drm/nouveau/flcn: split msgqueue into multiple pieces

To make things clearer while modifying the interfaces, split msgqueue into
Queue Manager, Command Queue, and Message Queue.

There should be no code changes here, these will be done incrementally.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvkm/falcon/Kbuild

 # SPDX-License-Identifier: MIT
 nvkm-y += nvkm/falcon/base.o
+nvkm-y += nvkm/falcon/cmdq.o
+nvkm-y += nvkm/falcon/msgq.o
+nvkm-y += nvkm/falcon/qmgr.o
 nvkm-y += nvkm/falcon/v1.o
 nvkm-y += nvkm/falcon/msgqueue.o
 nvkm-y += nvkm/falcon/msgqueue_0137c63d.o

drivers/gpu/drm/nouveau/nvkm/falcon/cmdq.c

+/*
+ * Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved.
+ *
+ * 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 "qmgr.h"
+
+static bool
+cmd_queue_has_room(struct nvkm_msgqueue *priv,
+		   struct nvkm_msgqueue_queue *queue, u32 size, bool *rewind)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+	u32 head = nvkm_falcon_rd32(falcon, queue->head_reg);
+	u32 tail = nvkm_falcon_rd32(falcon, queue->tail_reg);
+	u32 free;
+
+	size = ALIGN(size, QUEUE_ALIGNMENT);
+
+	if (head >= tail) {
+		free = queue->offset + queue->size - head;
+		free -= HDR_SIZE;
+
+		if (size > free) {
+			*rewind = true;
+			head = queue->offset;
+		}
+	}
+
+	if (head < tail)
+		free = tail - head - 1;
+
+	return size <= free;
+}
+
+static int
+cmd_queue_push(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
+	       void *data, u32 size)
+{
+	nvkm_falcon_load_dmem(priv->falcon, data, queue->position, size, 0);
+	queue->position += ALIGN(size, QUEUE_ALIGNMENT);
+	return 0;
+}
+
+/* REWIND unit is always 0x00 */
+#define MSGQUEUE_UNIT_REWIND 0x00
+
+static void
+cmd_queue_rewind(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue)
+{
+	const struct nvkm_subdev *subdev = priv->falcon->owner;
+	struct nvkm_msgqueue_hdr cmd;
+	int err;
+
+	cmd.unit_id = MSGQUEUE_UNIT_REWIND;
+	cmd.size = sizeof(cmd);
+	err = cmd_queue_push(priv, queue, &cmd, cmd.size);
+	if (err)
+		nvkm_error(subdev, "queue %d rewind failed\n", queue->index);
+	else
+		nvkm_error(subdev, "queue %d rewinded\n", queue->index);
+
+	queue->position = queue->offset;
+}
+
+static int
+cmd_queue_open(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
+	       u32 size)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+	const struct nvkm_subdev *subdev = priv->falcon->owner;
+	bool rewind = false;
+
+	mutex_lock(&queue->mutex);
+
+	if (!cmd_queue_has_room(priv, queue, size, &rewind)) {
+		nvkm_error(subdev, "queue full\n");
+		mutex_unlock(&queue->mutex);
+		return -EAGAIN;
+	}
+
+	queue->position = nvkm_falcon_rd32(falcon, queue->head_reg);
+
+	if (rewind)
+		cmd_queue_rewind(priv, queue);
+
+	return 0;
+}
+
+static void
+cmd_queue_close(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
+		bool commit)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+
+	if (commit)
+		nvkm_falcon_wr32(falcon, queue->head_reg, queue->position);
+
+	mutex_unlock(&queue->mutex);
+}
+
+static int
+cmd_write(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_hdr *cmd,
+	  struct nvkm_msgqueue_queue *queue)
+{
+	const struct nvkm_subdev *subdev = priv->falcon->owner;
+	static unsigned timeout = 2000;
+	unsigned long end_jiffies = jiffies + msecs_to_jiffies(timeout);
+	int ret = -EAGAIN;
+	bool commit = true;
+
+	while (ret == -EAGAIN && time_before(jiffies, end_jiffies))
+		ret = cmd_queue_open(priv, queue, cmd->size);
+	if (ret) {
+		nvkm_error(subdev, "pmu_queue_open_write failed\n");
+		return ret;
+	}
+
+	ret = cmd_queue_push(priv, queue, cmd, cmd->size);
+	if (ret) {
+		nvkm_error(subdev, "pmu_queue_push failed\n");
+		commit = false;
+	}
+
+	cmd_queue_close(priv, queue, commit);
+	return ret;
+}
+
+/* specifies that we want to know the command status in the answer message */
+#define CMD_FLAGS_STATUS BIT(0)
+/* specifies that we want an interrupt when the answer message is queued */
+#define CMD_FLAGS_INTR BIT(1)
+
+int
+nvkm_msgqueue_post(struct nvkm_msgqueue *priv, enum msgqueue_msg_priority prio,
+		   struct nvkm_msgqueue_hdr *cmd, nvkm_msgqueue_callback cb,
+		   struct completion *completion, bool wait_init)
+{
+	struct nvkm_msgqueue_seq *seq;
+	struct nvkm_msgqueue_queue *queue;
+	int ret;
+
+	if (wait_init && !wait_for_completion_timeout(&priv->init_done,
+					 msecs_to_jiffies(1000)))
+		return -ETIMEDOUT;
+
+	queue = priv->func->cmd_queue(priv, prio);
+	if (IS_ERR(queue))
+		return PTR_ERR(queue);
+
+	seq = msgqueue_seq_acquire(priv);
+	if (IS_ERR(seq))
+		return PTR_ERR(seq);
+
+	cmd->seq_id = seq->id;
+	cmd->ctrl_flags = CMD_FLAGS_STATUS | CMD_FLAGS_INTR;
+
+	seq->callback = cb;
+	seq->state = SEQ_STATE_USED;
+	seq->completion = completion;
+
+	ret = cmd_write(priv, cmd, queue);
+	if (ret) {
+		seq->state = SEQ_STATE_PENDING;
+		msgqueue_seq_release(priv, seq);
+	}
+
+	return ret;
+}

