diff --git a/drivers/rwbuffer.c b/drivers/rwbuffer.c
index 6bb6c27625..7cd72246a4 100644
--- a/drivers/rwbuffer.c
+++ b/drivers/rwbuffer.c
@@ -834,9 +834,13 @@ int rwb_read(FAR struct rwbuffer_s *rwb, off_t startblock, uint32_t nblocks,
     }
   else
 #else
-  {
-    ret = rwb->rhreload(rwb->dev, startblock, nblocks, rdbuffer);
-  }
+    {
+      /* No read-ahead buffering, (re)load the data directly into
+       * the user buffer.
+       */
+
+      ret = rwb->rhreload(rwb->dev, startblock, nblocks, rdbuffer);
+    }
 #endif
 
   return ret;
diff --git a/include/nuttx/nx/nxglib.h b/include/nuttx/nx/nxglib.h
index 3b6037c4a9..6e2d1a53d5 100644
--- a/include/nuttx/nx/nxglib.h
+++ b/include/nuttx/nx/nxglib.h
@@ -633,8 +633,12 @@ void nxgl_trapcopy(FAR struct nxgl_trapezoid_s *dest,
  *
  ****************************************************************************/
 
+#if CONFIG_NX_NPLANES == 1
+#  define nxgl_colorcopy(d,s) do { (d)[0] = s[0]; } while (0)
+#else
 void nxgl_colorcopy(nxgl_mxpixel_t dest[CONFIG_NX_NPLANES],
                     const nxgl_mxpixel_t src[CONFIG_NX_NPLANES]);
+#endif
 
 /****************************************************************************
  * Name: nxgl_colorcmp
@@ -646,8 +650,12 @@ void nxgl_colorcopy(nxgl_mxpixel_t dest[CONFIG_NX_NPLANES],
  *
  ****************************************************************************/
 
+#if CONFIG_NX_NPLANES == 1
+#  define nxgl_colorcmp(d,s) ((d)[0] == s[0])
+#else
 bool nxgl_colorcmp(const nxgl_mxpixel_t color1[CONFIG_NX_NPLANES],
                    const nxgl_mxpixel_t color2[CONFIG_NX_NPLANES]);
+#endif
 
 /****************************************************************************
  * Name: nxgl_splitline
diff --git a/libnx/nxglib/Make.defs b/libnx/nxglib/Make.defs
index bc0ca0c934..8593c91aca 100644
--- a/libnx/nxglib/Make.defs
+++ b/libnx/nxglib/Make.defs
@@ -37,14 +37,18 @@
 
 ifeq ($(CONFIG_NX),y)
 
-CSRCS += nxglib_circlepts.c nxglib_circletraps.c nxglib_colorcmp.c
-CSRCS += nxglib_colorcopy.c nxglib_intersecting.c nxglib_nonintersecting.c
-CSRCS += nxglib_nullrect.c nxglib_rectadd.c nxglib_rectcopy.c
-CSRCS += nxglib_rectinside.c nxglib_rectintersect.c nxglib_rectoffset.c
-CSRCS += nxglib_rectoverlap.c nxglib_rectsize.c nxglib_rectunion.c
-CSRCS += nxglib_rgb2yuv.c nxglib_runcopy.c nxglib_runoffset.c
-CSRCS += nxglib_splitline.c nxglib_trapcopy.c nxglib_trapoffset.c
-CSRCS += nxglib_vectoradd.c nxglib_vectsubtract.c nxglib_yuv2rgb.c
+CSRCS += nxglib_circlepts.c nxglib_circletraps.c nxglib_intersecting.c
+CSRCS += nxglib_nonintersecting.c nxglib_nullrect.c nxglib_rectadd.c
+CSRCS += nxglib_rectcopy.c nxglib_rectinside.c nxglib_rectintersect.c
+CSRCS += nxglib_rectoffset.c nxglib_rectoverlap.c nxglib_rectsize.c
+CSRCS += nxglib_rectunion.c nxglib_rgb2yuv.c nxglib_runcopy.c
+CSRCS += nxglib_runoffset.c nxglib_splitline.c nxglib_trapcopy.c
+CSRCS += nxglib_trapoffset.c nxglib_vectoradd.c nxglib_vectsubtract.c
+CSRCS += nxglib_yuv2rgb.c
+
+ifneq ($(CONFIG_NX_NPLANES),1)
+CSRCS += nxglib_colorcmp.c nxglib_colorcopy.c
+endif
 
 # Add the nxglib/ directory to the build