[PATCH 4/6] drm/v3d: Drop the wait for L2T flush to complete.

From: Eric Anholt
Date: Fri Nov 30 2018 - 19:58:08 EST


According to Dave, once you've started an L2T flush, all L2T accesses
will be blocked until the flush completes. This fixes a consistent
3-4ms stall between the ioctl and running the job, and 3DMMES Taiji
goes from 27fps to 110fps.

Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
---
drivers/gpu/drm/v3d/v3d_gem.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
index cc4d025b01e0..0bd6892e3044 100644
--- a/drivers/gpu/drm/v3d/v3d_gem.c
+++ b/drivers/gpu/drm/v3d/v3d_gem.c
@@ -146,10 +146,6 @@ v3d_flush_l2t(struct v3d_dev *v3d, int core)
V3D_CORE_WRITE(core, V3D_CTL_L2TCACTL,
V3D_L2TCACTL_L2TFLS |
V3D_SET_FIELD(V3D_L2TCACTL_FLM_FLUSH, V3D_L2TCACTL_FLM));
- if (wait_for(!(V3D_CORE_READ(core, V3D_CTL_L2TCACTL) &
- V3D_L2TCACTL_L2TFLS), 100)) {
- DRM_ERROR("Timeout waiting for L2T flush\n");
- }
}

/* Invalidates the slice caches. These are read-only caches. */
--
2.20.0.rc1