xref: /freebsd/sys/dev/ic/ns16550.h (revision 7660b554bc59a07be0431c17e0e33815818baa69)
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	from: @(#)ns16550.h	7.1 (Berkeley) 5/9/91
34  * $FreeBSD$
35  */
36 
37 /*
38  * NS8250... UART registers.
39  */
40 
41 /* 8250 registers #[0-6]. */
42 
43 #define	com_data	0	/* data register (R/W) */
44 #define	com_thr		com_data /* transmitter holding register (W) */
45 #define	com_rhr		com_data /* receiver holding register (R) */
46 
47 #define	com_ier		1	/* interrupt enable register (W) */
48 #define	IER_ERXRDY	0x1
49 #define	IER_ETXRDY	0x2
50 #define	IER_ERLS	0x4
51 #define	IER_EMSC	0x8
52 
53 #define	com_iir		2	/* interrupt identification register (R) */
54 #define	com_isr		com_iir	/* interrupt status register (R) */
55 #define	IIR_IMASK	0xf
56 #define	IIR_RXTOUT	0xc
57 #define	IIR_RLS		0x6
58 #define	IIR_RXRDY	0x4
59 #define	IIR_TXRDY	0x2
60 #define	IIR_NOPEND	0x1
61 #define	IIR_MLSC	0x0
62 #define	IIR_FIFO_MASK	0xc0	/* set if FIFOs are enabled */
63 
64 #define	com_lcr		3	/* line control register (R/W) */
65 #define	com_lctl	com_lcr
66 #define	com_cfcr	com_lcr	/* character format control register (R/W) */
67 #define	LCR_DLAB	0x80
68 #define	CFCR_DLAB	LCR_DLAB
69 #define	LCR_EFR_ENABLE	0xbf	/* magic to enable EFR on 16650 up */
70 #define	CFCR_EFR_ENABLE	LCR_EFR_ENABLE
71 #define	CFCR_SBREAK	0x40
72 #define	CFCR_PZERO	0x30
73 #define	CFCR_PONE	0x20
74 #define	CFCR_PEVEN	0x10
75 #define	CFCR_PODD	0x00
76 #define	CFCR_PENAB	0x08
77 #define	CFCR_STOPB	0x04
78 #define	CFCR_8BITS	0x03
79 #define	CFCR_7BITS	0x02
80 #define	CFCR_6BITS	0x01
81 #define	CFCR_5BITS	0x00
82 
83 #define	com_mcr		4	/* modem control register (R/W) */
84 #define	MCR_PRESCALE	0x80	/* only available on 16650 up */
85 #define	MCR_LOOPBACK	0x10
86 #define	MCR_IENABLE	0x08
87 #define	MCR_DRS		0x04
88 #define	MCR_RTS		0x02
89 #define	MCR_DTR		0x01
90 
91 #define	com_lsr		5	/* line status register (R/W) */
92 #define	LSR_RCV_FIFO	0x80
93 #define	LSR_TSRE	0x40
94 #define	LSR_TXRDY	0x20
95 #define	LSR_BI		0x10
96 #define	LSR_FE		0x08
97 #define	LSR_PE		0x04
98 #define	LSR_OE		0x02
99 #define	LSR_RXRDY	0x01
100 #define	LSR_RCV_MASK	0x1f
101 
102 #define	com_msr		6	/* modem status register (R/W) */
103 #define	MSR_DCD		0x80
104 #define	MSR_RI		0x40
105 #define	MSR_DSR		0x20
106 #define	MSR_CTS		0x10
107 #define	MSR_DDCD	0x08
108 #define	MSR_TERI	0x04
109 #define	MSR_DDSR	0x02
110 #define	MSR_DCTS	0x01
111 
112 /* 8250 multiplexed registers #[0-1].  Access enabled by LCR[7]. */
113 #define	com_dll		0	/* divisor latch low (R/W) */
114 #define	com_dlbl	com_dll
115 #define	com_dlm		1	/* divisor latch high (R/W) */
116 #define	com_dlbh	com_dlm
117 
118 /* 16450 register #7.  Not multiplexed. */
