This patch enables arm64 lazy fp/simd switch, similar to arm described in
second patch. Change from previous version - restore function is moved to
host.
Signed-off-by: Mario Smarduch <m.smard...@samsung.com>
---
arch/arm64/include/asm/kvm_host.h | 2 +-
arch/arm64/kernel/asm-offsets.c | 1 +
arch/arm64/kvm/hyp.S | 37 +++++++++++++++++++++++++++++++------
3 files changed, 33 insertions(+), 7 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h
b/arch/arm64/include/asm/kvm_host.h
index 26a2347..dcecf92 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -251,11 +251,11 @@ static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {}
static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
-static inline void kvm_restore_host_vfp_state(struct kvm_vcpu *vcpu) {}
void kvm_arm_init_debug(void);
void kvm_arm_setup_debug(struct kvm_vcpu *vcpu);
void kvm_arm_clear_debug(struct kvm_vcpu *vcpu);
void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu);
+void kvm_restore_host_vfp_state(struct kvm_vcpu *vcpu);
#endif /* __ARM64_KVM_HOST_H__ */
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 8d89cf8..c9c5242 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -124,6 +124,7 @@ int main(void)
DEFINE(VCPU_HCR_EL2, offsetof(struct kvm_vcpu, arch.hcr_el2));
DEFINE(VCPU_MDCR_EL2, offsetof(struct kvm_vcpu, arch.mdcr_el2));
DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines));
+ DEFINE(VCPU_VFP_DIRTY, offsetof(struct kvm_vcpu, arch.vfp_dirty));
DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu,
arch.host_cpu_context));
DEFINE(VCPU_HOST_DEBUG_STATE, offsetof(struct kvm_vcpu,
arch.host_debug_state));
DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu,
arch.timer_cpu.cntv_ctl));
diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index e583613..ed2c4cf 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -36,6 +36,28 @@
#define CPU_SYSREG_OFFSET(x) (CPU_SYSREGS + 8*x)
.text
+
+/**
+ * void kvm_restore_host_vfp_state(struct vcpu *vcpu) - Executes lazy
+ * fp/simd switch, saves the guest, restores host. Called from host
+ * mode, placed outside of hyp section.
+ */
+ENTRY(kvm_restore_host_vfp_state)
+ push xzr, lr
+
+ add x2, x0, #VCPU_CONTEXT
+ mov w3, #0
+ strb w3, [x0, #VCPU_VFP_DIRTY]
+
+ bl __save_fpsimd
+
+ ldr x2, [x0, #VCPU_HOST_CONTEXT]
+ bl __restore_fpsimd
+
+ pop xzr, lr
+ ret
+ENDPROC(kvm_restore_host_vfp_state)
+
.pushsection .hyp.text, "ax"
.align PAGE_SHIFT
@@ -482,7 +504,11 @@
99:
msr hcr_el2, x2
mov x2, #CPTR_EL2_TTA
+
+ ldrb w3, [x0, #VCPU_VFP_DIRTY]
+ tbnz w3, #0, 98f
orr x2, x2, #CPTR_EL2_TFP
+98:
msr cptr_el2, x2
mov x2, #(1 << 15) // Trap CP15 Cr=15
@@ -669,14 +695,12 @@ __restore_debug:
ret
__save_fpsimd:
- skip_fpsimd_state x3, 1f
save_fpsimd
-1: ret
+ ret
__restore_fpsimd:
- skip_fpsimd_state x3, 1f
restore_fpsimd
-1: ret
+ ret
switch_to_guest_fpsimd:
push x4, lr
@@ -688,6 +712,9 @@ switch_to_guest_fpsimd:
mrs x0, tpidr_el2
+ mov w2, #1
+ strb w2, [x0, #VCPU_VFP_DIRTY]
+
ldr x2, [x0, #VCPU_HOST_CONTEXT]
kern_hyp_va x2
bl __save_fpsimd
@@ -763,7 +790,6 @@ __kvm_vcpu_return:
add x2, x0, #VCPU_CONTEXT
save_guest_regs
- bl __save_fpsimd
bl __save_sysregs
skip_debug_state x3, 1f
@@ -784,7 +810,6 @@ __kvm_vcpu_return:
kern_hyp_va x2
bl __restore_sysregs
- bl __restore_fpsimd
/* Clear FPSIMD and Trace trapping */
msr cptr_el2, xzr
--
1.9.1
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