G5 fan problems return moving to 2.6.15 with dual processor 2.7GHz machine

[Benjamin Herrenschmidt]

On Wed, 2006-02-08 at 22:02 -0800, Brian D. Carlstrom wrote:
> Benjamin Herrenschmidt writes:
>  > prom_printf should work ... try booting manually (from the OF command
>  > line) and maybe comment out the code that opens the displays... (it
>  > may be clearing the screen)....
> 
> I tried commented out prom_check_displays and that does prevent the
> clearing of the screen, but still no visible prom_printf output. The
> last output seems to be from yaboot, its certainly not one of the
> prom_print messages from prom_init.c. For good measure, I also tried
> adding "video=ofonly". Still no prom_printf output visible.
> 
> However, when I rebooted back to my 2.6.14 kernel, I saw the usual
> prom_printf messages from prom_init without any changes. I reviewed the
> prom_init.c diffs between 2.6.14 and 2.6.15 but they are large enough
> that its not easy to spot an obvious problem.
> 
> In any case, I didn't have much time to really look at this today, just
> enough to try the disabling prom_check_displays, I'll have to look more
> Friday.

That is strange... 

Ben.