.\" Copyright (c) 1990, 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the Systems Programming Group of the University of Utah Computer
.\" Science Department.
.\" 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. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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
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.\"
.\"     from: @(#)dca.4	5.2 (Berkeley) 3/27/91
.\"	from: com.4,v 1.1 1993/08/06 11:19:07 cgd Exp
.\"	from: sio.4,v 1.16 1995/06/26 06:05:30 bde Exp $
.\" $FreeBSD: head/share/man/man4/cy.4 263142 2014-03-14 03:07:51Z eadler $
.\"
.Dd May 24, 2004
.Dt CY 4
.Os
.Sh NAME
.Nm cy
.Nd Cyclades Cyclom-Y serial driver
.Sh SYNOPSIS
For one ISA card:
.Bd -ragged -offset indent -compact
.Cd "device cy"
.Pp
In
.Pa /boot/device.hints :
.Cd hint.cy.0.at="isa"
.Cd hint.cy.0.irq="10"
.Cd hint.cy.0.maddr="0xd4000"
.Cd hint.cy.0.msize="0x2000"
.Ed
.Pp
For two ISA cards:
.Bd -ragged -offset indent -compact
.Cd "device cy"
.Pp
In
.Pa /boot/device.hints :
.Cd hint.cy.0.at="isa"
.Cd hint.cy.0.irq="10"
.Cd hint.cy.0.maddr="0xd4000"
.Cd hint.cy.0.msize="0x2000"
.Cd hint.cy.1.at="isa"
.Cd hint.cy.1.irq="11"
.Cd hint.cy.1.maddr="0xd6000"
.Cd hint.cy.1.msize="0x2000"
.Ed
.Pp
For PCI cards:
.Bd -ragged -offset indent -compact
.Cd "device cy"
.Cd "options CY_PCI_FASTINTR"
.Pp
No lines are required in
.Pa /boot/device.hints
for PCI cards.
.Ed
.Pp
Minor numbering:
.Bd -literal -offset indent -compact
0b\fIMMMMMMMMMMMMMMMMxxxxxxxxOLIMMMMM\fR
                          call\fBO\fRut
                           \fBL\fRock
                            \fBI\fRnitial
  \fBMMMMMMMMMMMMMMMM           MMMMMM\fRinor
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides support for Cirrus Logic CD1400-based
.Tn EIA
.Tn RS-232C
.Pf ( Tn CCITT
.Tn V.24 )
communications interfaces (ports) on Cyclades Cyclom-Y boards.
Each CD1400 provides 4 ports.
Cyclom-Y boards with various numbers of CD1400's are available.
This driver supports up to 8 CD1400's (32 ports) per board.
.Pp
Input and output for each line may set independently
to the following speeds:
50, 75, 110, 134.5, 150, 300, 600, 1200, 1800, 2400, 4800, 9600,
19200, 38400, 57600, or 115200 bps.
Other speeds of up to 150000 are supported by the termios interface
but not by the sgttyb compatibility interface.
The CD1400 is not fast enough to handle speeds above 115200 bps
effectively.
It can transmit on a single line at slightly more than 115200 bps,
but when 4 lines are active in both directions its limit is about
90000 bps on each line.
.\" XXX the following should be true for all serial drivers and
.\" should not be repeated in the man pages for all serial drivers.
.\" It was copied from sio.4.  The only change was s/sio/cy/g.
.Pp
Serial ports controlled by the
.Nm
driver can be used for both `callin' and `callout'.
For each port there is a callin device and a callout device.
The minor number of the callout device is 128 higher
than that of the corresponding callin port.
The callin device is general purpose.
Processes opening it normally wait for carrier
and for the callout device to become inactive.
The callout device is used to steal the port from
processes waiting for carrier on the callin device.
Processes opening it do not wait for carrier
and put any processes waiting for carrier on the callin device into
a deeper sleep so that they do not conflict with the callout session.
