drm/msm: Conversion to drm scheduler

For existing adrenos, there is one or more ringbuffer, depending on
whether preemption is supported.  When preemption is supported, each
ringbuffer has it's own priority.  A submitqueue (which maps to a
gl context or vk queue in userspace) is mapped to a specific ring-
buffer at creation time, based on the submitqueue's priority.

Each ringbuffer has it's own drm_gpu_scheduler.  Each submitqueue
maps to a drm_sched_entity.  And each submit maps to a drm_sched_job.

Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/4
Signed-off-by: Rob Clark <[email protected]>
Acked-by: Christian König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Clark <[email protected]>

Author: robclark

drivers/gpu/drm/msm/Kconfig

@@ -14,6 +14,7 @@ config DRM_MSM
 	select REGULATOR
 	select DRM_KMS_HELPER
 	select DRM_PANEL
+	select DRM_SCHED
 	select SHMEM
 	select TMPFS
 	select QCOM_SCM if ARCH_QCOM

drivers/gpu/drm/msm/msm_gem.c

@@ -804,41 +804,6 @@ void msm_gem_vunmap(struct drm_gem_object *obj)
 	msm_obj->vaddr = NULL;
 }
 
-/* must be called before _move_to_active().. */
-int msm_gem_sync_object(struct drm_gem_object *obj,
-		struct msm_fence_context *fctx, bool exclusive)
-{
-	struct dma_resv_list *fobj;
-	struct dma_fence *fence;
-	int i, ret;
-
-	fobj = dma_resv_shared_list(obj->resv);
-	if (!fobj || (fobj->shared_count == 0)) {
-		fence = dma_resv_excl_fence(obj->resv);
-		/* don't need to wait on our own fences, since ring is fifo */
-		if (fence && (fence->context != fctx->context)) {
-			ret = dma_fence_wait(fence, true);
-			if (ret)
-				return ret;
-		}
-	}
-
-	if (!exclusive || !fobj)
-		return 0;
-
-	for (i = 0; i < fobj->shared_count; i++) {
-		fence = rcu_dereference_protected(fobj->shared[i],
-						dma_resv_held(obj->resv));
-		if (fence->context != fctx->context) {
-			ret = dma_fence_wait(fence, true);
-			if (ret)
-				return ret;
-		}
-	}
-
-	return 0;
-}
-
 void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu)
 {
 	struct msm_gem_object *msm_obj = to_msm_bo(obj);

drivers/gpu/drm/msm/msm_gem.h

@@ -9,6 +9,7 @@
 
 #include <linux/kref.h>
 #include <linux/dma-resv.h>
+#include "drm/gpu_scheduler.h"
 #include "msm_drv.h"
 
 /* Make all GEM related WARN_ON()s ratelimited.. when things go wrong they
@@ -143,8 +144,6 @@ void *msm_gem_get_vaddr_active(struct drm_gem_object *obj);
 void msm_gem_put_vaddr_locked(struct drm_gem_object *obj);
 void msm_gem_put_vaddr(struct drm_gem_object *obj);
 int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv);
-int msm_gem_sync_object(struct drm_gem_object *obj,
-		struct msm_fence_context *fctx, bool exclusive);
 void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu);
 void msm_gem_active_put(struct drm_gem_object *obj);
 int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout);
@@ -311,6 +310,7 @@ void msm_gem_vunmap(struct drm_gem_object *obj);
  * make it easier to unwind when things go wrong, etc).
  */
 struct msm_gem_submit {
+	struct drm_sched_job base;
 	struct kref ref;
 	struct drm_device *dev;
 	struct msm_gpu *gpu;
@@ -319,7 +319,22 @@ struct msm_gem_submit {
 	struct list_head bo_list;
 	struct ww_acquire_ctx ticket;
 	uint32_t seqno;		/* Sequence number of the submit on the ring */
-	struct dma_fence *fence;
+
+	/* Array of struct dma_fence * to block on before submitting this job.
+	 */
+	struct xarray deps;
+	unsigned long last_dep;
+
+	/* Hw fence, which is created when the scheduler executes the job, and
+	 * is signaled when the hw finishes (via seqno write from cmdstream)
+	 */
+	struct dma_fence *hw_fence;
+
+	/* Userspace visible fence, which is signaled by the scheduler after
+	 * the hw_fence is signaled.
+	 */
+	struct dma_fence *user_fence;
+
 	int fence_id;       /* key into queue->fence_idr */
 	struct msm_gpu_submitqueue *queue;
 	struct pid *pid;    /* submitting process */
@@ -350,6 +365,11 @@ struct msm_gem_submit {
 	} bos[];
 };
 
+static inline struct msm_gem_submit *to_msm_submit(struct drm_sched_job *job)
+{
+	return container_of(job, struct msm_gem_submit, base);
+}
+
 void __msm_gem_submit_destroy(struct kref *kref);
 
 static inline void msm_gem_submit_get(struct msm_gem_submit *submit)