/*      $NetBSD: timer_hb.c,v 1.21 2024/01/15 20:21:50 thorpej Exp $    */

/*-
 * Copyright (c) 1996 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jason R. Thorpe.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: timer_hb.c,v 1.21 2024/01/15 20:21:50 thorpej Exp $");

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/intr.h>

#include <uvm/uvm_extern.h>

#include <machine/cpu.h>
#include <machine/bus.h>
#include <machine/vectors.h>

#include <dev/clock_subr.h>

#include <news68k/news68k/isr.h>
#include <news68k/news68k/clockvar.h>

#include <news68k/dev/hbvar.h>

#include "ioconf.h"

/*
 * interrupt level for clock
 */

#define TIMER_LEVEL 6
#define TIMER_SIZE 8    /* XXX */

static int timer_hb_match(device_t, cfdata_t, void *);
static void timer_hb_attach(device_t, device_t, void *);
static void timer_hb_initclocks(int, int);
void clock_intr(struct clockframe);

static inline void leds_intr(void);

extern void _isr_clock(void);   /* locore.s */

CFATTACH_DECL_NEW(timer_hb, 0,
    timer_hb_match, timer_hb_attach, NULL, NULL);

static volatile uint8_t *ctrl_timer; /* XXX */

extern volatile u_char *ctrl_led; /* XXX */

static int
timer_hb_match(device_t parent, cfdata_t cf, void *aux)
{
        struct hb_attach_args *ha = aux;
        static int timer_hb_matched;

        /* Only one timer, please. */
        if (timer_hb_matched)
                return 0;

        if (strcmp(ha->ha_name, timer_cd.cd_name))
                return 0;

        if (ha->ha_ipl == -1)
                ha->ha_ipl = TIMER_LEVEL;

        ha->ha_size = TIMER_SIZE;

        timer_hb_matched = 1;

        return 1;
}

static void
timer_hb_attach(device_t parent, device_t self, void *aux)
{
        struct hb_attach_args *ha = aux;

        if (ha->ha_ipl != TIMER_LEVEL)
                panic("clock_hb_attach: wrong interrupt level");

        ctrl_timer = (uint8_t *)(ha->ha_address); /* XXX needs bus_space */

        printf("\n");

        timer_config(timer_hb_initclocks);

#if 0 /* XXX this will be done in timer_hb_initclocks() */
        vec_set_entry(VECI_INTRAV0 + ha->ha_ipl, _isr_clock);
#endif
}

/*
 * Set up the interval timer (enable clock interrupts).
 * Leave stathz 0 since there is no secondary clock available.
 * Note that clock interrupts MUST STAY DISABLED until here.
 */
static void
timer_hb_initclocks(int prof, int stat)
{
        int s;

        s = splhigh();

        /* Install isr (in locore.s) that calls clock_intr(). */
        vec_set_entry(VECI_INTRAV0 + TIMER_LEVEL, _isr_clock);

        /* enable the clock */
        *ctrl_timer = 1;
        splx(s);
}

/*
 * Clock interrupt handler.
 * This is called by the "custom" interrupt handler.
 *
 * from sun3/sun3x/clock.c -tsutsui
 */
void
clock_intr(struct clockframe cf)
{
#ifdef  LED_IDLE_CHECK
        extern char _Idle[];    /* locore.s */
#endif

        /* Pulse the clock intr. enable low. */
        *ctrl_timer = 0;
        *ctrl_timer = 1;

        m68k_count_intr(TIMER_LEVEL);

        /* Entertainment! */
#ifdef  LED_IDLE_CHECK
        if (cf.cf_pc == (long)_Idle)
#endif
                leds_intr();

        /* Call common clock interrupt handler. */
        hardclock(&cf);
}

/* heartbeat LED */
#define LED0    0x01
#define LED1    0x02

static inline void
leds_intr(void)
{
        static u_char led_countdown, led_stat;
        u_char i;

        if (led_countdown) {
                led_countdown--;
                return;
        }

        i = led_stat ^ LED0;
        *ctrl_led = i;
        led_stat = i;
        led_countdown = hz;
}