1 files changed, 441 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
new file mode 100644
index 000000000000..88217185e0f3
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
@@ -0,0 +1,441 @@
+// SPDX-License-Identifier: MIT
+
+#include <linux/slab.h>
+#include <drm/gpu_scheduler.h>
+#include <drm/drm_syncobj.h>
+
+#include "nouveau_drv.h"
+#include "nouveau_gem.h"
+#include "nouveau_mem.h"
+#include "nouveau_dma.h"
+#include "nouveau_exec.h"
+#include "nouveau_abi16.h"
+#include "nouveau_sched.h"
+
+/* FIXME
+ *
+ * We want to make sure that jobs currently executing can't be deferred by
+ * other jobs competing for the hardware. Otherwise we might end up with job
+ * timeouts just because of too many clients submitting too many jobs. We don't
+ * want jobs to time out because of system load, but because of the job being
+ * too bulky.
+ *
+ * For now allow for up to 16 concurrent jobs in flight until we know how many
+ * rings the hardware can process in parallel.
+ */
+#define NOUVEAU_SCHED_HW_SUBMISSIONS		16
+#define NOUVEAU_SCHED_JOB_TIMEOUT_MS		10000
+
+int
+nouveau_job_init(struct nouveau_job *job,
+		 struct nouveau_job_args *args)
+{
+	struct nouveau_sched_entity *entity = args->sched_entity;
+	int ret;
+
+	job->file_priv = args->file_priv;
+	job->cli = nouveau_cli(args->file_priv);
+	job->entity = entity;
+
+	job->sync = args->sync;
+	job->resv_usage = args->resv_usage;
+
+	job->ops = args->ops;
+
+	job->in_sync.count = args->in_sync.count;
+	if (job->in_sync.count) {
+		if (job->sync)
+			return -EINVAL;
+
+		job->in_sync.data = kmemdup(args->in_sync.s,
+					 sizeof(*args->in_sync.s) *
+					 args->in_sync.count,
+					 GFP_KERNEL);
+		if (!job->in_sync.data)
+			return -ENOMEM;
+	}
+
+	job->out_sync.count = args->out_sync.count;
+	if (job->out_sync.count) {
+		if (job->sync) {
+			ret = -EINVAL;
+			goto err_free_in_sync;
+		}
+
+		job->out_sync.data = kmemdup(args->out_sync.s,
+					  sizeof(*args->out_sync.s) *
+					  args->out_sync.count,
+					  GFP_KERNEL);
+		if (!job->out_sync.data) {
+			ret = -ENOMEM;
+			goto err_free_in_sync;
+		}
+
+		job->out_sync.objs = kcalloc(job->out_sync.count,
+					     sizeof(*job->out_sync.objs),
+					     GFP_KERNEL);
+		if (!job->out_sync.objs) {
+			ret = -ENOMEM;
+			goto err_free_out_sync;
+		}
+
+		job->out_sync.chains = kcalloc(job->out_sync.count,
+					       sizeof(*job->out_sync.chains),
+					       GFP_KERNEL);
+		if (!job->out_sync.chains) {
+			ret = -ENOMEM;
+			goto err_free_objs;
+		}
+
+	}
+
+	ret = drm_sched_job_init(&job->base, &entity->base, NULL);
+	if (ret)
+		goto err_free_chains;
+
+	job->state = NOUVEAU_JOB_INITIALIZED;
+
+	return 0;
+
+err_free_chains:
+	kfree(job->out_sync.chains);
+err_free_objs:
+	kfree(job->out_sync.objs);
+err_free_out_sync:
+	kfree(job->out_sync.data);
+err_free_in_sync:
+	kfree(job->in_sync.data);
+return ret;
+}
+
+void
+nouveau_job_free(struct nouveau_job *job)
+{
+	kfree(job->in_sync.data);
+	kfree(job->out_sync.data);
+	kfree(job->out_sync.objs);
+	kfree(job->out_sync.chains);
+}
+
+void nouveau_job_fini(struct nouveau_job *job)
+{
+	dma_fence_put(job->done_fence);
+	drm_sched_job_cleanup(&job->base);
+	job->ops->free(job);
+}
+
+static int
+sync_find_fence(struct nouveau_job *job,
+		struct drm_nouveau_sync *sync,
+		struct dma_fence **fence)
+{
+	u32 stype = sync->flags & DRM_NOUVEAU_SYNC_TYPE_MASK;
+	u64 point = 0;
+	int ret;
+
+	if (stype != DRM_NOUVEAU_SYNC_SYNCOBJ &&
+	    stype != DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ)
+		return -EOPNOTSUPP;
+
+	if (stype == DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ)
+		point = sync->timeline_value;
+
+	ret = drm_syncobj_find_fence(job->file_priv,
+				     sync->handle, point,
+				     0 /* flags */, fence);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int
+nouveau_job_add_deps(struct nouveau_job *job)
+{
+	struct dma_fence *in_fence = NULL;
