monline

I've spent quite some time now debugging the issue and finally got it working.

Here's what to do:

1. Configure the kernel to have "Support for frame buffer devices", "AMD Geode GX1 framebuffer" and "Framebuffer console support" compiled in (see section "Device Drivers / Graphics support" in kernel config). These three should be part of the kernel, putting them into modules is not sufficient. No other framebuffer driver should be in the kernel except for the Geode GX1 driver.
2. In the kernel loader specify the video=gx1fb:mode:1024x768-16@75 and the vga=0x317 parameters. The point is that both must be specified. If you add only one of them, then you'll see some artifacts/bugs on screen.

The first parameter stands for mode:<x-resolution>x<y-resolution>-<bit-depth>@<horizontal-refresh-frequency>. The second parameter is a VESA mode number. You can check out the possible values of the vga parameter here. The video and vga params must be in sync.