MIPS: KVM: Add count frequency KVM register

Expose the KVM guest CP0_Count frequency to userland via a new
KVM_REG_MIPS_COUNT_HZ register accessible with the KVM_{GET,SET}_ONE_REG
ioctls.

When the frequency is altered the bias is adjusted such that the guest
CP0_Count doesn't jump discontinuously or lose any timer interrupts.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: David Daney <david.daney@cavium.com>
Cc: Sanjay Lal <sanjayl@kymasys.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
James Hogan
2014-05-29 10:16:38 +01:00
committed by Paolo Bonzini
parent f82393426a
commit f74a8e224e
5 changed files with 65 additions and 0 deletions

View File

@@ -720,6 +720,7 @@ void kvm_mips_write_compare(struct kvm_vcpu *vcpu, uint32_t compare);
void kvm_mips_init_count(struct kvm_vcpu *vcpu);
int kvm_mips_set_count_ctl(struct kvm_vcpu *vcpu, s64 count_ctl);
int kvm_mips_set_count_resume(struct kvm_vcpu *vcpu, s64 count_resume);
int kvm_mips_set_count_hz(struct kvm_vcpu *vcpu, s64 count_hz);
void kvm_mips_count_enable_cause(struct kvm_vcpu *vcpu);
void kvm_mips_count_disable_cause(struct kvm_vcpu *vcpu);
enum hrtimer_restart kvm_mips_count_timeout(struct kvm_vcpu *vcpu);