X86: Introduce HW-Pstate scattered cpuid feature

It is rather similar to CPB (boot capability) feature
and exists since fam10h (can be looked up in AMD's BKDG).

The feature is needed for powernow-k8 to cleanup init functions and to
provide proper autoloading matching with the new x86cpu modalias
feature.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Borislav Petkov <bp@amd64.org>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

arch/x86/include/asm/cpufeature.h

@@ -176,6 +176,7 @@
 #define X86_FEATURE_PLN		(7*32+ 5) /* Intel Power Limit Notification */
 #define X86_FEATURE_PTS		(7*32+ 6) /* Intel Package Thermal Status */
 #define X86_FEATURE_DTS		(7*32+ 7) /* Digital Thermal Sensor */
+#define X86_FEATURE_HW_PSTATE	(7*32+ 8) /* AMD HW-PState */
 
 /* Virtualization flags: Linux defined, word 8 */
 #define X86_FEATURE_TPR_SHADOW  (8*32+ 0) /* Intel TPR Shadow */

arch/x86/kernel/cpu/scattered.c

@@ -40,6 +40,7 @@ void __cpuinit init_scattered_cpuid_features(struct cpuinfo_x86 *c)
 		{ X86_FEATURE_EPB,		CR_ECX, 3, 0x00000006, 0 },
 		{ X86_FEATURE_XSAVEOPT,		CR_EAX,	0, 0x0000000d, 1 },
 		{ X86_FEATURE_CPB,		CR_EDX, 9, 0x80000007, 0 },
+		{ X86_FEATURE_HW_PSTATE,	CR_EDX, 7, 0x80000007, 0 },
 		{ X86_FEATURE_NPT,		CR_EDX, 0, 0x8000000a, 0 },
 		{ X86_FEATURE_LBRV,		CR_EDX, 1, 0x8000000a, 0 },
 		{ X86_FEATURE_SVML,		CR_EDX, 2, 0x8000000a, 0 },