drivers/gpu/drm/nouveau/nvkm/falcon/msgq.c

+/*
+ * Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved.
+ *
+ * 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 "qmgr.h"
+
+static int
+msg_queue_open(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+	mutex_lock(&queue->mutex);
+	queue->position = nvkm_falcon_rd32(falcon, queue->tail_reg);
+	return 0;
+}
+
+static void
+msg_queue_close(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
+		bool commit)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+
+	if (commit)
+		nvkm_falcon_wr32(falcon, queue->tail_reg, queue->position);
+
+	mutex_unlock(&queue->mutex);
+}
+
+static bool
+msg_queue_empty(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+	u32 head = nvkm_falcon_rd32(falcon, queue->head_reg);
+	u32 tail = nvkm_falcon_rd32(falcon, queue->tail_reg);
+	return head == tail;
+}
+
+static int
+msg_queue_pop(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
+	      void *data, u32 size)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+	const struct nvkm_subdev *subdev = priv->falcon->owner;
+	u32 head, tail, available;
+
+	head = nvkm_falcon_rd32(falcon, queue->head_reg);
+	/* has the buffer looped? */
+	if (head < queue->position)
+		queue->position = queue->offset;
+
+	tail = queue->position;
+
+	available = head - tail;
+
+	if (available == 0) {
+		nvkm_warn(subdev, "no message data available\n");
+		return 0;
+	}
+
+	if (size > available) {
+		nvkm_warn(subdev, "message data smaller than read request\n");
+		size = available;
+	}
+
+	nvkm_falcon_read_dmem(priv->falcon, tail, size, 0, data);
+	queue->position += ALIGN(size, QUEUE_ALIGNMENT);
+	return size;
+}
+
+static int
+msg_queue_read(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
+	       struct nvkm_msgqueue_hdr *hdr)
+{
+	const struct nvkm_subdev *subdev = priv->falcon->owner;
+	int ret;
+
+	ret = msg_queue_open(priv, queue);
+	if (ret) {
+		nvkm_error(subdev, "fail to open queue %d\n", queue->index);
+		return ret;
+	}
+
+	if (msg_queue_empty(priv, queue)) {
+		ret = 0;
+		goto close;
+	}
+
+	ret = msg_queue_pop(priv, queue, hdr, HDR_SIZE);
+	if (ret >= 0 && ret != HDR_SIZE)
+		ret = -EINVAL;
+	if (ret < 0) {
+		nvkm_error(subdev, "failed to read message header: %d\n", ret);
+		goto close;
+	}
+
+	if (hdr->size > MSG_BUF_SIZE) {
+		nvkm_error(subdev, "message too big (%d bytes)\n", hdr->size);
+		ret = -ENOSPC;
+		goto close;
+	}
+
+	if (hdr->size > HDR_SIZE) {
