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| author | Karthik B S <karthik.b.s@intel.com> | 2020-09-21 14:02:09 +0300 |
|---|---|---|
| committer | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2020-09-28 14:12:49 +0300 |
| commit | 6914c9685e0a2376c128a3519b5b5e0619bb5f2d (patch) | |
| tree | 49828564a692be9509f058f7193faf42d31ccf81 | |
| parent | e5cb1afba46d0a2c01605483e800f8231362022b (diff) | |
| download | linux-6914c9685e0a2376c128a3519b5b5e0619bb5f2d.tar.xz | |
Documentation/gpu: Add asynchronous flip documentation for i915
Add the details of the implementation of asynchronous flips for i915.
v7: -Rebased.
v8: -Rebased.
v9: -Rebased.
v10: Move all documentation changes to this patch. (Ville)
Signed-off-by: Karthik B S <karthik.b.s@intel.com>
Signed-off-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200921110210.21182-8-karthik.b.s@intel.com
| -rw-r--r-- | Documentation/gpu/i915.rst | 6 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_display.c | 18 |
2 files changed, 24 insertions, 0 deletions
diff --git a/Documentation/gpu/i915.rst b/Documentation/gpu/i915.rst index 33cc6ddf8f64..84ead508f7ad 100644 --- a/Documentation/gpu/i915.rst +++ b/Documentation/gpu/i915.rst @@ -118,6 +118,12 @@ Atomic Plane Helpers .. kernel-doc:: drivers/gpu/drm/i915/display/intel_atomic_plane.c :internal: +Asynchronous Page Flip +---------------------- + +.. kernel-doc:: drivers/gpu/drm/i915/display/intel_display.c + :doc: asynchronous flip implementation + Output Probing -------------- diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index b23fd5232ee6..a012d48d5e3e 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -14929,6 +14929,24 @@ static bool intel_cpu_transcoders_need_modeset(struct intel_atomic_state *state, return false; } +/** + * DOC: asynchronous flip implementation + * + * Asynchronous page flip is the implementation for the DRM_MODE_PAGE_FLIP_ASYNC + * flag. Currently async flip is only supported via the drmModePageFlip IOCTL. + * Correspondingly, support is currently added for primary plane only. + * + * Async flip can only change the plane surface address, so anything else + * changing is rejected from the intel_atomic_check_async() function. + * Once this check is cleared, flip done interrupt is enabled using + * the skl_enable_flip_done() function. + * + * As soon as the surface address register is written, flip done interrupt is + * generated and the requested events are sent to the usersapce in the interrupt + * handler itself. The timestamp and sequence sent during the flip done event + * correspond to the last vblank and have no relation to the actual time when + * the flip done event was sent. + */ static int intel_atomic_check_async(struct intel_atomic_state *state) { struct drm_i915_private *i915 = to_i915(state->base.dev); |