Hello, Andy,
On 7/3/2012 2:14 AM, Andy Green wrote:
On 07/03/12 03:47, the mail apparently from David Cullen included:
After running some experiments here, I discovered that the Linaro Ubuntu images only work with displays that have a native resolution of 1920x1080.
I tried to use kernel command line arguments to force the resolution to work with my 1680x1050 monitor, but my changes had no effect. I wanted to look at the kernel source for the Linaro Ubuntu image because I can probably figure out the correct kernel command line arguments from that. However, I could not figure out which git tree to use.
Just to be clear, the kernel is recognizing your monitor and coming up with kms OK at your native resolution?
What's "kms"? But yes, the kernel appears to be driving the monitor at the native resolution.
IIUI Xorg starts and you get a pointer you can move around but Xorg chokes somewhere.
If Xorg choked, would I even have a mouse pointer?
Did you have a look at the Xorg logs then, or try to come up in runlevel three and do startx at the terminal?
No. I'm not an expert at troubleshooting Xorg problems, so I didn't even think about doing any of that. I'll give it a shot and post my findings.
If I did get the idea I am not sure recooking the kernel will change much, it's actually doing its side (as distinct from SGX module perhaps) okay from the sound of it.
After looking at the kernel source for another project, I was able to figure out how to pass LCD panel timings via the kernel command line to get the resolution I needed. So one reason I wanted to look at the Linaro kernel source was to try to figure out how to force the DVI output to use a specific resolution and bit depth.
However, the image from here
http://cdimage.ubuntu.com/releases/12.04/release/ubuntu-12.04-preinstalled-d...
does display the GUI properly on my monitor, so I know it can be done. This raises the question, "What are the differences between the Ubuntu image and the Linaro image?" If the primary difference is the kernel, then rebuilding the kernel may fix the problem.
However, the real reason I need to rebuild the kernel has nothing to do with getting the GUI working. Unfortunately, it is not obvious to me how to acquire the source to the kernel that goes with the image here
http://releases.linaro.org/12.06/ubuntu/leb-panda/
Using apt, I can easily get the source for the Ubuntu image mentioned above. So, I will be sticking with the Ubuntu image for now.