1 files changed, 32 insertions, 29 deletions

diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c
index 141dce3c6810..968f40101883 100644
--- a/arch/powerpc/kvm/emulate.c
+++ b/arch/powerpc/kvm/emulate.c
@@ -13,6 +13,7 @@
  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  *
  * Copyright IBM Corp. 2007
+ * Copyright 2011 Freescale Semiconductor, Inc.
  *
  * Authors: Hollis Blanchard <hollisb@us.ibm.com>
  */
@@ -69,54 +70,55 @@
 #define OP_STH  44
 #define OP_STHU 45
 
-#ifdef CONFIG_PPC_BOOK3S
-static int kvmppc_dec_enabled(struct kvm_vcpu *vcpu)
-{
-        return 1;
-}
-#else
-static int kvmppc_dec_enabled(struct kvm_vcpu *vcpu)
-{
-        return vcpu->arch.tcr & TCR_DIE;
-}
-#endif
-
 void kvmppc_emulate_dec(struct kvm_vcpu *vcpu)
 {
         unsigned long dec_nsec;
+        unsigned long long dec_time;
 
         pr_debug("mtDEC: %x\n", vcpu->arch.dec);
+        hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
+
 #ifdef CONFIG_PPC_BOOK3S
         /* mtdec lowers the interrupt line when positive. */
         kvmppc_core_dequeue_dec(vcpu);
 
         /* POWER4+ triggers a dec interrupt if the value is < 0 */
         if (vcpu->arch.dec & 0x80000000) {
-                hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
                 kvmppc_core_queue_dec(vcpu);
                 return;
         }
 #endif
-        if (kvmppc_dec_enabled(vcpu)) {
-                /* The decrementer ticks at the same rate as the timebase, so
-                 * that's how we convert the guest DEC value to the number of
-                 * host ticks. */
-
-                hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
-                dec_nsec = vcpu->arch.dec;
-                dec_nsec *= 1000;
-                dec_nsec /= tb_ticks_per_usec;
-                hrtimer_start(&vcpu->arch.dec_timer, ktime_set(0, dec_nsec),
-                              HRTIMER_MODE_REL);
-                vcpu->arch.dec_jiffies = get_tb();
-        } else {
-                hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
-        }
+
+#ifdef CONFIG_BOOKE
+        /* On BOOKE, DEC = 0 is as good as decrementer not enabled */
+        if (vcpu->arch.dec == 0)
+                return;
+#endif
+
+        /*
+         * The decrementer ticks at the same rate as the timebase, so
+         * that's how we convert the guest DEC value to the number of
+         * host ticks.
+         */
+
+        dec_time = vcpu->arch.dec;
+        dec_time *= 1000;
+        do_div(dec_time, tb_ticks_per_usec);
+        dec_nsec = do_div(dec_time, NSEC_PER_SEC);
+        hrtimer_start(&vcpu->arch.dec_timer,
+                ktime_set(dec_time, dec_nsec), HRTIMER_MODE_REL);
+        vcpu->arch.dec_jiffies = get_tb();
 }
 
 u32 kvmppc_get_dec(struct kvm_vcpu *vcpu, u64 tb)
 {
         u64 jd = tb - vcpu->arch.dec_jiffies;
+
+#ifdef CONFIG_BOOKE
+        if (vcpu->arch.dec < jd)
+                return 0;
+#endif
+
         return vcpu->arch.dec - jd;
 }
 
@@ -159,7 +161,8 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
         case OP_TRAP_64:
                 kvmppc_core_queue_program(vcpu, SRR1_PROGTRAP);
 #else
-                kvmppc_core_queue_program(vcpu, vcpu->arch.esr | ESR_PTR);
+                kvmppc_core_queue_program(vcpu,
+                                          vcpu->arch.shared->esr | ESR_PTR);
 #endif
                 advance = 0;
                 break;