FreeBSD-5.3/sys/dev/sx/sx_util.c
/*
* Device driver for Specialix I/O8+ multiport serial card.
*
* Copyright 2003 Frank Mayhar <frank@exit.com>
*
* Derived from the "si" driver by Peter Wemm <peter@netplex.com.au>, using
* lots of information from the Linux "specialix" driver by Roger Wolff
* <R.E.Wolff@BitWizard.nl> and from the Intel CD1865 "Intelligent Eight-
* Channel Communications Controller" datasheet. Roger was also nice
* enough to answer numerous questions about stuff specific to the I/O8+
* not covered by the CD1865 datasheet.
*
* 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
* notices, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notices, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY ``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 AUTHORS BE LIABLE.
*
* $FreeBSD: src/sys/dev/sx/sx_util.c,v 1.1 2004/04/11 19:32:20 imp Exp $
*/
#include "opt_debug_sx.h"
/* Utility and support routines for the Specialix I/O8+ driver. */
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/tty.h>
#include <machine/resource.h>
#include <machine/bus.h>
#include <machine/clock.h>
#include <sys/rman.h>
#include <dev/sx/cd1865.h>
#include <dev/sx/sxvar.h>
#include <dev/sx/sx.h>
#include <dev/sx/sx_util.h>
/*
* sx_probe_io8()
* Probe the board to verify that it is a Specialix I/O8+.
*
* Description:
* This is called by sx_pci_attach() (and possibly in the future by
* sx_isa_attach()) to verify that the card we're attaching to is
* indeed a Specialix I/O8+. To do this, we check for the Prescaler
* Period Register of the CD1865 chip and for the Specialix signature
* on the DSR input line of each channel. These lines, along with the
* RTS output lines, are wired down in hardware.
*/
int
sx_probe_io8(
device_t dev)
{
struct sx_softc *sc;
unsigned char val1, val2;
int i;
sc = device_get_softc(dev);
/*
* Try to write the Prescaler Period Register, then read it back,
* twice. If this fails, it's not an I/O8+.
*/
sx_cd1865_out(sc, CD1865_PPRL, 0x5a);
DELAY(1);
val1 = sx_cd1865_in(sc, CD1865_PPRL);
sx_cd1865_out(sc, CD1865_PPRL, 0xa5);
DELAY(1);
val2 = sx_cd1865_in(sc, CD1865_PPRL);
if ((val1 != 0x5a) || (val2 != 0xa5))
return(1);
/*
* Check the lines that Specialix uses as board identification.
* These are the DSR input and the RTS output, which are wired
* down.
*/
val1 = 0;
for (i = 0; i < 8; i++) {
sx_cd1865_out(sc, CD1865_CAR, i); /* Select channel. */
if (sx_cd1865_in(sc, CD1865_MSVR) & CD1865_MSVR_DSR) /* Set? */
val1 |= 1 << i; /* OR it in. */
}
#ifdef notdef
val2 = 0;
for (i = 0; i < 8; i++) {
sx_cd1865_out(sc, CD1865_CAR, i); /* Select channel. */
if (sx_cd1865_in(sc, CD1865_MSVR) & CD1865_MSVR_RTS) /* Set? */
val2 |= 1 << i; /* OR it in. */
}
/*
* They managed to switch the bit order between the docs and
* the IO8+ card. The new PCI card now conforms to old docs.
* They changed the PCI docs to reflect the situation on the
* old card.
*/
val2 = (bp->flags & SX_BOARD_IS_PCI) ? 0x4d : 0xb2;
#endif /* notdef */
if (val1 != 0x4d) {
if (bootverbose)
device_printf(dev,
"Specialix I/O8+ ID 0x4d not found (0x%02x).\n",
val1);
return(1);
}
return(0); /* Probed successfully. */
}
/*
* sx_init_CD1865()
* Hard-reset and initialize the I/O8+ CD1865 processor.
*
* Description:
* This routine does a hard reset of the CD1865 chip and waits for it
* to complete. (The reset should complete after 500us; we wait 1ms
* and fail if we time out.) We then initialize the CD1865 processor.
