Commit d977ed39 authored by Raghavendra Rao Ananta's avatar Raghavendra Rao Ananta Committed by Marc Zyngier

KVM: arm64: selftests: Add basic support for arch_timers

Add a minimalistic library support to access the virtual timers,
that can be used for simple timing functionalities, such as
introducing delays in the guest.
Signed-off-by: default avatarRaghavendra Rao Ananta <rananta@google.com>
Reviewed-by: default avatarAndrew Jones <drjones@redhat.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211007233439.1826892-7-rananta@google.com
parent 740826ec
/* SPDX-License-Identifier: GPL-2.0 */
/*
* ARM Generic Timer specific interface
*/
#ifndef SELFTEST_KVM_ARCH_TIMER_H
#define SELFTEST_KVM_ARCH_TIMER_H
#include "processor.h"
enum arch_timer {
VIRTUAL,
PHYSICAL,
};
#define CTL_ENABLE (1 << 0)
#define CTL_IMASK (1 << 1)
#define CTL_ISTATUS (1 << 2)
#define msec_to_cycles(msec) \
(timer_get_cntfrq() * (uint64_t)(msec) / 1000)
#define usec_to_cycles(usec) \
(timer_get_cntfrq() * (uint64_t)(usec) / 1000000)
#define cycles_to_usec(cycles) \
((uint64_t)(cycles) * 1000000 / timer_get_cntfrq())
static inline uint32_t timer_get_cntfrq(void)
{
return read_sysreg(cntfrq_el0);
}
static inline uint64_t timer_get_cntct(enum arch_timer timer)
{
isb();
switch (timer) {
case VIRTUAL:
return read_sysreg(cntvct_el0);
case PHYSICAL:
return read_sysreg(cntpct_el0);
default:
GUEST_ASSERT_1(0, timer);
}
/* We should not reach here */
return 0;
}
static inline void timer_set_cval(enum arch_timer timer, uint64_t cval)
{
switch (timer) {
case VIRTUAL:
write_sysreg(cval, cntv_cval_el0);
break;
case PHYSICAL:
write_sysreg(cval, cntp_cval_el0);
break;
default:
GUEST_ASSERT_1(0, timer);
}
isb();
}
static inline uint64_t timer_get_cval(enum arch_timer timer)
{
switch (timer) {
case VIRTUAL:
return read_sysreg(cntv_cval_el0);
case PHYSICAL:
return read_sysreg(cntp_cval_el0);
default:
GUEST_ASSERT_1(0, timer);
}
/* We should not reach here */
return 0;
}
static inline void timer_set_tval(enum arch_timer timer, uint32_t tval)
{
switch (timer) {
case VIRTUAL:
write_sysreg(tval, cntv_tval_el0);
break;
case PHYSICAL:
write_sysreg(tval, cntp_tval_el0);
break;
default:
GUEST_ASSERT_1(0, timer);
}
isb();
}
static inline void timer_set_ctl(enum arch_timer timer, uint32_t ctl)
{
switch (timer) {
case VIRTUAL:
write_sysreg(ctl, cntv_ctl_el0);
break;
case PHYSICAL:
write_sysreg(ctl, cntp_ctl_el0);
break;
default:
GUEST_ASSERT_1(0, timer);
}
isb();
}
static inline uint32_t timer_get_ctl(enum arch_timer timer)
{
switch (timer) {
case VIRTUAL:
return read_sysreg(cntv_ctl_el0);
case PHYSICAL:
return read_sysreg(cntp_ctl_el0);
default:
GUEST_ASSERT_1(0, timer);
}
/* We should not reach here */
return 0;
}
static inline void timer_set_next_cval_ms(enum arch_timer timer, uint32_t msec)
{
uint64_t now_ct = timer_get_cntct(timer);
uint64_t next_ct = now_ct + msec_to_cycles(msec);
timer_set_cval(timer, next_ct);
}
static inline void timer_set_next_tval_ms(enum arch_timer timer, uint32_t msec)
{
timer_set_tval(timer, msec_to_cycles(msec));
}
#endif /* SELFTEST_KVM_ARCH_TIMER_H */
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