[PATCH v4 00/11] Enabling 180 degree rotation for sprite and crtc planes

[One Thousand Gnomes]

> > Does this mean it should also handle horizontal mirroring in
> > hardware (180° rotate, and scan lines backwards combined) ?
> 
> Our hardware doesn't support mirroring (h or v). Well, unless you
> count h+v mirroring since that's 180 degree rotation :)
> 
> Anyways IIRC the old video overlay (present on gen2-4) was the only plane
> to ever support mirroring on Intel hardware. With all other planes we're
> limited to 0 and 180 degree rotation

It seems to do vertical mirroring providing your output buffer is
allocated and aligned on page boundaries as the GTT can then be used to
map the scan lines in any order you like ?

Alan