* Copyright (c) 2002 Wasabi Systems, Inc.

/* $NetBSD: ns16550.c,v 1.5 2022/09/05 14:14:42 tsutsui Exp $ */

/*
* Copyright (c) 2002 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Jason R. Thorpe for Wasabi Systems, Inc.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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.
*/

/*
* This file provides the cons_init() function and console I/O routines
* for boards that use 16550-compatible UARTs.
*/

#include <sys/types.h>
#include <dev/ic/comreg.h>
#include <lib/libsa/stand.h>

#include "board.h"

#ifdef NS16550_AX4
#define INB(x) *((volatile uint8_t *) (CONADDR + ((x) * 4)))
#define OUTB(x, v) *((volatile uint8_t *) (CONADDR + ((x) * 4))) = (v)
#else
#define INB(x) *((volatile uint8_t *) (CONADDR + (x)))
#define OUTB(x, v) *((volatile uint8_t *) (CONADDR + (x))) = (v)
#endif

#ifndef NS16550_FREQ
#define NS16550_FREQ COM_FREQ
#endif

static int
comspeed(int speed)
{
#define divrnd(n, q) (((n)*2/(q)+1)/2) /* divide and round off */

int x, err;

if (speed <= 0)
return (-1);
x = divrnd((NS16550_FREQ / 16), speed);
if (x <= 0)
return (-1);
err = divrnd((((quad_t)NS16550_FREQ) / 16) * 1000, speed * x) - 1000;
if (err < 0)
err = -err;
if (err > COM_TOLERANCE)
return (-1);
return (x);
#undef divrnd
}

void
cons_init(void)
{
int rate;

OUTB(com_cfcr, LCR_DLAB);
rate = comspeed(CONSPEED);
OUTB(com_dlbl, rate);
OUTB(com_dlbh, rate >> 8);
OUTB(com_cfcr, LCR_8BITS);
OUTB(com_mcr, MCR_DTR | MCR_RTS);
OUTB(com_fifo,
FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
OUTB(com_ier, 0);
}

int
getchar(void)
{
uint8_t stat;

while (!ISSET(stat = INB(com_lsr), LSR_RXRDY))
/* spin */ ;
return (INB(com_data));
}

static void
iputchar(int c)
{
uint8_t stat;
int timo;

/* Wait for any pending transmission to finish. */
timo = 50000;
while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo)
/* spin */ ;

OUTB(com_data, c);

/* Wait for this transmission to complete. */
timo = 1500000;
while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo)
/* spin */ ;

/* Clear any interrupts generated by this transmission. */
(void) INB(com_iir);
}

void
putchar(int c)
{

if (c == '\n')
iputchar('\r');
iputchar(c);
}