accel/ivpu: Add command buffer submission logic

Each of the user contexts has two command queues, one for compute engine
and one for the copy engine. Command queues are allocated and registered
in the device when the first job (command buffer) is submitted from
the user space to the VPU device. The userspace provides a list of
GEM buffer object handles to submit to the VPU, the driver resolves
buffer handles, pins physical memory if needed, increments ref count
for each buffer and stores pointers to buffer objects in
the ivpu_job objects that track jobs submitted to the device.
The VPU signals job completion with an asynchronous message that
contains the job id passed to firmware when the job was submitted.

Currently, the driver supports simple scheduling logic
where jobs submitted from user space are immediately pushed
to the VPU device command queues. In the future, it will be
extended to use hardware base scheduling and/or drm_sched.

Co-developed-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>
Signed-off-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20230117092723.60441-7-jacek.lawrynowicz@linux.intel.com

1 files changed, 602 insertions, 0 deletions

diff --git a/drivers/accel/ivpu/ivpu_job.c b/drivers/accel/ivpu/ivpu_job.c
new file mode 100644
index 000000000000..23cdb3b3f1f3
--- /dev/null
+++ b/drivers/accel/ivpu/ivpu_job.c
@@ -0,0 +1,602 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020-2023 Intel Corporation
+ */
+
+#include <drm/drm_file.h>
+
+#include <linux/bitfield.h>
+#include <linux/highmem.h>
+#include <linux/kthread.h>
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <uapi/drm/ivpu_accel.h>
+
+#include "ivpu_drv.h"
+#include "ivpu_hw.h"
+#include "ivpu_ipc.h"
+#include "ivpu_job.h"
+#include "ivpu_jsm_msg.h"
+
+#define CMD_BUF_IDX	     0
+#define JOB_ID_JOB_MASK	     GENMASK(7, 0)
+#define JOB_ID_CONTEXT_MASK  GENMASK(31, 8)
+#define JOB_MAX_BUFFER_COUNT 65535
+
+static unsigned int ivpu_tdr_timeout_ms;
+module_param_named(tdr_timeout_ms, ivpu_tdr_timeout_ms, uint, 0644);
+MODULE_PARM_DESC(tdr_timeout_ms, "Timeout for device hang detection, in milliseconds, 0 - default");
+
+static void ivpu_cmdq_ring_db(struct ivpu_device *vdev, struct ivpu_cmdq *cmdq)
+{
+	ivpu_hw_reg_db_set(vdev, cmdq->db_id);
+}
+
+static struct ivpu_cmdq *ivpu_cmdq_alloc(struct ivpu_file_priv *file_priv, u16 engine)
+{
+	struct ivpu_device *vdev = file_priv->vdev;
+	struct vpu_job_queue_header *jobq_header;
+	struct ivpu_cmdq *cmdq;
+
+	cmdq = kzalloc(sizeof(*cmdq), GFP_KERNEL);
+	if (!cmdq)
+		return NULL;
+
+	cmdq->mem = ivpu_bo_alloc_internal(vdev, 0, SZ_4K, DRM_IVPU_BO_WC);
+	if (!cmdq->mem)
+		goto cmdq_free;
+
+	cmdq->db_id = file_priv->ctx.id + engine * ivpu_get_context_count(vdev);
+	cmdq->entry_count = (u32)((cmdq->mem->base.size - sizeof(struct vpu_job_queue_header)) /
