Re: [PATCH 06/16] drm/i915: Introduce i915_fb_pin_ggtt_(un)pin()

Jani Nikula
2026-04-24T09:59:39Z

On Thu, 23 Apr 2026, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Extract the inner DPT parts of intel_plane_(un)pin() into the
> i915_fb_pin_ggtt_(un)pin(). These will become part of the new
> fb_pin parent interface.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

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

> ---
> drivers/gpu/drm/i915/i915_fb_pin.c | 68 +++++++++++++++++++-----------
> 1 file changed, 44 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_fb_pin.c b/drivers/gpu/drm/i915/i915_fb_pin.c
> index 0019f570d843..e14d2c1fb81f 100644
> --- a/drivers/gpu/drm/i915/i915_fb_pin.c
> +++ b/drivers/gpu/drm/i915/i915_fb_pin.c
> @@ -257,6 +257,41 @@ intel_plane_fb_vtd_guard(const struct intel_plane_state *plane_state)
> plane_state->hw.rotation);
> }
>
> +static int i915_fb_pin_ggtt_pin(struct drm_gem_object *obj,
> + const struct intel_fb_pin_params *pin_params,
> + struct i915_vma **out_ggtt_vma,
> + u32 *out_offset,
> + int *out_fence_id)
> +{
> + struct i915_vma *ggtt_vma;
> +
> + ggtt_vma = intel_fb_pin_to_ggtt(obj, pin_params, out_fence_id);
> + if (IS_ERR(ggtt_vma))
> + return PTR_ERR(ggtt_vma);
> +
> + *out_ggtt_vma = ggtt_vma;
> +
> + /*
> + * Pre-populate the dma address before we enter the vblank
> + * evade critical section as i915_gem_object_get_dma_address()
> + * will trigger might_sleep() even if it won't actually sleep,
> + * which is the case when the fb has already been pinned.
> + */
> + if (pin_params->needs_physical)
> + *out_offset = i915_gem_object_get_dma_address(to_intel_bo(obj), 0);
> + else
> + *out_offset = i915_ggtt_offset(ggtt_vma);
> +
> + return 0;
> +}
> +
> +static void i915_fb_pin_ggtt_unpin(struct i915_vma *ggtt_vma,
> + int fence_id)
> +{
> + if (ggtt_vma)
> + intel_fb_unpin_vma(ggtt_vma, fence_id);
> +}
> +
> static int i915_fb_pin_dpt_pin(struct drm_gem_object *obj, struct intel_dpt *dpt,
> const struct intel_fb_pin_params *pin_params,
> struct i915_vma **out_dpt_vma,
> @@ -325,24 +360,11 @@ int intel_plane_pin_fb(struct intel_plane_state *plane_state,
> .needs_fence = intel_plane_needs_fence(display),
> };
>
> - ggtt_vma = intel_fb_pin_to_ggtt(intel_fb_bo(&fb->base), &pin_params,
> - intel_plane_uses_fence(plane_state) ? &fence_id : NULL);
> - if (IS_ERR(ggtt_vma))
> - return PTR_ERR(ggtt_vma);
> -
> - /*
> - * Pre-populate the dma address before we enter the vblank
> - * evade critical section as i915_gem_object_get_dma_address()
> - * will trigger might_sleep() even if it won't actually sleep,
> - * which is the case when the fb has already been pinned.
> - */
> - if (intel_plane_needs_physical(plane)) {
> - struct drm_i915_gem_object *obj = to_intel_bo(intel_fb_bo(&fb->base));
> -
> - offset = i915_gem_object_get_dma_address(obj, 0);
> - } else {
> - offset = i915_ggtt_offset(ggtt_vma);
> - }
> + ret = i915_fb_pin_ggtt_pin(intel_fb_bo(&fb->base),
> + &pin_params, &ggtt_vma, &offset,
> + intel_plane_uses_fence(plane_state) ? &fence_id : NULL);
> + if (ret)
> + return ret;
> } else {
> struct intel_fb_pin_params pin_params = {
> .view = &plane_state->view.gtt,
> @@ -371,13 +393,11 @@ void intel_plane_unpin_fb(struct intel_plane_state *old_plane_state)
> to_intel_framebuffer(old_plane_state->hw.fb);
>
> if (!intel_fb_uses_dpt(&fb->base)) {
> - struct i915_vma *vma;
> + i915_fb_pin_ggtt_unpin(old_plane_state->ggtt_vma,
> + old_plane_state->fence_id);
>
> - vma = fetch_and_zero(&old_plane_state->ggtt_vma);
> - if (vma) {
> - intel_fb_unpin_vma(vma, old_plane_state->fence_id);
> - old_plane_state->fence_id = -1;
> - }
> + old_plane_state->ggtt_vma = NULL;
> + old_plane_state->fence_id = -1;
> } else {
> i915_fb_pin_dpt_unpin(fb->dpt,
> old_plane_state->dpt_vma,

--
Jani Nikula, Intel