xref: /trueos/sys/dev/ic/i8251.h (revision 598da5ab172a68da03b4ef0ea269980d585972ef)
1 /*-
2  * Copyright (c) 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 /*
33  * modified for PC9801 by M.Ishii
34  *			Kyoto University Microcomputer Club (KMC)
35  *
36  * modified for 8251(FIFO) by Seigo TANIMURA <tanimura@FreeBSD.org>
37  */
38 
39 /* i8251 mode register */
40 #define	MOD8251_5BITS	0x00
41 #define	MOD8251_6BITS	0x04
42 #define	MOD8251_7BITS	0x08
43 #define	MOD8251_8BITS	0x0c
44 #define	MOD8251_PENAB	0x10	/* parity enable */
45 #define	MOD8251_PEVEN	0x20	/* parity even */
46 #define	MOD8251_STOP1	0x40	/* 1 stop bit */
47 #define	MOD8251_STOP15	0x80	/* 1.5 stop bit */
48 #define	MOD8251_STOP2	0xc0	/* 2 stop bit */
49 #define	MOD8251_CLKx1	0x01	/* x1 */
50 #define	MOD8251_CLKx16	0x02	/* x16 */
51 #define	MOD8251_CLKx64	0x03	/* x64 */
52 
53 /* i8251 command register */
54 #define	CMD8251_TxEN	0x01	/* transmit enable */
55 #define	CMD8251_DTR	0x02	/* assert DTR */
56 #define	CMD8251_RxEN	0x04	/* receive enable */
57 #define	CMD8251_SBRK	0x08	/* send break */
58 #define	CMD8251_ER	0x10	/* error reset */
59 #define	CMD8251_RTS	0x20	/* assert RTS */
60 #define	CMD8251_RESET	0x40	/* internal reset */
61 #define	CMD8251_EH	0x80	/* enter hunt mode */
62 
63 /* i8251 status register */
64 #define	STS8251_TxRDY	0x01	/* transmit READY */
65 #define	STS8251_RxRDY	0x02	/* data exists in receive buffer */
66 #define	STS8251_TxEMP	0x04	/* transmit buffer EMPTY */
67 #define	STS8251_PE	0x08	/* perity error */
68 #define	STS8251_OE	0x10	/* overrun error */
69 #define	STS8251_FE	0x20	/* framing error */
70 #define	STS8251_BI	0x40	/* break detect */
71 #define	STS8251_DSR	0x80	/* DSR is asserted */
72 
73 /* i8251F line status register */
74 #define	FLSR_TxEMP	0x01	/* transmit buffer EMPTY */
75 #define	FLSR_TxRDY	0x02	/* transmit READY */
76 #define	FLSR_RxRDY	0x04	/* data exists in receive buffer */
77 #define	FLSR_OE		0x10	/* overrun error */
78 #define	FLSR_PE		0x20	/* perity error */
79 #define	FLSR_BI		0x80	/* break detect */
80 
81 /* i8251F modem status register */
82 #define	MSR_DCD		0x80	/* Current Data Carrier Detect */
83 #define	MSR_RI		0x40	/* Current Ring Indicator */
84 #define	MSR_DSR		0x20	/* Current Data Set Ready */
85 #define	MSR_CTS		0x10	/* Current Clear to Send */
86 #define	MSR_DDCD	0x08	/* DCD has changed state */
87 #define	MSR_TERI	0x04	/* RI has toggled low to high */
88 #define	MSR_DDSR	0x02	/* DSR has changed state */
89 #define	MSR_DCTS	0x01	/* CTS has changed state */
90 
91 /* i8251F interrupt identification register */
92 #define	IIR_FIFO_CK1	0x40
93 #define	IIR_FIFO_CK2	0x20
94 #define	IIR_IMASK	0x0f
95 #define	IIR_RXTOUT	0x0c	/* Receiver timeout */
96 #define	IIR_RLS		0x06	/* Line status change */
97 #define	IIR_RXRDY	0x04	/* Receiver ready */
98 #define	IIR_TXRDY	0x02	/* Transmitter ready */
99 #define	IIR_NOPEND	0x01	/* Transmitter ready */
100 #define	IIR_MLSC	0x00	/* Modem status */
101 
102 /* i8251F fifo control register */
103 #define	FIFO_ENABLE	0x01	/* Turn the FIFO on */
104 #define	FIFO_RCV_RST	0x02	/* Reset RX FIFO */
105 #define	FIFO_XMT_RST	0x04	/* Reset TX FIFO */
106 #define	FIFO_LSR_EN	0x08
107 #define	FIFO_MSR_EN	0x10
108 #define	FIFO_TRIGGER_1	0x00	/* Trigger RXRDY intr on 1 character */
109 #define	FIFO_TRIGGER_4	0x40	/* ibid 4 */
110 #define	FIFO_TRIGGER_8	0x80	/* ibid 8 */
111 #define	FIFO_TRIGGER_14	0xc0	/* ibid 14 */
112