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

Jani Nikula
2026-04-24T13:30:47Z

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.

> - .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