+		u32 read_size = hdr->size - HDR_SIZE;
+
+		ret = msg_queue_pop(priv, queue, (hdr + 1), read_size);
+		if (ret >= 0 && ret != read_size)
+			ret = -EINVAL;
+		if (ret < 0) {
+			nvkm_error(subdev, "failed to read message: %d\n", ret);
+			goto close;
+		}
+	}
+
+close:
+	msg_queue_close(priv, queue, (ret >= 0));
+	return ret;
+}
+
+static int
+msgqueue_msg_handle(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_hdr *hdr)
+{
+	const struct nvkm_subdev *subdev = priv->falcon->owner;
+	struct nvkm_msgqueue_seq *seq;
+
+	seq = &priv->seq[hdr->seq_id];
+	if (seq->state != SEQ_STATE_USED && seq->state != SEQ_STATE_CANCELLED) {
+		nvkm_error(subdev, "msg for unknown sequence %d", seq->id);
+		return -EINVAL;
+	}
+
+	if (seq->state == SEQ_STATE_USED) {
+		if (seq->callback)
+			seq->callback(priv, hdr);
+	}
+
+	if (seq->completion)
+		complete(seq->completion);
+
+	msgqueue_seq_release(priv, seq);
+	return 0;
+}
+
+static int
+msgqueue_handle_init_msg(struct nvkm_msgqueue *priv,
+			 struct nvkm_msgqueue_hdr *hdr)
+{
+	struct nvkm_falcon *falcon = priv->falcon;
+	const struct nvkm_subdev *subdev = falcon->owner;
+	const u32 tail_reg = falcon->func->msgq.tail;
+	u32 tail;
+	int ret;
+
+	/*
+	 * Read the message - queues are not initialized yet so we cannot rely
+	 * on msg_queue_read()
+	 */
+	tail = nvkm_falcon_rd32(falcon, tail_reg);
+	nvkm_falcon_read_dmem(falcon, tail, HDR_SIZE, 0, hdr);
+
+	if (hdr->size > MSG_BUF_SIZE) {
+		nvkm_error(subdev, "message too big (%d bytes)\n", hdr->size);
+		return -ENOSPC;
+	}
+
+	nvkm_falcon_read_dmem(falcon, tail + HDR_SIZE, hdr->size - HDR_SIZE, 0,
+			      (hdr + 1));
+
+	tail += ALIGN(hdr->size, QUEUE_ALIGNMENT);
+	nvkm_falcon_wr32(falcon, tail_reg, tail);
+
+	ret = priv->func->init_func->init_callback(priv, hdr);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+void
+nvkm_msgqueue_process_msgs(struct nvkm_msgqueue *priv,
+			   struct nvkm_msgqueue_queue *queue)
+{
+	/*
+	 * We are invoked from a worker thread, so normally we have plenty of
+	 * stack space to work with.
+	 */
+	u8 msg_buffer[MSG_BUF_SIZE];
+	struct nvkm_msgqueue_hdr *hdr = (void *)msg_buffer;
+	int ret;
+
+	/* the first message we receive must be the init message */
+	if ((!priv->init_msg_received)) {
+		ret = msgqueue_handle_init_msg(priv, hdr);
+		if (!ret)
+			priv->init_msg_received = true;
+	} else {
+		while (msg_queue_read(priv, queue, hdr) > 0)
+			msgqueue_msg_handle(priv, hdr);
+	}
+}

