KVM: PPC: booke: standard PPC floating point support
e500mc has a normal PPC FPU, rather than SPE which is found
on e500v1/v2.
Based on code from Liu Yu <yu.liu@freescale.com>.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/powerpc/kvm/booke.h b/arch/powerpc/kvm/booke.h
index d53bcf2..62c4fe5 100644
--- a/arch/powerpc/kvm/booke.h
+++ b/arch/powerpc/kvm/booke.h
@@ -23,6 +23,7 @@
#include <linux/types.h>
#include <linux/kvm_host.h>
#include <asm/kvm_ppc.h>
+#include <asm/switch_to.h>
#include "timing.h"
/* interrupt priortity ordering */
@@ -96,4 +97,34 @@
void kvmppc_set_pending_interrupt(struct kvm_vcpu *vcpu, enum int_class type);
+/*
+ * Load up guest vcpu FP state if it's needed.
+ * It also set the MSR_FP in thread so that host know
+ * we're holding FPU, and then host can help to save
+ * guest vcpu FP state if other threads require to use FPU.
+ * This simulates an FP unavailable fault.
+ *
+ * It requires to be called with preemption disabled.
+ */
+static inline void kvmppc_load_guest_fp(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_PPC_FPU
+ if (vcpu->fpu_active && !(current->thread.regs->msr & MSR_FP)) {
+ load_up_fpu();
+ current->thread.regs->msr |= MSR_FP;
+ }
+#endif
+}
+
+/*
+ * Save guest vcpu FP state into thread.
+ * It requires to be called with preemption disabled.
+ */
+static inline void kvmppc_save_guest_fp(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_PPC_FPU
+ if (vcpu->fpu_active && (current->thread.regs->msr & MSR_FP))
+ giveup_fpu(current);
+#endif
+}
#endif /* __KVM_BOOKE_H__ */