topic Re: Read CPU temperature in u-boot in i.MX Processors

Read CPU temperature in u-boot

ko-hey — Tue, 13 Dec 2016 06:30:17 GMT

Hi all

My customer is using i.MX6S and L3.10.17.

I want to check whether the value changes or not when I changed TEMPERATURE_HOT parameter in soc.c.

Does i.MX6's register change when user changed TEMPERATURE_HOT parameter in soc.c ?

I guess that it will change the value of TEMPERATURE_HOT when user changed TEMPERATURE_HOT parameter in soc.c.

Am I correct ?

If my understanding is wrong, is it just reading the value of the temperature sensor?

Ko-hey

Original Attachment has been moved to: soc.c.zip

Re: Read CPU temperature in u-boot

ko-hey — Thu, 22 Dec 2016 08:43:26 GMT

Could someone follow and answer this question ?

Ko-hey

Re: Read CPU temperature in u-boot

BiyongSUN — Thu, 22 Dec 2016 09:16:11 GMT

It is to set a hot point to compare to the value gets from thermal sensor, to decide in the uboot stage if the temperature if it is fine for boot to the next stage here is linux.

void check_cpu_temperature(void)
{
int cpu_tmp = 0;

cpu_tmp = read_cpu_temperature();
while (cpu_tmp > TEMPERATURE_MIN && cpu_tmp < TEMPERATURE_MAX) {
if (cpu_tmp >= TEMPERATURE_HOT) {
printf("CPU is %d C, too hot to boot, waiting...\n",
cpu_tmp);
udelay(5000000);
cpu_tmp = read_cpu_temperature();
} else
break;
}
if (cpu_tmp > TEMPERATURE_MIN && cpu_tmp < TEMPERATURE_MAX)
printf("CPU: Temperature %d C, calibration data: 0x%x\n",
cpu_tmp, fuse);
else
printf("CPU: Temperature: can't get valid data!\n");
}