Kernel almost hangs when CONFIG_DRM_RADEON=y

[Peter Zijlstra]

On Sun, 2011-08-28 at 07:36 +0200, Borislav Petkov wrote:
> > > With CONFIG_DRM_RADEON=y, the microcode is needed before it can be
> > > loaded from userspace, so it needs to be built into the kernel as well.
> > 
> > How should I do that? I've tried to set all "m"s to "y" in .config and
> > still saw this issue. Should I set some special parameter?
> 
> You need to add "radeon/CEDAR_pfp.bin" to CONFIG_EXTRA_FIRMWARE when you
> configure your kernel and enable CONFIG_FIRMWARE_IN_KERNEL.
> 
> The radeon/CEDAR_pfp.bin file (+ leading directory, mind you) should
> most probably be located in /lib/firmware or to whatever you have set
> CONFIG_EXTRA_FIRMWARE_DIR so that Kbuild can find it (if not, you'll get
> a warning at the end of the kernel build). This way, it works for both
> radeon being =m and =y.

Should we make Kconfig pop up a dialog and ask for the whereabouts of
these firmware thingies when you mark the driver =y? 

This all sounds like magic to me, having to know you need to add to
EXTRA_FIRMWARE, having to know what file it needs etc.. For all intents
and purposes =y just doesn't work and that's broken.