gonzui

    1: /*
    2:  *----------------------------------------------------------------------
    3:  *    micro T-Kernel 3.00.05
    4:  *
    5:  *    Copyright (C) 2006-2021 by Ken Sakamura.
    6:  *    This software is distributed under the T-License 2.2.
    7:  *----------------------------------------------------------------------
    8:  *
    9:  *    Released by TRON Forum(http://www.tron.org) at 2021/11.
   10:  *
   11:  *----------------------------------------------------------------------
   12:  */
   13: 
   14: /*
   15:  *      sys_timer.h (ARMv7-A)
   16:  *      Hardware-Dependent System Timer (SysTick) Processing
   17:  */
   18: 
   19: #ifndef _SYSDEPEND_CPU_CORE_SYSTIMER_
   20: #define _SYSDEPEND_CPU_CORE_SYSTIMER_
   21: 
   22: /*
   23:  * Timer start processing
   24:  *      Initialize the timer and start the periodical timer interrupt.
   25:  */
   26: Inline void knl_start_hw_timer( void )
   27: {
   28:         UINT   imask;
   29:         UD     cnt;
   30: 
   31:         DI(imask);
   32: 
   33:         /* Convert microseconds to timer values */
   34:         cnt = (((TIMER_PERIOD * 1000) * COUNT_PER_SEC) / 1000000LL);
   35: 
   36:         out_b(OSTM0_TT, 0x01);         /* Stop timer */
   37:         out_b(OSTM0_CTL, 0x01);                /* Set Interval timer mode & Interrupt enabled */
   38:         out_w(OSTM0_CMP, (UW)cnt);     /* Set compare register */
   39:         out_b(OSTM0_TS, 0x01);         /* Start Timer */
   40: 
   41:         EnableInt(INTNO_SYSTICK, INTPRI_SYSTICK);      /* Enable interrupt(INTC level) */
   42: 
   43:         EI(imask);
   44: }
   45: 
   46: /*
   47:  * Clear timer interrupt
   48:  *      Clear the timer interrupt request. Depending on the type of
   49:  *      hardware, there are two timings for clearing: at the beginning
   50:  *      and the end of the interrupt handler.
   51:  *      'clear_hw_timer_interrupt()' is called at the beginning of the
   52:  *      timer interrupt handler.
   53:  *      'end_of_hw_timer_interrupt()' is called at the end of the timer
   54:  *      interrupt handler.
   55:  *      Use either or both according to hardware.
   56:  */
   57: Inline void knl_clear_hw_timer_interrupt( void )
   58: {
   59: }
   60: 
   61: Inline void knl_end_of_hw_timer_interrupt( void )
   62: {
   63:         disint();      /* disint() in front of the EOI to prevent inadvertent interrupts. */
   64:         EndOfInt(INTNO_SYSTICK);
   65: }
   66: 
   67: /*
   68:  * Timer stop processing
   69:  *      Stop the timer operation.
   70:  *      Called when system stops.
   71:  */
   72: Inline void knl_terminate_hw_timer( void )
   73: {
   74:         out_b(OSTM0_TT, 0x01);         /* Stop Timer */
   75: }
   76: 
   77: /*
   78:  * Get processing time from the previous timer interrupt to the
   79:  * current (nanosecond)
   80:  *      Consider the possibility that the timer interrupt occurred
   81:  *      during the interrupt disable and calculate the processing time
   82:  *      within the following
   83:  *      range: 0 <= Processing time < CFN_TIMER_PERIOD
   84:  */
   85: Inline UW knl_get_hw_timer_nsec( void )
   86: {
   87:         UW                 ofs, max;
   88: 
   89:         max = in_w(OSTM0_CMP);         /* Timer cycle value */
   90:         ofs = in_w(OSTM0_CNT);         /* Current timer value (Down count) */
   91: 
   92:         return ((max - ofs) * NSEC_PER_COUNT);
   93: }
   94: 
   95: #endif /* _SYSDEPEND_CPU_CORE_SYSTIMER_ */