1 files changed, 27 insertions, 23 deletions

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 65e20c97e04b..b5375b9497b3 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -133,26 +133,6 @@ static uint32_t  __init ms_hyperv_platform(void)
         return 0;
 }
 
-static u64 read_hv_clock(struct clocksource *arg)
-{
-        u64 current_tick;
-        /*
-         * Read the partition counter to get the current tick count. This count
-         * is set to 0 when the partition is created and is incremented in
-         * 100 nanosecond units.
-         */
-        rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
-        return current_tick;
-}
-
-static struct clocksource hyperv_cs = {
-        .name           = "hyperv_clocksource",
-        .rating         = 400, /* use this when running on Hyperv*/
-        .read           = read_hv_clock,
-        .mask           = CLOCKSOURCE_MASK(64),
-        .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
 static unsigned char hv_get_nmi_reason(void)
 {
         return 0;
@@ -180,6 +160,11 @@ static int hv_nmi_unknown(unsigned int val, struct pt_regs *regs)
 
 static void __init ms_hyperv_init_platform(void)
 {
+        int hv_host_info_eax;
+        int hv_host_info_ebx;
+        int hv_host_info_ecx;
+        int hv_host_info_edx;
+
         /*
          * Extract the features and hints
          */
@@ -190,6 +175,21 @@ static void __init ms_hyperv_init_platform(void)
         pr_info("HyperV: features 0x%x, hints 0x%x\n",
                 ms_hyperv.features, ms_hyperv.hints);
 
+        /*
+         * Extract host information.
+         */
+        if (cpuid_eax(HVCPUID_VENDOR_MAXFUNCTION) >= HVCPUID_VERSION) {
+                hv_host_info_eax = cpuid_eax(HVCPUID_VERSION);
+                hv_host_info_ebx = cpuid_ebx(HVCPUID_VERSION);
+                hv_host_info_ecx = cpuid_ecx(HVCPUID_VERSION);
+                hv_host_info_edx = cpuid_edx(HVCPUID_VERSION);
+
+                pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d\n",
+                        hv_host_info_eax, hv_host_info_ebx >> 16,
+                        hv_host_info_ebx & 0xFFFF, hv_host_info_ecx,
+                        hv_host_info_edx >> 24, hv_host_info_edx & 0xFFFFFF);
+        }
+
 #ifdef CONFIG_X86_LOCAL_APIC
         if (ms_hyperv.features & HV_X64_MSR_APIC_FREQUENCY_AVAILABLE) {
                 /*
@@ -208,9 +208,6 @@ static void __init ms_hyperv_init_platform(void)
                              "hv_nmi_unknown");
 #endif
 
-        if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE)
-                clocksource_register_hz(&hyperv_cs, NSEC_PER_SEC/100);
-
 #ifdef CONFIG_X86_IO_APIC
         no_timer_check = 1;
 #endif
@@ -227,6 +224,13 @@ static void __init ms_hyperv_init_platform(void)
          */
         if (efi_enabled(EFI_BOOT))
                 x86_platform.get_nmi_reason = hv_get_nmi_reason;
+
+#if IS_ENABLED(CONFIG_HYPERV)
+        /*
+         * Setup the hook to get control post apic initialization.
+         */
+        x86_platform.apic_post_init = hyperv_init;
+#endif
 }
 
 const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = {