[Mesa-dev] [PATCH v3] st/va: ensure linear memory for dmabuf

[Julien Isorce]

In order to do zero-copy between two different devices
the memory should not be tiled.

Tested with GStreamer on a laptop that has 2 GPUs:
1- gstvaapidecode:
   HW decoding and dmabuf export with nouveau driver on Nvidia GPU.
2- glimagesink:
   EGLImage imports dmabuf on Intel GPU.

TEST: DRI_PRIME=1 gst-launch vaapidecodebin ! glimagesink

Signed-off-by: Julien Isorce <j.isorce at samsung.com>
---
 src/gallium/auxiliary/vl/vl_video_buffer.c | 3 +++
 src/gallium/include/pipe/p_video_codec.h   | 1 +
 src/gallium/state_trackers/va/surface.c    | 8 ++++++++
 3 files changed, 12 insertions(+)

diff --git a/src/gallium/auxiliary/vl/vl_video_buffer.c b/src/gallium/auxiliary/vl/vl_video_buffer.c
index 4a68ac1..b383ad2 100644
--- a/src/gallium/auxiliary/vl/vl_video_buffer.c
+++ b/src/gallium/auxiliary/vl/vl_video_buffer.c
@@ -253,6 +253,9 @@ vl_video_buffer_template(struct pipe_resource *templ,
    templ->bind = PIPE_BIND_SAMPLER_VIEW | PIPE_BIND_RENDER_TARGET;
    templ->usage = usage;
 
+   if (tmpl->bind)
+      templ->bind |= tmpl->bind;
+
    vl_video_buffer_adjust_size(&templ->width0, &templ->height0, plane,
                                tmpl->chroma_format, false);
 }
diff --git a/src/gallium/include/pipe/p_video_codec.h b/src/gallium/include/pipe/p_video_codec.h
index b5575ab..b4b2b9c 100644
--- a/src/gallium/include/pipe/p_video_codec.h
+++ b/src/gallium/include/pipe/p_video_codec.h
@@ -126,6 +126,7 @@ struct pipe_video_buffer
    unsigned width;
    unsigned height;
    bool interlaced;
+   unsigned bind;
 
    /**
     * destroy this video buffer
diff --git a/src/gallium/state_trackers/va/surface.c b/src/gallium/state_trackers/va/surface.c
index 8a6a397..5efb893 100644
--- a/src/gallium/state_trackers/va/surface.c
+++ b/src/gallium/state_trackers/va/surface.c
@@ -621,6 +621,14 @@ vlVaCreateSurfaces2(VADriverContextP ctx, unsigned int format,
 
       switch (memory_type) {
       case VA_SURFACE_ATTRIB_MEM_TYPE_VA:
+         /* The application will clear the TILING flag when the surface is
+          * intended to be exported as dmabuf. Adding shared flag because not
+          * null memory_attibute means VASurfaceAttribExternalBuffers is used.
+          */
+         if (memory_attibute &&
+             !(memory_attibute->flags & VA_SURFACE_EXTBUF_DESC_ENABLE_TILING))
+            templat.bind = PIPE_BIND_LINEAR | PIPE_BIND_SHARED;
+
          surf->buffer = drv->pipe->create_video_buffer(drv->pipe, &templat);
          if (!surf->buffer) {
             FREE(surf);
-- 
1.9.1