confused about HID1 bits and G5

Greg Watson gwatson at
Fri Apr 30 09:16:35 EST 2004

On 29/04/2004, at 3:49 PM, Benjamin Herrenschmidt wrote:

> On Fri, 2004-04-30 at 01:05, Greg Watson wrote:
>> As a firmware designed (LinuxBIOS), I would support this. Obviously
>> there are some things that the firmware has to do, like enable memory,
>> but the less reliance the o/s has on magic behavior the better. It
>> makes firmware design simpler and more reliable.
> There is nothing like "magic behaviour" here. There is a set of
> features that should normally be enabled on the CPU, this set is
> clearly defined in the spec, the firmware should enabled them.
> As I wrote, I prefer not touching most of this from the kernel since
> some specific CPU rev. errata may involve disabling some of those,
> and that is typically done by the firmware, at least on pmacs. Now,
> it's possible that I decide to force more of these bits myself based
> on experience with broken firmwares, but so far, this has not been
> necessary :)

Well the good thing about LinuxBIOS is you can fix the firmware. :-)


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