+				  sizeof(struct vpu_job_queue_entry));
+
+	cmdq->jobq = (struct vpu_job_queue *)cmdq->mem->kvaddr;
+	jobq_header = &cmdq->jobq->header;
+	jobq_header->engine_idx = engine;
+	jobq_header->head = 0;
+	jobq_header->tail = 0;
+	wmb(); /* Flush WC buffer for jobq->header */
+
+	return cmdq;
+
+cmdq_free:
+	kfree(cmdq);
+	return NULL;
+}
+
+static void ivpu_cmdq_free(struct ivpu_file_priv *file_priv, struct ivpu_cmdq *cmdq)
+{
+	if (!cmdq)
+		return;
+
+	ivpu_bo_free_internal(cmdq->mem);
+	kfree(cmdq);
+}
+
+static struct ivpu_cmdq *ivpu_cmdq_acquire(struct ivpu_file_priv *file_priv, u16 engine)
+{
+	struct ivpu_device *vdev = file_priv->vdev;
+	struct ivpu_cmdq *cmdq = file_priv->cmdq[engine];
+	int ret;
+
+	lockdep_assert_held(&file_priv->lock);
+
+	if (!cmdq) {
+		cmdq = ivpu_cmdq_alloc(file_priv, engine);
+		if (!cmdq)
+			return NULL;
+		file_priv->cmdq[engine] = cmdq;
+	}
+
+	if (cmdq->db_registered)
+		return cmdq;
+
+	ret = ivpu_jsm_register_db(vdev, file_priv->ctx.id, cmdq->db_id,
+				   cmdq->mem->vpu_addr, cmdq->mem->base.size);
+	if (ret)
+		return NULL;
+
+	cmdq->db_registered = true;
+
+	return cmdq;
+}
+
+static void ivpu_cmdq_release_locked(struct ivpu_file_priv *file_priv, u16 engine)
+{
+	struct ivpu_cmdq *cmdq = file_priv->cmdq[engine];
+
+	lockdep_assert_held(&file_priv->lock);
+
+	if (cmdq) {
+		file_priv->cmdq[engine] = NULL;
+		if (cmdq->db_registered)
+			ivpu_jsm_unregister_db(file_priv->vdev, cmdq->db_id);
+
+		ivpu_cmdq_free(file_priv, cmdq);
+	}
+}
+
+void ivpu_cmdq_release_all(struct ivpu_file_priv *file_priv)
+{
+	int i;
+
+	mutex_lock(&file_priv->lock);
+
+	for (i = 0; i < IVPU_NUM_ENGINES; i++)
+		ivpu_cmdq_release_locked(file_priv, i);
+
+	mutex_unlock(&file_priv->lock);
+}
+
+/*
+ * Mark the doorbell as unregistered and reset job queue pointers.
+ * This function needs to be called when the VPU hardware is restarted
+ * and FW looses job queue state. The next time job queue is used it
+ * will be registered again.
+ */
+static void ivpu_cmdq_reset_locked(struct ivpu_file_priv *file_priv, u16 engine)
+{
+	struct ivpu_cmdq *cmdq = file_priv->cmdq[engine];
+
+	lockdep_assert_held(&file_priv->lock);
+
+	if (cmdq) {
+		cmdq->db_registered = false;
+		cmdq->jobq->header.head = 0;
+		cmdq->jobq->header.tail = 0;
+		wmb(); /* Flush WC buffer for jobq header */
+	}
+}
+
+static void ivpu_cmdq_reset_all(struct ivpu_file_priv *file_priv)
+{
+	int i;
+
+	mutex_lock(&file_priv->lock);
+
+	for (i = 0; i < IVPU_NUM_ENGINES; i++)
+		ivpu_cmdq_reset_locked(file_priv, i);
+
+	mutex_unlock(&file_priv->lock);
+}
+
+void ivpu_cmdq_reset_all_contexts(struct ivpu_device *vdev)
+{
+	struct ivpu_file_priv *file_priv;
+	unsigned long ctx_id;
+
+	xa_for_each(&vdev->context_xa, ctx_id, file_priv) {
+		file_priv = ivpu_file_priv_get_by_ctx_id(vdev, ctx_id);
+		if (!file_priv)
