diff --git a/src/freedreno/registers/a6xx.xml b/src/freedreno/registers/a6xx.xml
index 3f482edca4a..fe5b6adc37b 100644
--- a/src/freedreno/registers/a6xx.xml
+++ b/src/freedreno/registers/a6xx.xml
@@ -3294,7 +3294,12 @@ to upconvert to 32b float internally?
 		 -->
 		<bitfield name="ARRAY_PITCH" low="0" high="13" shr="12" type="uint"/>
 		<bitfield name="MIN_LAYERSZ" low="23" high="26" shr="12"/>
-		<bitfield name="UNK27" pos="27" type="boolean"/>
+		<!--
+		by default levels with w < 16 are linear
+		TILE_ALL makes all levels have tiling
+		seems required when using UBWC, since all levels have UBWC (can possibly be disabled?)
+		 -->
+		<bitfield name="TILE_ALL" pos="27" type="boolean"/>
 		<bitfield name="FLAG" pos="28" type="boolean"/>
 	</reg32>
 	<reg32 offset="4" name="4">
@@ -3315,11 +3320,10 @@ to upconvert to 32b float internally?
 		<bitfield name="FLAG_BUFFER_ARRAY_PITCH" low="0" high="16" shr="4" type="uint"/>
 	</reg32>
 	<reg32 offset="10" name="10">
-		<!--
-		I see some other bits set by blob above FLAG_BUFFER_PITCH, but they
-		don't seem to be particularly sensible... or needed for UBWC to work
-		 -->
 		<bitfield name="FLAG_BUFFER_PITCH" low="0" high="6" shr="6" type="uint"/>
+		<!-- log2 size of the first level, required for mipmapping -->
+		<bitfield name="FLAG_BUFFER_LOGW" low="8" high="11" type="uint"/>
+		<bitfield name="FLAG_BUFFER_LOGH" low="12" high="15" type="uint"/>
 	</reg32>
 	<reg32 offset="11" name="11"/>
 	<reg32 offset="12" name="12"/>
diff --git a/src/gallium/drivers/freedreno/a6xx/fd6_image.c b/src/gallium/drivers/freedreno/a6xx/fd6_image.c
index 3b476440856..b6d38379945 100644
--- a/src/gallium/drivers/freedreno/a6xx/fd6_image.c
+++ b/src/gallium/drivers/freedreno/a6xx/fd6_image.c
@@ -183,7 +183,7 @@ static void emit_image_tex(struct fd_ringbuffer *ring, struct fd6_image *img)
 		A6XX_TEX_CONST_2_TYPE(img->type) |
 		A6XX_TEX_CONST_2_PITCH(img->pitch));
 	OUT_RING(ring, A6XX_TEX_CONST_3_ARRAY_PITCH(img->array_pitch) |
-		COND(ubwc_enabled, A6XX_TEX_CONST_3_FLAG | A6XX_TEX_CONST_3_UNK27));
+		COND(ubwc_enabled, A6XX_TEX_CONST_3_FLAG | A6XX_TEX_CONST_3_TILE_ALL));
 	if (img->bo) {
 		OUT_RELOC(ring, img->bo, img->offset,
 				(uint64_t)A6XX_TEX_CONST_5_DEPTH(img->depth) << 32, 0);
diff --git a/src/gallium/drivers/freedreno/a6xx/fd6_texture.c b/src/gallium/drivers/freedreno/a6xx/fd6_texture.c
index 5df197c62c9..6ef7b16ab87 100644
--- a/src/gallium/drivers/freedreno/a6xx/fd6_texture.c
+++ b/src/gallium/drivers/freedreno/a6xx/fd6_texture.c
@@ -318,7 +318,7 @@ fd6_sampler_view_create(struct pipe_context *pctx, struct pipe_resource *prsc,
 	}
 
 	if (so->ubwc_enabled) {
-		so->texconst3 |= A6XX_TEX_CONST_3_FLAG | A6XX_TEX_CONST_3_UNK27;
+		so->texconst3 |= A6XX_TEX_CONST_3_FLAG | A6XX_TEX_CONST_3_TILE_ALL;
 	}
 
 	return &so->base;