+static EGLBoolean
+droid_load_driver(_EGLDisplay *disp, bool swrast)
+{
+ struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
+
+ dri2_dpy->driver_name = loader_get_driver_for_fd(dri2_dpy->fd);
+ if (dri2_dpy->driver_name == NULL)
+ return false;
+
+#ifdef HAVE_DRM_GRALLOC
+ /* Handle control nodes using __DRI_DRI2_LOADER extension and GEM names
+ * for backwards compatibility with drm_gralloc. (Do not use on new
+ * systems.) */
+ dri2_dpy->loader_extensions = droid_dri2_loader_extensions;
+ if (!dri2_load_driver(disp)) {
+ goto error;
+ }
+#else
+ if (swrast) {
+ /* Use kms swrast only with vgem / virtio_gpu.
+ * virtio-gpu fallbacks to software rendering when 3D features
+ * are unavailable since 6c5ab.
+ */
+ if (strcmp(dri2_dpy->driver_name, "vgem") == 0 ||
+ strcmp(dri2_dpy->driver_name, "virtio_gpu") == 0) {
+ free(dri2_dpy->driver_name);
+ dri2_dpy->driver_name = strdup("kms_swrast");
+ } else {
+ goto error;
+ }
+ }
+
+ dri2_dpy->loader_extensions = droid_image_loader_extensions;
+ if (!dri2_load_driver_dri3(disp)) {
+ goto error;
+ }
+#endif
+
+ return true;
+
+error:
+ free(dri2_dpy->driver_name);
+ dri2_dpy->driver_name = NULL;
+ return false;
+}
+
+static void
+droid_unload_driver(_EGLDisplay *disp)
+{
+ struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
+
+ dlclose(dri2_dpy->driver);
+ dri2_dpy->driver = NULL;
+ free(dri2_dpy->driver_name);
+ dri2_dpy->driver_name = NULL;
+}
+
+static int
+droid_filter_device(_EGLDisplay *disp, int fd, const char *vendor)
+{
+ drmVersionPtr ver = drmGetVersion(fd);
+ if (!ver)
+ return -1;
+
+ if (strcmp(vendor, ver->name) != 0) {
+ drmFreeVersion(ver);
+ return -1;
+ }
+
+ drmFreeVersion(ver);
+ return 0;
+}
+
+static EGLBoolean
+droid_probe_device(_EGLDisplay *disp, bool swrast)
+{
+ /* Check that the device is supported, by attempting to:
+ * - load the dri module
+ * - and, create a screen
+ */
+ if (!droid_load_driver(disp, swrast))
+ return EGL_FALSE;
+
+ if (!dri2_create_screen(disp)) {
+ _eglLog(_EGL_WARNING, "DRI2: failed to create screen");
+ droid_unload_driver(disp);
+ return EGL_FALSE;
+ }
+ return EGL_TRUE;
+}
+
+#ifdef HAVE_DRM_GRALLOC
+static EGLBoolean
+droid_open_device(_EGLDisplay *disp, bool swrast)
+{
+ struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
+ int fd = -1, err = -EINVAL;
+
+ if (swrast)
+ return EGL_FALSE;
+
+ if (dri2_dpy->gralloc->perform)
+ err = dri2_dpy->gralloc->perform(dri2_dpy->gralloc,
+ GRALLOC_MODULE_PERFORM_GET_DRM_FD,
+ &fd);
+ if (err || fd < 0) {
+ _eglLog(_EGL_WARNING, "fail to get drm fd");
+ return EGL_FALSE;
+ }
+
+ dri2_dpy->fd = os_dupfd_cloexec(fd);
+ if (dri2_dpy->fd < 0)
+ return EGL_FALSE;
+
+ if (drmGetNodeTypeFromFd(dri2_dpy->fd) == DRM_NODE_RENDER)
+ return EGL_FALSE;
+
+ return droid_probe_device(disp, swrast);
+}
+#else
+static EGLBoolean
+droid_open_device(_EGLDisplay *disp, bool swrast)
+{
+#define MAX_DRM_DEVICES 64
+ struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
+ drmDevicePtr device, devices[MAX_DRM_DEVICES] = { NULL };
+ int num_devices;
+
+ char *vendor_name = NULL;
+ char vendor_buf[PROPERTY_VALUE_MAX];
+
+#ifdef EGL_FORCE_RENDERNODE
+ const unsigned node_type = DRM_NODE_RENDER;
+#else
+ const unsigned node_type = swrast ? DRM_NODE_PRIMARY : DRM_NODE_RENDER;
+#endif
+
+ if (property_get("drm.gpu.vendor_name", vendor_buf, NULL) > 0)
+ vendor_name = vendor_buf;
+
+ num_devices = drmGetDevices2(0, devices, ARRAY_SIZE(devices));
+ if (num_devices < 0)
+ return EGL_FALSE;
+
+ for (int i = 0; i < num_devices; i++) {
+ device = devices[i];
+
+ if (!(device->available_nodes & (1 << node_type)))
+ continue;
+
+ dri2_dpy->fd = loader_open_device(device->nodes[node_type]);
+ if (dri2_dpy->fd < 0) {
+ _eglLog(_EGL_WARNING, "%s() Failed to open DRM device %s",
+ __func__, device->nodes[node_type]);
+ continue;
+ }
+
+ /* If a vendor is explicitly provided, we use only that.
+ * Otherwise we fall-back the first device that is supported.
+ */
+ if (vendor_name) {
+ if (droid_filter_device(disp, dri2_dpy->fd, vendor_name)) {
+ /* Device does not match - try next device */
+ close(dri2_dpy->fd);
+ dri2_dpy->fd = -1;
+ continue;
+ }
+ /* If the requested device matches - use it. Regardless if
+ * init fails, do not fall-back to any other device.
+ */
+ if (!droid_probe_device(disp, false)) {
+ close(dri2_dpy->fd);
+ dri2_dpy->fd = -1;
+ }
+
+ break;
+ }
+ if (droid_probe_device(disp, swrast))
+ break;
+
+ /* No explicit request - attempt the next device */
+ close(dri2_dpy->fd);
+ dri2_dpy->fd = -1;
+ }
+ drmFreeDevices(devices, num_devices);
+
+ if (dri2_dpy->fd < 0) {
+ _eglLog(_EGL_WARNING, "Failed to open %s DRM device",
+ vendor_name ? "desired": "any");
+ return EGL_FALSE;
+ }
+
+ return EGL_TRUE;
+#undef MAX_DRM_DEVICES
+}
+
+#endif
+