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path: root/drivers/gpu/drm/nouveau/nvkm/subdev/timer/base.c
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Diffstat (limited to 'drivers/gpu/drm/nouveau/nvkm/subdev/timer/base.c')
-rw-r--r--drivers/gpu/drm/nouveau/nvkm/subdev/timer/base.c198
1 files changed, 198 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/timer/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/timer/base.c
new file mode 100644
index 000000000..8b0da0c06
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/timer/base.c
@@ -0,0 +1,198 @@
+/*
+ * Copyright 2012 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Ben Skeggs
+ */
+#include "priv.h"
+
+s64
+nvkm_timer_wait_test(struct nvkm_timer_wait *wait)
+{
+ struct nvkm_subdev *subdev = &wait->tmr->subdev;
+ u64 time = nvkm_timer_read(wait->tmr);
+
+ if (wait->reads == 0) {
+ wait->time0 = time;
+ wait->time1 = time;
+ }
+
+ if (wait->time1 == time) {
+ if (wait->reads++ == 16) {
+ nvkm_fatal(subdev, "stalled at %016llx\n", time);
+ return -ETIMEDOUT;
+ }
+ } else {
+ wait->time1 = time;
+ wait->reads = 1;
+ }
+
+ if (wait->time1 - wait->time0 > wait->limit)
+ return -ETIMEDOUT;
+
+ return wait->time1 - wait->time0;
+}
+
+void
+nvkm_timer_wait_init(struct nvkm_device *device, u64 nsec,
+ struct nvkm_timer_wait *wait)
+{
+ wait->tmr = device->timer;
+ wait->limit = nsec;
+ wait->reads = 0;
+}
+
+u64
+nvkm_timer_read(struct nvkm_timer *tmr)
+{
+ return tmr->func->read(tmr);
+}
+
+void
+nvkm_timer_alarm_trigger(struct nvkm_timer *tmr)
+{
+ struct nvkm_alarm *alarm, *atemp;
+ unsigned long flags;
+ LIST_HEAD(exec);
+
+ /* Process pending alarms. */
+ spin_lock_irqsave(&tmr->lock, flags);
+ list_for_each_entry_safe(alarm, atemp, &tmr->alarms, head) {
+ /* Have we hit the earliest alarm that hasn't gone off? */
+ if (alarm->timestamp > nvkm_timer_read(tmr)) {
+ /* Schedule it. If we didn't race, we're done. */
+ tmr->func->alarm_init(tmr, alarm->timestamp);
+ if (alarm->timestamp > nvkm_timer_read(tmr))
+ break;
+ }
+
+ /* Move to completed list. We'll drop the lock before
+ * executing the callback so it can reschedule itself.
+ */
+ list_del_init(&alarm->head);
+ list_add(&alarm->exec, &exec);
+ }
+
+ /* Shut down interrupt if no more pending alarms. */
+ if (list_empty(&tmr->alarms))
+ tmr->func->alarm_fini(tmr);
+ spin_unlock_irqrestore(&tmr->lock, flags);
+
+ /* Execute completed callbacks. */
+ list_for_each_entry_safe(alarm, atemp, &exec, exec) {
+ list_del(&alarm->exec);
+ alarm->func(alarm);
+ }
+}
+
+void
+nvkm_timer_alarm(struct nvkm_timer *tmr, u32 nsec, struct nvkm_alarm *alarm)
+{
+ struct nvkm_alarm *list;
+ unsigned long flags;
+
+ /* Remove alarm from pending list.
+ *
+ * This both protects against the corruption of the list,
+ * and implements alarm rescheduling/cancellation.
+ */
+ spin_lock_irqsave(&tmr->lock, flags);
+ list_del_init(&alarm->head);
+
+ if (nsec) {
+ /* Insert into pending list, ordered earliest to latest. */
+ alarm->timestamp = nvkm_timer_read(tmr) + nsec;
+ list_for_each_entry(list, &tmr->alarms, head) {
+ if (list->timestamp > alarm->timestamp)
+ break;
+ }
+
+ list_add_tail(&alarm->head, &list->head);
+
+ /* Update HW if this is now the earliest alarm. */
+ list = list_first_entry(&tmr->alarms, typeof(*list), head);
+ if (list == alarm) {
+ tmr->func->alarm_init(tmr, alarm->timestamp);
+ /* This shouldn't happen if callers aren't stupid.
+ *
+ * Worst case scenario is that it'll take roughly
+ * 4 seconds for the next alarm to trigger.
+ */
+ WARN_ON(alarm->timestamp <= nvkm_timer_read(tmr));
+ }
+ }
+ spin_unlock_irqrestore(&tmr->lock, flags);
+}
+
+static void
+nvkm_timer_intr(struct nvkm_subdev *subdev)
+{
+ struct nvkm_timer *tmr = nvkm_timer(subdev);
+ tmr->func->intr(tmr);
+}
+
+static int
+nvkm_timer_fini(struct nvkm_subdev *subdev, bool suspend)
+{
+ struct nvkm_timer *tmr = nvkm_timer(subdev);
+ tmr->func->alarm_fini(tmr);
+ return 0;
+}
+
+static int
+nvkm_timer_init(struct nvkm_subdev *subdev)
+{
+ struct nvkm_timer *tmr = nvkm_timer(subdev);
+ if (tmr->func->init)
+ tmr->func->init(tmr);
+ tmr->func->time(tmr, ktime_to_ns(ktime_get()));
+ nvkm_timer_alarm_trigger(tmr);
+ return 0;
+}
+
+static void *
+nvkm_timer_dtor(struct nvkm_subdev *subdev)
+{
+ return nvkm_timer(subdev);
+}
+
+static const struct nvkm_subdev_func
+nvkm_timer = {
+ .dtor = nvkm_timer_dtor,
+ .init = nvkm_timer_init,
+ .fini = nvkm_timer_fini,
+ .intr = nvkm_timer_intr,
+};
+
+int
+nvkm_timer_new_(const struct nvkm_timer_func *func, struct nvkm_device *device,
+ enum nvkm_subdev_type type, int inst, struct nvkm_timer **ptmr)
+{
+ struct nvkm_timer *tmr;
+
+ if (!(tmr = *ptmr = kzalloc(sizeof(*tmr), GFP_KERNEL)))
+ return -ENOMEM;
+
+ nvkm_subdev_ctor(&nvkm_timer, device, type, inst, &tmr->subdev);
+ tmr->func = func;
+ INIT_LIST_HEAD(&tmr->alarms);
+ spin_lock_init(&tmr->lock);
+ return 0;
+}