1 /* 2 * Copyright 2012 Red Hat Inc. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 20 * OTHER DEALINGS IN THE SOFTWARE. 21 * 22 * Authors: Ben Skeggs 23 */ 24 #include "priv.h" 25 26 u64 27 nvkm_timer_read(struct nvkm_timer *tmr) 28 { 29 return tmr->func->read(tmr); 30 } 31 32 void 33 nvkm_timer_alarm_trigger(struct nvkm_timer *tmr) 34 { 35 struct nvkm_alarm *alarm, *atemp; 36 unsigned long flags; 37 LIST_HEAD(exec); 38 39 /* move any due alarms off the pending list */ 40 spin_lock_irqsave(&tmr->lock, flags); 41 list_for_each_entry_safe(alarm, atemp, &tmr->alarms, head) { 42 if (alarm->timestamp <= nvkm_timer_read(tmr)) 43 list_move_tail(&alarm->head, &exec); 44 } 45 46 /* reschedule interrupt for next alarm time */ 47 if (!list_empty(&tmr->alarms)) { 48 alarm = list_first_entry(&tmr->alarms, typeof(*alarm), head); 49 tmr->func->alarm_init(tmr, alarm->timestamp); 50 } else { 51 tmr->func->alarm_fini(tmr); 52 } 53 spin_unlock_irqrestore(&tmr->lock, flags); 54 55 /* execute any pending alarm handlers */ 56 list_for_each_entry_safe(alarm, atemp, &exec, head) { 57 list_del_init(&alarm->head); 58 alarm->func(alarm); 59 } 60 } 61 62 void 63 nvkm_timer_alarm(struct nvkm_timer *tmr, u32 nsec, struct nvkm_alarm *alarm) 64 { 65 struct nvkm_alarm *list; 66 unsigned long flags; 67 68 alarm->timestamp = nvkm_timer_read(tmr) + nsec; 69 70 /* append new alarm to list, in soonest-alarm-first order */ 71 spin_lock_irqsave(&tmr->lock, flags); 72 if (!nsec) { 73 if (!list_empty(&alarm->head)) 74 list_del(&alarm->head); 75 } else { 76 list_for_each_entry(list, &tmr->alarms, head) { 77 if (list->timestamp > alarm->timestamp) 78 break; 79 } 80 list_add_tail(&alarm->head, &list->head); 81 } 82 spin_unlock_irqrestore(&tmr->lock, flags); 83 84 /* process pending alarms */ 85 nvkm_timer_alarm_trigger(tmr); 86 } 87 88 void 89 nvkm_timer_alarm_cancel(struct nvkm_timer *tmr, struct nvkm_alarm *alarm) 90 { 91 unsigned long flags; 92 spin_lock_irqsave(&tmr->lock, flags); 93 list_del_init(&alarm->head); 94 spin_unlock_irqrestore(&tmr->lock, flags); 95 } 96 97 static void 98 nvkm_timer_intr(struct nvkm_subdev *subdev) 99 { 100 struct nvkm_timer *tmr = nvkm_timer(subdev); 101 tmr->func->intr(tmr); 102 } 103 104 static int 105 nvkm_timer_fini(struct nvkm_subdev *subdev, bool suspend) 106 { 107 struct nvkm_timer *tmr = nvkm_timer(subdev); 108 tmr->func->alarm_fini(tmr); 109 return 0; 110 } 111 112 static int 113 nvkm_timer_init(struct nvkm_subdev *subdev) 114 { 115 struct nvkm_timer *tmr = nvkm_timer(subdev); 116 if (tmr->func->init) 117 tmr->func->init(tmr); 118 tmr->func->time(tmr, ktime_to_ns(ktime_get())); 119 nvkm_timer_alarm_trigger(tmr); 120 return 0; 121 } 122 123 static void * 124 nvkm_timer_dtor(struct nvkm_subdev *subdev) 125 { 126 return nvkm_timer(subdev); 127 } 128 129 static const struct nvkm_subdev_func 130 nvkm_timer = { 131 .dtor = nvkm_timer_dtor, 132 .init = nvkm_timer_init, 133 .fini = nvkm_timer_fini, 134 .intr = nvkm_timer_intr, 135 }; 136 137 int 138 nvkm_timer_new_(const struct nvkm_timer_func *func, struct nvkm_device *device, 139 int index, struct nvkm_timer **ptmr) 140 { 141 struct nvkm_timer *tmr; 142 143 if (!(tmr = *ptmr = kzalloc(sizeof(*tmr), GFP_KERNEL))) 144 return -ENOMEM; 145 146 nvkm_subdev_ctor(&nvkm_timer, device, index, &tmr->subdev); 147 tmr->func = func; 148 INIT_LIST_HEAD(&tmr->alarms); 149 spin_lock_init(&tmr->lock); 150 return 0; 151 } 152