vmbus_et.c revision 300992
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 300992 2016-05-30 09:20:08Z 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 44300827Ssephe#define MSR_HV_STIMER0_CFG_SINT \ 45300988Ssephe ((((uint64_t)VMBUS_SINT_TIMER) << MSR_HV_STIMER_CFG_SINT_SHIFT) & \ 46300827Ssephe MSR_HV_STIMER_CFG_SINT_MASK) 47300827Ssephe 48300834Ssephe/* 49300834Ssephe * Two additionally required features: 50300834Ssephe * - SynIC is needed for interrupt generation. 51300834Ssephe * - Time reference counter is needed to set ABS reference count to 52300834Ssephe * STIMER0_COUNT. 53300834Ssephe */ 54300834Ssephe#define CPUID_HV_ET_MASK (CPUID_HV_MSR_TIME_REFCNT | \ 55300834Ssephe CPUID_HV_MSR_SYNIC | \ 56300834Ssephe CPUID_HV_MSR_SYNTIMER) 57300834Ssephe 58300989Ssephestatic struct eventtimer vmbus_et; 59293873Ssephe 60300987Ssephestatic __inline uint64_t 61293873Ssephesbintime2tick(sbintime_t time) 62293873Ssephe{ 63293873Ssephe struct timespec val; 64293873Ssephe 65293873Ssephe val = sbttots(time); 66300992Ssephe return (val.tv_sec * HYPERV_TIMER_FREQ) + 67300992Ssephe (val.tv_nsec / HYPERV_TIMER_NS_FACTOR); 68293873Ssephe} 69293873Ssephe 70293873Ssephestatic int 71293873Ssephehv_et_start(struct eventtimer *et, sbintime_t firsttime, sbintime_t periodtime) 72293873Ssephe{ 73300987Ssephe uint64_t current; 74293873Ssephe 75300827Ssephe current = rdmsr(MSR_HV_TIME_REF_COUNT); 76293873Ssephe current += sbintime2tick(firsttime); 77300827Ssephe wrmsr(MSR_HV_STIMER0_COUNT, current); 78293873Ssephe 79293873Ssephe return (0); 80293873Ssephe} 81293873Ssephe 82293873Ssephevoid 83300988Ssephevmbus_et_intr(struct trapframe *frame) 84293873Ssephe{ 85293873Ssephe struct trapframe *oldframe; 86293873Ssephe struct thread *td; 87293873Ssephe 88300989Ssephe if (vmbus_et.et_active) { 89293873Ssephe td = curthread; 90293873Ssephe td->td_intr_nesting_level++; 91293873Ssephe oldframe = td->td_intr_frame; 92293873Ssephe td->td_intr_frame = frame; 93300989Ssephe vmbus_et.et_event_cb(&vmbus_et, vmbus_et.et_arg); 94293873Ssephe td->td_intr_frame = oldframe; 95293873Ssephe td->td_intr_nesting_level--; 96293873Ssephe } 97293873Ssephe} 98293873Ssephe 99298449Ssephestatic void 100298568Ssephehv_et_identify(driver_t *driver, device_t parent) 101293873Ssephe{ 102300989Ssephe if (device_get_unit(parent) != 0 || 103300989Ssephe device_find_child(parent, "hv_et", -1) != NULL || 104300834Ssephe (hyperv_features & CPUID_HV_ET_MASK) != CPUID_HV_ET_MASK) 105298449Ssephe return; 106298449Ssephe 107298449Ssephe device_add_child(parent, "hv_et", -1); 108293873Ssephe} 109293873Ssephe 110298449Ssephestatic int 111298449Ssephehv_et_probe(device_t dev) 112298449Ssephe{ 113298449Ssephe device_set_desc(dev, "Hyper-V event timer"); 114298449Ssephe 115298449Ssephe return (BUS_PROBE_NOWILDCARD); 116298449Ssephe} 117298449Ssephe 118300987Ssephestatic void 119300987Ssephevmbus_et_config(void *arg __unused) 120300987Ssephe{ 121300987Ssephe /* 122300987Ssephe * Make sure that STIMER0 is really disabled before writing 123300987Ssephe * to STIMER0_CONFIG. 