[Intel-gfx] [PATCH v10 3/8] drm/i915: Add checks specific to async flips

Karthik B S karthik.b.s at intel.com
Mon Sep 21 10:49:28 UTC 2020



On 9/18/2020 5:21 PM, Ville Syrjälä wrote:
> On Fri, Sep 18, 2020 at 02:32:34PM +0530, Karthik B S wrote:
>> If flip is requested on any other plane, reject it.
>>
>> Make sure there is no change in fbc, offset and framebuffer modifiers
>> when async flip is requested.
>>
>> If any of these are modified, reject async flip.
>>
>> v2: -Replace DRM_ERROR (Paulo)
>>      -Add check for changes in OFFSET, FBC, RC(Paulo)
>>
>> v3: -Removed TODO as benchmarking tests have been run now.
>>
>> v4: -Added more state checks for async flip (Ville)
>>      -Moved intel_atomic_check_async to the end of intel_atomic_check
>>       as the plane checks needs to pass before this. (Ville)
>>      -Removed crtc_state->enable_fbc check. (Ville)
>>      -Set the I915_MODE_FLAG_GET_SCANLINE_FROM_TIMESTAMP flag for async
>>       flip case as scanline counter is not reliable here.
>>
>> v5: -Fix typo and other check patch errors seen in CI
>>       in 'intel_atomic_check_async' function.
>>
>> v6: -Don't call intel_atomic_check_async multiple times. (Ville)
>>      -Remove the check for n_planes in intel_atomic_check_async
>>      -Added documentation for async flips. (Paulo)
>>
>> v7: -Replace 'intel_plane' with 'plane'. (Ville)
>>      -Replace all uapi.foo as hw.foo. (Ville)
>>      -Do not use intel_wm_need_update function. (Ville)
>>      -Add destination coordinate check. (Ville)
>>      -Do not allow async flip with linear buffer
>>       on older hw as it has issues with this. (Ville)
>>      -Remove break after intel_atomic_check_async. (Ville)
>>
>> v8: -Rebased.
>>
>> v9: -Replace DRM_DEBUG_KMS with drm_dbg_kms(). (Ville)
>>      -Fix comment formatting. (Ville)
>>      -Remove gen specific checks. (Ville)
>>      -Remove irrelevant FB size check. (Ville)
>>      -Add missing stride check. (Ville)
>>      -Use drm_rect_equals() instead of individual checks. (Ville)
>>      -Call intel_atomic_check_async before state dump. (Ville)
>>
>> v10: -Fix the checkpatch errors seen on CI.
>>
>> Signed-off-by: Karthik B S <karthik.b.s at intel.com>
>> Signed-off-by: Vandita Kulkarni <vandita.kulkarni at intel.com>
>> ---
>>   drivers/gpu/drm/i915/display/intel_display.c | 137 +++++++++++++++++++
>>   1 file changed, 137 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
>> index 30e8908ee263..7327ed4a04f8 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display.c
>> +++ b/drivers/gpu/drm/i915/display/intel_display.c
>> @@ -14877,6 +14877,137 @@ 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);
>> +	struct intel_crtc_state *old_crtc_state, *new_crtc_state;
>> +	struct intel_plane_state *new_plane_state, *old_plane_state;a
> 
> All plane/crtc states can be const I believe.
> 

