971829dcf80e8686ccde26f94b0a069472 upstream

Add a ZEN feature bit so family-dependent static_cpu_has() optimizations
can be built for ZEN.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 7dd1bba..8ae9132 100644 (file)
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -213,6 +213,8 @@
 #define X86_FEATURE_IBRS       ( 7*32+25) /* Indirect Branch Restricted Speculation */
 #define X86_FEATURE_IBPB       ( 7*32+26) /* Indirect Branch Prediction Barrier */
 #define X86_FEATURE_STIBP      ( 7*32+27) /* Single Thread Indirect Branch Predictors */
+#define X86_FEATURE_ZEN                ( 7*32+28) /* "" CPU is AMD family 0x17 (Zen) */
+
 
 /* Virtualization flags: Linux defined, word 8 */
 #define X86_FEATURE_TPR_SHADOW  ( 8*32+ 0) /* Intel TPR Shadow */

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 87f4a0d..9f61518 100644 (file)
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -715,6 +715,7 @@ static void init_amd_bd(struct cpuinfo_x86 *c)
 
 static void init_amd_zn(struct cpuinfo_x86 *c)
 {
+       set_cpu_cap(c, X86_FEATURE_ZEN);
        /*
         * Fix erratum 1076: CPB feature bit not being set in CPUID. It affects
         * all up to and including B1.