+			continue;
+
+		ivpu_cmdq_reset_all(file_priv);
+
+		ivpu_file_priv_put(&file_priv);
+	}
+}
+
+static int ivpu_cmdq_push_job(struct ivpu_cmdq *cmdq, struct ivpu_job *job)
+{
+	struct ivpu_device *vdev = job->vdev;
+	struct vpu_job_queue_header *header = &cmdq->jobq->header;
+	struct vpu_job_queue_entry *entry;
+	u32 tail = READ_ONCE(header->tail);
+	u32 next_entry = (tail + 1) % cmdq->entry_count;
+
+	/* Check if there is space left in job queue */
+	if (next_entry == header->head) {
+		ivpu_dbg(vdev, JOB, "Job queue full: ctx %d engine %d db %d head %d tail %d\n",
+			 job->file_priv->ctx.id, job->engine_idx, cmdq->db_id, header->head, tail);
+		return -EBUSY;
+	}
+
+	entry = &cmdq->jobq->job[tail];
+	entry->batch_buf_addr = job->cmd_buf_vpu_addr;
+	entry->job_id = job->job_id;
+	entry->flags = 0;
+	wmb(); /* Ensure that tail is updated after filling entry */
+	header->tail = next_entry;
+	wmb(); /* Flush WC buffer for jobq header */
+
+	return 0;
+}
+
+struct ivpu_fence {
+	struct dma_fence base;
+	spinlock_t lock; /* protects base */
+	struct ivpu_device *vdev;
+};
+
+static inline struct ivpu_fence *to_vpu_fence(struct dma_fence *fence)
+{
+	return container_of(fence, struct ivpu_fence, base);
+}
+
+static const char *ivpu_fence_get_driver_name(struct dma_fence *fence)
+{
+	return DRIVER_NAME;
+}
+
+static const char *ivpu_fence_get_timeline_name(struct dma_fence *fence)
+{
+	struct ivpu_fence *ivpu_fence = to_vpu_fence(fence);
+
+	return dev_name(ivpu_fence->vdev->drm.dev);
+}
+
+static const struct dma_fence_ops ivpu_fence_ops = {
+	.get_driver_name = ivpu_fence_get_driver_name,
+	.get_timeline_name = ivpu_fence_get_timeline_name,
+};
+
+static struct dma_fence *ivpu_fence_create(struct ivpu_device *vdev)
+{
+	struct ivpu_fence *fence;
+
+	fence = kzalloc(sizeof(*fence), GFP_KERNEL);
+	if (!fence)
+		return NULL;
+
+	fence->vdev = vdev;
+	spin_lock_init(&fence->lock);
+	dma_fence_init(&fence->base, &ivpu_fence_ops, &fence->lock, dma_fence_context_alloc(1), 1);
+
+	return &fence->base;
+}
+
+static void job_get(struct ivpu_job *job, struct ivpu_job **link)
+{
+	struct ivpu_device *vdev = job->vdev;
+
+	kref_get(&job->ref);
+	*link = job;
+
+	ivpu_dbg(vdev, KREF, "Job get: id %u refcount %u\n", job->job_id, kref_read(&job->ref));
+}
+
+static void job_release(struct kref *ref)
+{
+	struct ivpu_job *job = container_of(ref, struct ivpu_job, ref);
+	struct ivpu_device *vdev = job->vdev;
+	u32 i;
+
+	for (i = 0; i < job->bo_count; i++)
+		if (job->bos[i])
+			drm_gem_object_put(&job->bos[i]->base);
+
+	dma_fence_put(job->done_fence);
+	ivpu_file_priv_put(&job->file_priv);
+
+	ivpu_dbg(vdev, KREF, "Job released: id %u\n", job->job_id);
+	kfree(job);
+}
+
+static void job_put(struct ivpu_job *job)
+{
+	struct ivpu_device *vdev = job->vdev;
+