Thanks for the review.
Sure, I'll update this.
>> +	struct intel_crtc *crtc;
>> +	struct intel_plane *plane;
>> +	int i;
>> +
>> +	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
>> +					    new_crtc_state, i) {
>> +		if (needs_modeset(new_crtc_state)) {
>> +			drm_dbg_kms(&i915->drm, "Modeset Required. Async flip not supported\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (!new_crtc_state->hw.active) {
>> +			drm_dbg_kms(&i915->drm, "CRTC inactive\n");
>> +			return -EINVAL;
>> +		}
>> +		if (old_crtc_state->active_planes != new_crtc_state->active_planes) {
>> +			drm_dbg_kms(&i915->drm,
>> +				    "Active planes cannot be changed during async flip\n");
>> +			return -EINVAL;
>> +		}
>> +	}
>> +
>> +	for_each_oldnew_intel_plane_in_state(state, plane, old_plane_state,
>> +					     new_plane_state, i) {
>> +		/*
>> +		 * TODO: Async flip is only supported through the page flip IOCTL
>> +		 * as of now. So support currently added for primary plane only.
>> +		 * Support for other planes on platforms on which supports
>> +		 * this(vlv/chv and icl+) should be added when async flip is
>> +		 * enabled in the atomic IOCTL path.
>> +		 */
>> +		if (plane->id != PLANE_PRIMARY)
>> +			return -EINVAL;
>> +
>> +		/*
>> +		 * FIXME: This check is kept generic for all platforms.
>> +		 * Need to verify this for all gen9 and gen10 platforms to enable
>> +		 * this selectively if required.
>> +		 */
>> +		if (!(new_plane_state->hw.fb->modifier != I915_FORMAT_MOD_X_TILED ||
>> +		      new_plane_state->hw.fb->modifier != I915_FORMAT_MOD_Y_TILED ||
>> +		      new_plane_state->hw.fb->modifier != I915_FORMAT_MOD_Yf_TILED)) {
> 
> I suspect a switch() would be less ugly
> 

Sure, I'll change this to switch().

> looks good otherwise
> Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 

Thanks,
Karthik.B.S
>> +			drm_dbg_kms(&i915->drm,
>> +				    "Linear memory/CCS does not support async flips\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->color_plane[0].stride !=
>> +		    new_plane_state->color_plane[0].stride) {
>> +			drm_dbg_kms(&i915->drm, "Stride cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->hw.fb->modifier !=
>> +		    new_plane_state->hw.fb->modifier) {
>> +			drm_dbg_kms(&i915->drm,
>> +				    "Framebuffer modifiers cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->hw.fb->format !=
>> +		    new_plane_state->hw.fb->format) {
>> +			drm_dbg_kms(&i915->drm,
>> +				    "Framebuffer format cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->hw.rotation !=
>> +		    new_plane_state->hw.rotation) {
>> +			drm_dbg_kms(&i915->drm, "Rotation cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (!drm_rect_equals(&old_plane_state->uapi.src, &new_plane_state->uapi.src) ||
>> +		    !drm_rect_equals(&old_plane_state->uapi.dst, &new_plane_state->uapi.dst)) {
>> +			drm_dbg_kms(&i915->drm,
>> +				    "Plane size/co-ordinates cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->hw.alpha != new_plane_state->hw.alpha) {
>> +			drm_dbg_kms(&i915->drm, "Alpha value cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->hw.pixel_blend_mode !=
>> +		    new_plane_state->hw.pixel_blend_mode) {
>> +			drm_dbg_kms(&i915->drm,
>> +				    "Pixel blend mode cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->hw.color_encoding != new_plane_state->hw.color_encoding) {
>> +			drm_dbg_kms(&i915->drm,
>> +				    "Color encoding cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (old_plane_state->hw.color_range != new_plane_state->hw.color_range) {
>> +			drm_dbg_kms(&i915->drm, "Color range cannot be changed in async flip\n");
>> +			return -EINVAL;
>> +		}
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>>   /**
>>    * intel_atomic_check - validate state object
>>    * @dev: drm device
>> @@ -15045,6 +15176,12 @@ static int intel_atomic_check(struct drm_device *dev,
>>   
>>   	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
>>   					    new_crtc_state, i) {
>> +		if (new_crtc_state->uapi.async_flip) {
>> +			ret = intel_atomic_check_async(state);
>> +			if (ret)
>> +				goto fail;
>> +		}
>> +
>>   		if (!needs_modeset(new_crtc_state) &&
>>   		    !new_crtc_state->update_pipe)
>>   			continue;
>> -- 
>> 2.22.0
> 


More information about the Intel-gfx mailing list