drivers/gpu/drm/nouveau/nvkm/falcon/msgqueue.c

@@ -26,416 +26,6 @@
 
 #include <subdev/secboot.h>
 
-
-#define HDR_SIZE sizeof(struct nvkm_msgqueue_hdr)
-#define QUEUE_ALIGNMENT 4
-/* max size of the messages we can receive */
-#define MSG_BUF_SIZE 128
-
-static int
-msg_queue_open(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-
-	mutex_lock(&queue->mutex);
-
-	queue->position = nvkm_falcon_rd32(falcon, queue->tail_reg);
-
-	return 0;
-}
-
-static void
-msg_queue_close(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
-		bool commit)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-
-	if (commit)
-		nvkm_falcon_wr32(falcon, queue->tail_reg, queue->position);
-
-	mutex_unlock(&queue->mutex);
-}
-
-static bool
-msg_queue_empty(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-	u32 head, tail;
-
-	head = nvkm_falcon_rd32(falcon, queue->head_reg);
-	tail = nvkm_falcon_rd32(falcon, queue->tail_reg);
-
-	return head == tail;
-}
-
-static int
-msg_queue_pop(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
-	      void *data, u32 size)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-	const struct nvkm_subdev *subdev = priv->falcon->owner;
-	u32 head, tail, available;
-
-	head = nvkm_falcon_rd32(falcon, queue->head_reg);
-	/* has the buffer looped? */
-	if (head < queue->position)
-		queue->position = queue->offset;
-
-	tail = queue->position;
-
-	available = head - tail;
-
-	if (available == 0) {
-		nvkm_warn(subdev, "no message data available\n");
-		return 0;
-	}
-
-	if (size > available) {
-		nvkm_warn(subdev, "message data smaller than read request\n");
-		size = available;
-	}
-
-	nvkm_falcon_read_dmem(priv->falcon, tail, size, 0, data);
-	queue->position += ALIGN(size, QUEUE_ALIGNMENT);
-
-	return size;
-}
-
-static int
-msg_queue_read(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
-	       struct nvkm_msgqueue_hdr *hdr)
-{
-	const struct nvkm_subdev *subdev = priv->falcon->owner;
-	int err;
-
-	err = msg_queue_open(priv, queue);
-	if (err) {
-		nvkm_error(subdev, "fail to open queue %d\n", queue->index);
-		return err;
-	}
-
-	if (msg_queue_empty(priv, queue)) {
-		err = 0;
-		goto close;
-	}
-
-	err = msg_queue_pop(priv, queue, hdr, HDR_SIZE);
-	if (err >= 0 && err != HDR_SIZE)
-		err = -EINVAL;
-	if (err < 0) {
-		nvkm_error(subdev, "failed to read message header: %d\n", err);
-		goto close;
-	}
-
-	if (hdr->size > MSG_BUF_SIZE) {
-		nvkm_error(subdev, "message too big (%d bytes)\n", hdr->size);
-		err = -ENOSPC;
-		goto close;
-	}
-
-	if (hdr->size > HDR_SIZE) {
-		u32 read_size = hdr->size - HDR_SIZE;
-
-		err = msg_queue_pop(priv, queue, (hdr + 1), read_size);
-		if (err >= 0 && err != read_size)
-			err = -EINVAL;
-		if (err < 0) {
-			nvkm_error(subdev, "failed to read message: %d\n", err);
-			goto close;
-		}
-	}
-
-close:
-	msg_queue_close(priv, queue, (err >= 0));
-
-	return err;
-}
-
-static bool
-cmd_queue_has_room(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
-		   u32 size, bool *rewind)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-	u32 head, tail, free;
-
-	size = ALIGN(size, QUEUE_ALIGNMENT);
-
-	head = nvkm_falcon_rd32(falcon, queue->head_reg);
-	tail = nvkm_falcon_rd32(falcon, queue->tail_reg);
-
-	if (head >= tail) {
-		free = queue->offset + queue->size - head;
-		free -= HDR_SIZE;
-
-		if (size > free) {
-			*rewind = true;
