

modesetting feature status


So one of the features we've been trying to land for F10 that is a major
change in how we deal with graphics hardware in the Linux world. 


This is going to be a slightly bumpy ride as it involves re-doing all we
know about GPU drivers from the ground up. From the kernel to X.org to
3D pieces.

So first off how to disable modesetting: 

add nommodeset to the kernel command line in grub
grub can be accessed by holding down the Ctrl key.

We are targeting for F10 support for radeon GPUs from r300 to r500 (and
possibly r600/r700), and Intel GPUs from i830 to GM45 (though it may end
up i915 and up only)

For the beta we are only going to enable Radeon support for the r300 to
r500 class of hardware, while we await upstream changes to the Intel
driver. The intel mode code is more mature, however Intel are currently
trying to push the memory manager feature to the kernel first, so are
working on stabilising that before finishing the mode setting code. We
are including the current Intel code but not enabling it at all until
further work is completed. We will switch the code on depending on how
things play out and how much testing we think it has had.

So why are we doing this:

1. Way better startup sequence.
2. Faster X startup.
3. Better fast-user-switching support
4. Better suspend/resume support
5. Oops/panic messages can appear when X is running.

Caveats for Beta release:

1. Performance
You will probably notice performance is below what you are used to on
the same hardware with the older drivers. This is due to a lack of
performance optimization so far and also now that we do more stuff in
the kernel, the kernel debugging overheads have a lot more influence on
the desktop.

2. 3D.
3D support is not as good. We are currently working with a beta 3D
driver on these cards. Compiz might not work for the beta release, we
will get it working for F10 final of course.

3. suspend/resume.
Suspend/resume may corrupt the graphics.

Thanks to everyone who has been involved in this so far and testing all
that they have so far.

