No speedstep support for Atom N450 ?

[Joel Carnat <joel%carnat.net@localhost>]

Hello,

I ran NetBSD 5.99.34 on my Dell Inspiron Mini 1012 and it seems the 
speedstep feature of the shipped Atom N450 is not working.

Here's the full "machdep" section from sysctl:
machdep.biosbasemem = 631
machdep.biosextmem = 2085632
machdep.booted_kernel = netbsd
machdep.diskinfo: 80:31326208(925/255/63),2 81:488397168(1023/255/63),2 
 wd0:81
sd0:80 sd1
machdep.fpu_present = 1
machdep.osfxsr = 1
machdep.sse = 1
machdep.sse2 = 1
machdep.sleep_state = 0
machdep.acpiapm.standby = 1
machdep.acpiapm.suspend = 3
machdep.acpi_vbios_reset = 1
machdep.acpi_beep_on_reset = 0
machdep.cpu_brand = Intel(R) Atom(TM) CPU N450   @ 1.66GHz
machdep.sparse_dump = 1
machdep.tsc_freq = 1662580200
machdep.idle-mechanism = mwait

`cpuctl` says:
Num  HwId Unbound LWPs Interrupts Last change              #Intr
---- ---- ------------ ---------- ------------------------ -----
0    0    online       intr       Wed Jul  7 23:36:21 2010 12
1    1    online       intr       Wed Jul  7 23:36:21 2010 0
cpu0: Intel Atom (686-class), 1662.58 MHz, id 0x106ca
cpu0: features  0xbfe9fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR>
cpu0: features  0xbfe9fbff<PGE,MCA,CMOV,PAT,CFLUSH,DS,ACPI,MMX,FXSR,SSE>
cpu0: features  0xbfe9fbff<SSE2,SS,HTT,TM,SBF>
cpu0: features2 0x40e39d<SSE3,DTES64,MONITOR,DS-CPL,EST,TM2,SSSE3,CX16,xTPR>
cpu0: features2 0x40e39d<PDCM,MOVBE>
cpu0: features3 0x20100000<XD,EM64T>
cpu0: features4 0x1<LAHF>
cpu0: "Intel(R) Atom(TM) CPU N450   @ 1.66GHz"
cpu0: I-cache 32KB 64B/line 8-way
cpu0: Initial APIC ID 0
cpu0: Cluster/Package ID 0
cpu0: SMT ID 0
cpu0: family 06 model 0c extfamily 00 extmodel 01

OpenBSD 4.7 can manage the speed (from 1.6GHz to 1.0GHz) ; or at least 
it claims to ;-) Here's relevant informations from dmesg:
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: apic clock running at 166MHz
cpu1 at mainbus0: apid 1 (application processor)
cpu1: Intel(R) Atom(TM) CPU N450 @ 1.66GHz ("GenuineIntel" 686-class) 
1.67 GHz
cpu1: 
FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,CFLUSH,D
S,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,SBF,SSE3,MWAIT,DS-CPL,EST,TM2,CX16,xTPR
cpu0: Enhanced SpeedStep 1663 MHz: speeds: 1667, 1333, 1000 MHz

and its "hw" section from sysctl:
hw.machine=i386
hw.model=Intel(R) Atom(TM) CPU N450 @ 1.66GHz ("GenuineIntel" 686-class)
hw.ncpu=2
hw.byteorder=1234
hw.pagesize=4096
hw.disknames=sd0,sd1,sd2
hw.diskcount=3
hw.sensors.acpiac0.indicator0=Off (power supply)
hw.sensors.acpibat0.volt0=11.10 VDC (voltage)
hw.sensors.acpibat0.volt1=11.04 VDC (current voltage)
hw.sensors.acpibat0.watthour0=56.34 Wh (last full capacity)
hw.sensors.acpibat0.watthour1=5.63 Wh (warning capacity)
hw.sensors.acpibat0.watthour2=1.69 Wh (low capacity)
hw.sensors.acpibat0.watthour3=22.49 Wh (remaining capacity), OK
hw.sensors.acpibat0.raw0=1 (battery discharging), OK
hw.sensors.acpibat0.raw1=13298 (rate)
hw.sensors.cpu0.temp0=40.00 degC
hw.cpuspeed=1000
hw.setperf=0
hw.vendor=Dell Inc.
hw.product=Inspiron 1012
hw.version=A04
hw.serialno=8C6V4L1
hw.uuid=44454c4c-4300-1036-8056-b8c04f344c31
hw.physmem=2136297472
hw.usermem=2136219648
hw.ncpufound=2

Did I miss something ?

TIA,
        Jo