[PATCH 06/16] drm/omap: remove dma & vrfb rotation

[Laurent Pinchart]

Hi Tomi,

Thank you for the patch.

On Thursday 04 May 2017 13:23:22 Tomi Valkeinen wrote:
> We have three rotation methods supported by the SoCs with DSS: DMA,
> VRFB and TILER.
> 
> DMA rotation works in theory on all DSS platforms, but in practice it's
> unusable due to the huge amount of memory bandwidth it uses, and has
> never really been used.
> 
> VRFB is available on OMAP3, but is not supported by omapdrm, even though
> we have some code for it in the dispc driver.
> 
> TILER is supported on OMAP4/OMAP5/DRA7/AM5 platforms, but has some
> driver bugs.
> 
> To clean up the driver to help fixing the TILER issues, this patch drops
> the DMA and VRFB rotation support, leaving only TILER rotation.

I'm fine dropping DMA rotation, but I have mixed feelings about VRFB. Yes, it 
doesn't work at the moment, but I know users of VRFB with the omap_vout driver 
who would really like to switch to omapdrm. Porting VRFB from omap_vout to 
omapdrm has been on my to-do list for a long time (with a low priority 
unfortunately). As an added bonus, it would allow dropping the omap_vout 
driver at some point.

What would you think about dropping DMA but keeping VRFB for now ?

> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
> ---
>  drivers/gpu/drm/omapdrm/dss/dispc.c        | 248 --------------------------
>  drivers/gpu/drm/omapdrm/dss/dss_features.c |  16 --
>  drivers/gpu/drm/omapdrm/dss/dss_features.h |   2 -
>  drivers/gpu/drm/omapdrm/dss/omapdss.h      |   5 +-
>  drivers/gpu/drm/omapdrm/omap_fb.c          |   2 +-
>  drivers/gpu/drm/omapdrm/omap_plane.c       |   2 +-
>  6 files changed, 10 insertions(+), 265 deletions(-)

-- 
Regards,

Laurent Pinchart