i.MX6 imx-drm framebuffer rotation. Kernel 3.14.52.

Commit Message

Philipp Zabel April 21, 2016, 1:16 p.m. UTC

Am Donnerstag, den 21.04.2016, 15:33 +0300 schrieb Ivan Nikolaenko:
> Hello all!
> 
> Mr. Fabio Estevam from freescale community forum advisedto address this 
> question to this mail list.
> 
> I am using a i.MX6Q SabreSD -based board with 3.14.52 kernel from Jethro 
> (2.0) release of FSL-Community-BSP.
> 
> I need to do a 180 degree vertical flip of the framebuffer using imx-drm 
> upon kernel initialization. But I can see that in the 
> ./drivers/video/mxc/mxc_ipuv3_fb.c file there are no support of rotation.
> Howisit meantto do?

No idea about the FSL kernel, but 180° rotation can't be done without
going through the IC, as far as I know. For a straight vertical flip
you'd just have to set the VF bit on the scanout IDMAC channel's CPMEM.
For example as a quick hack on v4.6-rc4:

-----8<-----
----->8-----

I suppose that could be hooked up to the KMS rotation property (reflect-y).

regards
Philipp

Comments

Ivan Nikolaenko April 22, 2016, 12:21 p.m. UTC | #1

Hi, Phillip!

Thank you for the fast responce.
Ifollowed your adviceandrealized thatIincorrectlyformulatedthought. I 
need a 180 degree rotation, not the flip.
I got the vertical flip (screen reflected by Y axis), butmy attempt to 
reflect it by X axis (xrandr --output DISP3\ BG --reflect x) failed 
(nothing happened).

Is there a way to do 180deg rotation somehow?


On 21.04.2016 16:16, Philipp Zabel wrote:
> to do a 180 degree vertical flip of the framebuffer using imx-drm
> >upon kernel initialization. But I can see th

Best regards, Ivan Nikolaenko.
[e-mail]

Philipp Zabel April 22, 2016, 12:49 p.m. UTC | #2

Am Freitag, den 22.04.2016, 15:21 +0300 schrieb Ivan Nikolaenko:
> Hi, Phillip!
> 
> Thank you for the fast responce.
> Ifollowed your adviceandrealized thatIincorrectlyformulatedthought. I 
> need a 180 degree rotation, not the flip.
> I got the vertical flip (screen reflected by Y axis), butmy attempt to 
> reflect it by X axis (xrandr --output DISP3\ BG --reflect x) failed 
> (nothing happened).

That is because the IDMAC controller considers the VF bit when
calculating the line start addresses (so reflect Y works) but completely
ignores the HF bit. The IC has a line buffer that is sampled backwards
if the HF bit is set.

> Is there a way to do 180deg rotation somehow?

If your display is < 1024 pixels in both width and height, it should be
possible to get reflect x functionality by hooking up the IC -> DMFC
direct flow.

regards
Philipp

Patch

diff --git a/drivers/gpu/drm/imx/ipuv3-plane.c b/drivers/gpu/drm/imx/ipuv3-plane.c
index 681ec6e..37d9ebd 100644
--- a/drivers/gpu/drm/imx/ipuv3-plane.c
+++ b/drivers/gpu/drm/imx/ipuv3-plane.c
@@ -291,6 +291,7 @@  int ipu_plane_mode_set(struct ipu_plane *ipu_plane, struct drm_crtc *crtc,
 	ipu_dmfc_config_wait4eot(ipu_plane->dmfc, crtc_w);
 
 	ipu_cpmem_zero(ipu_plane->ipu_ch);
+	ipu_cpmem_set_rotation(ipu_plane->ipu_ch, IPU_ROTATE_VERT_FLIP);
 	ipu_cpmem_set_resolution(ipu_plane->ipu_ch, src_w, src_h);
 	ret = ipu_cpmem_set_fmt(ipu_plane->ipu_ch, fb->pixel_format);
 	if (ret < 0) {