[Intel-gfx] [PATCH 0/5] drm/i915: Optimize plane updates a bit

ville.syrjala at linux.intel.com ville.syrjala at linux.intel.com
Thu Mar 9 15:44:29 UTC 2017


From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Now that commit e1edbd44e23b ("drm/i915: Complain if we take too
long under vblank evasion.") has expose just how badly we suck,
it seems like a good time to optimize things a little bit.

Prior to this one of my VLV machines exceed the 100 usec vblank
evade deadline pretty regularly, and at ever boot I was hitting
numbers as high as 500 usec. Granted that was with lockdep and
all kinds of other debug things enabled. After these changes
things seem stay below the 33 usec mark, and with all that debug
junk enabled we seem to staying below 22 usec.

Note that I was testing single plane updates mostly, so I'm
not 100% sure multi plane updates couldn't still exceed the
deadline. That will need to be checked.

Ville Syrjälä (5):
  drm/i915: Use I915_READ_FW in i915_get_vblank_counter()
  drm/i915: s/__raw_i915_read32/I915_READ_FW/ in the SKL+ scanline read
    w/a
  drm/i915: Organize plane register writes into tighter bunches
  drm/i915: Use I915_READ_FW for plane updates
  drm/i915: Optimize VLV/CHV display FIFO updates

 drivers/gpu/drm/i915/i915_drv.c      |   1 -
 drivers/gpu/drm/i915/i915_drv.h      |   3 -
 drivers/gpu/drm/i915/i915_irq.c      |  14 +-
 drivers/gpu/drm/i915/intel_display.c | 176 ++++++++++++++---------
 drivers/gpu/drm/i915/intel_pm.c      |  36 +++--
 drivers/gpu/drm/i915/intel_sprite.c  | 269 ++++++++++++++++++++---------------
 6 files changed, 290 insertions(+), 209 deletions(-)

-- 
2.10.2



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