6 files changed, 91 insertions, 4 deletions

diff --git a/arch/x86/include/asm/hyperv.h b/arch/x86/include/asm/hyperv.h
index e153a2b3889a..46040473e122 100644
--- a/arch/x86/include/asm/hyperv.h
+++ b/arch/x86/include/asm/hyperv.h
@@ -14,6 +14,9 @@
 #define HYPERV_CPUID_ENLIGHTMENT_INFO           0x40000004
 #define HYPERV_CPUID_IMPLEMENT_LIMITS           0x40000005
 
+#define HYPERV_HYPERVISOR_PRESENT_BIT           0x80000000
+#define HYPERV_CPUID_MIN                        0x40000005
+
 /*
  * Feature identification. EAX indicates which features are available
  * to the partition based upon the current partition privileges.
@@ -129,6 +132,9 @@
 /* MSR used to provide vcpu index */
 #define HV_X64_MSR_VP_INDEX                     0x40000002
 
+/* MSR used to read the per-partition time reference counter */
+#define HV_X64_MSR_TIME_REF_COUNT               0x40000020
+
 /* Define the virtual APIC registers */
 #define HV_X64_MSR_EOI                          0x40000070
 #define HV_X64_MSR_ICR                          0x40000071
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
new file mode 100644
index 000000000000..6cd8101d1344
--- /dev/null
+++ b/arch/x86/include/asm/mshyperv.h
@@ -0,0 +1,7 @@
+#ifndef ASM_X86__MSHYPER_H
+#define ASM_X86__MSHYPER_H
+
+int ms_hyperv_platform(void);
+void __cpuinit ms_hyperv_set_feature_bits(struct cpuinfo_x86 *c);
+
+#endif
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index b753ea59703a..597c041bd124 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -114,6 +114,8 @@ struct cpuinfo_x86 {
         u16                     cpu_index;
 #endif
         unsigned int            x86_hyper_vendor;
+        /* The layout of this field is hypervisor specific */
+        unsigned int            x86_hyper_features;
 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
 
 #define X86_VENDOR_INTEL        0
@@ -129,6 +131,7 @@ struct cpuinfo_x86 {
 
 #define X86_HYPER_VENDOR_NONE  0
 #define X86_HYPER_VENDOR_VMWARE 1
+#define X86_HYPER_VENDOR_MSFT   2
 
 /*
  * capabilities of CPUs
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index c202b62f3671..3a785da34b6f 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -14,7 +14,7 @@ CFLAGS_common.o		:= $(nostackp)
 
 obj-y                   := intel_cacheinfo.o addon_cpuid_features.o
 obj-y                   += proc.o capflags.o powerflags.o common.o
-obj-y                   += vmware.o hypervisor.o sched.o
+obj-y                   += vmware.o hypervisor.o sched.o mshyperv.o
 
 obj-$(CONFIG_X86_32)    += bugs.o cmpxchg.o
 obj-$(CONFIG_X86_64)    += bugs_64.o
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
index 08be922de33a..de3f4e0ce8eb 100644
--- a/arch/x86/kernel/cpu/hypervisor.c
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -23,6 +23,7 @@
 
 #include <asm/processor.h>
 #include <asm/vmware.h>
+#include <asm/mshyperv.h>
 #include <asm/hypervisor.h>
 
 static inline void __cpuinit
@@ -30,6 +31,8 @@ detect_hypervisor_vendor(struct cpuinfo_x86 *c)
 {
         if (vmware_platform())
                 c->x86_hyper_vendor = X86_HYPER_VENDOR_VMWARE;
+        else if (ms_hyperv_platform())
+                c->x86_hyper_vendor = X86_HYPER_VENDOR_MSFT;
         else
                 c->x86_hyper_vendor = X86_HYPER_VENDOR_NONE;
 }
@@ -37,10 +40,11 @@ detect_hypervisor_vendor(struct cpuinfo_x86 *c)
 static inline void __cpuinit
 hypervisor_set_feature_bits(struct cpuinfo_x86 *c)
 {
-        if (boot_cpu_data.x86_hyper_vendor == X86_HYPER_VENDOR_VMWARE) {
+        if (boot_cpu_data.x86_hyper_vendor == X86_HYPER_VENDOR_VMWARE)
                 vmware_set_feature_bits(c);
-                return;
-        }
+        else if (boot_cpu_data.x86_hyper_vendor == X86_HYPER_VENDOR_MSFT)
+                ms_hyperv_set_feature_bits(c);
+        return;
 }
 
 void __cpuinit init_hypervisor(struct cpuinfo_x86 *c)
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
new file mode 100644
index 000000000000..2443b61cdb17
--- /dev/null
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -0,0 +1,67 @@
+/*
+ * HyperV  Detection code.
+ *
+ * Copyright (C) 2010, Novell, Inc.
+ * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <linux/types.h>
+#include <asm/processor.h>
+#include <asm/hyperv.h>
+#include <asm/mshyperv.h>
+
+
+int ms_hyperv_platform(void)
+{
+        u32 eax, ebx, ecx, edx;
+        char hyp_signature[13];
+
+        cpuid(1, &eax, &ebx, &ecx, &edx);
+        if (!(ecx & HYPERV_HYPERVISOR_PRESENT_BIT))
+                return 0;
+
+        cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS, &eax, &ebx, &ecx, &edx);
+        *(u32 *)(hyp_signature + 0) = ebx;
+        *(u32 *)(hyp_signature + 4) = ecx;
+        *(u32 *)(hyp_signature + 8) = edx;
+
+        if ((eax < HYPERV_CPUID_MIN) || (memcmp("Microsoft Hv", hyp_signature, 12)))
+                return 0;
+        return 1;
+}
+
+void __cpuinit ms_hyperv_set_feature_bits(struct cpuinfo_x86 *c)
+{
+        u32 eax, ebx, ecx, edx;
+
+        c->x86_hyper_features = 0;
+        /*
+         * Extract the features, recommendations etc.
+         * The first 9 bits will be used to track hypervisor features.
+         * The next 6 bits will be used to track the hypervisor
+         * recommendations.
+         */
+        cpuid(HYPERV_CPUID_FEATURES, &eax, &ebx, &ecx, &edx);
+        c->x86_hyper_features |= (eax & 0x1ff);
+
+        cpuid(HYPERV_CPUID_ENLIGHTMENT_INFO, &eax, &ebx, &ecx, &edx);
+        c->x86_hyper_features |= ((eax & 0x3f) << 9);
+        printk(KERN_INFO "Detected HyperV with features: %x\n",
+                c->x86_hyper_features);
+}