AMD A12-8800B ACPI questions (turbo mode, temp zones)

[Ian Smith]

On Sun, 13 Dec 2015 19:53:52 -0500, Johannes Dieterich wrote:
 > Dear list,
 > 
 > I am running CURRENT on an HP elitebook 745 G3 which comes with a AMD
 > A12-8800B CPU. All in all, it runs very well with just a few nits to
 > pick. Two of them are ACPI related.
 > 
 > 1) there are 5 thermal zones defined out of which only two provide
 > reasonable numbers it seems:
 > 
 > hw.acpi.thermal.tz4.temperature: 34.1C
 > hw.acpi.thermal.tz3.temperature: 0.1C
 > hw.acpi.thermal.tz2.temperature: 0.1C
 > hw.acpi.thermal.tz1.temperature: 0.1C
 > hw.acpi.thermal.tz0.temperature: 56.1C
 > 
 > my gut feeling is that tz0-tz3 may be the CPU cores and tz4 would be
 > the GPU (which does not work in BSD ATM, hence consistently lower
 > temp). I guess this is not a big deal (everything works) but I still
 > wonder how to fix it.

Not sure if anything needs fixing, but I only have Intel gear these 
days and am not up on the AMD side of things.  However, please show:

% sysctl dev.cpu
% sysctl hw.acpi.thermal

which may provide more clues.  Perhaps all 4 cores are in one package, 
in which case individual CPU temperatures may not be too meaningful.  I 
don't know whether there's any equivalent to coretemp(4) for AMD CPUs?

Yours won't use est(4) but perhaps powernow(0) - 0 meaning no manpage :) 
but both are in GENERIC kernels.  You should be able to glean from dmesg 
which driver/s are in use; a verbose dmesg.boot might come in handy.

 > 2) turbo mode: this is a more major issue. sysctl reports the
 > following for all four cores:
 > 
 > dev.cpu.0.cx_lowest: C2
 > dev.cpu.0.cx_supported: C1/1/0 C2/2/400
 > dev.cpu.0.freq_levels: 2100/4717 1800/3450 1400/2320
 > dev.cpu.0.freq: 2100
 > 
 > >From the intel CPUs w/ turbo mode I had before I know that there
 > should be (at least) a 2101 frequency indicating the turbo clock. This
 > frequency is absent, I suspect this means turbo mode does not work.

Or that these CPUs just don't have a turbo mode, as such?  I expect the 
specs on AMD's site should mention that, either way?

 > How can I debug this? I believe also that this AMD chip has multiple
 > frequencies above the base clock of 2100, so how would that show?

What leads you to believe that?  Where is this documented?

 > Loaded modules:
 > 
 > Id Refs Address            Size     Name
 >  1   23 0xffffffff80200000 1e79670  kernel
 >  2    1 0xffffffff8207b000 384858   zfs.ko
 >  3    2 0xffffffff82400000 ca38     opensolaris.ko
 >  4    1 0xffffffff8240d000 22b98    geom_eli.ko
 >  5    1 0xffffffff82431000 ac60     aesni.ko
 >  6    1 0xffffffff8243d000 1c520    fuse.ko
 >  7    1 0xffffffff82621000 358b     ums.ko
 >  8    1 0xffffffff82625000 223c4    ipfw.ko
 > 
 > I should note that I boot in legacy mode, not EFI.
 > 
 > asl dump available from http://llamapost.net/elitebook.asl

If it cxomes to that ..

 > Thanks a lot!
 > 
 > Johannes

Not much help, but I see noone else springing to your aid so far ..

cheers, Ian