Hi,
just to let you know (any i the hope that somebody has a good comment).

It is still not working although all ssd2858 registers (except one status register) have the same value.

The only diffs I can find are:

91c91
< 608c: 00 00 03 c2
---
> 608c: 00 00 03 ca

And allmost all DSI/DISPC registers I can read from debugfs have the same value.

The only diffs are:

40c40
< DISPC_LINE_STATUS                                  000000fa
---
> DISPC_LINE_STATUS                                  000000d0
103,104c103,104
< DISPC_OVL_BA0(VID1)                                7f77c000
< DISPC_OVL_BA1(VID1)                                7f77c000
---
> DISPC_OVL_BA0(VID1)                                7f6dc000
> DISPC_OVL_BA1(VID1)                                7f6dc000

Line status must be different because it is the line counter which depends on where the "electron beam"
is when the register is read.

I don't exactly know which registers DISPC_OVL_BA0 are and what they do but, I have digged through
the source code and found out that the reason is a different framebuffer base address in omap_plane_atomic_update().
So it is just a side-effect of loading the driver in a different sequence compared to others. And should not be
the reason for our symptoms.

The symptoms are:
* with mipi-debug driver and ssd2858 script it works in normal or rotation mode (this is how ED presents the Pyra to the public)
* it does not work (although it did last week) in ssd test pattern output mode.
* with ssd2858.ko it shows a b/w striped pattern (which does not depend on video input) - but the pattern rotates if the ssd2858 is instructed to do so


* it does also not work in ssd test pattern output mode
* I can see with oscilloscope on the ssd MIPI input lanes that there is a video input from the OMAP which also depends on the X11 image (e.g. start/stop iceweasel adds/removes a window and changes the signals)


* in ssd test mode I can see that the pattern changes every second which is what I expect (it should loop slowly through rgb colors)
* the output signals differ between mipi-debug + ssd script and ssd2858.ko - although the ssd registers have the same values

 

What is most interesting is that with the ssd2858.ko the video output is running a little faster - although this is not
obviously instructed by input signals or different register settings.

I think we have to ask the manufacturer of the ssd2858 if the chip has hidden registers...

BR,
Nikolaus