software/libbase/timer.c

   1 #include <hw/timer.h>
   2 #include <hw/identifier.h>
   3
   4 #include "timer.h"
   5
   6 unsigned int get_system_frequency(void)
   7 {
   8         return (CSR_IDENTIFIER_FREQ3 << 24)
   9                 |(CSR_IDENTIFIER_FREQ2 << 16)
  10                 |(CSR_IDENTIFIER_FREQ1 << 8)
  11                 |CSR_IDENTIFIER_FREQ0;
  12 }
  13
  14 void timer_enable(int en)
  15 {
  16         CSR_TIMER0_EN = en;
  17 }
  18
  19 unsigned int timer_get(void)
  20 {
  21         return (CSR_TIMER0_COUNT3 << 24)
  22                 |(CSR_TIMER0_COUNT2 << 16)
  23                 |(CSR_TIMER0_COUNT1 << 8)
  24                 |CSR_TIMER0_COUNT0;
  25 }
  26
  27 void timer_set_counter(unsigned int value)
  28 {
  29         CSR_TIMER0_COUNT3 = (value & 0xff000000) >> 24;
  30         CSR_TIMER0_COUNT2 = (value & 0x00ff0000) >> 16;
  31         CSR_TIMER0_COUNT1 = (value & 0x0000ff00) >> 8;
  32         CSR_TIMER0_COUNT0 = value & 0x000000ff;
  33 }
  34
  35 void timer_set_reload(unsigned int value)
  36 {
  37         CSR_TIMER0_RELOAD3 = (value & 0xff000000) >> 24;
  38         CSR_TIMER0_RELOAD2 = (value & 0x00ff0000) >> 16;
  39         CSR_TIMER0_RELOAD1 = (value & 0x0000ff00) >> 8;
  40         CSR_TIMER0_RELOAD0 = value & 0x000000ff;
  41 }
  42
  43 void busy_wait(unsigned int ds)
  44 {
  45         timer_enable(0);
  46         timer_set_reload(0);
  47         timer_set_counter(get_system_frequency()/10*ds);
  48         timer_enable(1);
  49         while(timer_get());
  50 }