The callout device is abused for handling programs that are supposed
to work on general ports and need to open the port without waiting
but are too stupid to do so.
.Pp
The
.Nm
driver also supports an initial-state and a lock-state control
device for each of the callin and the callout "data" devices.
The minor number of the initial-state device is 32 higher
than that of the corresponding data device.
The minor number of the lock-state device is 64 higher
than that of the corresponding data device.
The termios settings of a data device are copied
from those of the corresponding initial-state device
on first opens and are not inherited from previous opens.
Use
.Xr stty 1
in the normal way on the initial-state devices to program
initial termios states suitable for your setup.
.Pp
The lock termios state acts as flags to disable changing
the termios state.
E.g., to lock a flag variable such as
CRTSCTS, use
.Em "stty crtscts"
on the lock-state device.
Speeds and special characters
may be locked by setting the corresponding value in the lock-state
device to any nonzero value.
.Pp
Correct programs talking to correctly wired external devices
work with almost arbitrary initial states and almost no locking,
but other setups may benefit from changing some of the default
initial state and locking the state.
In particular, the initial states for non (POSIX) standard flags
should be set to suit the devices attached and may need to be
locked to prevent buggy programs from changing them.
E.g., CRTSCTS should be locked on for devices that support
RTS/CTS handshaking at all times and off for devices that do not
support it at all.
CLOCAL should be locked on for devices
that do not support carrier.
HUPCL may be locked off if you do not
want to hang up for some reason.
In general, very bad things happen
if something is locked to the wrong state, and things should not
be locked for devices that support more than one setting.
The
CLOCAL flag on callin ports should be locked off for logins
to avoid certain security holes, but this needs to be done by
getty if the callin port is used for anything else.
.Ss Kernel Configuration Options
The
.Em CY_PCI_FASTINTR
option should be used to avoid suboptimal interrupt handling for
PCI Cyclades boards.
The PCI BIOS must be configured with the
.Nm
interrupt not shared with any other active device
for this option to work.
This option is not the default because it is currently harmful in
certain cases where it does not work.
.Sh FILES
.\" XXX more cloning: s/d/c/g and add a ? for the card number.
.Bl -tag -width /dev/ttyic?? -compact
.It Pa /dev/ttyc??
for callin ports
.It Pa /dev/ttyic??
.It Pa /dev/ttylc??
corresponding callin initial-state and lock-state devices
.Pp
.\" XXX more cloning: s/a/c/g.  No consistency :-(.
.It Pa /dev/cuac??
for callout ports
.It Pa /dev/cuaic??
.It Pa /dev/cualc??
corresponding callout initial-state and lock-state devices
.El
.Pp
.Bl -tag -width /etc/rc.serial -compact
.It Pa /etc/rc.serial
examples of setting the initial-state and lock-state devices
.El
.Pp
The first question mark in these device names is short for the
card number
(a decimal number between 0 and 65535 inclusive).
The second question mark is short for the port number
(a letter in the range [0-9a-v]).
.Sh DIAGNOSTICS
.Bl -diag
.\" XXX back to s/sio/cy/g.
.It cy%d: silo overflow.
Problem in the interrupt handler.
.El
.Bl -diag
.It cy%d: interrupt-level buffer overflow.
Problem in the bottom half of the driver.
.El
.Bl -diag
.It cy%d: tty-level buffer overflow.
Problem in the application.
Input has arrived faster than the given module could process it
and some has been lost.
.El
.\" .Bl -diag
.\" .It sio%d: reduced fifo trigger level to %d.
.\" Attempting to avoid further silo overflows.
.\" .El
.Sh SEE ALSO
.Xr stty 1 ,
.Xr termios 4 ,
.Xr tty 4 ,
.Xr comcontrol 8 ,
.Xr pstat 8
.Sh HISTORY
The
.Nm
driver is derived from the
.Nm sio
driver and the
.Nx
.Nm
driver and is
.Ud
.Sh BUGS
Serial consoles are not implemented.