vmbus_et.c revision 300988
1293873Ssephe/*- 2298446Ssephe * Copyright (c) 2015,2016 Microsoft Corp. 3293873Ssephe * All rights reserved. 4293873Ssephe * 5293873Ssephe * Redistribution and use in source and binary forms, with or without 6293873Ssephe * modification, are permitted provided that the following conditions 7293873Ssephe * are met: 8293873Ssephe * 1. Redistributions of source code must retain the above copyright 9293873Ssephe * notice, this list of conditions and the following disclaimer. 10293873Ssephe * 2. Redistributions in binary form must reproduce the above copyright 11293873Ssephe * notice, this list of conditions and the following disclaimer in the 12293873Ssephe * documentation and/or other materials provided with the distribution. 13293873Ssephe * 14293873Ssephe * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15293873Ssephe * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16293873Ssephe * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17293873Ssephe * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18293873Ssephe * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19293873Ssephe * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20293873Ssephe * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21293873Ssephe * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22293873Ssephe * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23293873Ssephe * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24293873Ssephe * SUCH DAMAGE. 25293873Ssephe */ 26293873Ssephe 27293873Ssephe#include <sys/cdefs.h> 28293873Ssephe__FBSDID("$FreeBSD: head/sys/dev/hyperv/vmbus/hv_et.c 300988 2016-05-30 08:42:35Z sephe $"); 29293873Ssephe 30293873Ssephe#include <sys/param.h> 31298449Ssephe#include <sys/bus.h> 32298449Ssephe#include <sys/kernel.h> 33298449Ssephe#include <sys/module.h> 34293873Ssephe#include <sys/proc.h> 35293873Ssephe#include <sys/systm.h> 36293873Ssephe#include <sys/smp.h> 37293873Ssephe#include <sys/time.h> 38293873Ssephe#include <sys/timeet.h> 39293873Ssephe 40300827Ssephe#include <dev/hyperv/vmbus/hyperv_reg.h> 41300834Ssephe#include <dev/hyperv/vmbus/hyperv_var.h> 42300988Ssephe#include <dev/hyperv/vmbus/vmbus_var.h> 43293873Ssephe 44293873Ssephe#define HV_TIMER_FREQUENCY (10 * 1000 * 1000LL) /* 100ns period */ 45293873Ssephe#define HV_MAX_DELTA_TICKS 0xffffffffLL 46293873Ssephe#define HV_MIN_DELTA_TICKS 1LL 47293873Ssephe 48300827Ssephe#define MSR_HV_STIMER0_CFG_SINT \ 49300988Ssephe ((((uint64_t)VMBUS_SINT_TIMER) << MSR_HV_STIMER_CFG_SINT_SHIFT) & \ 50300827Ssephe MSR_HV_STIMER_CFG_SINT_MASK) 51300827Ssephe 52300834Ssephe/* 53300834Ssephe * Two additionally required features: 54300834Ssephe * - SynIC is needed for interrupt generation. 55300834Ssephe * - Time reference counter is needed to set ABS reference count to 56300834Ssephe * STIMER0_COUNT. 57300834Ssephe */ 58300834Ssephe#define CPUID_HV_ET_MASK (CPUID_HV_MSR_TIME_REFCNT | \ 59300834Ssephe CPUID_HV_MSR_SYNIC | \ 60300834Ssephe CPUID_HV_MSR_SYNTIMER) 61300834Ssephe 62298449Ssephestatic struct eventtimer *et; 63293873Ssephe 64300987Ssephestatic __inline uint64_t 65293873Ssephesbintime2tick(sbintime_t time) 66293873Ssephe{ 67293873Ssephe struct timespec val; 68293873Ssephe 69293873Ssephe val = sbttots(time); 70300987Ssephe return (val.tv_sec * HV_TIMER_FREQUENCY) + (val.tv_nsec / 100); 71293873Ssephe} 72293873Ssephe 73293873Ssephestatic int 74293873Ssephehv_et_start(struct eventtimer *et, sbintime_t firsttime, sbintime_t periodtime) 75293873Ssephe{ 76300987Ssephe uint64_t current; 77293873Ssephe 78300827Ssephe current = rdmsr(MSR_HV_TIME_REF_COUNT); 79293873Ssephe current += sbintime2tick(firsttime); 80300827Ssephe wrmsr(MSR_HV_STIMER0_COUNT, current); 81293873Ssephe 82293873Ssephe return (0); 83293873Ssephe} 84293873Ssephe 85293873Ssephevoid 86300988Ssephevmbus_et_intr(struct trapframe *frame) 87293873Ssephe{ 88293873Ssephe struct trapframe *oldframe; 89293873Ssephe struct thread *td; 