/*
 * Copyright 2005, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Copyright 2001, Travis Geiselbrecht. All rights reserved.
 * Distributed under the terms of the NewOS License.
 */


#include <boot/stage2.h>
#include <kernel.h>

#include <arch/int.h>
#include <arch/cpu.h>

#include <console.h>
#include <debug.h>
#include <timer.h>
#include <interrupts.h>
#include <safemode.h>

#include <arch/timer.h>

#include <arch/x86/smp_priv.h>
#include <arch/x86/timer.h>


//#define TRACE_TIMER
#ifdef TRACE_TIMER
#       define TRACE(x...) dprintf("arch_timer: " x)
#else
#       define TRACE(x...) ;
#endif


extern timer_info gPITTimer;
extern timer_info gAPICTimer;
extern timer_info gHPETTimer;

static timer_info *sTimers[] = {
        &gHPETTimer,
        &gAPICTimer,
        &gPITTimer,
        NULL
};

static timer_info *sTimer = NULL;

void
arch_timer_set_hardware_timer(bigtime_t timeout)
{
        TRACE("arch_timer_set_hardware_timer: timeout %" B_PRIdBIGTIME "\n", timeout);
        sTimer->set_hardware_timer(timeout);
}


void
arch_timer_clear_hardware_timer(void)
{
        TRACE("arch_timer_clear_hardware_timer\n");
        sTimer->clear_hardware_timer();
}


static void
sort_timers(timer_info *timers[], int numTimers)
{
        timer_info *tempPtr;
        int max = 0;
        int i = 0;
        int j = 0;

        for (i = 0; i < numTimers - 1; i++) {
                max = i;
                for (j = i + 1; j < numTimers; j++) {
                        if (timers[j]->get_priority() > timers[max]->get_priority())
                                max = j;
                }
                if (max != i) {
                        tempPtr = timers[max];
                        timers[max] = timers[i];
                        timers[i] = tempPtr;
                }
        }

#if 0
        for (i = 0; i < numTimers; i++)
                dprintf(" %s: priority %d\n", timers[i]->name, timers[i]->get_priority());
#endif
}


int
arch_init_timer(kernel_args *args)
{
        // Sort timers by priority
        sort_timers(sTimers, (sizeof(sTimers) / sizeof(sTimers[0])) - 1);

        timer_info *timer = NULL;
        cpu_status state = disable_interrupts();

        for (int i = 0; (timer = sTimers[i]) != NULL; i++) {
                if (timer->init(args) == B_OK)
                        break;
        }

        sTimer = timer;

        if (sTimer != NULL) {
                dprintf("arch_init_timer: using %s timer.\n", sTimer->name);
        } else {
                panic("No system timers were found usable.\n");
        }

        restore_interrupts(state);

        return 0;
}