+	int ret, i;
+
+	for (i = 0; i < job->in_sync.count; i++) {
+		struct drm_nouveau_sync *sync = &job->in_sync.data[i];
+
+		ret = sync_find_fence(job, sync, &in_fence);
+		if (ret) {
+			NV_PRINTK(warn, job->cli,
+				  "Failed to find syncobj (-> in): handle=%d\n",
+				  sync->handle);
+			return ret;
+		}
+
+		ret = drm_sched_job_add_dependency(&job->base, in_fence);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static void
+nouveau_job_fence_attach_cleanup(struct nouveau_job *job)
+{
+	int i;
+
+	for (i = 0; i < job->out_sync.count; i++) {
+		struct drm_syncobj *obj = job->out_sync.objs[i];
+		struct dma_fence_chain *chain = job->out_sync.chains[i];
+
+		if (obj)
+			drm_syncobj_put(obj);
+
+		if (chain)
+			dma_fence_chain_free(chain);
+	}
+}
+
+static int
+nouveau_job_fence_attach_prepare(struct nouveau_job *job)
+{
+	int i, ret;
+
+	for (i = 0; i < job->out_sync.count; i++) {
+		struct drm_nouveau_sync *sync = &job->out_sync.data[i];
+		struct drm_syncobj **pobj = &job->out_sync.objs[i];
+		struct dma_fence_chain **pchain = &job->out_sync.chains[i];
+		u32 stype = sync->flags & DRM_NOUVEAU_SYNC_TYPE_MASK;
+
+		if (stype != DRM_NOUVEAU_SYNC_SYNCOBJ &&
+		    stype != DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ) {
+			ret = -EINVAL;
+			goto err_sync_cleanup;
+		}
+
+		*pobj = drm_syncobj_find(job->file_priv, sync->handle);
+		if (!*pobj) {
+			NV_PRINTK(warn, job->cli,
+				  "Failed to find syncobj (-> out): handle=%d\n",
+				  sync->handle);
+			ret = -ENOENT;
+			goto err_sync_cleanup;
+		}
+
+		if (stype == DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ) {
+			*pchain = dma_fence_chain_alloc();
+			if (!*pchain) {
+				ret = -ENOMEM;
+				goto err_sync_cleanup;
+			}
+		}
+	}
+
+	return 0;
+
+err_sync_cleanup:
+	nouveau_job_fence_attach_cleanup(job);
+	return ret;
+}
+
+static void
+nouveau_job_fence_attach(struct nouveau_job *job)
+{
+	struct dma_fence *fence = job->done_fence;
+	int i;
+
+	for (i = 0; i < job->out_sync.count; i++) {
+		struct drm_nouveau_sync *sync = &job->out_sync.data[i];
+		struct drm_syncobj **pobj = &job->out_sync.objs[i];
+		struct dma_fence_chain **pchain = &job->out_sync.chains[i];
+		u32 stype = sync->flags & DRM_NOUVEAU_SYNC_TYPE_MASK;
+
+		if (stype == DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ) {
+			drm_syncobj_add_point(*pobj, *pchain, fence,
+					      sync->timeline_value);
+		} else {
+			drm_syncobj_replace_fence(*pobj, fence);
+		}
+
+		drm_syncobj_put(*pobj);
+		*pobj = NULL;
+		*pchain = NULL;
+	}
+}
+
+int
+nouveau_job_submit(struct nouveau_job *job)
+{
+	struct nouveau_sched_entity *entity = to_nouveau_sched_entity(job->base.entity);
+	struct dma_fence *done_fence = NULL;
+	int ret;
+
+	ret = nouveau_job_add_deps(job);
+	if (ret)
+		goto err;
+
+	ret = nouveau_job_fence_attach_prepare(job);
+	if (ret)
+		goto err;
+
+	/* Make sure the job appears on the sched_entity's queue in the same
+	 * order as it was submitted.
+	 */
+	mutex_lock(&entity->mutex);
+
+	/* Guarantee we won't fail after the submit() callback returned
+	 * successfully.
+	 */
+	if (job->ops->submit) {
+		ret = job->ops->submit(job);
+		if (ret)
+			goto err_cleanup;
+	}
+
+	drm_sched_job_arm(&job->base);
+	job->done_fence = dma_fence_get(&job->base.s_fence->finished);
+	if (job->sync)
+		done_fence = dma_fence_get(job->done_fence);
+
+	/* If a sched job depends on a dma-fence from a job from the same GPU
+	 * scheduler instance, but a different scheduler entity, the GPU
+	 * scheduler does only wait for the particular job to be scheduled,
+	 * rather than for the job to fully complete. This is due to the GPU
+	 * scheduler assuming that there is a scheduler instance per ring.
+	 * However, the current implementation, in order to avoid arbitrary
+	 * amounts of kthreads, has a single scheduler instance while scheduler
+	 * entities represent rings.
