如何在u-boot中显示当前时间

Question

I'm trying to display current time in the bootloader to calculate how much a function takes to be executed. I used the time.h library but it doesn't work perfectly. any idea? used code:

#include<stdio.h>
#include<time.h>
time_t t;
time(&t);
printf("\before watchdog init: %s", ctime(&t));

error: implicit declaration of function 'time' [-Werror=implicit-function-declaration]

error: implicit declaration of function 'ctime' [-Werror=implicit-function-declaration]

Answer 1

There is no need for any C code to display the current time. Just execute the shell command date .

To update the RTC time via the network use the sntp command. If your board does not have a real time clock, you can emulate it with configuration setting CONFIG_RTC_EMULATION=y.

If you still need a solution in C, look at the code in cmd/date.c:

                struct rtc_time tm;
                int rcode = 0;
                rcode = dm_rtc_get(dev, &tm);
                if (rcode) {
                        puts("## Get date failed\n");
                        break;
                }   

                printf ("Date: %4d-%02d-%02d Time: %2d:%02d:%02d\n",
                        tm.tm_year, tm.tm_mon, tm.tm_mday,
                        tm.tm_hour, tm.tm_min, tm.tm_sec);