Use ivshmem-backed virtio-GPU as KMS driver in the case of QNX

The QNX scenario uses ivshmem-backed virtio-GPU for display, a special
use case for us. We distinguish this scenario by checking whether the
ivshmem virtio-GPU is the only virtio-GPU on the system.

Tracked-On: OAM-127906
Signed-off-by: Weifeng Liu <weifeng.liu@intel.com>

Author: phreer

cros_gralloc/cros_gralloc_driver.cc

@@ -958,9 +958,17 @@ int cros_gralloc_driver::select_render_driver(uint64_t gpu_grp_type)
 
 int cros_gralloc_driver::select_kms_driver(uint64_t gpu_grp_type)
 {
+	// virtio-GPU without blob cannot import external buffers.
 	if (gpu_grp_type & GPU_GRP_TYPE_HAS_VIRTIO_GPU_NO_BLOB_BIT) {
 		return GPU_GRP_TYPE_VIRTIO_GPU_NO_BLOB_IDX;
 	}
+	// QNX case: virtio-GPU is ivshmem backed device and cannot import external buffers.
+	// Screen cast also uses ivshmem virtio-GPU but we have virtio-GPU supporting blob.
+	if ((gpu_grp_type & GPU_GRP_TYPE_HAS_VIRTIO_GPU_IVSHMEM_BIT) &&
+	    !(gpu_grp_type & GPU_GRP_TYPE_HAS_VIRTIO_GPU_BLOB_BIT) &&
+	    !(gpu_grp_type & GPU_GRP_TYPE_HAS_VIRTIO_GPU_BLOB_P2P_BIT)) {
+		return GPU_GRP_TYPE_VIRTIO_GPU_IVSHMEM_IDX;
+	}
 	if (gpu_grp_type & GPU_GRP_TYPE_HAS_INTEL_DGPU_BIT) {
 		return GPU_GRP_TYPE_INTEL_DGPU_IDX;
 	}