Re: [PATCH 16/16] drm/i915: Consolidate the intel_plane_(un)pin_fb() implementations

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Apr 24, 2026 at 04:30:40PM +0300, Jani Nikula wrote:
> On Thu, 23 Apr 2026, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> >
> > Currently i915 and each implement their own versions of
> 
> and xe?
> 
> > intel_plane_(un)pin(). Now that we have the fb_pin parent
> > interface we can consolidate this to a single implementation.
> >
> > The result is a mixture of the i915 and xe implementations.
> > The reuse_vma() hack comes from xe (and i915 doesn't implement
> > that part of the parent interface, and the pin_params are
> > taken from i915 since the platforms supported by i915 need
> > more things.
> 
> One somewhat complicated and spread out comment inline. Other than that,
> 
> Reviewed-by: Jani Nikula <jani.nikula@intel.com>
> 
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_cursor.c |   1 -
> >  drivers/gpu/drm/i915/display/intel_fb_pin.h |  27 -----
> >  drivers/gpu/drm/i915/display/intel_plane.c  | 118 +++++++++++++++++++-
> >  drivers/gpu/drm/i915/display/intel_plane.h  |   3 +
> >  drivers/gpu/drm/i915/i915_fb_pin.c          | 116 +------------------
> >  drivers/gpu/drm/xe/display/xe_fb_pin.c      |  82 +-------------
> >  6 files changed, 126 insertions(+), 221 deletions(-)
> >  delete mode 100644 drivers/gpu/drm/i915/display/intel_fb_pin.h
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_cursor.c b/drivers/gpu/drm/i915/display/intel_cursor.c
> > index 18d1014de361..52347668f27d 100644
> > --- a/drivers/gpu/drm/i915/display/intel_cursor.c
> > +++ b/drivers/gpu/drm/i915/display/intel_cursor.c
> > @@ -21,7 +21,6 @@
> >  #include "intel_display_utils.h"
> >  #include "intel_display_wa.h"
> >  #include "intel_fb.h"
> > -#include "intel_fb_pin.h"
> >  #include "intel_frontbuffer.h"
> >  #include "intel_plane.h"
> >  #include "intel_psr.h"
> > diff --git a/drivers/gpu/drm/i915/display/intel_fb_pin.h b/drivers/gpu/drm/i915/display/intel_fb_pin.h
> > deleted file mode 100644
> > index 6ff17d3e2cf5..000000000000
> > --- a/drivers/gpu/drm/i915/display/intel_fb_pin.h
> > +++ /dev/null
> > @@ -1,27 +0,0 @@
> > -/* SPDX-License-Identifier: MIT */
> > -/*
> > - * Copyright © 2021 Intel Corporation
> > - */
> > -
> > -#ifndef __INTEL_FB_PIN_H__
> > -#define __INTEL_FB_PIN_H__
> > -
> > -#include <linux/types.h>
> > -
> > -struct drm_gem_object;
> > -struct i915_vma;
> > -struct intel_fb_pin_params;
> > -struct intel_plane_state;
> > -struct i915_gtt_view;
> > -struct iosys_map;
> > -
> > -struct i915_vma *
> > -intel_fb_pin_to_ggtt(struct drm_gem_object *obj,
> > -		     const struct intel_fb_pin_params *pin_params,
> > -		     int *out_fence_id);
> > -
> > -int intel_plane_pin_fb(struct intel_plane_state *new_plane_state,
> > -		       const struct intel_plane_state *old_plane_state);
> > -void intel_plane_unpin_fb(struct intel_plane_state *old_plane_state);
> > -
> > -#endif
> > diff --git a/drivers/gpu/drm/i915/display/intel_plane.c b/drivers/gpu/drm/i915/display/intel_plane.c
> > index e50e1a15410a..f132fa955d21 100644
> > --- a/drivers/gpu/drm/i915/display/intel_plane.c
> > +++ b/drivers/gpu/drm/i915/display/intel_plane.c
> > @@ -44,6 +44,7 @@
> >  #include <drm/drm_gem_atomic_helper.h>
> >  #include <drm/drm_panic.h>
> >  #include <drm/drm_print.h>
> > +#include <drm/intel/display_parent_interface.h>
> >  
> >  #include "i9xx_plane_regs.h"
> >  #include "intel_cdclk.h"
> > @@ -53,7 +54,6 @@
> >  #include "intel_display_trace.h"
> >  #include "intel_display_types.h"
> >  #include "intel_fb.h"
> > -#include "intel_fb_pin.h"
> >  #include "intel_fbdev.h"
> >  #include "intel_parent.h"
> >  #include "intel_plane.h"
