Re: [PATCH 09/11] drm/i915: Introduce pin_params.needs_fence

[Jani Nikula <jani.nikula@linux.intel.com>]

On Thu, 16 Apr 2026, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Add a new flag pin_params.needs_fencel to inform the pinning

*needs_fence

> code that the display needs a fence for tiled scanout.
>
> The goal is to eliminate all display specific stuff from
> the low level pinning code.

Again, I find it just a little magical that .needs_fence is only
initialized in certain code paths, with the implementation detail
knowledge where the member is used. E.g. in this case out_fence_id !=
NULL.

Regardless,

Reviewed-by: Jani Nikula <jani.nikula@intel.com>


>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_fb_pin.h | 1 +
>  drivers/gpu/drm/i915/i915_fb_pin.c          | 4 ++--
>  2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_fb_pin.h b/drivers/gpu/drm/i915/display/intel_fb_pin.h
> index 3e37e9874f50..95f83bf7411f 100644
> --- a/drivers/gpu/drm/i915/display/intel_fb_pin.h
> +++ b/drivers/gpu/drm/i915/display/intel_fb_pin.h
> @@ -22,6 +22,7 @@ struct intel_fb_pin_params {
>  	bool needs_cpu_lmem_access;
>  	bool needs_low_address;
>  	bool needs_physical;
> +	bool needs_fence;
>  };
>  
>  struct i915_vma *
> diff --git a/drivers/gpu/drm/i915/i915_fb_pin.c b/drivers/gpu/drm/i915/i915_fb_pin.c
> index a8ed888183cb..5060ec8c76ca 100644
> --- a/drivers/gpu/drm/i915/i915_fb_pin.c
> +++ b/drivers/gpu/drm/i915/i915_fb_pin.c
> @@ -112,7 +112,6 @@ intel_fb_pin_to_ggtt(const struct drm_framebuffer *fb,
>  		     const struct intel_fb_pin_params *pin_params,
>  		     int *out_fence_id)
>  {
> -	struct intel_display *display = to_intel_display(fb->dev);
>  	struct drm_i915_private *i915 = to_i915(fb->dev);
>  	struct drm_gem_object *_obj = intel_fb_bo(fb);
>  	struct drm_i915_gem_object *obj = to_intel_bo(_obj);
> @@ -188,7 +187,7 @@ intel_fb_pin_to_ggtt(const struct drm_framebuffer *fb,
>  		 * mode that matches the user configuration.
>  		 */
>  		ret = i915_vma_pin_fence(vma);
> -		if (ret != 0 && intel_plane_needs_fence(display)) {
> +		if (ret != 0 && pin_params->needs_fence) {
>  			i915_vma_unpin(vma);
>  			goto err_unpin;
>  		}
> @@ -272,6 +271,7 @@ int intel_plane_pin_fb(struct intel_plane_state *plane_state,
>  			.needs_cpu_lmem_access = intel_fb_needs_cpu_access(&fb->base),
>  			.needs_low_address = intel_plane_needs_low_address(display),
>  			.needs_physical = intel_plane_needs_physical(plane),
> +			.needs_fence = intel_plane_needs_fence(display),
>  		};
>  		int fence_id = -1;

-- 
Jani Nikula, Intel