-			head = queue->offset;
-		}
-	}
-
-	if (head < tail)
-		free = tail - head - 1;
-
-	return size <= free;
-}
-
-static int
-cmd_queue_push(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
-	       void *data, u32 size)
-{
-	nvkm_falcon_load_dmem(priv->falcon, data, queue->position, size, 0);
-	queue->position += ALIGN(size, QUEUE_ALIGNMENT);
-
-	return 0;
-}
-
-/* REWIND unit is always 0x00 */
-#define MSGQUEUE_UNIT_REWIND 0x00
-
-static void
-cmd_queue_rewind(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue)
-{
-	const struct nvkm_subdev *subdev = priv->falcon->owner;
-	struct nvkm_msgqueue_hdr cmd;
-	int err;
-
-	cmd.unit_id = MSGQUEUE_UNIT_REWIND;
-	cmd.size = sizeof(cmd);
-	err = cmd_queue_push(priv, queue, &cmd, cmd.size);
-	if (err)
-		nvkm_error(subdev, "queue %d rewind failed\n", queue->index);
-	else
-		nvkm_error(subdev, "queue %d rewinded\n", queue->index);
-
-	queue->position = queue->offset;
-}
-
-static int
-cmd_queue_open(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
-	       u32 size)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-	const struct nvkm_subdev *subdev = priv->falcon->owner;
-	bool rewind = false;
-
-	mutex_lock(&queue->mutex);
-
-	if (!cmd_queue_has_room(priv, queue, size, &rewind)) {
-		nvkm_error(subdev, "queue full\n");
-		mutex_unlock(&queue->mutex);
-		return -EAGAIN;
-	}
-
-	queue->position = nvkm_falcon_rd32(falcon, queue->head_reg);
-
-	if (rewind)
-		cmd_queue_rewind(priv, queue);
-
-	return 0;
-}
-
-static void
-cmd_queue_close(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_queue *queue,
-		bool commit)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-
-	if (commit)
-		nvkm_falcon_wr32(falcon, queue->head_reg, queue->position);
-
-	mutex_unlock(&queue->mutex);
-}
-
-static int
-cmd_write(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_hdr *cmd,
-	  struct nvkm_msgqueue_queue *queue)
-{
-	const struct nvkm_subdev *subdev = priv->falcon->owner;
-	static unsigned timeout = 2000;
-	unsigned long end_jiffies = jiffies + msecs_to_jiffies(timeout);
-	int ret = -EAGAIN;
-	bool commit = true;
-
-	while (ret == -EAGAIN && time_before(jiffies, end_jiffies))
-		ret = cmd_queue_open(priv, queue, cmd->size);
-	if (ret) {
-		nvkm_error(subdev, "pmu_queue_open_write failed\n");
-		return ret;
-	}
-
-	ret = cmd_queue_push(priv, queue, cmd, cmd->size);
-	if (ret) {
-		nvkm_error(subdev, "pmu_queue_push failed\n");
-		commit = false;
-	}
-
-	cmd_queue_close(priv, queue, commit);
-
-	return ret;
-}
-
-static struct nvkm_msgqueue_seq *
-msgqueue_seq_acquire(struct nvkm_msgqueue *priv)
-{
-	const struct nvkm_subdev *subdev = priv->falcon->owner;
-	struct nvkm_msgqueue_seq *seq;
-	u32 index;
-
-	mutex_lock(&priv->seq_lock);
-
-	index = find_first_zero_bit(priv->seq_tbl, NVKM_MSGQUEUE_NUM_SEQUENCES);
-
-	if (index >= NVKM_MSGQUEUE_NUM_SEQUENCES) {
-		nvkm_error(subdev, "no free sequence available\n");
-		mutex_unlock(&priv->seq_lock);
-		return ERR_PTR(-EAGAIN);
-	}
-
-	set_bit(index, priv->seq_tbl);
-
-	mutex_unlock(&priv->seq_lock);
-
-	seq = &priv->seq[index];
-	seq->state = SEQ_STATE_PENDING;
-
-	return seq;
-}
-
-static void
-msgqueue_seq_release(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_seq *seq)
-{
-	/* no need to acquire seq_lock since clear_bit is atomic */
-	seq->state = SEQ_STATE_FREE;
-	seq->callback = NULL;
-	seq->completion = NULL;
