1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012-2015 - ARM Ltd
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  */
6 
7 #include <clocksource/arm_arch_timer.h>
8 #include <linux/compiler.h>
9 #include <linux/kvm_host.h>
10 
11 #include <asm/kvm_hyp.h>
12 
__kvm_timer_set_cntvoff(u64 cntvoff)13 void __kvm_timer_set_cntvoff(u64 cntvoff)
14 {
15 	write_sysreg(cntvoff, cntvoff_el2);
16 }
17 
18 /*
19  * Should only be called on non-VHE systems.
20  * VHE systems use EL2 timers and configure EL1 timers in kvm_timer_init_vhe().
21  */
__timer_disable_traps(struct kvm_vcpu * vcpu)22 void __timer_disable_traps(struct kvm_vcpu *vcpu)
23 {
24 	u64 val;
25 
26 	/* Allow physical timer/counter access for the host */
27 	val = read_sysreg(cnthctl_el2);
28 	val |= CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN;
29 	write_sysreg(val, cnthctl_el2);
30 }
31 
32 /*
33  * Should only be called on non-VHE systems.
34  * VHE systems use EL2 timers and configure EL1 timers in kvm_timer_init_vhe().
35  */
__timer_enable_traps(struct kvm_vcpu * vcpu)36 void __timer_enable_traps(struct kvm_vcpu *vcpu)
37 {
38 	u64 val;
39 
40 	/*
41 	 * Disallow physical timer access for the guest
42 	 * Physical counter access is allowed
43 	 */
44 	val = read_sysreg(cnthctl_el2);
45 	val &= ~CNTHCTL_EL1PCEN;
46 	val |= CNTHCTL_EL1PCTEN;
47 	write_sysreg(val, cnthctl_el2);
48 }
49