xref: /freebsd/sys/dev/ic/ns16550.h (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
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  *	from: @(#)ns16550.h	7.1 (Berkeley) 5/9/91
30  * $FreeBSD$
31  */
32 
33 /*
34  * NS8250... UART registers.
35  */
36 
37 /* 8250 registers #[0-6]. */
38 
39 #define	com_data	0	/* data register (R/W) */
40 #define	com_thr		com_data /* transmitter holding register (W) */
41 #define	com_rhr		com_data /* receiver holding register (R) */
42 
43 #define	com_ier		1	/* interrupt enable register (W) */
44 #define	IER_ERXRDY	0x1
45 #define	IER_ETXRDY	0x2
46 #define	IER_ERLS	0x4
47 #define	IER_EMSC	0x8
48 
49 #define	com_iir		2	/* interrupt identification register (R) */
50 #define	com_isr		com_iir	/* interrupt status register (R) */
51 #define	IIR_IMASK	0xf
52 #define	IIR_RXTOUT	0xc
53 #define	IIR_RLS		0x6
54 #define	IIR_RXRDY	0x4
55 #define	IIR_TXRDY	0x2
56 #define	IIR_NOPEND	0x1
57 #define	IIR_MLSC	0x0
58 #define	IIR_FIFO_MASK	0xc0	/* set if FIFOs are enabled */
59 
60 #define	com_lcr		3	/* line control register (R/W) */
61 #define	com_lctl	com_lcr
62 #define	com_cfcr	com_lcr	/* character format control register (R/W) */
63 #define	LCR_DLAB	0x80
64 #define	CFCR_DLAB	LCR_DLAB
65 #define	LCR_EFR_ENABLE	0xbf	/* magic to enable EFR on 16650 up */
66 #define	CFCR_EFR_ENABLE	LCR_EFR_ENABLE
67 #define	CFCR_SBREAK	0x40
68 #define	CFCR_PZERO	0x30
69 #define	CFCR_PONE	0x20
70 #define	CFCR_PEVEN	0x10
71 #define	CFCR_PODD	0x00
72 #define	CFCR_PENAB	0x08
73 #define	CFCR_STOPB	0x04
74 #define	CFCR_8BITS	0x03
75 #define	CFCR_7BITS	0x02
76 #define	CFCR_6BITS	0x01
77 #define	CFCR_5BITS	0x00
78 
79 #define	com_mcr		4	/* modem control register (R/W) */
80 #define	MCR_PRESCALE	0x80	/* only available on 16650 up */
81 #define	MCR_LOOPBACK	0x10
82 #define	MCR_IENABLE	0x08
83 #define	MCR_DRS		0x04
84 #define	MCR_RTS		0x02
85 #define	MCR_DTR		0x01
86 
87 #define	com_lsr		5	/* line status register (R/W) */
88 #define	LSR_RCV_FIFO	0x80
89 #define	LSR_TSRE	0x40
90 #define	LSR_TXRDY	0x20
91 #define	LSR_BI		0x10
92 #define	LSR_FE		0x08
93 #define	LSR_PE		0x04
94 #define	LSR_OE		0x02
95 #define	LSR_RXRDY	0x01
96 #define	LSR_RCV_MASK	0x1f
97 
98 #define	com_msr		6	/* modem status register (R/W) */
99 #define	MSR_DCD		0x80
100 #define	MSR_RI		0x40
101 #define	MSR_DSR		0x20
102 #define	MSR_CTS		0x10
103 #define	MSR_DDCD	0x08
104 #define	MSR_TERI	0x04
105 #define	MSR_DDSR	0x02
106 #define	MSR_DCTS	0x01
107 
108 /* 8250 multiplexed registers #[0-1].  Access enabled by LCR[7]. */
109 #define	com_dll		0	/* divisor latch low (R/W) */
110 #define	com_dlbl	com_dll
111 #define	com_dlm		1	/* divisor latch high (R/W) */
112 #define	com_dlbh	com_dlm
113 
114 /* 16450 register #7.  Not multiplexed. */
115 #define	com_scr		7	/* scratch register (R/W) */
116 
117 /* 16550 register #2.  Not multiplexed. */
118 #define	com_fcr		2	/* FIFO control register (W) */
119 #define	com_fifo	com_fcr
120 #define	FIFO_ENABLE	0x01
121 #define	FIFO_RCV_RST	0x02
122 #define	FIFO_XMT_RST	0x04
123 #define	FIFO_DMA_MODE	0x08
124 #define	FIFO_RX_LOW	0x00
125 #define	FIFO_RX_MEDL	0x40
126 #define	FIFO_RX_MEDH	0x80
127 #define	FIFO_RX_HIGH	0xc0
128 
129 /* 16650 registers #2,[4-7].  Access enabled by LCR_EFR_ENABLE. */
130 
131 #define	com_efr		2	/* enhanced features register (R/W) */
132 #define	EFR_AUTOCTS	0x80
133 #define	EFR_AUTORTS	0x40
134 #define	EFR_EFE		0x10	/* enhanced functions enable */
135 
136 #define	com_xon1	4	/* XON 1 character (R/W) */
137 #define	com_xon2	5	/* XON 2 character (R/W) */
138 #define	com_xoff1	6	/* XOFF 1 character (R/W) */
139 #define	com_xoff2	7	/* XOFF 2 character (R/W) */
140 
141 /* 16950 register #1.  Access enabled by ACR[7].  Also requires !LCR[7]. */
142 #define	com_asr		1	/* additional status register (R[0-7]/W[0-1]) */
143 
144 /* 16950 register #3.  R/W access enabled by ACR[7]. */
145 #define	com_rfl		3	/* receiver fifo level (R) */
146 
147 /*
148  * 16950 register #4.  Access enabled by ACR[7].  Also requires
149  * !LCR_EFR_ENABLE.
150  */
151 #define	com_tfl		4	/* transmitter fifo level (R) */
152 
153 /*
154  * 16950 register #5.  Accessible if !LCR_EFR_ENABLE.  Read access also
155  * requires ACR[6].
156  */
157 #define	com_icr		5	/* index control register (R/W) */
158 
159 /*
160  * 16950 register #7.  It is the same as com_scr except it has a different
161  * abbreviation in the manufacturer's data sheet and it also serves as an
162  * index into the Indexed Control register set.
163  */
164 #define	com_spr		com_scr	/* scratch pad (and index) register (R/W) */
165 
166 /*
167  * 16950 indexed control registers #[0-0x13].  Access is via index in SPR,
168  * data in ICR (if ICR is accessible).
169  */
170 
171 #define	com_acr		0	/* additional control register (R/W) */
172 #define	ACR_ASE		0x80	/* ASR/RFL/TFL enable */
173 #define	ACR_ICRE	0x40	/* ICR enable */
174 #define	ACR_TLE		0x20	/* TTL/RTL enable */
175 
176 #define	com_cpr		1	/* clock prescaler register (R/W) */
177 #define	com_tcr		2	/* times clock register (R/W) */
178 #define	com_ttl		4	/* transmitter trigger level (R/W) */
179 #define	com_rtl		5	/* receiver trigger level (R/W) */
180 /* ... */
181 
182 #ifdef PC98
183 /* Hardware extension mode register for RSB-2000/3000. */
184 #define	com_emr		com_msr
185 #define	EMR_EXBUFF	0x04
186 #define	EMR_CTSFLW	0x08
187 #define	EMR_DSRFLW	0x10
188 #define	EMR_RTSFLW	0x20
189 #define	EMR_DTRFLW	0x40
190 #define	EMR_EFMODE	0x80
191 #endif
192