-	clear_bit(seq->id, priv->seq_tbl);
-}
-
-/* specifies that we want to know the command status in the answer message */
-#define CMD_FLAGS_STATUS BIT(0)
-/* specifies that we want an interrupt when the answer message is queued */
-#define CMD_FLAGS_INTR BIT(1)
-
-int
-nvkm_msgqueue_post(struct nvkm_msgqueue *priv, enum msgqueue_msg_priority prio,
-		   struct nvkm_msgqueue_hdr *cmd, nvkm_msgqueue_callback cb,
-		   struct completion *completion, bool wait_init)
-{
-	struct nvkm_msgqueue_seq *seq;
-	struct nvkm_msgqueue_queue *queue;
-	int ret;
-
-	if (wait_init && !wait_for_completion_timeout(&priv->init_done,
-					 msecs_to_jiffies(1000)))
-		return -ETIMEDOUT;
-
-	queue = priv->func->cmd_queue(priv, prio);
-	if (IS_ERR(queue))
-		return PTR_ERR(queue);
-
-	seq = msgqueue_seq_acquire(priv);
-	if (IS_ERR(seq))
-		return PTR_ERR(seq);
-
-	cmd->seq_id = seq->id;
-	cmd->ctrl_flags = CMD_FLAGS_STATUS | CMD_FLAGS_INTR;
-
-	seq->callback = cb;
-	seq->state = SEQ_STATE_USED;
-	seq->completion = completion;
-
-	ret = cmd_write(priv, cmd, queue);
-	if (ret) {
-		seq->state = SEQ_STATE_PENDING;
-		msgqueue_seq_release(priv, seq);
-	}
-
-	return ret;
-}
-
-static int
-msgqueue_msg_handle(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_hdr *hdr)
-{
-	const struct nvkm_subdev *subdev = priv->falcon->owner;
-	struct nvkm_msgqueue_seq *seq;
-
-	seq = &priv->seq[hdr->seq_id];
-	if (seq->state != SEQ_STATE_USED && seq->state != SEQ_STATE_CANCELLED) {
-		nvkm_error(subdev, "msg for unknown sequence %d", seq->id);
-		return -EINVAL;
-	}
-
-	if (seq->state == SEQ_STATE_USED) {
-		if (seq->callback)
-			seq->callback(priv, hdr);
-	}
-
-	if (seq->completion)
-		complete(seq->completion);
-
-	msgqueue_seq_release(priv, seq);
-
-	return 0;
-}
-
-static int
-msgqueue_handle_init_msg(struct nvkm_msgqueue *priv,
-			 struct nvkm_msgqueue_hdr *hdr)
-{
-	struct nvkm_falcon *falcon = priv->falcon;
-	const struct nvkm_subdev *subdev = falcon->owner;
-	const u32 tail_reg = falcon->func->msgq.tail;
-	u32 tail;
-	int ret;
-
-	/*
-	 * Read the message - queues are not initialized yet so we cannot rely
-	 * on msg_queue_read()
-	 */
-	tail = nvkm_falcon_rd32(falcon, tail_reg);
-	nvkm_falcon_read_dmem(falcon, tail, HDR_SIZE, 0, hdr);
-
-	if (hdr->size > MSG_BUF_SIZE) {
-		nvkm_error(subdev, "message too big (%d bytes)\n", hdr->size);
-		return -ENOSPC;
-	}
-
-	nvkm_falcon_read_dmem(falcon, tail + HDR_SIZE, hdr->size - HDR_SIZE, 0,
-			      (hdr + 1));
-
-	tail += ALIGN(hdr->size, QUEUE_ALIGNMENT);
-	nvkm_falcon_wr32(falcon, tail_reg, tail);
-
-	ret = priv->func->init_func->init_callback(priv, hdr);
-	if (ret)
-		return ret;
-
-	return 0;
-}
-
-void
-nvkm_msgqueue_process_msgs(struct nvkm_msgqueue *priv,
-			   struct nvkm_msgqueue_queue *queue)
-{
-	/*
-	 * We are invoked from a worker thread, so normally we have plenty of
-	 * stack space to work with.
-	 */
-	u8 msg_buffer[MSG_BUF_SIZE];
-	struct nvkm_msgqueue_hdr *hdr = (void *)msg_buffer;
-	int ret;
-
-	/* the first message we receive must be the init message */
-	if ((!priv->init_msg_received)) {
-		ret = msgqueue_handle_init_msg(priv, hdr);
-		if (!ret)
-			priv->init_msg_received = true;
-	} else {
-		while (msg_queue_read(priv, queue, hdr) > 0)
-			msgqueue_msg_handle(priv, hdr);
-	}
-}
-
 void
 nvkm_msgqueue_write_cmdline(struct nvkm_msgqueue *queue, void *buf)
 {

