1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/fifo/chid.c b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/chid.c
new file mode 100644
index 000000000000..23944d95efd5
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/chid.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2020 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.
+ */
+#include "chid.h"
+
+void
+nvkm_chid_put(struct nvkm_chid *chid, int id, spinlock_t *data_lock)
+{
+	if (id >= 0) {
+		spin_lock_irq(&chid->lock);
+		spin_lock(data_lock);
+		chid->data[id] = NULL;
+		spin_unlock(data_lock);
+		clear_bit(id, chid->used);
+		spin_unlock_irq(&chid->lock);
+	}
+}
+
+int
+nvkm_chid_get(struct nvkm_chid *chid, void *data)
+{
+	int id = -1, cid;
+
+	spin_lock_irq(&chid->lock);
+	cid = find_first_zero_bit(chid->used, chid->nr);
+	if (cid < chid->nr) {
+		set_bit(cid, chid->used);
+		chid->data[cid] = data;
+		id = cid;
+	}
+	spin_unlock_irq(&chid->lock);
+	return id;
+}
+
+static void
+nvkm_chid_del(struct kref *kref)
+{
+	struct nvkm_chid *chid = container_of(kref, typeof(*chid), kref);
+
+	nvkm_event_fini(&chid->event);
+
+	kvfree(chid->data);
+	kfree(chid);
+}
+
+void
+nvkm_chid_unref(struct nvkm_chid **pchid)
+{
+	struct nvkm_chid *chid = *pchid;
+
+	if (!chid)
+		return;
+
+	kref_put(&chid->kref, nvkm_chid_del);
+	*pchid = NULL;
+}
+
+struct nvkm_chid *
+nvkm_chid_ref(struct nvkm_chid *chid)
+{
+	if (chid)
+		kref_get(&chid->kref);
+
+	return chid;
+}
+
+int
+nvkm_chid_new(const struct nvkm_event_func *func, struct nvkm_subdev *subdev,
+	      int nr, int first, int count, struct nvkm_chid **pchid)
+{
+	struct nvkm_chid *chid;
+	int id;
+
+	if (!(chid = *pchid = kzalloc(struct_size(chid, used, nr), GFP_KERNEL)))
+		return -ENOMEM;
+
+	kref_init(&chid->kref);
+	chid->nr = nr;
+	chid->mask = chid->nr - 1;
+	spin_lock_init(&chid->lock);
+
+	if (!(chid->data = kvzalloc(sizeof(*chid->data) * nr, GFP_KERNEL))) {
+		nvkm_chid_unref(pchid);
+		return -ENOMEM;
+	}
+
+	for (id = 0; id < first; id++)
+		__set_bit(id, chid->used);
+	for (id = first + count; id < nr; id++)
+		__set_bit(id, chid->used);
+
+	return nvkm_event_init(func, subdev, 1, nr, &chid->event);
+}