KVM: ia64: Create inline function kvm_get_itc() to centralize ITC reading.

Move all reading of special register 'AR_ITC' into two functions, one
in the kernel and one in the VMM module. When running on SN2, base the
result on the RTC rather the system ITC, as the ITC isn't
synchronized.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index 14a3fab..ebbd995 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -68,6 +68,16 @@
 	{ NULL }
 };
 
+static unsigned long kvm_get_itc(struct kvm_vcpu *vcpu)
+{
+#if defined(CONFIG_IA64_SGI_SN2) || defined(CONFIG_IA64_GENERIC)
+	if (vcpu->kvm->arch.is_sn2)
+		return rtc_time();
+	else
+#endif
+		return ia64_getreg(_IA64_REG_AR_ITC);
+}
+
 static void kvm_flush_icache(unsigned long start, unsigned long len)
 {
 	int l;
@@ -457,7 +467,7 @@
 
 	if (irqchip_in_kernel(vcpu->kvm)) {
 
-		vcpu_now_itc = ia64_getreg(_IA64_REG_AR_ITC) + vcpu->arch.itc_offset;
+		vcpu_now_itc = kvm_get_itc(vcpu) + vcpu->arch.itc_offset;
 
 		if (time_after(vcpu_now_itc, vpd->itm)) {
 			vcpu->arch.timer_check = 1;
@@ -929,7 +939,7 @@
 	RESTORE_REGS(saved_gp);
 
 	vcpu->arch.irq_new_pending = 1;
-	vcpu->arch.itc_offset = regs->saved_itc - ia64_getreg(_IA64_REG_AR_ITC);
+	vcpu->arch.itc_offset = regs->saved_itc - kvm_get_itc(vcpu);
 	set_bit(KVM_REQ_RESUME, &vcpu->requests);
 
 	vcpu_put(vcpu);
@@ -1210,7 +1220,7 @@
 		regs->cr_iip = PALE_RESET_ENTRY;
 
 		/*Initialize itc offset for vcpus*/
-		itc_offset = 0UL - ia64_getreg(_IA64_REG_AR_ITC);
+		itc_offset = 0UL - kvm_get_itc(vcpu);
 		for (i = 0; i < kvm->arch.online_vcpus; i++) {
 			v = (struct kvm_vcpu *)((char *)vcpu +
 					sizeof(struct kvm_vcpu_data) * i);
@@ -1472,7 +1482,7 @@
 	}
 	for (i = 0; i < 4; i++)
 		regs->insvc[i] = vcpu->arch.insvc[i];
-	regs->saved_itc = vcpu->arch.itc_offset + ia64_getreg(_IA64_REG_AR_ITC);
+	regs->saved_itc = vcpu->arch.itc_offset + kvm_get_itc(vcpu);
 	SAVE_REGS(xtp);
 	SAVE_REGS(metaphysical_rr0);
 	SAVE_REGS(metaphysical_rr4);