+ case GL_LUMINANCE12_ALPHA4:
+ case GL_LUMINANCE12_ALPHA12:
+ case GL_LUMINANCE16_ALPHA16:
+ /* i915 could implement this mode using MT_32BIT_RG1616. However, this
+ * would require an extra swizzle instruction in the fragment shader to
+ * convert the { R, G, 1.0, 1.0 } to { R, R, R, G }.
+ */
+#ifndef I915
+ return MESA_FORMAT_AL1616;
+#else
+ /* FALLTHROUGH */
+#endif
+