diff options
Diffstat (limited to 'drivers/clocksource/arm_arch_timer.c')
| -rw-r--r-- | drivers/clocksource/arm_arch_timer.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 8f12e223703f..e0f167e5e792 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -25,6 +25,8 @@ #include <linux/sched/clock.h> #include <linux/sched_clock.h> #include <linux/acpi.h> +#include <linux/arm-smccc.h> +#include <linux/ptp_kvm.h> #include <asm/arch_timer.h> #include <asm/virt.h> @@ -1659,3 +1661,35 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table) } TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init); #endif + +int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *ts, + struct clocksource **cs) +{ + struct arm_smccc_res hvc_res; + u32 ptp_counter; + ktime_t ktime; + + if (!IS_ENABLED(CONFIG_HAVE_ARM_SMCCC_DISCOVERY)) + return -EOPNOTSUPP; + + if (arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) + ptp_counter = KVM_PTP_VIRT_COUNTER; + else + ptp_counter = KVM_PTP_PHYS_COUNTER; + + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, + ptp_counter, &hvc_res); + + if ((int)(hvc_res.a0) < 0) + return -EOPNOTSUPP; + + ktime = (u64)hvc_res.a0 << 32 | hvc_res.a1; + *ts = ktime_to_timespec64(ktime); + if (cycle) + *cycle = (u64)hvc_res.a2 << 32 | hvc_res.a3; + if (cs) + *cs = &clocksource_counter; + + return 0; +} +EXPORT_SYMBOL_GPL(kvm_arch_ptp_get_crosststamp); |