virtgpu: enable blobs for decoder output buffers

Enabling this requires two changes. First, the check that prevents
BO_USE_RENDERING/BO_USE_TEXTURE buffers from being blobs is removed,
since decoder output buffers are generally used as textures. Second,
NV12 format with no SW usage is added to the list of configurations that
use blobs.

This change also removes the assumption that blobs are mappable, instead
keying off of the software usage flags.

BUG=b:169212117
TEST=Play YouTube on ARCVM

Change-Id: I3fbe744a1ad406fc27f9912296ae4f9b1b55f903
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/2430540
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Commit-Queue: David Stevens <stevensd@chromium.org>
Tested-by: David Stevens <stevensd@chromium.org>

diff --git a/virtio_gpu.c b/virtio_gpu.c
index 69c75ca..009f810 100644 (file)
--- a/virtio_gpu.c
+++ b/virtio_gpu.c
@@ -683,10 +683,11 @@ static int virtio_gpu_bo_create_blob(struct driver *drv, struct bo *bo)
        uint32_t cmd[VIRGL_PIPE_RES_CREATE_SIZE + 1] = { 0 };
        struct drm_virtgpu_resource_create_blob drm_rc_blob = { 0 };
 
-       uint32_t blob_flags = VIRTGPU_BLOB_FLAG_USE_MAPPABLE | VIRTGPU_BLOB_FLAG_USE_SHAREABLE;
-       if (bo->meta.use_flags & BO_USE_NON_GPU_HW) {
+       uint32_t blob_flags = VIRTGPU_BLOB_FLAG_USE_SHAREABLE;
+       if (bo->meta.use_flags & BO_USE_SW_MASK)
+               blob_flags |= VIRTGPU_BLOB_FLAG_USE_MAPPABLE;
+       if (bo->meta.use_flags & BO_USE_NON_GPU_HW)
                blob_flags |= VIRTGPU_BLOB_FLAG_USE_CROSS_DEVICE;
-       }
 
        stride = drv_stride_from_format(bo->meta.format, bo->meta.width, 0);
        drv_bo_from_format(bo, stride, bo->meta.height, bo->meta.format);
@@ -732,19 +733,23 @@ static bool should_use_blob(struct driver *drv, uint32_t format, uint64_t use_fl
        if (!priv->host_gbm_enabled)
                return false;
 
-       // Focus on non-GPU apps for now
-       if (use_flags & (BO_USE_RENDERING | BO_USE_TEXTURE))
-               return false;
-
-       // Simple, strictly defined formats for now
-       if (format != DRM_FORMAT_YVU420_ANDROID && format != DRM_FORMAT_R8)
+       // Use regular resources if only the GPU needs efficient access
+       if (!(use_flags &
+             (BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN | BO_USE_LINEAR | BO_USE_NON_GPU_HW)))
                return false;
 
-       if (use_flags &
-           (BO_USE_SW_READ_OFTEN | BO_USE_SW_WRITE_OFTEN | BO_USE_LINEAR | BO_USE_NON_GPU_HW))
+       switch (format) {
+       case DRM_FORMAT_YVU420_ANDROID:
+       case DRM_FORMAT_R8:
+               // Formats with strictly defined strides are supported
                return true;
-
-       return false;
+       case DRM_FORMAT_NV12:
+               // Knowing buffer metadata at buffer creation isn't yet supported, so buffers
+               // can't be properly mapped into the guest.
+               return (use_flags & BO_USE_SW_MASK) == 0;
+       default:
+               return false;
+       }
 }
 
 static int virtio_gpu_bo_create(struct bo *bo, uint32_t width, uint32_t height, uint32_t format,