Re: [PATCHES] add _CST support

Len Brown
2004-12-22T20:37:32Z

I removed the D600 from the port replicator, and now
it is able to run in C4 w/o any hacks:

# cat /proc/acpi/processor/CPU0/power
active state: 2
max_cstate: C3
bus master activity: 02000001
states:
1: type[C1] promotion[2] demotion[-] latency[001]
usage[00111360]
*2: type[C2] promotion[3] demotion[1] latency[001]
usage[00085464]
3: type[C3] promotion[4] demotion[2] latency[085]
usage[00039905]
4: type[C3] promotion[-] demotion[2] latency[185]
usage[00453561]

So a list of things we need comes to mind:
Enable > C1 on SMP
max_cstate able to disable C4 w/o disabling C3
"nocst" flag to compare FADT method w/ _CST
bm_check code fix -- currently has no clue of HZ
a 100HZ kernel gets into C4 less than
a 1000HZ kernel, likely because of this.
tick-less idle loop

cheers,
-Len

ps.
I haven't been able to reproduce the rmmod processor failure,
though I did have a console log to show that I wasn't halucinating
at 2AM this morning:

[root@d600 root]# rmmod processor
ERROR: Module processor is in use by thermal
[root@d600 root]# rmmod thermal
[root@d600 root]# rmmod processor
ERROR: Module processor is in use
[root@d600 root]# lsmod
Module Size Used by
video 20548 0
processor 30504 2
fan 4228 0
container 4128 0
button 6608 0
battery 10852 0
ac 4740 0
[root@d600 root]# rmmod container
[root@d600 root]# rmmod processor
ERROR: Module processor is in use
[root@d600 root]# lsmod
Module Size Used by
video 20548 0
processor 30504 2
fan 4228 0
button 6608 0
battery 10852 0
ac 4740 0