[PATCH 5/8] drm/xe/oa: Signal output fences

[Ashutosh Dixit]

Complete 'struct xe_oa_fence' to include the dma_fence used to signal
output fences in the xe_sync array. The fences are signalled
asynchronously. When there are no output fences to signal, the OA
configuration wait is synchronously re-introduced into the ioctl.

Signed-off-by: Ashutosh Dixit <ashutosh.dixit at intel.com>
---
 drivers/gpu/drm/xe/xe_oa.c | 46 +++++++++++++++++++++++++++++++++++---
 1 file changed, 43 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_oa.c b/drivers/gpu/drm/xe/xe_oa.c
index 416e031ac454b..bc421cd0af6ba 100644
--- a/drivers/gpu/drm/xe/xe_oa.c
+++ b/drivers/gpu/drm/xe/xe_oa.c
@@ -96,6 +96,10 @@ struct xe_oa_config_bo {
 };
 
 struct xe_oa_fence {
+	/* @base: dma fence base */
+	struct dma_fence base;
+	/* @lock: lock for the fence */
+	spinlock_t lock;
 	/* @xe: pointer to xe device */
 	struct xe_device *xe;
 	/* @work: work to signal that OA configuration is applied */
@@ -953,9 +957,26 @@ static void xe_oa_fence_work_fn(struct work_struct *w)
 	/* Additional empirical delay needed for NOA programming after registers are written */
 	usleep_range(us, 2 * us);
 
-	kfree(ofence);
+	/* Now signal fence to indicate new OA configuration is active */
+	dma_fence_signal(&ofence->base);
+	dma_fence_put(&ofence->base);
 }
 
+static const char *xe_oa_get_driver_name(struct dma_fence *fence)
+{
+	return "xe_oa";
+}
+
+static const char *xe_oa_get_timeline_name(struct dma_fence *fence)
+{
+	return "unbound";
+}
+
+static const struct dma_fence_ops xe_oa_fence_ops = {
+	.get_driver_name = xe_oa_get_driver_name,
+	.get_timeline_name = xe_oa_get_timeline_name,
+};
+
 static struct xe_oa_fence *xe_oa_fence_init(struct xe_device *xe, struct dma_fence *config_fence)
 {
 	struct xe_oa_fence *ofence;
@@ -967,6 +988,8 @@ static struct xe_oa_fence *xe_oa_fence_init(struct xe_device *xe, struct dma_fen
 	ofence->xe = xe;
 	INIT_WORK(&ofence->work, xe_oa_fence_work_fn);
 	ofence->config_fence = config_fence;
+	spin_lock_init(&ofence->lock);
+	dma_fence_init(&ofence->base, &xe_oa_fence_ops, &ofence->lock, 0, 0);
 
 	return ofence;
 }
@@ -975,8 +998,8 @@ static int xe_oa_emit_oa_config(struct xe_oa_stream *stream, struct xe_oa_config
 {
 	struct xe_oa_config_bo *oa_bo;
 	struct xe_oa_fence *ofence;
+	int i, err, num_signal = 0;
 	struct dma_fence *fence;
-	int err;
 
 	/* Emit OA configuration batch */
 	oa_bo = xe_oa_alloc_config_buffer(stream, config);
@@ -989,13 +1012,30 @@ static int xe_oa_emit_oa_config(struct xe_oa_stream *stream, struct xe_oa_config
 	if (err)
 		goto exit;
 
+	/* Initialize and set fence to signal */
 	ofence = xe_oa_fence_init(stream->oa->xe, fence);
 	if (IS_ERR(ofence)) {
 		err = PTR_ERR(ofence);
 		goto put_fence;
 	}
 
-	xe_oa_fence_work_fn(&ofence->work);
+	for (i = 0; i < stream->num_syncs; i++)
+		xe_sync_entry_signal(&stream->syncs[i], &ofence->base);
+
+	/* Schedule work to signal the fence */
+	queue_work(system_unbound_wq, &ofence->work);
+
+	/* If nothing needs to be signaled we wait synchronously */
+	for (i = 0; i < stream->num_syncs; i++)
+		if (stream->syncs[i].flags & DRM_XE_SYNC_FLAG_SIGNAL)
+			num_signal++;
+	if (!num_signal)
+		flush_work(&ofence->work);
+
+	/* Done with syncs */
+	for (i = 0; i < stream->num_syncs; i++)
+		xe_sync_entry_cleanup(&stream->syncs[i]);
+	kfree(stream->syncs);
 
 	return 0;
 put_fence:
-- 
2.41.0