vmbus_et.c revision 307466
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: stable/11/sys/dev/hyperv/vmbus/vmbus_et.c 307466 2016-10-17 03:48:22Z 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> 35307466Ssephe#include <sys/smp.h> 36293873Ssephe#include <sys/systm.h> 37293873Ssephe#include <sys/timeet.h> 38293873Ssephe 39300827Ssephe#include <dev/hyperv/vmbus/hyperv_reg.h> 40300834Ssephe#include <dev/hyperv/vmbus/hyperv_var.h> 41300988Ssephe#include <dev/hyperv/vmbus/vmbus_var.h> 42293873Ssephe 43300993Ssephe#define VMBUS_ET_NAME "hvet" 44300993Ssephe 45300827Ssephe#define MSR_HV_STIMER0_CFG_SINT \ 46300988Ssephe ((((uint64_t)VMBUS_SINT_TIMER) << MSR_HV_STIMER_CFG_SINT_SHIFT) & \ 47300827Ssephe MSR_HV_STIMER_CFG_SINT_MASK) 48300827Ssephe 49300834Ssephe/* 50300834Ssephe * Two additionally required features: 51300834Ssephe * - SynIC is needed for interrupt generation. 52300834Ssephe * - Time reference counter is needed to set ABS reference count to 53300834Ssephe * STIMER0_COUNT. 54300834Ssephe */ 55300834Ssephe#define CPUID_HV_ET_MASK (CPUID_HV_MSR_TIME_REFCNT | \ 56300834Ssephe CPUID_HV_MSR_SYNIC | \ 57300834Ssephe CPUID_HV_MSR_SYNTIMER) 58300834Ssephe 59307466Ssephestatic void vmbus_et_identify(driver_t *, device_t); 60307466Ssephestatic int vmbus_et_probe(device_t); 61307466Ssephestatic int vmbus_et_attach(device_t); 62307466Ssephestatic int vmbus_et_detach(device_t); 63307466Ssephestatic int vmbus_et_start(struct eventtimer *, sbintime_t, 64307466Ssephe sbintime_t); 65307466Ssephe 66300989Ssephestatic struct eventtimer vmbus_et; 67293873Ssephe 68307466Ssephestatic device_method_t vmbus_et_methods[] = { 69307466Ssephe DEVMETHOD(device_identify, vmbus_et_identify), 70307466Ssephe DEVMETHOD(device_probe, vmbus_et_probe), 71307466Ssephe DEVMETHOD(device_attach, vmbus_et_attach), 72307466Ssephe DEVMETHOD(device_detach, vmbus_et_detach), 73307466Ssephe 74307466Ssephe DEVMETHOD_END 75307466Ssephe}; 76307466Ssephe 77307466Ssephestatic driver_t vmbus_et_driver = { 78307466Ssephe VMBUS_ET_NAME, 79307466Ssephe vmbus_et_methods, 80307466Ssephe 0 81307466Ssephe}; 82307466Ssephe 83307466Ssephestatic devclass_t vmbus_et_devclass; 84307466Ssephe 85307466SsepheDRIVER_MODULE(hv_et, vmbus, vmbus_et_driver, vmbus_et_devclass, NULL, NULL); 86307466SsepheMODULE_VERSION(hv_et, 1); 87307466Ssephe 88300987Ssephestatic __inline uint64_t 89300993Ssephehyperv_sbintime2count(sbintime_t time) 90293873Ssephe{ 91293873Ssephe struct timespec val; 92293873Ssephe 93293873Ssephe val = sbttots(time); 94300992Ssephe return (val.tv_sec * HYPERV_TIMER_FREQ) + 95300992Ssephe (val.tv_nsec / HYPERV_TIMER_NS_FACTOR); 96293873Ssephe} 97293873Ssephe 98293873Ssephestatic int 99300993Ssephevmbus_et_start(struct eventtimer *et __unused, sbintime_t first, 100300993Ssephe sbintime_t period __unused) 101293873Ssephe{ 102300987Ssephe uint64_t current; 103293873Ssephe 104300827Ssephe current = rdmsr(MSR_HV_TIME_REF_COUNT); 105300993Ssephe current += hyperv_sbintime2count(first); 106300827Ssephe wrmsr(MSR_HV_STIMER0_COUNT, current); 107293873Ssephe 108293873Ssephe return (0); 109293873Ssephe} 110293873Ssephe 111293873Ssephevoid 112300988Ssephevmbus_et_intr(struct trapframe *frame) 113293873Ssephe{ 114293873Ssephe struct trapframe *oldframe; 115293873Ssephe struct thread *td; 116293873Ssephe 117300989Ssephe if (vmbus_et.et_active) { 118293873Ssephe td = curthread; 119293873Ssephe td->td_intr_nesting_level++; 120293873Ssephe oldframe = td->td_intr_frame; 121293873Ssephe td->td_intr_frame = frame; 122300989Ssephe vmbus_et.et_event_cb(&vmbus_et, vmbus_et.et_arg); 123293873Ssephe td->td_intr_frame = oldframe; 124293873Ssephe td->td_intr_nesting_level--; 125293873Ssephe } 126293873Ssephe} 127293873Ssephe 128298449Ssephestatic void 129300993Ssephevmbus_et_identify(driver_t *driver, device_t parent) 130293873Ssephe{ 131300989Ssephe if (device_get_unit(parent) != 0 || 132300993Ssephe device_find_child(parent, VMBUS_ET_NAME, -1) != NULL || 133300834Ssephe (hyperv_features & CPUID_HV_ET_MASK) != CPUID_HV_ET_MASK) 134298449Ssephe return; 135298449Ssephe 136300993Ssephe device_add_child(parent, VMBUS_ET_NAME, -1); 137293873Ssephe} 138293873Ssephe 139298449Ssephestatic int 140300993Ssephevmbus_et_probe(device_t dev) 141298449Ssephe{ 142300994Ssephe if (resource_disabled(VMBUS_ET_NAME, 0)) 143300994Ssephe return (ENXIO); 144300994Ssephe 145298449Ssephe device_set_desc(dev, "Hyper-V event timer"); 146298449Ssephe 147298449Ssephe return (BUS_PROBE_NOWILDCARD); 148298449Ssephe} 149298449Ssephe 150300987Ssephestatic void 151300987Ssephevmbus_et_config(void *arg __unused) 152300987Ssephe{ 153300987Ssephe /* 154300987Ssephe * Make sure that STIMER0 is really disabled before writing 155300987Ssephe * to STIMER0_CONFIG. 156300987Ssephe * 157300987Ssephe * "Writing to the configuration register of a timer that 158300987Ssephe * is already enabled may result in undefined behaviour." 159300987Ssephe */ 160300987Ssephe for (;;) { 161300987Ssephe uint64_t val; 162300987Ssephe 163300987Ssephe /* Stop counting, and this also implies disabling STIMER0 */ 164300987Ssephe wrmsr(MSR_HV_STIMER0_COUNT, 0); 165300987Ssephe 166300987Ssephe val = rdmsr(MSR_HV_STIMER0_CONFIG); 167300987Ssephe if ((val & MSR_HV_STIMER_CFG_ENABLE) == 0) 168300987Ssephe break; 169300987Ssephe cpu_spinwait(); 170300987Ssephe } 171300987Ssephe wrmsr(MSR_HV_STIMER0_CONFIG, 172300987Ssephe MSR_HV_STIMER_CFG_AUTOEN | MSR_HV_STIMER0_CFG_SINT); 173300987Ssephe} 174300987Ssephe 175298449Ssephestatic int 176300993Ssephevmbus_et_attach(device_t dev) 177298449Ssephe{ 178300989Ssephe /* TODO: use independent IDT vector */ 179298449Ssephe 180300989Ssephe vmbus_et.et_name = "Hyper-V"; 181300989Ssephe vmbus_et.et_flags = ET_FLAGS_ONESHOT | ET_FLAGS_PERCPU; 182300989Ssephe vmbus_et.et_quality = 1000; 183300992Ssephe vmbus_et.et_frequency = HYPERV_TIMER_FREQ; 184300992Ssephe vmbus_et.et_min_period = (0x00000001ULL << 32) / HYPERV_TIMER_FREQ; 185300992Ssephe vmbus_et.et_max_period = (0xfffffffeULL << 32) / HYPERV_TIMER_FREQ; 186300993Ssephe vmbus_et.et_start = vmbus_et_start; 187298449Ssephe 188300987Ssephe /* 189300987Ssephe * Delay a bit to make sure that MSR_HV_TIME_REF_COUNT will 190300987Ssephe * not return 0, since writing 0 to STIMER0_COUNT will disable 191300987Ssephe * STIMER0. 192300987Ssephe */ 193300987Ssephe DELAY(100); 194300987Ssephe smp_rendezvous(NULL, vmbus_et_config, NULL, NULL); 195300987Ssephe 196300989Ssephe return (et_register(&vmbus_et)); 197298449Ssephe} 198298449Ssephe 199298449Ssephestatic int 200300993Ssephevmbus_et_detach(device_t dev) 201298449Ssephe{ 202300989Ssephe return (et_deregister(&vmbus_et)); 203298449Ssephe} 204