+	 *
+	 * As a workaround, set the DRM_SCHED_FENCE_DONT_PIPELINE for all
+	 * out-fences in order to force the scheduler to wait for full job
+	 * completion for dependent jobs from different entities and same
+	 * scheduler instance.
+	 *
+	 * There is some work in progress [1] to address the issues of firmware
+	 * schedulers; once it is in-tree the scheduler topology in Nouveau
+	 * should be re-worked accordingly.
+	 *
+	 * [1] https://lore.kernel.org/dri-devel/20230801205103.627779-1-matthew.brost@intel.com/
+	 */
+	set_bit(DRM_SCHED_FENCE_DONT_PIPELINE, &job->done_fence->flags);
+
+	if (job->ops->armed_submit)
+		job->ops->armed_submit(job);
+
+	nouveau_job_fence_attach(job);
+
+	/* Set job state before pushing the job to the scheduler,
+	 * such that we do not overwrite the job state set in run().
+	 */
+	job->state = NOUVEAU_JOB_SUBMIT_SUCCESS;
+
+	drm_sched_entity_push_job(&job->base);
+
+	mutex_unlock(&entity->mutex);
+
+	if (done_fence) {
+		dma_fence_wait(done_fence, true);
+		dma_fence_put(done_fence);
+	}
+
+	return 0;
+
+err_cleanup:
+	mutex_unlock(&entity->mutex);
+	nouveau_job_fence_attach_cleanup(job);
+err:
+	job->state = NOUVEAU_JOB_SUBMIT_FAILED;
+	return ret;
+}
+
+bool
+nouveau_sched_entity_qwork(struct nouveau_sched_entity *entity,
+			   struct work_struct *work)
+{
+	return queue_work(entity->sched_wq, work);
+}
+
+static struct dma_fence *
+nouveau_job_run(struct nouveau_job *job)
+{
+	struct dma_fence *fence;
+
+	fence = job->ops->run(job);
+	if (IS_ERR(fence))
+		job->state = NOUVEAU_JOB_RUN_FAILED;
+	else
+		job->state = NOUVEAU_JOB_RUN_SUCCESS;
+
+	return fence;
+}
+
+static struct dma_fence *
+nouveau_sched_run_job(struct drm_sched_job *sched_job)
+{
+	struct nouveau_job *job = to_nouveau_job(sched_job);
+
+	return nouveau_job_run(job);
+}
+
+static enum drm_gpu_sched_stat
+nouveau_sched_timedout_job(struct drm_sched_job *sched_job)
+{
+	struct nouveau_job *job = to_nouveau_job(sched_job);
+
+	NV_PRINTK(warn, job->cli, "Job timed out.\n");
+
+	if (job->ops->timeout)
+		return job->ops->timeout(job);
+
+	return DRM_GPU_SCHED_STAT_ENODEV;
+}
+
+static void
+nouveau_sched_free_job(struct drm_sched_job *sched_job)
+{
+	struct nouveau_job *job = to_nouveau_job(sched_job);
+
+	nouveau_job_fini(job);
+}
+
+int nouveau_sched_entity_init(struct nouveau_sched_entity *entity,
+			      struct drm_gpu_scheduler *sched,
+			      struct workqueue_struct *sched_wq)
+{
+	mutex_init(&entity->mutex);
+	spin_lock_init(&entity->job.list.lock);
+	INIT_LIST_HEAD(&entity->job.list.head);
+	init_waitqueue_head(&entity->job.wq);
+
+	entity->sched_wq = sched_wq;
+	return drm_sched_entity_init(&entity->base,
+				     DRM_SCHED_PRIORITY_NORMAL,
+				     &sched, 1, NULL);
+}
+
+void
+nouveau_sched_entity_fini(struct nouveau_sched_entity *entity)
+{
+	drm_sched_entity_destroy(&entity->base);
+}
+
+static const struct drm_sched_backend_ops nouveau_sched_ops = {
+	.run_job = nouveau_sched_run_job,
+	.timedout_job = nouveau_sched_timedout_job,
+	.free_job = nouveau_sched_free_job,
+};
+
+int nouveau_sched_init(struct nouveau_drm *drm)
+{
+	struct drm_gpu_scheduler *sched = &drm->sched;
+	long job_hang_limit = msecs_to_jiffies(NOUVEAU_SCHED_JOB_TIMEOUT_MS);
+
+	drm->sched_wq = create_singlethread_workqueue("nouveau_sched_wq");
+	if (!drm->sched_wq)
+		return -ENOMEM;
+
+	return drm_sched_init(sched, &nouveau_sched_ops,
+			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
+			      NULL, NULL, "nouveau_sched", drm->dev->dev);
+}
+
+void nouveau_sched_fini(struct nouveau_drm *drm)
+{
+	destroy_workqueue(drm->sched_wq);
+	drm_sched_fini(&drm->sched);
+}