*/
int
sx_init_cd1865(
struct sx_softc *sc,
int unit)
{
int s;
unsigned int to;
s = spltty();
disable_intr();
sx_cd1865_out(sc, CD1865_GSVR, 0x00); /* Clear the GSVR. */
sx_cd1865_wait_CCR(sc, 0); /* Wait for the CCR to clear. */
sx_cd1865_out(sc, CD1865_CCR, CD1865_CCR_HARDRESET); /* Reset CD1865. */
enable_intr();
to = SX_GSVR_TIMEOUT/5;
while (to-- > 0) {
if (sx_cd1865_in(sc, CD1865_GSVR) == 0xff)
break;
DELAY(5);
}
if (to == 0) {
splx(s);
printf("sx%d: Timeout waiting for reset.\n", unit);
return(EIO);
}
/*
* The high five bits of the Global Interrupt Vector Register is
* used to identify daisy-chained CD1865 chips. The I/O8+ isn't
* daisy chained, but we have to initialize the field anyway.
*/
sx_cd1865_out(sc, CD1865_GIVR, SX_CD1865_ID);
/* Clear the Global Interrupting Channel register. */
sx_cd1865_out(sc, CD1865_GICR, 0);
/*
* Set the Service Match Registers to the appropriate values. See
* the cd1865.h include file for more information.
*/
sx_cd1865_out(sc, CD1865_MSMR, CD1865_ACK_MINT); /* Modem. */
sx_cd1865_out(sc, CD1865_TSMR, CD1865_ACK_TINT); /* Transmit. */
sx_cd1865_out(sc, CD1865_RSMR, CD1865_ACK_RINT); /* Receive. */
/*
* Set RegAckEn in the Service Request Configuration Register;
* we'll be acknowledging service requests in software, not
* hardware.
*/
sx_cd1865_bis(sc, CD1865_SRCR, CD1865_SRCR_REGACKEN);
/*
* Set the CD1865 timer tick rate. The value here is the processor
* clock rate (in MHz) divided by the rate in ticks per second. See
* commentary in sx.h.
*/
sx_cd1865_out(sc, CD1865_PPRH, SX_CD1865_PRESCALE >> 8);
sx_cd1865_out(sc, CD1865_PPRL, SX_CD1865_PRESCALE & 0xff);
splx(s);
return(0);
}
#ifdef notyet
/*
* Set the IRQ using the RTS lines that run to the PAL on the board....
*
* This is a placeholder for ISA support, if that's ever implemented. This
* should _only_ be called from sx_isa_attach().
*/
int
sx_set_irq(
struct sx_softc *sc,
int unit,
int irq)
{
register int virq;
register int i, j;
switch (irq) {
/* In the same order as in the docs... */
case 15:
virq = 0;
break;
case 12:
virq = 1;
break;
case 11:
virq = 2;
break;
case 9:
virq = 3;
break;
default:
printf("sx%d: Illegal irq %d.\n", unit, irq);
return(0);
}
for (i = 0; i < 2; i++) {
sx_cd1865_out(sc, CD1865_CAR, i); /* Select channel. */
j = ((virq >> i) & 0x1) ? MSVR_RTS : 0;
sx_cd1865_out(sc, CD1865_MSVRTS, j);
}
return(1);
}
#endif /* notyet */
/*
* sx_int_port()
* Determine the port that interrupted us.
*
* Description:
* This routine checks the Global Interrupting Channel Register (GICR)
* to find the port that caused an interrupt. It returns a pointer to
* the sx_port structure of the interrupting port, or NULL if there was
* none.
*
* XXX - check type/validity of interrupt?
*/
struct sx_port *
sx_int_port(
struct sx_softc *sc,
int unit)
{
unsigned char chan;
struct sx_port *pp;
chan = (sx_cd1865_in(sc, CD1865_GSCR2|SX_EI) & CD1865_GICR_CHAN_MASK)
>> CD1865_GICR_CHAN_SHIFT;
DPRINT((NULL, DBG_INTR, "Intr chan %d\n", chan));
if (chan < CD1865_NUMCHAN) {
pp = sc->sc_ports + (int)chan;
return(pp);
}
printf("sx%d: False interrupt on port %d.\n", unit, chan);
return(NULL);
}