ubuntu-linux-kernel/virt/kvm/arm/hyp/timer-sr.c

61 lines
1.7 KiB
C

/*
* Copyright (C) 2012-2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@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 <clocksource/arm_arch_timer.h>
#include <linux/compiler.h>
#include <linux/kvm_host.h>
#include <asm/kvm_hyp.h>
void __hyp_text __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high)
{
u64 cntvoff = (u64)cntvoff_high << 32 | cntvoff_low;
write_sysreg(cntvoff, cntvoff_el2);
}
void __hyp_text __timer_disable_traps(struct kvm_vcpu *vcpu)
{
/*
* We don't need to do this for VHE since the host kernel runs in EL2
* with HCR_EL2.TGE ==1, which makes those bits have no impact.
*/
if (!has_vhe()) {
u64 val;
/* Allow physical timer/counter access for the host */
val = read_sysreg(cnthctl_el2);
val |= CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN;
write_sysreg(val, cnthctl_el2);
}
}
void __hyp_text __timer_enable_traps(struct kvm_vcpu *vcpu)
{
if (!has_vhe()) {
u64 val;
/*
* Disallow physical timer access for the guest
* Physical counter access is allowed
*/
val = read_sysreg(cnthctl_el2);
val &= ~CNTHCTL_EL1PCEN;
val |= CNTHCTL_EL1PCTEN;
write_sysreg(val, cnthctl_el2);
}
}