target/linux/brcm2708/patches-4.19/950-0572-drm-v3d-Invalidate-the-caches-from-the-outside-in.patch

   1 From e106cc466d4e85d294dd211984d9bc2aeb926f5a Mon Sep 17 00:00:00 2001
   2 From: Eric Anholt <eric@anholt.net>
   3 Date: Mon, 3 Dec 2018 14:24:38 -0800
   4 Subject: [PATCH 572/773] drm/v3d: Invalidate the caches from the outside in.
   5
   6 This would be a fairly obscure race, but let's make sure we don't ever
   7 lose it.
   8
   9 Signed-off-by: Eric Anholt <eric@anholt.net>
  10 Link: https://patchwork.freedesktop.org/patch/msgid/20181203222438.25417-6-eric@anholt.net
  11 Reviewed-by: Dave Emett <david.emett@broadcom.com>
  12 (cherry picked from commit aa5beec32e8b78bfcf621e3c3daebfb1644b6365)
  13 ---
  14  drivers/gpu/drm/v3d/v3d_gem.c | 8 ++++++--
  15  1 file changed, 6 insertions(+), 2 deletions(-)
  16
  17 --- a/drivers/gpu/drm/v3d/v3d_gem.c
  18 +++ b/drivers/gpu/drm/v3d/v3d_gem.c
  19 @@ -171,11 +171,15 @@ v3d_invalidate_slices(struct v3d_dev *v3
  20  void
  21  v3d_invalidate_caches(struct v3d_dev *v3d)
  22  {
  23 +       /* Invalidate the caches from the outside in.  That way if
  24 +        * another CL's concurrent use of nearby memory were to pull
  25 +        * an invalidated cacheline back in, we wouldn't leave stale
  26 +        * data in the inner cache.
  27 +        */
  28         v3d_flush_l3(v3d);
  29 -
  30         v3d_invalidate_l2c(v3d, 0);
  31 -       v3d_invalidate_slices(v3d, 0);
  32         v3d_flush_l2t(v3d, 0);
  33 +       v3d_invalidate_slices(v3d, 0);
  34  }
  35
  36  static void