Thermal sensor of iMX8X

[Kazuma_Sasaki]

Hi,

I could get temperature via SCFW API (sc_misc_get_temp) . But, I would like to confirm a few points.

Q1. I was getting following result with MEK and linux bsp.

thermal_zone0 is CPU temperature. thermal_zone1 is DDR controller temperature. is it right?

If yes, These temperature difference of 25°C between CPU and DDR controller. Is this reasonable?

root@imx8qxpmek:~# cat /sys/class/thermal/thermal_zone0/temp
45000

root@imx8qxpmek:~# cat /sys/class/thermal/thermal_zone1/temp
70000

Q2. Linux BSP is able to chose SC_R_PMIC_0, SC_R_PMIC_1 and SC_R_PMIC_2 for resource parameter.

Which module's temperature can I get by specifying these resources?

Copy from linux_4.14.98_2.3.0_ga/drivers/thermal/imx_sc_thermal.c

Best Regards,

Kazuma Sasaki.

[igorpadykov]

Hi Kazuma

SC_R_PMIC_0 - Center of die

SC_R_PMIC_1 - Vicinity of SW1

SC_R_PMIC_2 - Vicinity of SW2

Best regards
igor

[Kazuma_Sasaki]

Dear Igor,

I got it. thanks.

Best Regards,

Kazuma Sasaki.

[igorpadykov · Accepted solution]

Hi Kazuma

1. > ..difference of 25°C between CPU and DDR controller. Is this reasonable?

DRC (DDR) temperature sensor readings are wrong due to erratum ERR050055
https://www.nxp.com/docs/en/errata/IMX8X_0N95W.pdf

2. SC_R_PMIC_0, SC_R_PMIC_1 and SC_R_PMIC_2 are PMIC temperature
sensors described in PF8100 datasheet
https://www.nxp.com/docs/en/data-sheet/PF8100_PF8200.pdf

Best regards
igor
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[Kazuma_Sasaki]

Hi Igor,

Thank you for your support.

Let me confirm once again. What is different SC_R_PMIC_0, SC_R_PMIC_1 and SC_R_PMIC_2?

Best Regards,

Kazuma Sasaki.

[igorpadykov]

Hi Kazuma

> What is different SC_R_PMIC_0, SC_R_PMIC_1 and SC_R_PMIC_2

these are PMIC temperature sensors, described in PF8100 datasheet
https://www.nxp.com/docs/en/data-sheet/PF8100_PF8200.pdf

Best regards
igor

[Kazuma_Sasaki]

Hi Igor,

I am sorry for not explaining enough.

PF8100 has ten temperature sensors. Which sensor temperature can be acquired by selecting SC_R_PMIC_0?

Also, I would to know about SC_R_PMIC_1 and SC_R_PMIC_2.

Best Regards,

Kazuma Sasaki.

[igorpadykov]

>. Which sensor temperature can be acquired by selecting SC_R_PMIC_0?

1. Center of die

and so on.

Best regards
igor

[Kazuma_Sasaki]

Hi Igor,

Please let me confirm one thing.

What is the difference between SC_R_PMIC_0, SC_R_PMIC_1 and SC_R_PMIC_2?

Before you told me that these settings will be return the temperature of center of die.

How should I use these settings properly?

MEK has one PMIC. At that case, can we select SC_R_PMIC_1 and SC_R_PMIC_2?

Best Regards,

Kazuma Sasaki.

[Kazuma_Sasaki]

Hi Igor,

I appreciate your support. I got it.

Best Regards,

Kazuma Sasaki.