> > @@ -1191,6 +1191,122 @@ int intel_plane_check_src_coordinates(struct intel_plane_state *plane_state)
> >  	return 0;
> >  }
> >  
> > +static unsigned int
> > +intel_plane_fb_min_alignment(const struct intel_plane_state *plane_state)
> > +{
> > +	const struct intel_framebuffer *fb = to_intel_framebuffer(plane_state->hw.fb);
> > +
> > +	return fb->min_alignment;
> 
> (1)
> 
> > +}
> > +
> > +static unsigned int
> > +intel_plane_fb_min_phys_alignment(const struct intel_plane_state *plane_state)
> > +{
> > +	struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
> > +	const struct drm_framebuffer *fb = plane_state->hw.fb;
> > +
> > +	if (!intel_plane_needs_physical(plane))
> > +		return 0;
> > +
> > +	return plane->min_alignment(plane, fb, 0);
> > +}
> > +
> > +static unsigned int
> > +intel_plane_fb_vtd_guard(const struct intel_plane_state *plane_state)
> > +{
> > +	return intel_fb_view_vtd_guard(plane_state->hw.fb,
> > +				       &plane_state->view,
> > +				       plane_state->hw.rotation);
> > +}
> > +
> > +int intel_plane_pin_fb(struct intel_plane_state *plane_state,
> > +		       const struct intel_plane_state *old_plane_state)
> > +{
> > +	struct intel_display *display = to_intel_display(plane_state);
> > +	struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
> > +	const struct intel_framebuffer *fb =
> > +		to_intel_framebuffer(plane_state->hw.fb);
> > +	const struct intel_framebuffer *old_fb =
> > +		to_intel_framebuffer(old_plane_state->hw.fb);
> > +	struct i915_vma *ggtt_vma = NULL;
> > +	struct i915_vma *dpt_vma = NULL;
> > +	int fence_id = -1;
> > +	u32 offset = 0;
> > +	int ret;
> > +
> > +	/* hack for xe since it can't keep track of vmas properly */
> > +	ggtt_vma = intel_parent_fb_pin_reuse_vma(display,
> > +						 old_plane_state->ggtt_vma,
> > +						 intel_fb_bo(&old_fb->base),
> > +						 &old_plane_state->view.gtt,
> > +						 intel_fb_bo(&fb->base),
> > +						 &plane_state->view.gtt,
> > +						 &offset);
> > +	if (ggtt_vma)
> > +		goto got_vma;
> > +
> > +	if (!intel_fb_uses_dpt(&fb->base)) {
> > +		struct intel_fb_pin_params pin_params = {
> > +			.view = &plane_state->view.gtt,
> > +			.alignment = intel_plane_fb_min_alignment(plane_state),
> 
> So this is equal to i915, and uses (1) above.
> 
> > +			.phys_alignment = intel_plane_fb_min_phys_alignment(plane_state),
> > +			.vtd_guard = intel_plane_fb_vtd_guard(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),
> > +		};
> > +
> > +		ret = intel_parent_fb_pin_ggtt_pin(display, intel_fb_bo(&fb->base),
> > +						   &pin_params, &ggtt_vma, &offset,
> > +						   intel_plane_uses_fence(plane_state) ? &fence_id : NULL);
> > +	} else {
> > +		struct intel_fb_pin_params pin_params = {
> > +			.view = &plane_state->view.gtt,
> > +			.alignment = intel_plane_fb_min_alignment(plane_state),
> > +			.needs_cpu_lmem_access = intel_fb_needs_cpu_access(&fb->base),
> > +		};
> > +
> > +		ret = intel_parent_fb_pin_dpt_pin(display, intel_fb_bo(&fb->base),
> > +						  fb->dpt, &pin_params,
> > +						  &dpt_vma, &ggtt_vma, &offset);
> > +	}
> > +	if (ret)
> > +		return ret;
> > +
> > +got_vma:
> > +	plane_state->dpt_vma = dpt_vma;
> > +	plane_state->ggtt_vma = ggtt_vma;
> > +	plane_state->fence_id = fence_id;
> > +
> > +	plane_state->surf = offset + plane->surf_offset(plane_state);
> > +
> > +	return 0;
> > +}
> > +
> > +void intel_plane_unpin_fb(struct intel_plane_state *old_plane_state)
> > +{
> > +	struct intel_display *display = to_intel_display(old_plane_state);
> > +	const struct intel_framebuffer *fb =
> > +		to_intel_framebuffer(old_plane_state->hw.fb);
> > +
> > +	if (!intel_fb_uses_dpt(&fb->base)) {
> > +		intel_parent_fb_pin_ggtt_unpin(display,
> > +					       old_plane_state->ggtt_vma,
> > +					       old_plane_state->fence_id);
> > +
> > +		old_plane_state->ggtt_vma = NULL;
