powernow regression in 8-STABLE

Jeremy Chadwick freebsd at jdc.parodius.com
Thu Jul 21 21:43:13 UTC 2011

On Fri, Jul 22, 2011 at 06:56:00AM +1000, Callum Gibson wrote:
> On 21Jul11 12:07, Jung-uk Kim wrote:
> }Can you please do "set debug.cpufreq.verbose=1" from loader prompt and 
> }show me the dmesg output?  I want to see intial settings.  You can 
> }reset it from command line with "sysctl debug.cpufreq.verbose=0" 
> }later.
> http://members.optusnet.com.au/callumgibson/boot_verboser.out
> Also, as suggested by jhb@, with legacy usb disabled:
> http://members.optusnet.com.au/callumgibson/boot_verboser_nousb.out
> and dev.cpu.0.freq reappears! Spooky. Is that a solution or a workaround?
> I noticed this disables usb keyboard support at the boot menus.

"Legacy USB" support is a horribly-named BIOS option.

What the option actually does, without getting into the technicalities,
is make your USB keyboard work inside of environments where there is no
USB driver.  The most commonly-used examples are bootloader/bootstraps
and MS-DOS.

The BIOS itself (meaning the firmware/BIOS, not "the BIOS as in a piece
of legacy technology") has a tiny USB stack in it.  That's how your
USB keyboard is able to work (e.g. to press Del or F2 to get into the
BIOS itself), and how you're able to boot from USB-attached devices.

You should keep "Legacy USB" enabled if you want your keyboard to work
in bootloaders/bootstraps.  If enabling this feature breaks something
else, that sounds like a bug in the vendor BIOS to me, and you should
contact the vendor or motherboard manufacturer to inform them of the

| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                   Mountain View, CA, US |
| Making life hard for others since 1977.               PGP 4BD6C0CB |

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