90293873Ssephe 91298449Ssephe if (et->et_active) { 92293873Ssephe td = curthread; 93293873Ssephe td->td_intr_nesting_level++; 94293873Ssephe oldframe = td->td_intr_frame; 95293873Ssephe td->td_intr_frame = frame; 96298449Ssephe et->et_event_cb(et, et->et_arg); 97293873Ssephe td->td_intr_frame = oldframe; 98293873Ssephe td->td_intr_nesting_level--; 99293873Ssephe } 100293873Ssephe} 101293873Ssephe 102298449Ssephestatic void 103298568Ssephehv_et_identify(driver_t *driver, device_t parent) 104293873Ssephe{ 105300834Ssephe if (device_find_child(parent, "hv_et", -1) != NULL || 106300834Ssephe (hyperv_features & CPUID_HV_ET_MASK) != CPUID_HV_ET_MASK) 107298449Ssephe return; 108298449Ssephe 109298449Ssephe device_add_child(parent, "hv_et", -1); 110293873Ssephe} 111293873Ssephe 112298449Ssephestatic int 113298449Ssephehv_et_probe(device_t dev) 114298449Ssephe{ 115298449Ssephe device_set_desc(dev, "Hyper-V event timer"); 116298449Ssephe 117298449Ssephe return (BUS_PROBE_NOWILDCARD); 118298449Ssephe} 119298449Ssephe 120300987Ssephestatic void 121300987Ssephevmbus_et_config(void *arg __unused) 122300987Ssephe{ 123300987Ssephe /* 124300987Ssephe * Make sure that STIMER0 is really disabled before writing 125300987Ssephe * to STIMER0_CONFIG. 126300987Ssephe * 127300987Ssephe * "Writing to the configuration register of a timer that 128300987Ssephe * is already enabled may result in undefined behaviour." 129300987Ssephe */ 130300987Ssephe for (;;) { 131300987Ssephe uint64_t val; 132300987Ssephe 133300987Ssephe /* Stop counting, and this also implies disabling STIMER0 */ 134300987Ssephe wrmsr(MSR_HV_STIMER0_COUNT, 0); 135300987Ssephe 136300987Ssephe val = rdmsr(MSR_HV_STIMER0_CONFIG); 137300987Ssephe if ((val & MSR_HV_STIMER_CFG_ENABLE) == 0) 138300987Ssephe break; 139300987Ssephe cpu_spinwait(); 140300987Ssephe } 141300987Ssephe wrmsr(MSR_HV_STIMER0_CONFIG, 142300987Ssephe MSR_HV_STIMER_CFG_AUTOEN | MSR_HV_STIMER0_CFG_SINT); 143300987Ssephe} 144300987Ssephe 145298449Ssephestatic int 146298449Ssephehv_et_attach(device_t dev) 147298449Ssephe{ 148298449Ssephe /* XXX: need allocate SINT and remove global et */ 149298449Ssephe et = device_get_softc(dev); 150298449Ssephe 151298449Ssephe et->et_name = "Hyper-V"; 152298449Ssephe et->et_flags = ET_FLAGS_ONESHOT | ET_FLAGS_PERCPU; 153298449Ssephe et->et_quality = 1000; 154298449Ssephe et->et_frequency = HV_TIMER_FREQUENCY; 155298449Ssephe et->et_min_period = HV_MIN_DELTA_TICKS * ((1LL << 32) / HV_TIMER_FREQUENCY); 156298449Ssephe et->et_max_period = HV_MAX_DELTA_TICKS * ((1LL << 32) / HV_TIMER_FREQUENCY); 157298449Ssephe et->et_start = hv_et_start; 158298449Ssephe et->et_priv = dev; 159298449Ssephe 160300987Ssephe /* 161300987Ssephe * Delay a bit to make sure that MSR_HV_TIME_REF_COUNT will 162300987Ssephe * not return 0, since writing 0 to STIMER0_COUNT will disable 163300987Ssephe * STIMER0. 164300987Ssephe */ 165300987Ssephe DELAY(100); 166300987Ssephe smp_rendezvous(NULL, vmbus_et_config, NULL, NULL); 167300987Ssephe 168298449Ssephe return (et_register(et)); 169298449Ssephe} 170298449Ssephe 171298449Ssephestatic int 172298449Ssephehv_et_detach(device_t dev) 173298449Ssephe{ 174298449Ssephe return (et_deregister(et)); 175298449Ssephe} 176298449Ssephe 177298449Ssephestatic device_method_t hv_et_methods[] = { 178298449Ssephe DEVMETHOD(device_identify, hv_et_identify), 179298449Ssephe DEVMETHOD(device_probe, hv_et_probe), 180298449Ssephe DEVMETHOD(device_attach, hv_et_attach), 181298449Ssephe DEVMETHOD(device_detach, hv_et_detach), 182298449Ssephe 183298449Ssephe DEVMETHOD_END 184298449Ssephe}; 185298449Ssephe 186298449Ssephestatic driver_t hv_et_driver = { 187298449Ssephe "hv_et", 188298449Ssephe hv_et_methods, 189298449Ssephe sizeof(struct eventtimer) 190298449Ssephe}; 191298449Ssephe 192298449Ssephestatic devclass_t hv_et_devclass; 193298449SsepheDRIVER_MODULE(hv_et, vmbus, hv_et_driver, hv_et_devclass, NULL, 0); 194298449SsepheMODULE_VERSION(hv_et, 1); 195