diff --git a/hw/display/sm501.c b/hw/display/sm501.c
index 8966b69bc7..aba447c18b 100644
--- a/hw/display/sm501.c
+++ b/hw/display/sm501.c
@@ -1558,89 +1558,9 @@ typedef void draw_hwc_line_func(uint8_t *d, const uint8_t *s,
                                 int width, const uint8_t *palette,
                                 int c_x, int c_y);
 
-#define DEPTH 8
-#include "sm501_template.h"
-
-#define DEPTH 15
-#include "sm501_template.h"
-
-#define BGR_FORMAT
-#define DEPTH 15
-#include "sm501_template.h"
-
-#define DEPTH 16
-#include "sm501_template.h"
-
-#define BGR_FORMAT
-#define DEPTH 16
-#include "sm501_template.h"
-
 #define DEPTH 32
 #include "sm501_template.h"
 
-#define BGR_FORMAT
-#define DEPTH 32
-#include "sm501_template.h"
-
-static draw_line_func *draw_line8_funcs[] = {
-    draw_line8_8,
-    draw_line8_15,
-    draw_line8_16,
-    draw_line8_32,
-    draw_line8_32bgr,
-    draw_line8_15bgr,
-    draw_line8_16bgr,
-};
-
-static draw_line_func *draw_line16_funcs[] = {
-    draw_line16_8,
-    draw_line16_15,
-    draw_line16_16,
-    draw_line16_32,
-    draw_line16_32bgr,
-    draw_line16_15bgr,
-    draw_line16_16bgr,
-};
-
-static draw_line_func *draw_line32_funcs[] = {
-    draw_line32_8,
-    draw_line32_15,
-    draw_line32_16,
-    draw_line32_32,
-    draw_line32_32bgr,
-    draw_line32_15bgr,
-    draw_line32_16bgr,
-};
-
-static draw_hwc_line_func *draw_hwc_line_funcs[] = {
-    draw_hwc_line_8,
-    draw_hwc_line_15,
-    draw_hwc_line_16,
-    draw_hwc_line_32,
-    draw_hwc_line_32bgr,
-    draw_hwc_line_15bgr,
-    draw_hwc_line_16bgr,
-};
-
-static inline int get_depth_index(DisplaySurface *surface)
-{
-    switch (surface_bits_per_pixel(surface)) {
-    default:
-    case 8:
-        return 0;
-    case 15:
-        return 1;
-    case 16:
-        return 2;
-    case 32:
-        if (is_surface_bgr(surface)) {
-            return 4;
-        } else {
-            return 3;
-        }
-    }
-}
-
 static void sm501_update_display(void *opaque)
 {
     SM501State *s = (SM501State *)opaque;
@@ -1652,7 +1572,6 @@ static void sm501_update_display(void *opaque)
     int height = get_height(s, crt);
     int src_bpp = get_bpp(s, crt);
     int dst_bpp = surface_bytes_per_pixel(surface);
-    int dst_depth_index = get_depth_index(surface);
     draw_line_func *draw_line = NULL;
     draw_hwc_line_func *draw_hwc_line = NULL;
     int full_update = 0;
@@ -1662,6 +1581,8 @@ static void sm501_update_display(void *opaque)
     uint8_t hwc_palette[3 * 3];
     uint8_t *hwc_src = NULL;
 
+    assert(dst_bpp == 4); /* Output is always 32-bit RGB */
+
     if (!((crt ? s->dc_crt_control : s->dc_panel_control)
           & SM501_DC_CRT_CONTROL_ENABLE)) {
         return;
@@ -1674,13 +1595,13 @@ static void sm501_update_display(void *opaque)
     /* choose draw_line function */
     switch (src_bpp) {
     case 1:
-        draw_line = draw_line8_funcs[dst_depth_index];
+        draw_line = draw_line8_32;
         break;
     case 2:
-        draw_line = draw_line16_funcs[dst_depth_index];
+        draw_line = draw_line16_32;
         break;
     case 4:
-        draw_line = draw_line32_funcs[dst_depth_index];
+        draw_line = draw_line32_32;
         break;
     default:
         qemu_log_mask(LOG_GUEST_ERROR, "sm501: update display"
@@ -1691,7 +1612,7 @@ static void sm501_update_display(void *opaque)
     /* set up to draw hardware cursor */
     if (is_hwc_enabled(s, crt)) {
         /* choose cursor draw line function */
-        draw_hwc_line = draw_hwc_line_funcs[dst_depth_index];
+        draw_hwc_line = draw_hwc_line_32;
         hwc_src = get_hwc_address(s, crt);
         c_x = get_hwc_x(s, crt);
         c_y = get_hwc_y(s, crt);