124300987Ssephe * 125300987Ssephe * "Writing to the configuration register of a timer that 126300987Ssephe * is already enabled may result in undefined behaviour." 127300987Ssephe */ 128300987Ssephe for (;;) { 129300987Ssephe uint64_t val; 130300987Ssephe 131300987Ssephe /* Stop counting, and this also implies disabling STIMER0 */ 132300987Ssephe wrmsr(MSR_HV_STIMER0_COUNT, 0); 133300987Ssephe 134300987Ssephe val = rdmsr(MSR_HV_STIMER0_CONFIG); 135300987Ssephe if ((val & MSR_HV_STIMER_CFG_ENABLE) == 0) 136300987Ssephe break; 137300987Ssephe cpu_spinwait(); 138300987Ssephe } 139300987Ssephe wrmsr(MSR_HV_STIMER0_CONFIG, 140300987Ssephe MSR_HV_STIMER_CFG_AUTOEN | MSR_HV_STIMER0_CFG_SINT); 141300987Ssephe} 142300987Ssephe 143298449Ssephestatic int 144298449Ssephehv_et_attach(device_t dev) 145298449Ssephe{ 146300989Ssephe /* TODO: use independent IDT vector */ 147298449Ssephe 148300989Ssephe vmbus_et.et_name = "Hyper-V"; 149300989Ssephe vmbus_et.et_flags = ET_FLAGS_ONESHOT | ET_FLAGS_PERCPU; 150300989Ssephe vmbus_et.et_quality = 1000; 151300992Ssephe vmbus_et.et_frequency = HYPERV_TIMER_FREQ; 152300992Ssephe vmbus_et.et_min_period = (0x00000001ULL << 32) / HYPERV_TIMER_FREQ; 153300992Ssephe vmbus_et.et_max_period = (0xfffffffeULL << 32) / HYPERV_TIMER_FREQ; 154300989Ssephe vmbus_et.et_start = hv_et_start; 155298449Ssephe 156300987Ssephe /* 157300987Ssephe * Delay a bit to make sure that MSR_HV_TIME_REF_COUNT will 158300987Ssephe * not return 0, since writing 0 to STIMER0_COUNT will disable 159300987Ssephe * STIMER0. 160300987Ssephe */ 161300987Ssephe DELAY(100); 162300987Ssephe smp_rendezvous(NULL, vmbus_et_config, NULL, NULL); 163300987Ssephe 164300989Ssephe return (et_register(&vmbus_et)); 165298449Ssephe} 166298449Ssephe 167298449Ssephestatic int 168298449Ssephehv_et_detach(device_t dev) 169298449Ssephe{ 170300989Ssephe return (et_deregister(&vmbus_et)); 171298449Ssephe} 172298449Ssephe 173298449Ssephestatic device_method_t hv_et_methods[] = { 174298449Ssephe DEVMETHOD(device_identify, hv_et_identify), 175298449Ssephe DEVMETHOD(device_probe, hv_et_probe), 176298449Ssephe DEVMETHOD(device_attach, hv_et_attach), 177298449Ssephe DEVMETHOD(device_detach, hv_et_detach), 178298449Ssephe 179298449Ssephe DEVMETHOD_END 180298449Ssephe}; 181298449Ssephe 182298449Ssephestatic driver_t hv_et_driver = { 183298449Ssephe "hv_et", 184298449Ssephe hv_et_methods, 185300989Ssephe 0 186298449Ssephe}; 187298449Ssephe 188298449Ssephestatic devclass_t hv_et_devclass; 189298449SsepheDRIVER_MODULE(hv_et, vmbus, hv_et_driver, hv_et_devclass, NULL, 0); 190298449SsepheMODULE_VERSION(hv_et, 1); 191