+	ivpu_dbg(vdev, KREF, "Job put: id %u refcount %u\n", job->job_id, kref_read(&job->ref));
+	kref_put(&job->ref, job_release);
+}
+
+static struct ivpu_job *
+ivpu_create_job(struct ivpu_file_priv *file_priv, u32 engine_idx, u32 bo_count)
+{
+	struct ivpu_device *vdev = file_priv->vdev;
+	struct ivpu_job *job;
+	size_t buf_size;
+
+	buf_size = sizeof(*job) + bo_count * sizeof(struct ivpu_bo *);
+	job = kzalloc(buf_size, GFP_KERNEL);
+	if (!job)
+		return NULL;
+
+	kref_init(&job->ref);
+
+	job->vdev = vdev;
+	job->engine_idx = engine_idx;
+	job->bo_count = bo_count;
+	job->done_fence = ivpu_fence_create(vdev);
+	if (!job->done_fence) {
+		ivpu_warn_ratelimited(vdev, "Failed to create a fence\n");
+		goto err_free_job;
+	}
+
+	job->file_priv = ivpu_file_priv_get(file_priv);
+
+	ivpu_dbg(vdev, JOB, "Job created: ctx %2d engine %d", file_priv->ctx.id, job->engine_idx);
+
+	return job;
+
+err_free_job:
+	kfree(job);
+	return NULL;
+}
+
+static int ivpu_job_done(struct ivpu_device *vdev, u32 job_id, u32 job_status)
+{
+	struct ivpu_job *job;
+
+	job = xa_erase(&vdev->submitted_jobs_xa, job_id);
+	if (!job)
+		return -ENOENT;
+
+	if (job->file_priv->has_mmu_faults)
+		job_status = VPU_JSM_STATUS_ABORTED;
+
+	job->bos[CMD_BUF_IDX]->job_status = job_status;
+	dma_fence_signal(job->done_fence);
+
+	ivpu_dbg(vdev, JOB, "Job complete:  id %3u ctx %2d engine %d status 0x%x\n",
+		 job->job_id, job->file_priv->ctx.id, job->engine_idx, job_status);
+
+	job_put(job);
+	return 0;
+}
+
+static void ivpu_job_done_message(struct ivpu_device *vdev, void *msg)
+{
+	struct vpu_ipc_msg_payload_job_done *payload;
+	struct vpu_jsm_msg *job_ret_msg = msg;
+	int ret;
+
+	payload = (struct vpu_ipc_msg_payload_job_done *)&job_ret_msg->payload;
+
+	ret = ivpu_job_done(vdev, payload->job_id, payload->job_status);
+	if (ret)
+		ivpu_err(vdev, "Failed to finish job %d: %d\n", payload->job_id, ret);
+}
+
+void ivpu_jobs_abort_all(struct ivpu_device *vdev)
+{
+	struct ivpu_job *job;
+	unsigned long id;
+
+	xa_for_each(&vdev->submitted_jobs_xa, id, job)
+		ivpu_job_done(vdev, id, VPU_JSM_STATUS_ABORTED);
+}
+
+static int ivpu_direct_job_submission(struct ivpu_job *job)
+{
+	struct ivpu_file_priv *file_priv = job->file_priv;
+	struct ivpu_device *vdev = job->vdev;
+	struct xa_limit job_id_range;
+	struct ivpu_cmdq *cmdq;
+	int ret;
+
+	mutex_lock(&file_priv->lock);
+
+	cmdq = ivpu_cmdq_acquire(job->file_priv, job->engine_idx);
+	if (!cmdq) {
+		ivpu_warn(vdev, "Failed get job queue, ctx %d engine %d\n",
+			  file_priv->ctx.id, job->engine_idx);
+		ret = -EINVAL;
+		goto err_unlock;
+	}
+
+	job_id_range.min = FIELD_PREP(JOB_ID_CONTEXT_MASK, (file_priv->ctx.id - 1));
+	job_id_range.max = job_id_range.min | JOB_ID_JOB_MASK;
+
+	job_get(job, &job);
+	ret = xa_alloc(&vdev->submitted_jobs_xa, &job->job_id, job, job_id_range, GFP_KERNEL);
+	if (ret) {
