[PATCH v3 0/8] drm: replace simple display pipe users with atomic helpers

[Ze Huang <ze.huang@xxxxxxxxxxxxxxxx>]

struct drm_simple_display_pipe was meant to simplify simple DRM
drivers, but instead adds an extra wrapper around normal DRM atomic
helper setup. As noted in Documentation/gpu/todo.rst, remaining users
should be converted to regular atomic helpers and stop depending on the
simple-KMS interfaces.

This series converts the following drivers:

  - arcpgu
  - aspeed
  - mcde
  - pl111
  - gm12u320
  - repaper
  - tve200
  - xen frontend

Each patch replaces drm_simple_display_pipe_init() with explicit
primary plane, CRTC and encoder setup, and moves the old simple-pipe
callbacks into regular plane and CRTC helper callbacks named according
to local driver conventions.

The conversions preserve helper behavior that used to be implicit in
drm_simple_kms_helper.c, including plane-state validation, CRTC
primary-plane checks, affected-plane propagation, framebuffer prepare
handling, and existing event/vblank flow where applicable.

Result is less helper indirection and more explicit driver-side atomic
wiring, with no remaining simple-KMS dependency in these drivers.

Except for gm12u320, no hardware testing was performed.

This series is based on drm-next-2026-06-27.

AI usage disclosure:
- I wrote the first two commits myself. The remaining patches were completed
  with assistance from AI tools.
- AI tools were also used to review the code and suggest code changes for
  the DRM atomic conversion.

Thanks,
Ze Huang

Signed-off-by: Ze Huang <ze.huang@xxxxxxxxxxxxxxxx>
---
Changes in v3:
- Use atomic state from the commit path consistently in converted helpers:
  fetch new CRTC/plane state from the commit in enable/update/flush paths, and
  use drm_atomic_get_crtc_state() with PTR_ERR() handling in plane atomic_check
  hooks before drm_atomic_helper_check_plane_state().
- Move MCDE one-shot flow start from plane atomic_update() to CRTC
  atomic_flush(), after pending vblank event handling.
- Fix repaper damage update path to skip updates unless CRTC is active.
- Fix arcpgu missing remote encoder node handling and lock CRTC state access in
  debugfs.
- Make container helpers static inline.
- Link to v2: 
https://lore.kernel.org/r/20260716-drm-simple-kms-removal-v2-0-1133a8fc3785@xxxxxxxxxxxxxxxx

Changes in v2:
- common changes:
- create upcast helpers
- use 'commit' as name of struct drm_atomic_commit in atomic helpers
- improve control flow in *_crtc_helper_atomic_check() and
  *_plane_helper_atomic_check()
- Moved page-flip/vblank event handling out of plane update paths and into
  CRTC atomic_flush(), using atomic_flush and disable paths for mcde,
  pl111 and tve200
- arcpgu:
    - remove reduntant mod_supported helper
    - change obsolete mode field to crtc->state->mode
- mcde:
    - drop attach of unused encoder
- tve200:
    - reorder connector/bridge attach
- xen:
    - change possible_crtcs mask to 0
- Link to v1: 
https://patch.msgid.link/20260705-drm-simple-kms-removal-v1-0-b4e1ca053623@xxxxxxxxxxxxxxxx

---
Ze Huang (8):
      drm/arcpgu: replace struct drm_simple_display_pipe with regular atomic 
helpers
      drm/aspeed: replace struct drm_simple_display_pipe with regular atomic 
helpers
      drm/mcde: replace struct drm_simple_display_pipe with regular atomic 
helpers
      drm/pl111: replace struct drm_simple_display_pipe with regular atomic 
helpers
      drm/gm12u320: replace struct drm_simple_display_pipe with regular atomic 
helpers
      drm/repaper: replace struct drm_simple_display_pipe with regular atomic 
helpers
      drm/tve200: replace struct drm_simple_display_pipe with regular atomic 
helpers
      drm/xen: replace struct drm_simple_display_pipe with regular atomic 
helpers

 drivers/gpu/drm/aspeed/aspeed_gfx.h      |  11 +-
 drivers/gpu/drm/aspeed/aspeed_gfx_crtc.c | 203 ++++++++++++++++++-------
 drivers/gpu/drm/aspeed/aspeed_gfx_drv.c  |   3 +-
 drivers/gpu/drm/mcde/mcde_display.c      | 248 ++++++++++++++++++++-----------
 drivers/gpu/drm/mcde/mcde_drm.h          |  12 +-
 drivers/gpu/drm/mcde/mcde_drv.c          |   3 +-
 drivers/gpu/drm/pl111/pl111_display.c    | 199 ++++++++++++++++++-------
 drivers/gpu/drm/pl111/pl111_drm.h        |   5 +-
 drivers/gpu/drm/pl111/pl111_drv.c        |   3 +-
 drivers/gpu/drm/tiny/arcpgu.c            | 201 +++++++++++++++++++------
 drivers/gpu/drm/tiny/gm12u320.c          | 138 +++++++++++++----
 drivers/gpu/drm/tiny/repaper.c           | 138 +++++++++++++----
 drivers/gpu/drm/tve200/tve200_display.c  | 219 ++++++++++++++++++---------
 drivers/gpu/drm/tve200/tve200_drm.h      |   6 +-
 drivers/gpu/drm/tve200/tve200_drv.c      |  12 +-
 drivers/gpu/drm/xen/xen_drm_front.h      |   6 +-
 drivers/gpu/drm/xen/xen_drm_front_kms.c  | 188 ++++++++++++++++-------
 17 files changed, 1155 insertions(+), 440 deletions(-)
---
base-commit: 3696d07837d1df13a5603d77f667685e7dfb3c53
change-id: 20260704-drm-simple-kms-removal-01a031c6a129

Best regards,
-- 
Ze Huang <ze.huang@xxxxxxxxxxxxxxxx>