> > +		old_plane_state->fence_id = -1;
> > +	} else {
> > +		intel_parent_fb_pin_dpt_unpin(display, fb->dpt,
> > +					      old_plane_state->dpt_vma,
> > +					      old_plane_state->ggtt_vma);
> > +
> > +		old_plane_state->dpt_vma = NULL;
> > +		old_plane_state->ggtt_vma = NULL;
> > +	}
> > +}
> > +
> >  static int add_dma_resv_fences(struct dma_resv *resv,
> >  			       struct drm_plane_state *new_plane_state)
> >  {
> > diff --git a/drivers/gpu/drm/i915/display/intel_plane.h b/drivers/gpu/drm/i915/display/intel_plane.h
> > index 7b5456f56f42..a6338bba72d9 100644
> > --- a/drivers/gpu/drm/i915/display/intel_plane.h
> > +++ b/drivers/gpu/drm/i915/display/intel_plane.h
> > @@ -92,5 +92,8 @@ int intel_plane_atomic_check(struct intel_atomic_state *state);
> >  bool intel_plane_format_mod_supported_async(struct drm_plane *plane,
> >  					    u32 format,
> >  					    u64 modifier);
> > +int intel_plane_pin_fb(struct intel_plane_state *new_plane_state,
> > +		       const struct intel_plane_state *old_plane_state);
> > +void intel_plane_unpin_fb(struct intel_plane_state *old_plane_state);
> >  
> >  #endif /* __INTEL_PLANE_H__ */
> > diff --git a/drivers/gpu/drm/i915/i915_fb_pin.c b/drivers/gpu/drm/i915/i915_fb_pin.c
> > index cedefee46fbf..1034cb767e9f 100644
> > --- a/drivers/gpu/drm/i915/i915_fb_pin.c
> > +++ b/drivers/gpu/drm/i915/i915_fb_pin.c
> > @@ -3,20 +3,9 @@
> >   * Copyright © 2021 Intel Corporation
> >   */
> >  
> > -/**
> > - * DOC: display pinning helpers
> > - */
> > -
> >  #include <drm/drm_print.h>
> >  #include <drm/intel/display_parent_interface.h>
> >  
> > -#include "display/intel_display_core.h"
> > -#include "display/intel_display_types.h"
> > -#include "display/intel_fb.h"
> > -#include "display/intel_fb_pin.h"
> > -#include "display/intel_parent.h"
> > -#include "display/intel_plane.h"
> > -
> >  #include "gem/i915_gem_domain.h"
> >  #include "gem/i915_gem_object.h"
> >  
> > @@ -114,7 +103,7 @@ intel_fb_pin_to_dpt(struct drm_gem_object *_obj, struct intel_dpt *dpt,
> >  	return vma;
> >  }
> >  
> > -struct i915_vma *
> > +static struct i915_vma *
> >  intel_fb_pin_to_ggtt(struct drm_gem_object *_obj,
> >  		     const struct intel_fb_pin_params *pin_params,
> >  		     int *out_fence_id)
> > @@ -230,34 +219,6 @@ static void intel_fb_unpin_vma(struct i915_vma *vma, int fence_id)
> >  	i915_vma_put(vma);
> >  }
> >  
> > -static unsigned int
> > -intel_plane_fb_min_alignment(const struct intel_plane_state *plane_state)
> > -{
> > -	const struct intel_framebuffer *fb = to_intel_framebuffer(plane_state->hw.fb);
> > -
> > -	return fb->min_alignment;
> > -}
> > -
> > -static unsigned int
> > -intel_plane_fb_min_phys_alignment(const struct intel_plane_state *plane_state)
> > -{
> > -	struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
> > -	const struct drm_framebuffer *fb = plane_state->hw.fb;
> > -
> > -	if (!intel_plane_needs_physical(plane))
> > -		return 0;
> > -
> > -	return plane->min_alignment(plane, fb, 0);
> > -}
> > -
> > -static unsigned int
> > -intel_plane_fb_vtd_guard(const struct intel_plane_state *plane_state)
> > -{
> > -	return intel_fb_view_vtd_guard(plane_state->hw.fb,
> > -				       &plane_state->view,
> > -				       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,
> > @@ -336,81 +297,6 @@ static void i915_fb_pin_dpt_unpin(struct intel_dpt *dpt,
> >  		i915_dpt_unpin_from_ggtt(dpt);
> >  }
> >  
> > -int intel_plane_pin_fb(struct intel_plane_state *plane_state,
> > -		       const struct intel_plane_state *old_plane_state)
> > -{
> > -	struct intel_display *display = to_intel_display(plane_state);
> > -	struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
> > -	const struct intel_framebuffer *fb =
> > -		to_intel_framebuffer(plane_state->hw.fb);
