[PATCH v4 0/4] drm/vc4: Add a load tracker

[Paul Kocialkowski <paul.kocialkowski@bootlin.com>]

Hi,

Here is a fourth iteration of the VC4 load tracking series, which was
initially developed by Boris Brezillon and that I have now taken over.

This new iteration takes in account comments from v3 and comes with a
new approach for avoiding underrun reports when reconfiguring the
pipeline. It is now based on detection instead of delaying the underrun
interrupt unmasking.

It can be tested with a dedicated IGT GPU Tools series:
  VC4 load tracker testing

Changes since v3:
* Returned IRQ_NONE for short line interrupt to avoid storm;
* Made register definitions with per-channel offsets more direct;
* cleaned all IRQ fields instead of writing back the status bit as
  advised by docs;
* Reworked first commit's message;
* Removed in-commit changelogs with inconsistent revision numbers;
* Removed explicit wait for sync before unmasking underrun interrupt;
* Checked that the display lists are synced before reporting underrun;

Cheers,

Paul

Boris Brezillon (2):
  drm/vc4: Report HVS underrun errors
  drm/vc4: Add a load tracker to prevent HVS underflow errors

Paul Kocialkowski (2):
  drm/vc4: Detect and ignore underruns caused by out-of-sync dlists
  drm/vc4: Add a debugfs entry to disable/enable the load tracker

 drivers/gpu/drm/vc4/vc4_debugfs.c |  10 +++
 drivers/gpu/drm/vc4/vc4_drv.c     |   1 +
 drivers/gpu/drm/vc4/vc4_drv.h     |  32 ++++++++
 drivers/gpu/drm/vc4/vc4_hvs.c     | 123 ++++++++++++++++++++++++++++++
 drivers/gpu/drm/vc4/vc4_kms.c     | 116 +++++++++++++++++++++++++++-
 drivers/gpu/drm/vc4/vc4_plane.c   |  57 ++++++++++++++
 drivers/gpu/drm/vc4/vc4_regs.h    |  51 ++++---------
 7 files changed, 354 insertions(+), 36 deletions(-)

-- 
2.20.1