+		ivpu_warn_ratelimited(vdev, "Failed to allocate job id: %d\n", ret);
+		goto err_job_put;
+	}
+
+	ret = ivpu_cmdq_push_job(cmdq, job);
+	if (ret)
+		goto err_xa_erase;
+
+	ivpu_dbg(vdev, JOB, "Job submitted: id %3u ctx %2d engine %d next %d\n",
+		 job->job_id, file_priv->ctx.id, job->engine_idx, cmdq->jobq->header.tail);
+
+	if (ivpu_test_mode == IVPU_TEST_MODE_NULL_HW) {
+		ivpu_job_done(vdev, job->job_id, VPU_JSM_STATUS_SUCCESS);
+		cmdq->jobq->header.head = cmdq->jobq->header.tail;
+		wmb(); /* Flush WC buffer for jobq header */
+	} else {
+		ivpu_cmdq_ring_db(vdev, cmdq);
+	}
+
+	mutex_unlock(&file_priv->lock);
+	return 0;
+
+err_xa_erase:
+	xa_erase(&vdev->submitted_jobs_xa, job->job_id);
+err_job_put:
+	job_put(job);
+err_unlock:
+	mutex_unlock(&file_priv->lock);
+	return ret;
+}
+
+static int
+ivpu_job_prepare_bos_for_submit(struct drm_file *file, struct ivpu_job *job, u32 *buf_handles,
+				u32 buf_count, u32 commands_offset)
+{
+	struct ivpu_file_priv *file_priv = file->driver_priv;
+	struct ivpu_device *vdev = file_priv->vdev;
+	struct ww_acquire_ctx acquire_ctx;
+	struct ivpu_bo *bo;
+	int ret;
+	u32 i;
+
+	for (i = 0; i < buf_count; i++) {
+		struct drm_gem_object *obj = drm_gem_object_lookup(file, buf_handles[i]);
+
+		if (!obj)
+			return -ENOENT;
+
+		job->bos[i] = to_ivpu_bo(obj);
+
+		ret = ivpu_bo_pin(job->bos[i]);
+		if (ret)
+			return ret;
+	}
+
+	bo = job->bos[CMD_BUF_IDX];
+	if (!dma_resv_test_signaled(bo->base.resv, DMA_RESV_USAGE_READ)) {
+		ivpu_warn(vdev, "Buffer is already in use\n");
+		return -EBUSY;
+	}
+
+	if (commands_offset >= bo->base.size) {
+		ivpu_warn(vdev, "Invalid command buffer offset %u\n", commands_offset);
+		return -EINVAL;
+	}
+
+	job->cmd_buf_vpu_addr = bo->vpu_addr + commands_offset;
+
+	ret = drm_gem_lock_reservations((struct drm_gem_object **)job->bos, buf_count,
+					&acquire_ctx);
+	if (ret) {
+		ivpu_warn(vdev, "Failed to lock reservations: %d\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < buf_count; i++) {
+		ret = dma_resv_reserve_fences(job->bos[i]->base.resv, 1);
+		if (ret) {
+			ivpu_warn(vdev, "Failed to reserve fences: %d\n", ret);
+			goto unlock_reservations;
+		}
+	}
+
+	for (i = 0; i < buf_count; i++)
+		dma_resv_add_fence(job->bos[i]->base.resv, job->done_fence, DMA_RESV_USAGE_WRITE);
+
+unlock_reservations:
+	drm_gem_unlock_reservations((struct drm_gem_object **)job->bos, buf_count, &acquire_ctx);
+
+	wmb(); /* Flush write combining buffers */
+
+	return ret;
+}
+
+int ivpu_submit_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
+{
+	int ret = 0;
+	struct ivpu_file_priv *file_priv = file->driver_priv;
+	struct ivpu_device *vdev = file_priv->vdev;
+	struct drm_ivpu_submit *params = data;
+	struct ivpu_job *job;
+	u32 *buf_handles;
+
+	if (params->engine > DRM_IVPU_ENGINE_COPY)
+		return -EINVAL;
+