drivers/gpu/drm/nouveau/nvkm/falcon/qmgr.c

+/*
+ * Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved.
+ *
+ * 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 "qmgr.h"
+
+struct nvkm_msgqueue_seq *
+msgqueue_seq_acquire(struct nvkm_msgqueue *priv)
+{
+	const struct nvkm_subdev *subdev = priv->falcon->owner;
+	struct nvkm_msgqueue_seq *seq;
+	u32 index;
+
+	mutex_lock(&priv->seq_lock);
+	index = find_first_zero_bit(priv->seq_tbl, NVKM_MSGQUEUE_NUM_SEQUENCES);
+	if (index >= NVKM_MSGQUEUE_NUM_SEQUENCES) {
+		nvkm_error(subdev, "no free sequence available\n");
+		mutex_unlock(&priv->seq_lock);
+		return ERR_PTR(-EAGAIN);
+	}
+
+	set_bit(index, priv->seq_tbl);
+	mutex_unlock(&priv->seq_lock);
+
+	seq = &priv->seq[index];
+	seq->state = SEQ_STATE_PENDING;
+	return seq;
+}
+
+void
+msgqueue_seq_release(struct nvkm_msgqueue *priv, struct nvkm_msgqueue_seq *seq)
+{
+	/* no need to acquire seq_lock since clear_bit is atomic */
+	seq->state = SEQ_STATE_FREE;
+	seq->callback = NULL;
+	seq->completion = NULL;
+	clear_bit(seq->id, priv->seq_tbl);
+}

drivers/gpu/drm/nouveau/nvkm/falcon/qmgr.h

+/* SPDX-License-Identifier: MIT */
+#ifndef __NVKM_FALCON_QMGR_H__
+#define __NVKM_FALCON_QMGR_H__
+#include <core/falcon.h>
+#include "msgqueue.h"
+
+#define HDR_SIZE sizeof(struct nvkm_msgqueue_hdr)
+#define QUEUE_ALIGNMENT 4
+/* max size of the messages we can receive */
+#define MSG_BUF_SIZE 128
+
+struct nvkm_msgqueue_seq *msgqueue_seq_acquire(struct nvkm_msgqueue *);
+void msgqueue_seq_release(struct nvkm_msgqueue *, struct nvkm_msgqueue_seq *);
+#endif