git.openwrt.org Git - openwrt/staging/pepe2k.git/blob

   1 From ca621585c573cae54dc1235d90822e8bcef2f73d Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.com>
   3 Date: Wed, 11 Sep 2024 15:23:33 +0100
   4 Subject: [PATCH] drm/vc4: Use the TPZ scaling filter for 1x1 source images
   5
   6 The documentation says that the TPZ filter can not upscale,
   7 and requesting a scaling factor > 1:1 will output the original
   8 image in the top left, and repeat the right/bottom most pixels
   9 thereafter.
  10 That fits perfectly with upscaling a 1x1 image which is done
  11 a fair amount by some compositors to give solid colour, and it
  12 saves a large amount of LBM (TPZ is based on src size, whilst
  13 PPF is based on dest size).
  14
  15 Select TPZ filter for images with source rectangle <=1.
  16
  17 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
  18 ---
  19  drivers/gpu/drm/vc4/vc4_plane.c | 21 +++++++++++++++------
  20  1 file changed, 15 insertions(+), 6 deletions(-)
  21
  22 --- a/drivers/gpu/drm/vc4/vc4_plane.c
  23 +++ b/drivers/gpu/drm/vc4/vc4_plane.c
  24 @@ -265,7 +265,11 @@ static enum vc4_scaling_mode vc4_get_sca
  25  {
  26         if (dst == src >> 16)
  27                 return VC4_SCALING_NONE;
  28 -       if (3 * dst >= 2 * (src >> 16))
  29 +
  30 +       if (src <= (1 << 16))
  31 +               /* Source rectangle <= 1 pixel can use TPZ for resize/upscale */
  32 +               return VC4_SCALING_TPZ;
  33 +       else if (3 * dst >= 2 * (src >> 16))
  34                 return VC4_SCALING_PPF;
  35         else
  36                 return VC4_SCALING_TPZ;
  37 @@ -560,12 +564,17 @@ static void vc4_write_tpz(struct vc4_pla
  38
  39         WARN_ON_ONCE(vc4->gen > VC4_GEN_6);
  40
  41 -       scale = src / dst;
  42 +       if ((dst << 16) < src) {
  43 +               scale = src / dst;
  44
  45 -       /* The specs note that while the reciprocal would be defined
  46 -        * as (1<<32)/scale, ~0 is close enough.
  47 -        */
  48 -       recip = ~0 / scale;
  49 +               /* The specs note that while the reciprocal would be defined
  50 +                * as (1<<32)/scale, ~0 is close enough.
  51 +                */
  52 +               recip = ~0 / scale;
  53 +       } else {
  54 +               scale = (1 << 16) + 1;
  55 +               recip = (1 << 16) - 1;
  56 +       }
  57
  58         vc4_dlist_write(vc4_state,
  59                         /*