[Openchrome-devel] openchrome 0.6.0 regressions on VX900 laptop

[Xavier Bachelot]

Hi Kevin,

On 14/03/2017 04:42, Kevin Brace wrote:
> The register dump was helpful, and I think the cause of the FP not working is due to LVDS1 (The VIA datasheet calls it LVDS Channel 0 sometimes, but I will call it LVDS Channel 1. Accordingly, LVDS2 will be called LVDS Channel 2.) sending IGA1 display stream, not IGA2.
> When the computer boots, it probably sets LVDS1 display stream source to IGA1, and the register dump indicates this.
> If you manually switch the LVDS1 to IGA2, that should solve the bug.
> 
> $ cd tools
> $ sudo ./via_regs_dump -r 3d5.99
> 
> The screen according to your Version 0.6 + your panel index fix patch returned 0x01.
> Now, write 0x11 to 3X5.99
> 
> $ sudo ./via_regs_dump -w 3d5.99 11
> 
> Bit 4 of 3X5.99 determines the display source.
> 0 for IGA1 and 1 for IGA2.
> I hope this experiment will get the screen back.
> It appears that the LCDCK PLL is set correctly, so hopefully this fix will work.

That helps a bit, but does not fully fix the problem. A very distorted
image of what should be displayed is now showing in the upper half or
third of the FP. The remaining of the screen seems like uninitialized
memory.

Btw, via_regs_dump gets installed into /usr/sbin and also I'm here for
long enough to know how to build the driver and use the regs dumper, no
need to go into too much details. Actually, I did import the regs dumper
into the openchrome tree and even fixed a couple things in it.
For the record, the Epia M10K CLE266-based board that brought me to
Unichrome then Openchrome in 2004 just died, and I'm maintaining a
package for the driver for Fedora, unofficially then officially, since I
bought it. I still have a couple others VIA boards to play with (KM400A,
CN400, CN700, CX700, VX800, VX855 and VX900 based, some in a bad shape
though) possibly including another Epia M, I just need to find and
rescue it from a dusty shelf somewhere.

Regards,
Xavier