1.\" $NetBSD: magma.4,v 1.10 2008/07/02 10:16:20 plunky Exp $ 2.\" 3.\" Copyright (c) 1998 Iain Hibbert 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.Dd April 21, 1998 27.Dt MAGMA 4 sparc 28.Sh NAME 29.Nm magma 30.Nd 31Magma Sp Serial/Parallel board device driver 32.Sh SYNOPSIS 33.Cd "magma* at sbus? slot ? offset ?" 34.Cd "mtty* at magma?" 35.Cd "mbpp* at magma?" 36.Sh DESCRIPTION 37The 38.Nm 39driver provides an interface to Magma LC2+1Sp, 2+1Sp, 4+1Sp, 8+2Sp, 404Sp, 8Sp, 12Sp, 16Sp, 1P and 2P boards. 41These boards are based around the Cirrus Logic CD1400 serial/parallel 42communications engine and the Cirrus Logic CD1190 parallel 43communications engine. 44.Pp 45The device minor numbers for this driver are encoded as follows: 46.Pp 47.Bd -literal 48 +---+---+---+---+---+---+---+---+ 49 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 50 +---+---+---+---+---+---+---+---+ 51 | | | | | | | | 52 | | | | +---+---+---+---\*[Gt] port number 53 | | | | 54 | | | +-------------------\*[Gt] dial-out (on tty ports) 55 | | | 56 | | +-----------------------\*[Gt] unused 57 | | 58 +---+---------------------------\*[Gt] card number 59.Ed 60.Pp 61Up to four cards are supported in the system. 62.Pp 63All tty ports have full automatic hardware (RTS/CTS) flow control available 64and a 12 byte FIFO on the chip in each direction so errors should be minimal. 65.Sh FILES 66.Bl -tag -width /dev/bpp[0-3][0-1] -compact 67.It Pa /dev/tty[0-3][0-a] 68Serial ports 69.It Pa /dev/bpp[0-3][0-1] 70Parallel ports 71.El 72.Sh DIAGNOSTICS 73.Bl -diag 74.It "mtty%d%x: ring buffer overflow" 75Incoming characters have been discarded due to a buffer overflow. 76This is caused by the process in control of the device not reading 77characters fast enough. 78.Pp 79If need be you can make the ring buffer bigger by changing the 80.Dv MAGMA_RBUF_SIZE 81#define to something bigger, but it should be a multiple 82of two. 83.It "mtty%d%x: fifo overflow" 84Incoming characters have been discarded due to a CD1400 channel overrun. 85This is caused by interrupts not being serviced sufficiently quickly 86to prevent the 12 byte receive FIFO on a serial channel from overflowing. 87.Pp 88Reducing the value of either the 89.Dv MTTY_RX_FIFO_THRESHOLD 90or 91.Dv MTTY_RX_DTR_THRESHOLD 92#define's to something smaller may help slow machines avoid this problem. 93.El 94.Sh SEE ALSO 95.Xr read 2 , 96.Xr termios 4 , 97.Xr tty 4 98.Sh HISTORY 99The driver was loosely based upon the 100.Xr cy 4 101Cyclades Cyclom device driver written 102by Andrew Herbert and Timo Rossi. 103.Sh AUTHORS 104The driver was written by 105.An Iain Hibbert . 106.Sh TO DO 107CD1190 parallel support. 108.Pp 109.Qq bpp 110input. 111.Pp 112Dial-out (cua) devices are not yet supported. 113.Pp 114.Qq mdmbuf 115is unsupported (see 116.Xr tty 4 117and 118.Xr termios 4 ) . 119.Pp 120Automatic XON/XOFF handshaking could be implemented fairly easily. 121.Pp 122It would be good if the tty port waited for the FIFO to empty before allowing 123a close, so that I could turn off the channel interrupts at that time. 124It can be done. 125