Implement the timer save restore as a direct translation of the assembly code version.
Signed-off-by: Marc Zyngier <marc.zyng...@arm.com> --- arch/arm64/kvm/hyp/Makefile | 1 + arch/arm64/kvm/hyp/hyp.h | 3 ++ arch/arm64/kvm/hyp/timer-sr.c | 68 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 72 insertions(+) create mode 100644 arch/arm64/kvm/hyp/timer-sr.c diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile index d1e38ce..455dc0a 100644 --- a/arch/arm64/kvm/hyp/Makefile +++ b/arch/arm64/kvm/hyp/Makefile @@ -4,3 +4,4 @@ obj-$(CONFIG_KVM_ARM_HOST) += vgic-v2-sr.o obj-$(CONFIG_KVM_ARM_HOST) += vgic-v3-sr.o +obj-$(CONFIG_KVM_ARM_HOST) += timer-sr.o diff --git a/arch/arm64/kvm/hyp/hyp.h b/arch/arm64/kvm/hyp/hyp.h index a31cb6e..86aa5a2 100644 --- a/arch/arm64/kvm/hyp/hyp.h +++ b/arch/arm64/kvm/hyp/hyp.h @@ -33,5 +33,8 @@ void __vgic_v2_restore_state(struct kvm_vcpu *vcpu); void __vgic_v3_save_state(struct kvm_vcpu *vcpu); void __vgic_v3_restore_state(struct kvm_vcpu *vcpu); +void __timer_save_state(struct kvm_vcpu *vcpu); +void __timer_restore_state(struct kvm_vcpu *vcpu); + #endif /* __ARM64_KVM_HYP_H__ */ diff --git a/arch/arm64/kvm/hyp/timer-sr.c b/arch/arm64/kvm/hyp/timer-sr.c new file mode 100644 index 0000000..1a1d2ac --- /dev/null +++ b/arch/arm64/kvm/hyp/timer-sr.c @@ -0,0 +1,68 @@ +/* + * Copyright (C) 2012-2015 - ARM Ltd + * Author: Marc Zyngier <marc.zyng...@arm.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/compiler.h> +#include <linux/kvm_host.h> + +#include <asm/kvm_mmu.h> + +#include "hyp.h" + +/* vcpu is already in the HYP VA space */ +void __hyp_text __timer_save_state(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = kern_hyp_va(vcpu->kvm); + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; + + if (kvm->arch.timer.enabled) { + timer->cntv_ctl = read_sysreg(cntv_ctl_el0); + isb(); + timer->cntv_cval = read_sysreg(cntv_cval_el0); + } + + /* Disable the virtual timer */ + write_sysreg(0, cntv_ctl_el0); + + /* Allow physical timer/counter access for the host */ + write_sysreg(read_sysreg(cnthctl_el2) | 3, cnthctl_el2); + + /* Clear cntvoff for the host */ + write_sysreg(0, cntvoff_el2); +} + +void __hyp_text __timer_restore_state(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = kern_hyp_va(vcpu->kvm); + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; + u64 val; + + /* + * Disallow physical timer access for the guest + * Physical counter access is allowed + */ + val = read_sysreg(cnthctl_el2); + val &= ~(1 << 1); + val |= 1; + write_sysreg(val, cnthctl_el2); + + if (kvm->arch.timer.enabled) { + write_sysreg(kvm->arch.timer.cntvoff, cntvoff_el2); + write_sysreg(timer->cntv_cval, cntv_cval_el0); + isb(); + write_sysreg(timer->cntv_ctl, cntv_ctl_el0); + } +} -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html