Hi Gong Jun we need your insight on the w83667hg, please see below.
On Fri, Oct 2, 2009 at 9:23 PM, Mark Altern <mark.altern@xxxxxxxxx> wrote:
> On Fri, Oct 2, 2009 at 12:44 PM, Luca Tettamanti <kronos.it@xxxxxxxxx>
> wrote:
>> On Fri, Oct 2, 2009 at 7:16 PM, Mark Altern <mark.altern@xxxxxxxxx> wrote:
>> > The funny thing is that right after computer startsup, the lm_sensors
>> > report
>> > correct diode CPU temp, like around 36C, and fan is spinning at around
>> > 600rpm, but after idling a minutes or two, that value suddenly jump up
>> > to
>> > 47C and you hear the fan speeding up to 1100rmp, while the coretemps are
>> > still the same as before, further more, I touched the "cold" CPU heat
>> > sink,
>> > 47C is definitely NOT true. So how does the atk0110 work?
>>
>> It just report the value calculated by the firmware, the driver itself
>> does not perform any "adjustment" on the temperature.
[...]
> By the way, how does w83667 report/calculate the CPU temperature?
The native drivers reads from the sensor a 9bit digital value.
> Here is the DSDT file, thanks a lot for your help.
Hum, there are some serious dragons there... the relevant method
(HWT1) does what I expected it to do, but there some strange black
magic before it.
First of all it selects a logical device (0x0c) that is not documented
in the datasheet. During the first 2 reading, the temperature of the
CPU is compared to the temperature of the board; if the CPU is colder
than the board then the method stores something that _resembles_ the
delta between the two temp in a configuration register of the logical
device.
I guess it's some sort of calibration algorithm...
In pseudo code:
t1 = read temperature1 (mobo)
t2 = read temperature2 (cpu)
t1++
t1 = t1 ^ 0x80
t2 = t2 ^ 0x80
if (t1 > t2) {
enter extended function mode, logical device 0x0c
if (CRE0 & 0xf0) {
delta = t2 - t1
delta = delta >> 1
delta = delta + 3
CRE1 = CRE1 + delta
}
exit extended mode
}
where CRE0 and CRE1 are configuration register of the logical device.
Gong Jun do you have any idea of what's happening here?
Luca
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