[PATCH v2 0/5] drm/tilcdc: Fix cpufreq transition related race + cleanup

Jyri Sarha jsarha at ti.com
Tue Sep 6 20:59:20 UTC 2016


Changes since v1:
- Use drm_modeset_lock/unlock_crtc() instead of taking mode config mutex
- Rewrote decsription for old "drm/tilcdc: Add tilcdc_crtc_set_clk() and
  cleanup cpufreq_transition()" which now called "drm/tilcdc: Clean up LCDC
  functional clock rate setting code"
- Dropped "drm/tilcdc: Add mutex to protect crtc enable and disable routines"
- Added "drm/tilcdc: Flush flip-work workqueue before drm_flip_work_cleanup()"
- Added "drm/tilcdc: Remove unnecessary tilcdc_crtc_disable() from
  	 tilcdc_unload()"
- Added "drm/tilcdc: WARN if CRTC is touched without CRTC lock"

There was a race between mode_set_nofb() and cpufreq_transition()
calling tilcdc_crtc_update_clk() without locking.

The first patch fixes the race in with a minimal change by taking
the drm CRTC lock for the duration of the clock update.

The second patch goes a step forward and cleans up the clock setting
code a bit.

BR,
Jyri


Jyri Sarha (5):
  drm/tilcdc: Take crtc modeset lock while updating the crtc clock rate
  drm/tilcdc: Clean up LCDC functional clock rate setting code
  drm/tilcdc: Flush flip-work workqueue before drm_flip_work_cleanup()
  drm/tilcdc: Remove unnecessary tilcdc_crtc_disable() from
    tilcdc_unload()
  drm/tilcdc: WARN if CRTC is touched without CRTC lock

 drivers/gpu/drm/tilcdc/tilcdc_crtc.c | 91 +++++++++++++++++++++++-------------
 drivers/gpu/drm/tilcdc/tilcdc_drv.c  | 12 ++---
 drivers/gpu/drm/tilcdc/tilcdc_drv.h  |  1 -
 3 files changed, 62 insertions(+), 42 deletions(-)

-- 
1.9.1



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