/*      $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;
}