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  1. 11 6月, 2014 3 次提交
  3. 05 6月, 2014 2 次提交
  5. 22 5月, 2014 2 次提交
  7. 21 5月, 2014 1 次提交
    • V
      drm/i915: Fix mmio vs. CS flip race on ILK+ · 75f7f3ec
      由 Ville Syrjälä 提交于 
      Starting from ILK, mmio flips also cause a flip done interrupt to be
signalled. This means if we first do a set_base and follow it
immediately with the CS flip, we might mistake the flip done interrupt
caused by the set_base as the flip done interrupt caused by the CS
flip.

The hardware has a flip counter which increments every time a mmio or
CS flip is issued. It basically counts the number of DSPSURF register
writes. This means we can sample the counter before we put the CS
flip into the ring, and then when we get a flip done interrupt we can
check whether the CS flip has actually performed the surface address
update, or if the interrupt was caused by a previous but yet
unfinished mmio flip.

Even with the flip counter we still have a race condition of the CS flip
base address update happens after the mmio flip done interrupt was
raised but not yet processed by the driver. When the interrupt is
eventually processed, the flip counter will already indicate that the
CS flip has been executed, but it would not actually complete until the
next start of vblank. We can use the DSPSURFLIVE register to check
whether the hardware is actually scanning out of the buffer we expect,
or if we managed hit this race window.

This covers all the cases where the CS flip actually changes the base
address. If the base address remains unchanged, we might still complete
the CS flip before it has actually completed. But since the address
didn't change anyway, the premature flip completion can't result in
userspace overwriting data that's still being scanned out.

CTG already has the flip counter and DSPSURFLIVE registers, and
although the flip done interrupt is still limited to CS flips alone,
the code now also checks the flip counter on CTG as well.

v2: s/dspsurf/gtt_offset/ (Chris)

Testcase: igt/kms_mmio_vs_cs_flip/setcrtc_vs_cs_flip
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=73027Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
[danvet: Add g4x_ prefix to flip_count_after_eq.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      75f7f3ec
  9. 20 5月, 2014 12 次提交
  11. 19 5月, 2014 2 次提交
  13. 16 5月, 2014 2 次提交
  15. 13 5月, 2014 6 次提交
  17. 07 5月, 2014 5 次提交
  19. 05 5月, 2014 3 次提交
  21. 25 4月, 2014 1 次提交
  23. 10 4月, 2014 1 次提交
    • P
      drm/i915: Add support for DRRS to switch RR · 439d7ac0
      由 Pradeep Bhat 提交于 
      This patch computes and stored 2nd M/N/TU for switching to different
refresh rate dynamically. PIPECONF_EDP_RR_MODE_SWITCH bit helps toggle
between alternate refresh rates programmed in 2nd M/N/TU registers.

v2: Daniel's review comments
Computing M2/N2 in compute_config and storing it in crtc_config

v3: Modified reference to edp_downclock and edp_downclock_avail based on the
changes made to move them from dev_private to intel_panel.

v4: Modified references to is_drrs_supported based on the changes made to
rename it to drrs_support.

v5: Jani's review comments
Removed superfluous return statements. Changed support for Gen 7 and above.
Corrected indentation. Re-structured the code which finds crtc and connector
from encoder. Changed some logs to be less verbose.

v6: Modifying i915_drrs to include only intel connector as intel_dp can be
derived from intel connector when required.

v7: As per internal review comments, acquiring mutex just before accessing
drrs RR. As per Chris's review comments, added documentation about the use
of locking in the function.

v8: Incorporated Jani's review comments.
Removed reference to edp_downclock.

v9: Jani's review comments. Modified comment in set_drrs. Changed index to
type edp_drrs_refresh_rate_type. Check if PSR is enabled before setting
registers fo DRRS.
Signed-off-by: NPradeep Bhat <pradeep.bhat@intel.com>
Signed-off-by: NVandana Kannan <vandana.kannan@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      439d7ac0