From 7713fff47d31e7607e52c9247fb7b628ed6bb096 Mon Sep 17 00:00:00 2001
From: Peter Maydell <peter.maydell@linaro.org>
Date: Mon, 15 Feb 2021 10:21:49 +0000
Subject: [PATCH] hw/display/tcx: Drop unnecessary code for handling BGR format
 outputs

For a long time now the UI layer has guaranteed that the console
surface is always 32 bits per pixel, RGB. The TCX code already
assumes 32bpp, but it still has some checks of is_surface_bgr()
in an attempt to support 32bpp BGR. is_surface_bgr() will always
return false for the qemu_console_surface(), unless the display
device itself has deliberately created an alternate-format
surface via a function like qemu_create_displaysurface_from().

Drop the never-used BGR-handling code, and assert that we have
a 32-bit surface rather than just doing nothing if it isn't.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210215102149.20513-1-peter.maydell@linaro.org
---
 hw/display/tcx.c | 31 ++++++++-----------------------
 1 file changed, 8 insertions(+), 23 deletions(-)

diff --git a/hw/display/tcx.c b/hw/display/tcx.c
index 965f92ff6b..d3db304657 100644
--- a/hw/display/tcx.c
+++ b/hw/display/tcx.c
@@ -128,15 +128,10 @@ static int tcx_check_dirty(TCXState *s, DirtyBitmapSnapshot *snap,
 
 static void update_palette_entries(TCXState *s, int start, int end)
 {
-    DisplaySurface *surface = qemu_console_surface(s->con);
     int i;
 
     for (i = start; i < end; i++) {
-        if (is_surface_bgr(surface)) {
-            s->palette[i] = rgb_to_pixel32bgr(s->r[i], s->g[i], s->b[i]);
-        } else {
-            s->palette[i] = rgb_to_pixel32(s->r[i], s->g[i], s->b[i]);
-        }
+        s->palette[i] = rgb_to_pixel32(s->r[i], s->g[i], s->b[i]);
     }
     tcx_set_dirty(s, 0, memory_region_size(&s->vram_mem));
 }
@@ -181,21 +176,18 @@ static void tcx_draw_cursor32(TCXState *s1, uint8_t *d,
 }
 
 /*
-  XXX Could be much more optimal:
-  * detect if line/page/whole screen is in 24 bit mode
-  * if destination is also BGR, use memcpy
-  */
+ * XXX Could be much more optimal:
+ * detect if line/page/whole screen is in 24 bit mode
+ */
 static inline void tcx24_draw_line32(TCXState *s1, uint8_t *d,
                                      const uint8_t *s, int width,
                                      const uint32_t *cplane,
                                      const uint32_t *s24)
 {
-    DisplaySurface *surface = qemu_console_surface(s1->con);
-    int x, bgr, r, g, b;
+    int x, r, g, b;
     uint8_t val, *p8;
     uint32_t *p = (uint32_t *)d;
     uint32_t dval;
-    bgr = is_surface_bgr(surface);
     for(x = 0; x < width; x++, s++, s24++) {
         if (be32_to_cpu(*cplane) & 0x03000000) {
             /* 24-bit direct, BGR order */
@@ -204,10 +196,7 @@ static inline void tcx24_draw_line32(TCXState *s1, uint8_t *d,
             b = *p8++;
             g = *p8++;
             r = *p8;
-            if (bgr)
-                dval = rgb_to_pixel32bgr(r, g, b);
-            else
-                dval = rgb_to_pixel32(r, g, b);
+            dval = rgb_to_pixel32(r, g, b);
         } else {
             /* 8-bit pseudocolor */
             val = *s;
@@ -230,9 +219,7 @@ static void tcx_update_display(void *opaque)
     int y, y_start, dd, ds;
     uint8_t *d, *s;
 
-    if (surface_bits_per_pixel(surface) != 32) {
-        return;
-    }
+    assert(surface_bits_per_pixel(surface) == 32);
 
     page = 0;
     y_start = -1;
@@ -283,9 +270,7 @@ static void tcx24_update_display(void *opaque)
     uint8_t *d, *s;
     uint32_t *cptr, *s24;
 
-    if (surface_bits_per_pixel(surface) != 32) {
-            return;
-    }
+    assert(surface_bits_per_pixel(surface) == 32);
 
     page = 0;
     y_start = -1;