Hi everyone,
I am using LS1043ARDB with Deos operating system and the application I am implementing involves the use of only one core.
I would like to read the temperatures reached by the chip with the Thermal Monitoring Unit (TMU) module that receives data from 5 sensors on the chip, as described in Chapter 35 in QorIQ LS1043A Reference Manual. I implemented the same temperature calibration points (Table 35-2) following the procedure on page 2219.
With the QorIQ just turned on and the box open I can read measurements of 35/40 °C from the TRITSR registers and they go up to 80/85 °C. Moreover I can touch with my hand the heatsink located inside the box, for this reason I believe that the real temperature is at least 10 °C below the measured value. Is the measurement procedure correct? Is there a temperature offset at board startup that increases the values?
I would also like to understand why the board reaches such high temperatures since the application I am loading on the board is trivial. I suspect that Deos at board startup turns on all 4 cores and peripherals. Does anyone know if it is possible to turn off cores except core 0 with a standard application and does anyone have sample code? Or is a special Deos boot required?
It is possible to doublecheck the code referring the TMU Linux driver (drivers/thermal/qoriq_thermal.c):