etnaviv: drm: Be able to mark end of context init

Add etna_cmd_stream_mark_end_of_context_init(..) which stores the current
offset of the cmd stream as offset_end_of_context_init. This information
will be used to downgrade a cmd stream flush to a noop.

Signed-off-by: Christian Gmeiner <cgmeiner@igalia.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25849>

diff --git a/src/etnaviv/drm/etnaviv_cmd_stream.c b/src/etnaviv/drm/etnaviv_cmd_stream.c
index 657ef0c..89e28e2 100644 (file)
--- a/src/etnaviv/drm/etnaviv_cmd_stream.c
+++ b/src/etnaviv/drm/etnaviv_cmd_stream.c
@@ -230,6 +230,9 @@ void etna_cmd_stream_flush(struct etna_cmd_stream *stream, int in_fence_fd,
        if (gpu->dev->use_softpin)
                req.flags |= ETNA_SUBMIT_SOFTPIN;
 
+       if (stream->offset == priv->offset_end_of_context_init && !out_fence_fd)
+               is_noop = true;
+
        if (unlikely(is_noop))
                ret = 0;
        else
@@ -254,6 +257,7 @@ void etna_cmd_stream_flush(struct etna_cmd_stream *stream, int in_fence_fd,
        priv->submit.nr_relocs = 0;
        priv->submit.nr_pmrs = 0;
        priv->nr_bos = 0;
+       priv->offset_end_of_context_init = 0;
 }
 
 void etna_cmd_stream_reloc(struct etna_cmd_stream *stream,
@@ -284,6 +288,18 @@ void etna_cmd_stream_ref_bo(struct etna_cmd_stream *stream, struct etna_bo *bo,
        bo2idx(stream, bo, flags);
 }
 
+void etna_cmd_stream_mark_end_of_context_init(struct etna_cmd_stream *stream)
+{
+   struct etna_cmd_stream_priv *priv = etna_cmd_stream_priv(stream);
+
+   /* 
+    * All commands before the end of context init are guaranteed to only alter GPU internal
+    * state and have no externally visible side effects, so we can skip the submit if the
+    * command buffer contains only context init commands.
+    */
+   priv->offset_end_of_context_init = stream->offset;
+}
+
 void etna_cmd_stream_perf(struct etna_cmd_stream *stream, const struct etna_perf *p)
 {
        struct etna_cmd_stream_priv *priv = etna_cmd_stream_priv(stream);

diff --git a/src/etnaviv/drm/etnaviv_drmif.h b/src/etnaviv/drm/etnaviv_drmif.h
index 9b49245..ad77039 100644 (file)
--- a/src/etnaviv/drm/etnaviv_drmif.h
+++ b/src/etnaviv/drm/etnaviv_drmif.h
@@ -206,6 +206,8 @@ void etna_cmd_stream_reloc(struct etna_cmd_stream *stream, const struct etna_rel
 void etna_cmd_stream_ref_bo(struct etna_cmd_stream *stream,
                struct etna_bo *bo, uint32_t flags);
 
+void etna_cmd_stream_mark_end_of_context_init(struct etna_cmd_stream *stream);
+
 /* performance monitoring functions:
  */
 

diff --git a/src/etnaviv/drm/etnaviv_priv.h b/src/etnaviv/drm/etnaviv_priv.h
index 0f34c63..630f91c 100644 (file)
--- a/src/etnaviv/drm/etnaviv_priv.h
+++ b/src/etnaviv/drm/etnaviv_priv.h
@@ -134,6 +134,7 @@ struct etna_cmd_stream_priv {
        struct etna_pipe *pipe;
 
        uint32_t last_timestamp;
+       uint32_t offset_end_of_context_init;
 
        /* submit ioctl related tables: */
        struct {