119 #define	com_scr		7	/* scratch register (R/W) */
120 
121 /* 16550 register #2.  Not multiplexed. */
122 #define	com_fcr		2	/* FIFO control register (W) */
123 #define	com_fifo	com_fcr
124 #define	FIFO_ENABLE	0x01
125 #define	FIFO_RCV_RST	0x02
126 #define	FIFO_XMT_RST	0x04
127 #define	FIFO_DMA_MODE	0x08
128 #define	FIFO_RX_LOW	0x00
129 #define	FIFO_RX_MEDL	0x40
130 #define	FIFO_RX_MEDH	0x80
131 #define	FIFO_RX_HIGH	0xc0
132 
133 /* 16650 registers #2,[4-7].  Access enabled by LCR_EFR_ENABLE. */
134 
135 #define	com_efr		2	/* enhanced features register (R/W) */
136 #define	EFR_AUTOCTS	0x80
137 #define	EFR_AUTORTS	0x40
138 #define	EFR_EFE		0x10	/* enhanced functions enable */
139 
140 #define	com_xon1	4	/* XON 1 character (R/W) */
141 #define	com_xon2	5	/* XON 2 character (R/W) */
142 #define	com_xoff1	6	/* XOFF 1 character (R/W) */
143 #define	com_xoff2	7	/* XOFF 2 character (R/W) */
144 
145 /* 16950 register #1.  Access enabled by ACR[7].  Also requires !LCR[7]. */
146 #define	com_asr		1	/* additional status register (R[0-7]/W[0-1]) */
147 
148 /* 16950 register #3.  R/W access enabled by ACR[7]. */
149 #define	com_rfl		3	/* receiver fifo level (R) */
150 
151 /*
152  * 16950 register #4.  Access enabled by ACR[7].  Also requires
153  * !LCR_EFR_ENABLE.
154  */
155 #define	com_tfl		4	/* transmitter fifo level (R) */
156 
157 /*
158  * 16950 register #5.  Accessible if !LCR_EFR_ENABLE.  Read access also
159  * requires ACR[6].
160  */
161 #define	com_icr		5	/* index control register (R/W) */
162 
163 /*
164  * 16950 register #7.  It is the same as com_scr except it has a different
165  * abbreviation in the manufacturer's data sheet and it also serves as an
166  * index into the Indexed Control register set.
167  */
168 #define	com_spr		com_scr	/* scratch pad (and index) register (R/W) */
169 
170 /*
171  * 16950 indexed control registers #[0-0x13].  Access is via index in SPR,
172  * data in ICR (if ICR is accessible).
173  */
174 
175 #define	com_acr		0	/* additional control register (R/W) */
176 #define	ACR_ASE		0x80	/* ASR/RFL/TFL enable */
177 #define	ACR_ICRE	0x40	/* ICR enable */
178 #define	ACR_TLE		0x20	/* TTL/RTL enable */
179 
180 #define	com_cpr		1	/* clock prescaler register (R/W) */
181 #define	com_tcr		2	/* times clock register (R/W) */
182 #define	com_ttl		4	/* transmitter trigger level (R/W) */
183 #define	com_rtl		5	/* receiver trigger level (R/W) */
184 /* ... */
185 
186 #ifdef PC98
187 /* Hardware extension mode register for RSB-2000/3000. */
188 #define	com_emr		com_msr
189 #define	EMR_EXBUFF	0x04
190 #define	EMR_CTSFLW	0x08
191 #define	EMR_DSRFLW	0x10
192 #define	EMR_RTSFLW	0x20
193 #define	EMR_DTRFLW	0x40
194 #define	EMR_EFMODE	0x80
195 #endif
196