[src/trunk]: src/sys/dev/rasops Real fix for 24-bpp color:

[rin <rin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/cb679cc564c7
branches:  trunk
changeset: 964468:cb679cc564c7
user:      rin <rin%NetBSD.org@localhost>
date:      Fri Aug 02 23:24:37 2019 +0000

description:
Real fix for 24-bpp color:
- When centering screen, locate effective base address of framebuffer to
  both word and 24-bit color boundary.
- Consistently convert ri_devcmap to ``big endian'' if not RI_BSWAP.

Also, fix possible bug for 15/16-bpp with RI_BSWAP (not tested).

diffstat:

 sys/dev/rasops/rasops.c   |  95 +++++++++++++++++++++++++++++-----------------
 sys/dev/rasops/rasops24.c |   5 +-
 2 files changed, 61 insertions(+), 39 deletions(-)

diffs (167 lines):

diff -r bc53bef2e579 -r cb679cc564c7 sys/dev/rasops/rasops.c
--- a/sys/dev/rasops/rasops.c   Fri Aug 02 23:05:42 2019 +0000
+++ b/sys/dev/rasops/rasops.c   Fri Aug 02 23:24:37 2019 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: rasops.c,v 1.107 2019/08/02 04:22:04 rin Exp $        */
+/*      $NetBSD: rasops.c,v 1.108 2019/08/02 23:24:37 rin Exp $        */
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rasops.c,v 1.107 2019/08/02 04:22:04 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rasops.c,v 1.108 2019/08/02 23:24:37 rin Exp $");
 
 #include "opt_rasops.h"
 #include "rasops_glue.h"
@@ -412,7 +412,6 @@
        } else
 #endif
        {
-
                ri->ri_cols = ri->ri_emuwidth / ri->ri_font->fontwidth;
                ri->ri_rows = ri->ri_emuheight / ri->ri_font->fontheight;
        }
@@ -434,17 +433,31 @@
 
        /* Now centre our window if needs be */
        if ((ri->ri_flg & RI_CENTER) != 0) {
-               ri->ri_bits += (((ri->ri_width * bpp >> 3) -
-                   ri->ri_emustride) >> 1) & ~3;
-               ri->ri_bits += ((ri->ri_height - ri->ri_emuheight) >> 1) *
+               uint32_t xoff, yoff;
+
+               xoff = ((ri->ri_width * bpp >> 3) - ri->ri_emustride) >> 1;
+               if (ri->ri_depth != 24) {
+                       /*
+                        * Truncate to word boundary.
+                        */
+                       xoff &= ~3;
+               } else {
+                       /*
+                        * Truncate to word and 24-bit color boundary.
+                        */
+                       xoff = (xoff / (4 * 3)) * (4 * 3);
+               }
+
+               yoff = ((ri->ri_height - ri->ri_emuheight) >> 1) *
                    ri->ri_stride;
+
+               ri->ri_bits += xoff;
+               ri->ri_bits += yoff;
                if (ri->ri_hwbits != NULL) {
-                       ri->ri_hwbits += (((ri->ri_width * bpp >> 3) -
-                           ri->ri_emustride) >> 1) & ~3;
-                       ri->ri_hwbits +=
-                           ((ri->ri_height - ri->ri_emuheight) >> 1) *
-                           ri->ri_stride;
+                       ri->ri_hwbits += xoff;
+                       ri->ri_hwbits += yoff;
                }
+
                ri->ri_yorigin = (int)(ri->ri_bits - ri->ri_origbits) /
                    ri->ri_stride;
                ri->ri_xorigin = (((int)(ri->ri_bits - ri->ri_origbits) %
@@ -901,39 +914,49 @@
                        c |= (uint32_t)(*p << (ri->ri_bnum - 8)) << ri->ri_bpos;
                p++;
 
-               /* Fill the word for generic routines, which want this */
-               if (ri->ri_depth == 8) {
+               /*
+                * Swap byte order if necessary. Then, fill the word for
+                * generic routines, which want this.
+                */
+               switch (ri->ri_depth) {
+               case 8:
                        c |= c << 8;
                        c |= c << 16;
-               } else if (ri->ri_depth == 15 || ri->ri_depth == 16)
+                       break;
+               case 15:
+               case 16:
+                       if ((ri->ri_flg & RI_BSWAP) != 0)
+                               c = bswap16(c);
                        c |= c << 16;
-               else if (ri->ri_depth == 24) {
+                       break;
+               case 24:
 #if BYTE_ORDER == LITTLE_ENDIAN
-#  ifndef RASOPS_SMALL
-                       if (ri->ri_font->fontwidth != 12)
-#  endif
-                               c = (c & 0x0000ff) << 16 | (c & 0x00ff00) |
+                       if ((ri->ri_flg & RI_BSWAP) == 0)
+#else
+                       if ((ri->ri_flg & RI_BSWAP) != 0)
+#endif
+                       {
+                               /*
+                                * Convert to ``big endian'' if not RI_BSWAP.
+                                */
+                               c = (c & 0x0000ff) << 16|
+                                   (c & 0x00ff00) |
                                    (c & 0xff0000) >> 16;
-#  ifndef RASOPS_SMALL
-                       else
-                               c = (c & 0x0000ff) | (c & 0x00ff00) << 8 |
-                                   (c & 0xff0000) >> 8;
-#  endif
-#else
-                       /* XXXRO What should we do here? */
-#endif
+                       }
+
+                       /*
+                        * No worries, we use generic routines only for
+                        * gray colors, where all 3 bytes are same.
+                        */
                        c |= (c & 0xff) << 24;
+                       break;
+               case 32:
+                       if ((ri->ri_flg & RI_BSWAP) != 0)
+                               c = bswap32(c);
+                       break;
                }
 
-               /* 24bpp does bswap on the fly. {32,16,15}bpp do it here. */
-               if ((ri->ri_flg & RI_BSWAP) == 0)
-                       ri->ri_devcmap[i] = c;
-               else if (ri->ri_depth == 15 || ri->ri_depth == 16)
-                       ri->ri_devcmap[i] = bswap16(c);
-               else if (ri->ri_depth == 32)
-                       ri->ri_devcmap[i] = bswap32(c);
-               else /* 8, 24 */
-                       ri->ri_devcmap[i] = c;
+               ri->ri_devcmap[i] = c;
        }
 }
 
diff -r bc53bef2e579 -r cb679cc564c7 sys/dev/rasops/rasops24.c
--- a/sys/dev/rasops/rasops24.c Fri Aug 02 23:05:42 2019 +0000
+++ b/sys/dev/rasops/rasops24.c Fri Aug 02 23:24:37 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rasops24.c,v 1.45 2019/08/02 23:05:42 rin Exp $        */
+/*     $NetBSD: rasops24.c,v 1.46 2019/08/02 23:24:37 rin Exp $        */
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rasops24.c,v 1.45 2019/08/02 23:05:42 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rasops24.c,v 1.46 2019/08/02 23:24:37 rin Exp $");
 
 #include "opt_rasops.h"
 
@@ -329,7 +329,6 @@
        }
 
        /* Trailing slop */
-       /* XXX handle with masks, bring under control of RI_BSWAP */
        dbp = (uint8_t *)dp;
        for (cnt = num & 3; cnt; cnt--) {
                *dbp++ = (clr >> 16);