xref: /freebsd/sys/dev/uart/uart.h (revision 0aa4a9fc859fd43343e2d7b5094a50d1ca0948eb)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2003 Marcel Moolenaar
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef _DEV_UART_H_
30 #define _DEV_UART_H_
31 
32 #include <sys/linker_set.h>
33 
34 /*
35  * Bus access structure. This structure holds the minimum information needed
36  * to access the UART. The rclk field, although not important to actually
37  * access the UART, is important for baudrate programming, delay loops and
38  * other timing related computations.
39  */
40 struct uart_bas {
41 	bus_space_tag_t bst;
42 	bus_space_handle_t bsh;
43 	u_int	chan;
44 	u_int	rclk;
45 	u_int	regshft;
46 	u_int	regiowidth;
47 	u_int	busy_detect;
48 	u_int	rclk_guess;/* if rclk == 0, use baud + divisor to compute rclk */
49 };
50 
51 #define	uart_regofs(bas, reg)		((reg) << (bas)->regshft)
52 #define	uart_regiowidth(bas)		((bas)->regiowidth)
53 
54 static inline uint32_t
55 uart_getreg(struct uart_bas *bas, int reg)
56 {
57 	uint32_t ret;
58 
59 	switch (uart_regiowidth(bas)) {
60 #if !defined(__i386__)
61 	case 8:
62 		ret = bus_space_read_8(bas->bst, bas->bsh, uart_regofs(bas, reg));
63 		break;
64 #endif
65 	case 4:
66 		ret = bus_space_read_4(bas->bst, bas->bsh, uart_regofs(bas, reg));
67 		break;
68 	case 2:
69 		ret = bus_space_read_2(bas->bst, bas->bsh, uart_regofs(bas, reg));
70 		break;
71 	default:
72 		ret = bus_space_read_1(bas->bst, bas->bsh, uart_regofs(bas, reg));
73 		break;
74 	}
75 
76 	return (ret);
77 }
78 
79 static inline void
80 uart_setreg(struct uart_bas *bas, int reg, uint32_t value)
81 {
82 
83 	switch (uart_regiowidth(bas)) {
84 #if !defined(__i386__)
85 	case 8:
86 		bus_space_write_8(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
87 		break;
88 #endif
89 	case 4:
90 		bus_space_write_4(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
91 		break;
92 	case 2:
93 		bus_space_write_2(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
94 		break;
95 	default:
96 		bus_space_write_1(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
97 		break;
98 	}
99 }
100 
101 /*
102  * XXX we don't know the length of the bus space address range in use by
103  * the UART. Since barriers don't use the length field currently, we put
104  * a zero there for now.
105  */
106 #define uart_barrier(bas)		\
107 	bus_space_barrier((bas)->bst, (bas)->bsh, 0, 0,		\
108 	    BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE)
109 
110 /*
111  * UART device classes.
112  */
113 struct uart_class;
114 
115 SET_DECLARE(uart_class_set, struct uart_class);
116 
117 extern struct uart_class uart_ns8250_class __attribute__((weak));
118 extern struct uart_class uart_quicc_class __attribute__((weak));
119 extern struct uart_class uart_z8530_class __attribute__((weak));
120 
121 /*
122  * Device flags.
123  */
124 #define	UART_FLAGS_CONSOLE(f)		((f) & 0x10)
125 #define	UART_FLAGS_DBGPORT(f)		((f) & 0x80)
126 #define	UART_FLAGS_FCR_RX_LOW(f)	((f) & 0x100)
127 #define	UART_FLAGS_FCR_RX_MEDL(f)	((f) & 0x200)
128 #define	UART_FLAGS_FCR_RX_MEDH(f)	((f) & 0x400)
129 #define	UART_FLAGS_FCR_RX_HIGH(f)	((f) & 0x800)
130 
131 /*
132  * Data parity values (magical numbers related to ns8250).
133  */
134 #define	UART_PARITY_NONE		0
135 #define	UART_PARITY_ODD			1
136 #define	UART_PARITY_EVEN		3
137 #define	UART_PARITY_MARK		5
138 #define	UART_PARITY_SPACE		7
139 
140 #endif /* _DEV_UART_H_ */
141