[PATCH v3 00/12] drm/fbdev: Remove DRM's helpers for fbdev I/O

Thomas Zimmermann tzimmermann at suse.de
Mon May 22 05:21:28 PDT 2023


DRM provides a number of wrappers around fbdev cfb_() sys_(), fb_io_()
and fb_sys_() helpers. The DRM functions don't provide any additional
functionality for most DRM drivers. So remove them and call the fbdev
I/O helpers directly.

The DRM fbdev I/O wrappers were originally added because <linux/fb.h>
does not protect its content with CONFIG_FB. DRM fbdev emulation did
not build if the config option had been disabled. This has been
fixed. For fbdev-generic and i915, the wrappers added support for damage
handling. But this is better handled within the two callers, as each
is special in its damage handling.

Patch 1 adds several internal Kconfig otpions that DRM drivers (and
possibly other fbdev code) will use to select the correct set of I/O
helpers.

Patches 2 to 9 replace the DRM wrappers in a number of fbdev emulations.
Patch 10 exports two helpers for damage handling. Patches 11 and 12
update fbdev-generic and i915 with the help of the exported functions.
The patches also remove DRM's fbdev I/O helpers, which are now unused.

DRM's fbdev helpers had to select fbdev I/O helpers for I/O and for
system memory. Each fbdev emulation now selects the correct helpers
for itself. Depending on the selected DRM drivers, kernel builds will
now only contain the necessary fbdev I/O helpers and might be slightly
smaller in size.

v3:
	* fix Kconfig options (Jingfeng)
	* minimize changes to exynos (Sam)
v2:
	* simplify Kconfig handling (Sam)

Thomas Zimmermann (12):
  fbdev: Add Kconfig options to select different fb_ops helpers
  drm/armada: Use regular fbdev I/O helpers
  drm/exynos: Use regular fbdev I/O helpers
  drm/gma500: Use regular fbdev I/O helpers
  drm/radeon: Use regular fbdev I/O helpers
  drm/fbdev-dma: Use regular fbdev I/O helpers
  drm/msm: Use regular fbdev I/O helpers
  drm/omapdrm: Use regular fbdev I/O helpers
  drm/tegra: Use regular fbdev I/O helpers
  drm/fb-helper: Export helpers for marking damage areas
  drm/fbdev-generic: Implement dedicated fbdev I/O helpers
  drm/i915: Implement dedicated fbdev I/O helpers

 drivers/gpu/drm/Kconfig                    |  10 +-
 drivers/gpu/drm/armada/Kconfig             |   1 +
 drivers/gpu/drm/armada/armada_fbdev.c      |   9 +-
 drivers/gpu/drm/drm_fb_helper.c            | 233 ++-------------------
 drivers/gpu/drm/drm_fbdev_dma.c            |  12 +-
 drivers/gpu/drm/drm_fbdev_generic.c        |  47 ++++-
 drivers/gpu/drm/exynos/Kconfig             |   1 +
 drivers/gpu/drm/exynos/exynos_drm_fbdev.c  |  10 +-
 drivers/gpu/drm/gma500/Kconfig             |   1 +
 drivers/gpu/drm/gma500/fbdev.c             |   9 +-
 drivers/gpu/drm/i915/Kconfig               |   1 +
 drivers/gpu/drm/i915/display/intel_fbdev.c |  51 ++++-
 drivers/gpu/drm/msm/Kconfig                |   1 +
 drivers/gpu/drm/msm/msm_fbdev.c            |  12 +-
 drivers/gpu/drm/omapdrm/Kconfig            |   1 +
 drivers/gpu/drm/omapdrm/omap_fbdev.c       |  12 +-
 drivers/gpu/drm/radeon/Kconfig             |   1 +
 drivers/gpu/drm/radeon/radeon_fbdev.c      |   9 +-
 drivers/gpu/drm/tegra/Kconfig              |   1 +
 drivers/gpu/drm/tegra/fbdev.c              |  11 +-
 drivers/video/fbdev/Kconfig                |  21 ++
 include/drm/drm_fb_helper.h                |  84 +-------
 22 files changed, 183 insertions(+), 355 deletions(-)


base-commit: f533234d40e8f5b8599bd5bc97fa8e30384aec03
prerequisite-patch-id: 0aa359f6144c4015c140c8a6750be19099c676fb
prerequisite-patch-id: c67e5d886a47b7d0266d81100837557fda34cb24
prerequisite-patch-id: cbc453ee02fae02af22fbfdce56ab732c7a88c36
-- 
2.40.1




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