Console options for legacy-free mini-itx server?

[Ian Smith]

On Fri, 19 Nov 2010, John Baldwin wrote:
 > On Thursday, November 18, 2010 10:14:44 pm Ian Smith wrote:
 > > On Thu, 18 Nov 2010, John Baldwin wrote:
 > >  > On Thursday, November 18, 2010 4:07:27 pm Andrew Reilly wrote:
 > >  > > Hi John,
 > >  > > 
 > >  > > On 18/11/2010, at 23:59 , John Baldwin wrote:
 > >  > > 
 > >  > > > You used devinfo -v, so it shows the devices that exist even if they failed
 > >  > > > to attach.  Try just using 'devinfo' and seeing if est1 still shows up.
 > >  > > 
 > >  > > OK, you're right: running without -v shows only est0:
 > >  > > 
 > >  > > nexus0
 > >  > >   apic0
 > >  > >   ram0
 > >  > >   acpi0
 > >  > >     cpu0
 > >  > >       acpi_perf0
 > >            ^^^^^^^^^^
 > >  > >       est0
 > >  > >       p4tcc0
 > >  > >       cpufreq0
 > >  > >     cpu1
 > >  > >       p4tcc1
 > >  > >       cpufreq1
 > >  > >     acpi_button0
 > >  > >     pcib0
 > >  > > <...>
 > >  > > 
 > >  > > Is est. involved in the reboot question?
 > >  > 
 > >  > Probably not.
 > > 
 > > I'm not so sure, having just noticed something that I missed last time:
 > 
 > Not being able to alter the speed of CPU 1 shouldn't impact the ability to
 > reboot the system.

I guess not, unless the BIOS bug Andriy postulated may affect that too.

 > > device_attach: acpi_perf1 attach returned 6
 > > est0: <Enhanced SpeedStep Frequency Control> on cpu0
 > > p4tcc0: <CPU Frequency Thermal Control> on cpu0
 > > device_attach: acpi_perf1 attach returned 6
 > > est1: <Enhanced SpeedStep Frequency Control> on cpu1
 > > est: CPU supports Enhanced Speedstep, but is not recognized.
 > > est: cpu_vendor GenuineIntel, msr 16
 > > device_attach: est1 attach returned 6
 > > p4tcc1: <CPU Frequency Thermal Control> on cpu1
 > > 
 > > I'd mis-read or assumed that first line as being for acpi_perf0, rather 
 > > than an earlier? attempt to attach acpi_perf1 at that time.
 > > 
 > > From cpufreq(4):
 > > 
 > >      The following device drivers offer absolute frequency control via the
 > >      cpufreq interface.  Usually, only one of these can be active at a time.
 > > 
 > >      acpi_perf  ACPI CPU performance states
 > >      est        Intel Enhanced SpeedStep
 > >      ichss      Intel SpeedStep for ICH
 > >      powernow   AMD PowerNow! for K7 and K8
 > >      smist      Intel SMI-based SpeedStep for PIIX4
 > > 
 > > Apart from never having seen est0 attach but est1 not, my understanding 
 > > from both the manual and from having read some of the code over the time 
 > > is that acpi_perf0 should only attach if eg est0 didn't - is that wrong?
 > > 
 > > Note also that there's no mention of acpi_perf0 attaching in the dmesg, 
 > > where I'm used to seeing that listed (eg as with my P3-Mobile CPU)
 > 
 > acpi_perf(4) operates in two modes.  One is that it actively manages the CPU,
 > the second is that it provides the data table that other drives like est(4)
 > use.  In the second mode it marks itself as quiet so it does not show up in
 > dmesg.

Ah, thanks for that.  Way past time I had another browse through all 
this.  Thanks also to Andriy for his explanation.

[ BTW, there's never been an acpi_perf(4), nor manuals for the other 
cpufreq drivers listed above, nor relatives acpi_throttle and p4tcc, 
which I took as encouragement to study some of that code back then.

That is, unless they've been added since 8-stable, not impossible as 
four new manpages mav@ added to head over a month ago - eventtimers(7), 
attimer(4), atrtc(4), hpet(4) - still haven't turned up yet at eg: 
http://www.freebsd.org/cgi/man.cgi?query=hpet&apropos=0&sektion=0&manpath=FreeBSD+9-current&format=html

I mentioned this to simon@, no news so far; anyone else I should ping? ]

cheers, Ian