> > -	struct i915_vma *ggtt_vma = NULL;
> > -	struct i915_vma *dpt_vma = NULL;
> > -	int fence_id = -1;
> > -	u32 offset;
> > -	int ret;
> > -
> > -	if (!intel_fb_uses_dpt(&fb->base)) {
> > -		struct intel_fb_pin_params pin_params = {
> > -			.view = &plane_state->view.gtt,
> > -			.alignment = intel_plane_fb_min_alignment(plane_state),
> > -			.phys_alignment = intel_plane_fb_min_phys_alignment(plane_state),
> > -			.vtd_guard = intel_plane_fb_vtd_guard(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),
> > -		};
> > -
> > -		ret = intel_parent_fb_pin_ggtt_pin(display, 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,
> > -			.alignment = intel_plane_fb_min_alignment(plane_state),
> > -			.needs_cpu_lmem_access = intel_fb_needs_cpu_access(&fb->base),
> > -		};
> > -
> > -		ret = intel_parent_fb_pin_dpt_pin(display, intel_fb_bo(&fb->base),
> > -						  fb->dpt, &pin_params,
> > -						  &dpt_vma, &ggtt_vma, &offset);
> > -		if (ret)
> > -			return ret;
> > -	}
> > -
> > -	plane_state->dpt_vma = dpt_vma;
> > -	plane_state->ggtt_vma = ggtt_vma;
> > -	plane_state->fence_id = fence_id;
> > -	plane_state->surf = offset + plane->surf_offset(plane_state);
> > -
> > -	return 0;
> > -}
> > -
> > -void intel_plane_unpin_fb(struct intel_plane_state *old_plane_state)
> > -{
> > -	struct intel_display *display = to_intel_display(old_plane_state);
> > -	const struct intel_framebuffer *fb =
> > -		to_intel_framebuffer(old_plane_state->hw.fb);
> > -
> > -	if (!intel_fb_uses_dpt(&fb->base)) {
> > -		intel_parent_fb_pin_ggtt_unpin(display,
> > -					       old_plane_state->ggtt_vma,
> > -					       old_plane_state->fence_id);
> > -
> > -		old_plane_state->ggtt_vma = NULL;
> > -		old_plane_state->fence_id = -1;
> > -	} else {
> > -		intel_parent_fb_pin_dpt_unpin(display, fb->dpt,
> > -					      old_plane_state->dpt_vma,
> > -					      old_plane_state->ggtt_vma);
> > -
> > -		old_plane_state->dpt_vma = NULL;
> > -		old_plane_state->ggtt_vma = NULL;
> > -	}
> > -}
> > -
> >  static void i915_fb_pin_get_map(struct i915_vma *vma, struct iosys_map *map)
> >  {
> >  	iosys_map_set_vaddr_iomem(map, i915_vma_get_iomap(vma));
> > diff --git a/drivers/gpu/drm/xe/display/xe_fb_pin.c b/drivers/gpu/drm/xe/display/xe_fb_pin.c
> > index c92c30ceba36..19f4d45f5acb 100644
> > --- a/drivers/gpu/drm/xe/display/xe_fb_pin.c
> > +++ b/drivers/gpu/drm/xe/display/xe_fb_pin.c
> > @@ -6,11 +6,12 @@
> >  #include <drm/intel/display_parent_interface.h>
> >  #include <drm/ttm/ttm_bo.h>
> >  
> > -#include "intel_display_core.h"
> > -#include "intel_display_types.h"
> > +/* FIXME move the types to parent interface? */
> > +#include "i915_gtt_view_types.h"
> > +
> > +/* FIXME move intel_remapped_info_size() & co. to parent interface? */
> >  #include "intel_fb.h"
> > -#include "intel_fb_pin.h"
> > -#include "intel_parent.h"
> > +
> >  #include "xe_bo.h"
> >  #include "xe_device.h"
> >  #include "xe_display_vma.h"
> > @@ -491,79 +492,6 @@ xe_fb_pin_reuse_vma(struct i915_vma *old_ggtt_vma,
> >  	return NULL;
> >  }
> >  
> > -int intel_plane_pin_fb(struct intel_plane_state *new_plane_state,
> > -		       const struct intel_plane_state *old_plane_state)
> > -{
> > -	struct intel_display *display = to_intel_display(new_plane_state);
> > -	const struct intel_framebuffer *fb = to_intel_framebuffer(new_plane_state->hw.fb);
> > -	const struct intel_framebuffer *old_fb = to_intel_framebuffer(old_plane_state->hw.fb);
> > -	struct drm_gem_object *obj = intel_fb_bo(&fb->base);
> > -	struct intel_plane *plane = to_intel_plane(new_plane_state->uapi.plane);
> > -	struct intel_fb_pin_params pin_params = {
> > -		.view = &new_plane_state->view.gtt,
> > -		.alignment = plane->min_alignment(plane, &fb->base, 0),
> 
> However xe had something different here.
