drm/omapdrm: dispc: Refuse x-decimation above 4 for all but 8-bit formats
authorJyri Sarha <jsarha@ti.com>
Wed, 8 Feb 2017 14:08:06 +0000 (16:08 +0200)
committerTomi Valkeinen <tomi.valkeinen@ti.com>
Thu, 16 Feb 2017 12:11:08 +0000 (14:11 +0200)
commit1b30ab0c40a99da347c1ab83c30b485e03fe9f64
treebd084ce1b08ce56cd1d70b90108e5e8cbeb56c93
parent897145d0c7010b4e07fa9bc674b1dfb9a2c6fff9
drm/omapdrm: dispc: Refuse x-decimation above 4 for all but 8-bit formats

Let's disable all scaling that requires horizontal decimation with
higher factor than 4, until we have better estimates of what we can
and can not do. However, NV12 color format appears to work Ok with
all decimation factors.

When decimating horizontally by more that 4 the dss is not able to
fetch the data in burst mode. When this happens it is hard to tell if
there enough bandwidth. Despite what theory says this appears to be
true also for 16-bit color formats.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
drivers/gpu/drm/omapdrm/dss/dispc.c