software/libbase/time.c

   1 #include <hw/csr.h>
   2 #include <time.h>
   3
   4 void time_init(void)
   5 {
   6         int t;
   7
   8         timer0_en_write(0);
   9         t = 2*identifier_frequency_read();
  10         timer0_reload_write(t);
  11         timer0_load_write(t);
  12         timer0_en_write(1);
  13 }
  14
  15 int elapsed(int *last_event, int period)
  16 {
  17         int t, dt;
  18
  19         timer0_update_value_write(1);
  20         t = timer0_reload_read() - timer0_value_read();
  21         dt = t - *last_event;
  22         if(dt < 0)
  23                 dt += timer0_reload_read();
  24         if((dt > period) || (dt < 0)) {
  25                 *last_event = t;
  26                 return 1;
  27         } else
  28                 return 0;
  29 }