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Tomeu Vizoso
authored
The core provides now an ABI to userspace for generation of frame CRCs,
so implement the ->set_crc_source() callback and reuse as much code as
possible with the previous ABI implementation.
When handling the pageflip interrupt, we skip 1 or 2 frames depending on
the HW because they contain wrong values. For the legacy ABI for
generating frame CRCs, this was done in userspace but now that we have a
generic ABI it's better if it's not exposed by the kernel.
v2:
- Leave the legacy implementation in place as the ABI implementation
in the core is incompatible with it.
v3:
- Use the "cooked" vblank counter so we have a whole 32 bits.
- Make sure we don't mess with the state of the legacy CRC capture
ABI implementation.
v4:
- Keep use of get_vblank_counter as in the legacy code, will be
changed in a followup commit.
v5:
- Skip first frame or two as it's known that they contain wrong
data.
- A few fixes suggested by Emil Velikov.
v6:
- Rework programming of the HW registers to preserve previous
behavior.
v7:
- Address whitespace issue.
- Added a comment on why in the implementation of the new ABI we
skip the 1st or 2nd frames.
v9:
- Add stub for intel_crtc_set_crc_source.
v12:
- Rebased.
- Remove stub for intel_crtc_set_crc_source and instead set the
callback to NULL (Jani Nikula).
v15:
- Rebased.
Signed-off-by: 
Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: 
Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: 
Robert Foss <robert.foss@collabora.com>
irq
Signed-off-by: 
Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170110134305.26326-2-tomeu.vizoso@collabora.com