ARM: KVM: Add VFP save/restore
This is almost a copy/paste of the existing version, with a couple
of subtle differences:
- Only write to FPEXC once on the save path
- Add an isb when enabling VFP access
The patch also defines a few sysreg accessors and a __vfp_enabled
predicate that test the VFP trapping state.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/arch/arm/kvm/hyp/hyp.h b/arch/arm/kvm/hyp/hyp.h
index 7eb1c21..dce0f73 100644
--- a/arch/arm/kvm/hyp/hyp.h
+++ b/arch/arm/kvm/hyp/hyp.h
@@ -21,6 +21,7 @@
#include <linux/compiler.h>
#include <linux/kvm_host.h>
#include <asm/kvm_mmu.h>
+#include <asm/vfp.h>
#define __hyp_text __section(.hyp.text) notrace
@@ -31,6 +32,8 @@
"mrc", "mcr", __stringify(p15, Op1, %0, CRn, CRm, Op2), u32
#define __ACCESS_CP15_64(Op1, CRm) \
"mrrc", "mcrr", __stringify(p15, Op1, %Q0, %R0, CRm), u64
+#define __ACCESS_VFP(CRn) \
+ "mrc", "mcr", __stringify(p10, 7, %0, CRn, cr0, 0), u32
#define __write_sysreg(v, r, w, c, t) asm volatile(w " " c : : "r" ((t)(v)))
#define write_sysreg(v, ...) __write_sysreg(v, __VA_ARGS__)
@@ -53,6 +56,7 @@
#define VMPIDR __ACCESS_CP15(c0, 4, c0, 5)
#define SCTLR __ACCESS_CP15(c1, 0, c0, 0)
#define CPACR __ACCESS_CP15(c1, 0, c0, 2)
+#define HCPTR __ACCESS_CP15(c1, 4, c1, 2)
#define TTBCR __ACCESS_CP15(c2, 0, c0, 2)
#define DACR __ACCESS_CP15(c3, 0, c0, 0)
#define DFSR __ACCESS_CP15(c5, 0, c0, 0)
@@ -77,6 +81,8 @@
#define CNTV_CTL __ACCESS_CP15(c14, 0, c3, 1)
#define CNTHCTL __ACCESS_CP15(c14, 4, c1, 0)
+#define VFP_FPEXC __ACCESS_VFP(FPEXC)
+
void __timer_save_state(struct kvm_vcpu *vcpu);
void __timer_restore_state(struct kvm_vcpu *vcpu);
@@ -86,4 +92,11 @@
void __sysreg_save_state(struct kvm_cpu_context *ctxt);
void __sysreg_restore_state(struct kvm_cpu_context *ctxt);
+void asmlinkage __vfp_save_state(struct vfp_hard_struct *vfp);
+void asmlinkage __vfp_restore_state(struct vfp_hard_struct *vfp);
+static inline bool __vfp_enabled(void)
+{
+ return !(read_sysreg(HCPTR) & (HCPTR_TCP(11) | HCPTR_TCP(10)));
+}
+
#endif /* __ARM_KVM_HYP_H__ */