diff --git a/src/gallium/drivers/iris/iris_blit.c b/src/gallium/drivers/iris/iris_blit.c
index 475e2b63c3a..32a5e8e38df 100644
--- a/src/gallium/drivers/iris/iris_blit.c
+++ b/src/gallium/drivers/iris/iris_blit.c
@@ -262,7 +262,8 @@ iris_blorp_surf_for_resource(struct iris_batch *batch,
 static bool
 is_astc(enum isl_format format)
 {
-   return isl_format_get_layout(format)->txc == ISL_TXC_ASTC;
+   return format != ISL_FORMAT_UNSUPPORTED &&
+          isl_format_get_layout(format)->txc == ISL_TXC_ASTC;
 }
 
 static void
@@ -686,8 +687,13 @@ iris_copy_region(struct blorp_context *blorp,
    enum isl_aux_usage dst_aux_usage =
       copy_region_aux_usage(ice, batch, dst_res, dst_fmt, dst_level, true);
 
-   if (iris_batch_references(batch, src_res->bo))
-      tex_cache_flush_hack(batch, src_fmt, src_res->surf.format);
+   if (iris_batch_references(batch, src_res->bo)) {
+      /* blorp_copy_get_formats() is only valid for compressed surfaces. */
+      tex_cache_flush_hack(batch,
+                           src_aux_usage == ISL_AUX_USAGE_NONE ?
+                           ISL_FORMAT_UNSUPPORTED : src_fmt,
+                           src_res->surf.format);
+   }
 
    if (dst->target == PIPE_BUFFER)
       util_range_add(&dst_res->base.b, &dst_res->valid_buffer_range, dstx, dstx + src_box->width);
diff --git a/src/intel/blorp/blorp.h b/src/intel/blorp/blorp.h
index 3c29100d383..0ec501a80d4 100644
--- a/src/intel/blorp/blorp.h
+++ b/src/intel/blorp/blorp.h
@@ -255,10 +255,16 @@ blorp_blit(struct blorp_batch *batch,
            enum blorp_filter filter,
            bool mirror_x, bool mirror_y);
 
+/* Returns the format the blorp_copy() call can be assumed to use if it
+ * receives a blorp surface which enables lossless compression.
+ */
 enum isl_format
 blorp_copy_get_color_format(const struct isl_device *isl_dev,
                             enum isl_format surf_format);
 
+/* Returns the format the blorp_copy() call can be assumed to use if it
+ * receives a blorp surface which enables lossless compression.
+ */
 void
 blorp_copy_get_formats(const struct isl_device *isl_dev,
                        const struct isl_surf *src_surf,
diff --git a/src/intel/blorp/blorp_blit.c b/src/intel/blorp/blorp_blit.c
index db8a607a926..0c353509692 100644
--- a/src/intel/blorp/blorp_blit.c
+++ b/src/intel/blorp/blorp_blit.c
@@ -3007,6 +3007,10 @@ blorp_copy(struct blorp_batch *batch,
           params.src.aux_usage == ISL_AUX_USAGE_FCV_CCS_E ||
           params.src.aux_usage == ISL_AUX_USAGE_STC_CCS);
 
+   /* The public interface states that the value returned by the format query
+    * is valid for losslessly compressed surfaces. Internally, we're free to
+    * use it as a starting point for all surfaces.
+    */
    blorp_copy_get_formats(isl_dev, &params.src.surf, &params.dst.surf,
                           &params.src.view.format, &params.dst.view.format);