KVM: ia64: remove redundant kvm_get_exit_data() NULL tests
[linux-2.6.git] / arch / ia64 / kvm / kvm_fw.c
index a8ae52e..cb548ee 100644 (file)
@@ -21,6 +21,9 @@
 
 #include <linux/kvm_host.h>
 #include <linux/smp.h>
+#include <asm/sn/addrs.h>
+#include <asm/sn/clksupport.h>
+#include <asm/sn/shub_mmr.h>
 
 #include "vti.h"
 #include "misc.h"
@@ -72,7 +75,7 @@ static void set_pal_result(struct kvm_vcpu *vcpu,
        struct exit_ctl_data *p;
 
        p = kvm_get_exit_data(vcpu);
-       if (p && p->exit_reason == EXIT_REASON_PAL_CALL) {
+       if (p->exit_reason == EXIT_REASON_PAL_CALL) {
                p->u.pal_data.ret = result;
                return ;
        }
@@ -84,7 +87,7 @@ static void set_sal_result(struct kvm_vcpu *vcpu,
        struct exit_ctl_data *p;
 
        p = kvm_get_exit_data(vcpu);
-       if (p && p->exit_reason == EXIT_REASON_SAL_CALL) {
+       if (p->exit_reason == EXIT_REASON_SAL_CALL) {
                p->u.sal_data.ret = result;
                return ;
        }
@@ -188,12 +191,35 @@ static struct ia64_pal_retval pal_freq_base(struct kvm_vcpu *vcpu)
        return result;
 }
 
-static struct ia64_pal_retval pal_freq_ratios(struct kvm_vcpu *vcpu)
+/*
+ * On the SGI SN2, the ITC isn't stable. Emulation backed by the SN2
+ * RTC is used instead. This function patches the ratios from SAL
+ * to match the RTC before providing them to the guest.
+ */
+static void sn2_patch_itc_freq_ratios(struct ia64_pal_retval *result)
 {
+       struct pal_freq_ratio *ratio;
+       unsigned long sal_freq, sal_drift, factor;
+
+       result->status = ia64_sal_freq_base(SAL_FREQ_BASE_PLATFORM,
+                                           &sal_freq, &sal_drift);
+       ratio = (struct pal_freq_ratio *)&result->v2;
+       factor = ((sal_freq * 3) + (sn_rtc_cycles_per_second / 2)) /
+               sn_rtc_cycles_per_second;
 
+       ratio->num = 3;
+       ratio->den = factor;
+}
+
+static struct ia64_pal_retval pal_freq_ratios(struct kvm_vcpu *vcpu)
+{
        struct ia64_pal_retval result;
 
        PAL_CALL(result, PAL_FREQ_RATIOS, 0, 0, 0);
+
+       if (vcpu->kvm->arch.is_sn2)
+               sn2_patch_itc_freq_ratios(&result);
+
        return result;
 }
 
@@ -296,7 +322,7 @@ static  u64 kvm_get_pal_call_index(struct kvm_vcpu *vcpu)
        struct exit_ctl_data *p;
 
        p = kvm_get_exit_data(vcpu);
-       if (p && (p->exit_reason == EXIT_REASON_PAL_CALL))
+       if (p->exit_reason == EXIT_REASON_PAL_CALL)
                index = p->u.pal_data.gr28;
 
        return index;
@@ -620,18 +646,16 @@ static void kvm_get_sal_call_data(struct kvm_vcpu *vcpu, u64 *in0, u64 *in1,
 
        p = kvm_get_exit_data(vcpu);
 
-       if (p) {
-               if (p->exit_reason == EXIT_REASON_SAL_CALL) {
-                       *in0 = p->u.sal_data.in0;
-                       *in1 = p->u.sal_data.in1;
-                       *in2 = p->u.sal_data.in2;
-                       *in3 = p->u.sal_data.in3;
-                       *in4 = p->u.sal_data.in4;
-                       *in5 = p->u.sal_data.in5;
-                       *in6 = p->u.sal_data.in6;
-                       *in7 = p->u.sal_data.in7;
-                       return ;
-               }
+       if (p->exit_reason == EXIT_REASON_SAL_CALL) {
+               *in0 = p->u.sal_data.in0;
+               *in1 = p->u.sal_data.in1;
+               *in2 = p->u.sal_data.in2;
+               *in3 = p->u.sal_data.in3;
+               *in4 = p->u.sal_data.in4;
+               *in5 = p->u.sal_data.in5;
+               *in6 = p->u.sal_data.in6;
+               *in7 = p->u.sal_data.in7;
+               return ;
        }
        *in0 = 0;
 }