From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Date: Thu, 01 Nov 2012 17:17:07 +0000 Subject: Re: [lm-sensors] [PATCH 9/9] hwmon: (it87) Report thermal sensor type as Intel PECI if appropriate Message-Id: <20121101171707.GA2766@roeck-us.net> List-Id: References: <1351448401-13985-10-git-send-email-linux@roeck-us.net> In-Reply-To: <1351448401-13985-10-git-send-email-linux@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lm-sensors@vger.kernel.org On Thu, Nov 01, 2012 at 05:37:57PM +0100, Jean Delvare wrote: > On Thu, 1 Nov 2012 06:40:51 -0700, Guenter Roeck wrote: > > On Thu, Nov 01, 2012 at 01:56:07PM +0100, Jean Delvare wrote: > > > On Mon, 29 Oct 2012 10:28:30 -0700, Guenter Roeck wrote: > > > > The BIOS, presumably. It does it on my board, but wrongly. It sets it > > > > to 97 degrees C, while the CPU's Tcrit is 105 degrees C. I fixed the > > > > offset to 105, and now the reported temperature matches the CPU temperature > > > > (and moves with it). This is how I found out about PECI support in the > > > > first place. > > > > > > In which register is the PECI temperature offset value stored? I am > > > looking at the IT8720F datasheet and I can't find it. > > > > On IT8728F it is in the diode zero degree adjust registers. > > I found this from experiments; it is not mentioned in the datasheet. > > I would guess it is the same on the other chips, though I can not test > > it on those. > > On an IT8720F chip with temp3 configured for PECI: > > temp1_offset: 0 > temp2_offset: 0 > temp3_offset: -128000 > > I'm unsure how to interpret this -128000... This value is definitely > not neutral, doesn't sound very realistic. I would expect a positive > number for PECI. Maybe the offset register should be treated as > unsigned in PECI mode? Or maybe its value is irrelevant for the IT8720F > in PECI mode. > > # grep . /sys/class/hwmon/hwmon2/device/temp3* > /sys/class/hwmon/hwmon2/device/temp3_alarm:0 > /sys/class/hwmon/hwmon2/device/temp3_beep:1 > /sys/class/hwmon/hwmon2/device/temp3_input:25000 > /sys/class/hwmon/hwmon2/device/temp3_max:70000 > /sys/class/hwmon/hwmon2/device/temp3_min:127000 > /sys/class/hwmon/hwmon2/device/temp3_offset:-128000 > /sys/class/hwmon/hwmon2/device/temp3_type:6 > > This is with an it87 driver including all your recent patches. It you > have ideas or theories, I'm interested. > Hi Jean, I agree. The alternative (+128 degrees C) sounds a bit high, though. Maybe there is another register on IT8720F to store Tjmax ? Did you check in the register map if there is a register value that happens to match it ? What happens if you change the offset register value to, say, 100 ? Does the reported temperature change as well ? Another maybe dumb question - is this with Intel or AMD CPU ? Because if it is AMD, it would not be PECI but AMDSI (something to fix if someone has a system w/ IT87xx and AMD CPU). Thanks, Guenter _______________________________________________ lm-sensors mailing list lm-sensors@lm-sensors.org http://lists.lm-sensors.org/mailman/listinfo/lm-sensors