So updated vblank-rework pull request, now with the polish that Mario
requested applied (and reviewed by him). Also with backmerge like you've
requested for easier merging.
The neat thing this finally allows is to immediately disable the vblank
interrupt on the last drm_vblank_put if the hardware has perfectly
accurate vblank counter and timestamp readout support. On i915 that
required piles of small adjustements from Ville since depending upon the
platform and port the vblank happens at different scanout lines.
Of course this is fully opt-in and per-device (we need that since gen2
doesn't have a hw vblank counter).
* tag 'topic/vblank-rework-2014-09-12' of git://anongit.freedesktop.org/drm-intel: (22 commits)
drm: Clarify vblank ts/scanoutpos sampling #defines
drm: Simplify return value of drm_get_last_vbltimestamp
drm: Only update final vblank count when precise ts is available
drm: Really never disable vblank irqs for offdelay==0
drm: Use vblank_disable_and_save in drm_vblank_cleanup()
drm: Remove drm_vblank_cleanup from drm_vblank_init error path.
drm: Store the vblank timestamp when adjusting the counter during disable
drm: Fix confusing debug message in drm_update_vblank_count()
drm/i915: Update scanline_offset only for active crtcs
drm: Kick start vblank interrupts at drm_vblank_on()
drm/i915: Opt out of vblank disable timer on >gen2
drm: Add dev->vblank_disable_immediate flag
drm: Disable vblank interrupt immediately when drm_vblank_offdelay<0
drm: Fix race between drm_vblank_off() and drm_queue_vblank_event()
drm: Fix deadlock between event_lock and vbl_lock/vblank_time_lock
drm: Reduce the amount of dev->vblank[crtc] in the code
drm: Avoid random vblank counter jumps if the hardware counter has been reset
drm: Have the vblank counter account for the time between vblank irq disable and drm_vblank_off()
drm: Move drm_update_vblank_count()
drm: Don't clear vblank timestamps when vblank interrupt is disabled
...
************************************************************
* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
************************************************************
The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).
The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:
1. The DRM provides synchronized access to the graphics hardware via
the use of an optimized two-tiered lock.
2. The DRM enforces the DRI security policy for access to the graphics
hardware by only allowing authenticated X11 clients access to
restricted regions of memory.
3. The DRM provides a generic DMA engine, complete with multiple
queues and the ability to detect the need for an OpenGL context
switch.
4. The DRM is extensible via the use of small device-specific modules
that rely extensively on the API exported by the DRM module.
Documentation on the DRI is available from:
http://dri.freedesktop.org/wiki/Documentation
http://sourceforge.net/project/showfiles.php?group_id=387
http://dri.sourceforge.net/doc/
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://dri.sourceforge.net/doc/drm_low_level.html
Hardware Locking for the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/hardware_locking_low_level.html
A Security Analysis of the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/security_low_level.html
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