/*- * Copyright (c) 2015,2016 Microsoft Corp. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #define VMBUS_ET_NAME "hvet" #define MSR_HV_STIMER0_CFG_SINT \ ((((uint64_t)VMBUS_SINT_TIMER) << MSR_HV_STIMER_CFG_SINT_SHIFT) & \ MSR_HV_STIMER_CFG_SINT_MASK) /* * Two additionally required features: * - SynIC is needed for interrupt generation. * - Time reference counter is needed to set ABS reference count to * STIMER0_COUNT. */ #define CPUID_HV_ET_MASK (CPUID_HV_MSR_TIME_REFCNT | \ CPUID_HV_MSR_SYNIC | \ CPUID_HV_MSR_SYNTIMER) static void vmbus_et_identify(driver_t *, device_t); static int vmbus_et_probe(device_t); static int vmbus_et_attach(device_t); static int vmbus_et_detach(device_t); static int vmbus_et_start(struct eventtimer *, sbintime_t, sbintime_t); static struct eventtimer vmbus_et; static device_method_t vmbus_et_methods[] = { DEVMETHOD(device_identify, vmbus_et_identify), DEVMETHOD(device_probe, vmbus_et_probe), DEVMETHOD(device_attach, vmbus_et_attach), DEVMETHOD(device_detach, vmbus_et_detach), DEVMETHOD_END }; static driver_t vmbus_et_driver = { VMBUS_ET_NAME, vmbus_et_methods, 0 }; static devclass_t vmbus_et_devclass; DRIVER_MODULE(hv_et, vmbus, vmbus_et_driver, vmbus_et_devclass, NULL, NULL); MODULE_VERSION(hv_et, 1); static __inline uint64_t hyperv_sbintime2count(sbintime_t time) { struct timespec val; val = sbttots(time); return (val.tv_sec * HYPERV_TIMER_FREQ) + (val.tv_nsec / HYPERV_TIMER_NS_FACTOR); } static int vmbus_et_start(struct eventtimer *et __unused, sbintime_t first, sbintime_t period __unused) { uint64_t current; current = rdmsr(MSR_HV_TIME_REF_COUNT); current += hyperv_sbintime2count(first); wrmsr(MSR_HV_STIMER0_COUNT, current); return (0); } void vmbus_et_intr(struct trapframe *frame) { struct trapframe *oldframe; struct thread *td; if (vmbus_et.et_active) { td = curthread; td->td_intr_nesting_level++; oldframe = td->td_intr_frame; td->td_intr_frame = frame; vmbus_et.et_event_cb(&vmbus_et, vmbus_et.et_arg); td->td_intr_frame = oldframe; td->td_intr_nesting_level--; } } static void vmbus_et_identify(driver_t *driver, device_t parent) { if (device_get_unit(parent) != 0 || device_find_child(parent, VMBUS_ET_NAME, -1) != NULL || (hyperv_features & CPUID_HV_ET_MASK) != CPUID_HV_ET_MASK) return; device_add_child(parent, VMBUS_ET_NAME, -1); } static int vmbus_et_probe(device_t dev) { if (resource_disabled(VMBUS_ET_NAME, 0)) return (ENXIO); device_set_desc(dev, "Hyper-V event timer"); return (BUS_PROBE_NOWILDCARD); } static void vmbus_et_config(void *arg __unused) { /* * Make sure that STIMER0 is really disabled before writing * to STIMER0_CONFIG. * * "Writing to the configuration register of a timer that * is already enabled may result in undefined behaviour." */ for (;;) { uint64_t val; /* Stop counting, and this also implies disabling STIMER0 */ wrmsr(MSR_HV_STIMER0_COUNT, 0); val = rdmsr(MSR_HV_STIMER0_CONFIG); if ((val & MSR_HV_STIMER_CFG_ENABLE) == 0) break; cpu_spinwait(); } wrmsr(MSR_HV_STIMER0_CONFIG, MSR_HV_STIMER_CFG_AUTOEN | MSR_HV_STIMER0_CFG_SINT); } static int vmbus_et_attach(device_t dev) { /* TODO: use independent IDT vector */ vmbus_et.et_name = "Hyper-V"; vmbus_et.et_flags = ET_FLAGS_ONESHOT | ET_FLAGS_PERCPU; vmbus_et.et_quality = 1000; vmbus_et.et_frequency = HYPERV_TIMER_FREQ; vmbus_et.et_min_period = (0x00000001ULL << 32) / HYPERV_TIMER_FREQ; vmbus_et.et_max_period = (0xfffffffeULL << 32) / HYPERV_TIMER_FREQ; vmbus_et.et_start = vmbus_et_start; /* * Delay a bit to make sure that MSR_HV_TIME_REF_COUNT will * not return 0, since writing 0 to STIMER0_COUNT will disable * STIMER0. */ DELAY(100); smp_rendezvous(NULL, vmbus_et_config, NULL, NULL); return (et_register(&vmbus_et)); } static int vmbus_et_detach(device_t dev) { return (et_deregister(&vmbus_et)); }