Add some very minimal architected timer related infrastructure.
For the moment, we just provide empty structures, and enable/disable
access to the physical timer across world switch.
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm/include/asm/kvm_arch_timer.h | 27 +++++++++++++++++++++++++++
arch/arm/include/asm/kvm_host.h | 5 +++++
arch/arm/kvm/interrupts.S | 23 ++++++++++++++++++++++-
3 files changed, 54 insertions(+), 1 deletion(-)
create mode 100644 arch/arm/include/asm/kvm_arch_timer.h
diff --git a/arch/arm/include/asm/kvm_arch_timer.h b/arch/arm/include/asm/kvm_arch_timer.h
new file mode 100644
index 0000000..491e336
--- /dev/null
+++ b/arch/arm/include/asm/kvm_arch_timer.h
@@ -0,0 +1,27 @@
+#ifndef __ASM_ARM_KVM_ARCH_TIMER_H
+#define __ASM_ARM_KVM_ARCH_TIMER_H
+
+struct arch_timer_kvm {
+};
+
+struct arch_timer_cpu {
+};
+
+#ifndef CONFIG_KVM_ARM_TIMER
+static inline int kvm_timer_hyp_init(void)
+{
+ return 0;
+};
+
+static inline int kvm_timer_init(struct kvm *kvm)
+{
+ return 0;
+}
+
+static inline void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_sync_to_cpu(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_sync_from_cpu(struct kvm_vcpu *vcpu) {}
+static inline void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) {}
+#endif
+
+#endif
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 3b289b8..2e7364c 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -25,6 +25,7 @@
#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
#include <asm/kvm_vgic.h>
+#include <asm/kvm_arch_timer.h>
/* We don't currently support large pages. */
#define KVM_HPAGE_GFN_SHIFT(x) 0
@@ -50,6 +51,9 @@ struct kvm_arch {
/* Interrupt controller */
struct vgic_dist vgic;
+
+ /* Timer */
+ struct arch_timer_kvm timer;
};
#define EXCEPTION_NONE 0
@@ -133,6 +137,7 @@ struct kvm_vcpu_arch {
/* VGIC state */
struct vgic_cpu vgic_cpu;
+ struct arch_timer_cpu timer_cpu;
};
struct kvm_vm_stat {
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 40c3c9f..1b03b79 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -342,7 +342,26 @@ ENDPROC(__kvm_flush_vm_context)
2:
#endif
.endm
-
+
+#define PL1P_ENABLE 3
+#define PL1P_DISABLE 3
+
+.macro save_timer_state vcpup
+ @ Allow physical timer access for the host
+ mrc p15, 4, r2, c14, c1, 0 @ CNTHCTL
+ orr r2, r2, #PL1P_ENABLE
+ mcr p15, 4, r2, c14, c1, 0 @ CNTHCTL
+.endm
+
+.macro restore_timer_state vcpup
+ @ Disallow physical timer access for the guest
+ mrc p15, 4, r2, c14, c1, 0 @ CNTHCTL
+ bic r2, r2, #PL1P_DISABLE
+ mcr p15, 4, r2, c14, c1, 0 @ CNTHCTL
+
+ isb
+.endm
+
/* Configures the HSTR (Hyp System Trap Register) on entry/return
* (hardware reset value is 0) */
.macro set_hstr entry
@@ -401,6 +420,7 @@ ENTRY(__kvm_vcpu_run)
store_mode_state sp, fiq
restore_vgic_state r0
+ restore_timer_state r0
@ Store hardware CP15 state and load guest state
read_cp15_state
@@ -490,6 +510,7 @@ __kvm_vcpu_return:
read_cp15_state 1, r1
write_cp15_state
+ save_timer_state r1
save_vgic_state r1
load_mode_state sp, fiq
--
1.7.10.3