> 
> Basically fb->min_alignment is initialized to intel_fb_min_alignment(),
> which does call plane->min_alignment() for all planes, and works it out
> from there.
> 
> Could or should we have switched xe to use fb->min_alignment here as an
> intermediate step? It kind of sticks out as a change in this patch.

I'm pretty sure there was a patch floating around for that.
Not sure why it didn't get pushed. Maybe just due to the general
apathy surrounding the xe fb code...

> 
> 
> > -		.needs_cpu_lmem_access = intel_fb_needs_cpu_access(&fb->base),
> > -	};
> > -	struct i915_vma *ggtt_vma = NULL;
> > -	struct i915_vma *dpt_vma = NULL;
> > -	int fence_id = -1;
> > -	u32 offset;
> > -	int ret;
> > -
> > -	ggtt_vma = intel_parent_fb_pin_reuse_vma(display,
> > -						 old_plane_state->ggtt_vma,
> > -						 intel_fb_bo(&old_fb->base),
> > -						 &old_plane_state->view.gtt,
> > -						 intel_fb_bo(&fb->base),
> > -						 &new_plane_state->view.gtt,
> > -						 &offset);
> > -	if (ggtt_vma)
> > -		goto got_vma;
> > -
> > -	if (!intel_fb_uses_dpt(&fb->base)) {
> > -		ret = intel_parent_fb_pin_ggtt_pin(display, obj, &pin_params,
> > -						   &ggtt_vma, &offset, NULL);
> > -		if (ret)
> > -			return ret;
> > -	} else {
> > -		ret = intel_parent_fb_pin_dpt_pin(display, obj, fb->dpt,
> > -						  &pin_params, &dpt_vma,
> > -						  &ggtt_vma, &offset);
> > -		if (ret)
> > -			return ret;
> > -	}
> > -
> > -got_vma:
> > -	new_plane_state->dpt_vma = dpt_vma;
> > -	new_plane_state->ggtt_vma = ggtt_vma;
> > -	new_plane_state->fence_id = fence_id;
> > -	new_plane_state->surf = offset + plane->surf_offset(new_plane_state);
> > -
> > -	return 0;
> > -}
> > -
> > -void intel_plane_unpin_fb(struct intel_plane_state *old_plane_state)
> > -{
> > -	struct intel_display *display = to_intel_display(old_plane_state);
> > -	const struct intel_framebuffer *fb = to_intel_framebuffer(old_plane_state->hw.fb);
> > -
> > -	if (!intel_fb_uses_dpt(&fb->base)) {
> > -		intel_parent_fb_pin_ggtt_unpin(display,
> > -					       old_plane_state->ggtt_vma,
> > -					       old_plane_state->fence_id);
> > -
> > -		old_plane_state->ggtt_vma = NULL;
> > -		old_plane_state->fence_id = -1;
> > -	} else {
> > -		intel_parent_fb_pin_dpt_unpin(display, fb->dpt,
> > -					      old_plane_state->dpt_vma,
> > -					      old_plane_state->ggtt_vma);
> > -
> > -		old_plane_state->dpt_vma = NULL;
> > -		old_plane_state->ggtt_vma = NULL;
> > -	}
> > -}
> > -
> >  static void xe_fb_pin_get_map(struct i915_vma *vma, struct iosys_map *map)
> >  {
> >  	*map = vma->bo->vmap;
> 
> -- 
> Jani Nikula, Intel

-- 
Ville Syrjälä
Intel