+	if (params->buffer_count == 0 || params->buffer_count > JOB_MAX_BUFFER_COUNT)
+		return -EINVAL;
+
+	if (!IS_ALIGNED(params->commands_offset, 8))
+		return -EINVAL;
+
+	if (!file_priv->ctx.id)
+		return -EINVAL;
+
+	if (file_priv->has_mmu_faults)
+		return -EBADFD;
+
+	buf_handles = kcalloc(params->buffer_count, sizeof(u32), GFP_KERNEL);
+	if (!buf_handles)
+		return -ENOMEM;
+
+	ret = copy_from_user(buf_handles,
+			     (void __user *)params->buffers_ptr,
+			     params->buffer_count * sizeof(u32));
+	if (ret) {
+		ret = -EFAULT;
+		goto free_handles;
+	}
+
+	ivpu_dbg(vdev, JOB, "Submit ioctl: ctx %u buf_count %u\n",
+		 file_priv->ctx.id, params->buffer_count);
+
+	job = ivpu_create_job(file_priv, params->engine, params->buffer_count);
+	if (!job) {
+		ivpu_err(vdev, "Failed to create job\n");
+		ret = -ENOMEM;
+		goto free_handles;
+	}
+
+	ret = ivpu_job_prepare_bos_for_submit(file, job, buf_handles, params->buffer_count,
+					      params->commands_offset);
+	if (ret) {
+		ivpu_err(vdev, "Failed to prepare job, ret %d\n", ret);
+		goto job_put;
+	}
+
+	ret = ivpu_direct_job_submission(job);
+	if (ret) {
+		dma_fence_signal(job->done_fence);
+		ivpu_err(vdev, "Failed to submit job to the HW, ret %d\n", ret);
+	}
+
+job_put:
+	job_put(job);
+free_handles:
+	kfree(buf_handles);
+
+	return ret;
+}
+
+static int ivpu_job_done_thread(void *arg)
+{
+	struct ivpu_device *vdev = (struct ivpu_device *)arg;
+	struct ivpu_ipc_consumer cons;
+	struct vpu_jsm_msg jsm_msg;
+	bool jobs_submitted;
+	unsigned int timeout;
+	int ret;
+
+	ivpu_dbg(vdev, JOB, "Started %s\n", __func__);
+
+	ivpu_ipc_consumer_add(vdev, &cons, VPU_IPC_CHAN_JOB_RET);
+
+	while (!kthread_should_stop()) {
+		timeout = ivpu_tdr_timeout_ms ? ivpu_tdr_timeout_ms : vdev->timeout.tdr;
+		jobs_submitted = !xa_empty(&vdev->submitted_jobs_xa);
+		ret = ivpu_ipc_receive(vdev, &cons, NULL, &jsm_msg, timeout);
+		if (!ret) {
+			ivpu_job_done_message(vdev, &jsm_msg);
+		} else if (ret == -ETIMEDOUT) {
+			if (jobs_submitted && !xa_empty(&vdev->submitted_jobs_xa)) {
+				ivpu_err(vdev, "TDR detected, timeout %d ms", timeout);
+				ivpu_hw_diagnose_failure(vdev);
+			}
+		}
+	}
+
+	ivpu_ipc_consumer_del(vdev, &cons);
+
+	ivpu_jobs_abort_all(vdev);
+
+	ivpu_dbg(vdev, JOB, "Stopped %s\n", __func__);
+	return 0;
+}
+
+int ivpu_job_done_thread_init(struct ivpu_device *vdev)
+{
+	struct task_struct *thread;
+
+	thread = kthread_run(&ivpu_job_done_thread, (void *)vdev, "ivpu_job_done_thread");
+	if (IS_ERR(thread)) {
+		ivpu_err(vdev, "Failed to start job completion thread\n");
+		return -EIO;
+	}
+
+	get_task_struct(thread);
+	wake_up_process(thread);
+
+	vdev->job_done_thread = thread;
+
+	return 0;
+}
+
+void ivpu_job_done_thread_fini(struct ivpu_device *vdev)
+{
+	kthread_stop(vdev->job_done_thread);
+	put_task_struct(vdev->job_done_thread);
+}