/* clkinit.c - clkinit (BeagleBone Black) */

#include 

uint32  clktime;                /* Seconds since boot                   */
uint32  count1000;              /* ms since last clock tick             */
qid16   sleepq;                 /* Queue of sleeping processes          */
uint32  preempt;                /* Preemption counter                   */

/*------------------------------------------------------------------------
 * clkinit  -  Initialize the clock and sleep queue at startup
 *------------------------------------------------------------------------
 */
void    clkinit(void)
{
        volatile struct am335x_timer1ms *csrptr =
        (volatile struct am335x_timer1ms *)AM335X_TIMER1MS_ADDR;
                        /* Pointer to timer CSR in BBoneBlack   */
        volatile uint32 *clkctrl =
                        (volatile uint32 *)AM335X_TIMER1MS_CLKCTRL_ADDR;

        *clkctrl = AM335X_TIMER1MS_CLKCTRL_EN;
        while((*clkctrl) != 0x2) /* Do nothing */ ;

        /* Reset the timer module */

        csrptr->tiocp_cfg |= AM335X_TIMER1MS_TIOCP_CFG_SOFTRESET;

        /* Wait until the reset is complete */

        while((csrptr->tistat & AM335X_TIMER1MS_TISTAT_RESETDONE) == 0)
                /* Do nothing */ ;

        /* Set interrupt vector for clock to invoke clkint */

        set_evec(AM335X_TIMER1MS_IRQ, (uint32)clkhandler);

        sleepq = newqueue();    /* Allocate a queue to hold the delta   */
                                /*   list of sleeping processes         */

        preempt = QUANTUM;      /* Set the preemption time              */

        clktime = 0;            /* Start counting seconds               */
        count1000 = 0;
        /* The following values are calculated for a    */
        /*   timer that generates 1ms tick rate         */

        csrptr->tpir = 1000000;
        csrptr->tnir = 0;
        csrptr->tldr = 0xFFFFFFFF - 26000;

        /* Set the timer to auto reload */

        csrptr->tclr = AM335X_TIMER1MS_TCLR_AR;

        /* Start the timer */

        csrptr->tclr |= AM335X_TIMER1MS_TCLR_ST;

        /* Enable overflow interrupt which will generate */
        /*   an interrupt every 1 ms                     */

        csrptr->tier = AM335X_TIMER1MS_TIER_OVF_IT_ENA;

        /* Kickstart the timer */

        csrptr->ttgr = 1;

        return;
}