commit a3e06bbe8445f57eb949e6474c5a9b30f24d2057
author Liu, Jinsong <jinsong.liu@intel.com> Thu Sep 22 16:55:52 2011 +0800
committer Avi Kivity <avi@redhat.com> Wed Oct 05 15:34:56 2011 +0200
tree fc6f43d1c4424a5bdab1e39fe1e29e8b3ca47ae3
parent b90dfb0419a79a90395e04fee3fbda3c12ba8237

KVM: emulate lapic tsc deadline timer for guest

This patch emulate lapic tsc deadline timer for guest:
Enumerate tsc deadline timer capability by CPUID;
Enable tsc deadline timer mode by lapic MMIO;
Start tsc deadline timer by WRMSR;

[jan: use do_div()]
[avi: fix for !irqchip_in_kernel()]
[marcelo: another fix for !irqchip_in_kernel()]

Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d51e407..cf26909 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -600,6 +600,8 @@
 static void update_cpuid(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpuid_entry2 *best;
+	struct kvm_lapic *apic = vcpu->arch.apic;
+	u32 timer_mode_mask;
 
 	best = kvm_find_cpuid_entry(vcpu, 1, 0);
 	if (!best)
@@ -611,6 +613,16 @@
 		if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE))
 			best->ecx |= bit(X86_FEATURE_OSXSAVE);
 	}
+
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+		best->function == 0x1) {
+		best->ecx |= bit(X86_FEATURE_TSC_DEADLINE_TIMER);
+		timer_mode_mask = 3 << 17;
+	} else
+		timer_mode_mask = 1 << 17;
+
+	if (apic)
+		apic->lapic_timer.timer_mode_mask = timer_mode_mask;
 }
 
 int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
@@ -826,6 +838,7 @@
 static unsigned num_msrs_to_save;
 
 static u32 emulated_msrs[] = {
+	MSR_IA32_TSCDEADLINE,
 	MSR_IA32_MISC_ENABLE,
 	MSR_IA32_MCG_STATUS,
 	MSR_IA32_MCG_CTL,
@@ -1001,7 +1014,7 @@
 	return ret;
 }
 
-static u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu)
+u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu)
 {
 	if (vcpu->arch.virtual_tsc_khz)
 		return vcpu->arch.virtual_tsc_khz;
@@ -1565,6 +1578,9 @@
 		break;
 	case APIC_BASE_MSR ... APIC_BASE_MSR + 0x3ff:
 		return kvm_x2apic_msr_write(vcpu, msr, data);
+	case MSR_IA32_TSCDEADLINE:
+		kvm_set_lapic_tscdeadline_msr(vcpu, data);
+		break;
 	case MSR_IA32_MISC_ENABLE:
 		vcpu->arch.ia32_misc_enable_msr = data;
 		break;
@@ -1894,6 +1910,9 @@
 	case APIC_BASE_MSR ... APIC_BASE_MSR + 0x3ff:
 		return kvm_x2apic_msr_read(vcpu, msr, pdata);
 		break;
+	case MSR_IA32_TSCDEADLINE:
+		data = kvm_get_lapic_tscdeadline_msr(vcpu);
+		break;
 	case MSR_IA32_MISC_ENABLE:
 		data = vcpu->arch.ia32_misc_enable_msr;
 		break;