diff options
author | Raghavendra Rao Ananta <rananta@google.com> | 2021-10-07 23:34:30 +0000 |
---|---|---|
committer | Marc Zyngier <maz@kernel.org> | 2021-10-17 11:17:20 +0100 |
commit | d977ed39940231839f6856637fe24f41860f7969 (patch) | |
tree | cfcc163c7bd242c3768ead995d74843204b4b80f /tools/testing/selftests | |
parent | 740826ec02a65a5b25335fddfe8bce4ac99c7a11 (diff) | |
download | linux-d977ed39940231839f6856637fe24f41860f7969.tar.bz2 |
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: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211007233439.1826892-7-rananta@google.com
Diffstat (limited to 'tools/testing/selftests')
-rw-r--r-- | tools/testing/selftests/kvm/include/aarch64/arch_timer.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/include/aarch64/arch_timer.h b/tools/testing/selftests/kvm/include/aarch64/arch_timer.h new file mode 100644 index 000000000000..cb7c03de3a21 --- /dev/null +++ b/tools/testing/selftests/kvm/include/aarch64/arch_timer.h @@ -0,0 +1,142 @@ +/* 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 */ |