freedreno/drm: handle ancient kernels

Older kernels did not support `MSM_INFO_GET_IOVA`.  But this is only
required for (a) clover (ie. `fd_set_global_binding()`) and drm paths
that are limited to newer kernels.  So move the location of the assert
to fix new userspace on old kernels.

Fixes: c9e8df61dc ("freedreno: Initialize the bo's iova at creation time.")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Tested-by: Ilia Mirkin <imirkin@alum.mit.edu>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5081>

src/freedreno/drm/freedreno_bo.c

@@ -236,6 +236,8 @@ fd_bo_mark_for_dump(struct fd_bo *bo)
 
 uint64_t fd_bo_get_iova(struct fd_bo *bo)
 {
+	/* ancient kernels did not support this */
+	assert(bo->iova != 0);
 	return bo->iova;
 }
 

src/freedreno/drm/msm_bo.c

@@ -112,7 +112,8 @@ static uint64_t msm_bo_iova(struct fd_bo *bo)
 	int ret;
 
 	ret = drmCommandWriteRead(bo->dev->fd, DRM_MSM_GEM_INFO, &req, sizeof(req));
-	debug_assert(ret == 0);
+	if (ret)
+		return 0;
 
 	return req.value;
 }