On 15-12-07 09:08, Paul Rolland wrote:
> Hello,
> 
> On Fri, 14 Dec 2007 23:29:55 +0000
> Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> 
>> On Fri, 14 Dec 2007 14:13:46 -0800
>> "H. Peter Anvin" <hpa@zytor.com> wrote:
>>
>>> Pavel Machek wrote:
>>>> On Fri 2007-12-14 10:02:57, H. Peter Anvin wrote:
>>> How long will that take to boot on a 386?
>> Well the dumb approach to fix that would seem to be to initialise it to
>>
>> 	cpu->family   3 -> 50MHz 4 -> 300Mhz 5-> etc...
> 
> Just an idea : from what I've read, the problem (port 80 hanging) only occurs
> on 'modern' machines... So why not :
>  - use port 80 for old CPUs (PII, PIII) where it has never really been
>    a problem,
>  - use the cpu->family to do a best match for CPU freq
> thus we could avoid increasing boot time too much...

Yes, just posted a Patch-For-Comments that switches on the availability of a 
TSC (tsc_init sets tsc_disable also for !cpu_has_tsc) which would mean that 
only really old stuff would be using the outb still. A TSC is really all we 
need to have a sensible udelay().

Rene.