[PATCH 0/2] drm: CMA fbdev stride adjustment

Rob Herring robh at kernel.org
Wed Aug 12 13:52:12 PDT 2015

I'm working on a DRM driver for PXA1928. Other than a stride alignment 
requirement of 16 bytes, I have no other reason not to use fbdev_cma. 
While I can adjust the stride for drm_gem_cma_dumb_create, I cannot do 
the same for drm_fbdev_cma_create without duplicating a bunch of code. 
This series allows fbdev_cma users to override the fb_probe function, so 
the stride can be adjusted.

It appears to me that rcar-du has a bug that it doesn't handle alignment 
requirements for this case as well. Probably just getting lucky with 
tested resolutions/bpp.

Also, AFAICT the Rockchip driver has no real reason to use a custom GEM 
allocator instead of the CMA one. It sets the DMA_ATTR_NO_KERNEL_MAPPING 
DMA attr, but that could easily be supported by the CMA allocator.


Rob Herring (2):
  drm/cma: allow custom fb helper functions
  drm/cma: allow adjusting the pitch for CMA fbdev

 drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c |  2 +-
 drivers/gpu/drm/drm_fb_cma_helper.c          | 13 ++++++++++---
 drivers/gpu/drm/imx/imx-drm-core.c           |  2 +-
 drivers/gpu/drm/rcar-du/rcar_du_kms.c        |  3 ++-
 drivers/gpu/drm/sti/sti_drm_drv.c            |  2 +-
 drivers/gpu/drm/tilcdc/tilcdc_drv.c          |  2 +-
 include/drm/drm_fb_cma_helper.h              |  7 +++++++
 include/drm/drm_fb_helper.h                  |  1 +
 8 files changed, 24 insertions(+), 8 deletions(-)


More information about the dri-devel mailing list