xref: /freebsd/sys/dev/uart/uart.h (revision ba2336d3044c681462224c12879ecc8f659be54a)
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 	void	*driver1;
44 	u_int	chan;
45 	u_int	rclk;
46 	u_int	regshft;
47 	u_int	regiowidth;
48 	u_int	busy_detect;
49 	u_int	rclk_guess;/* if rclk == 0, use baud + divisor to compute rclk */
50 };
51 
52 #define	uart_regofs(bas, reg)		((reg) << (bas)->regshft)
53 #define	uart_regiowidth(bas)		((bas)->regiowidth)
54 
55 static inline uint32_t
uart_getreg(struct uart_bas * bas,int reg)56 uart_getreg(struct uart_bas *bas, int reg)
57 {
58 	uint32_t ret;
59 
60 	switch (uart_regiowidth(bas)) {
61 #if !defined(__i386__)
62 	case 8:
63 		ret = bus_space_read_8(bas->bst, bas->bsh, uart_regofs(bas, reg));
64 		break;
65 #endif
66 	case 4:
67 		ret = bus_space_read_4(bas->bst, bas->bsh, uart_regofs(bas, reg));
68 		break;
69 	case 2:
70 		ret = bus_space_read_2(bas->bst, bas->bsh, uart_regofs(bas, reg));
71 		break;
72 	default:
73 		ret = bus_space_read_1(bas->bst, bas->bsh, uart_regofs(bas, reg));
74 		break;
75 	}
76 
77 	return (ret);
78 }
79 
80 static inline void
uart_setreg(struct uart_bas * bas,int reg,uint32_t value)81 uart_setreg(struct uart_bas *bas, int reg, uint32_t value)
82 {
83 
84 	switch (uart_regiowidth(bas)) {
85 #if !defined(__i386__)
86 	case 8:
87 		bus_space_write_8(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
88 		break;
89 #endif
90 	case 4:
91 		bus_space_write_4(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
92 		break;
93 	case 2:
94 		bus_space_write_2(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
95 		break;
96 	default:
97 		bus_space_write_1(bas->bst, bas->bsh, uart_regofs(bas, reg), value);
98 		break;
99 	}
100 }
101 
102 /*
103  * XXX we don't know the length of the bus space address range in use by
104  * the UART. Since barriers don't use the length field currently, we put
105  * a zero there for now.
106  */
107 #define uart_barrier(bas)		\
108 	bus_space_barrier((bas)->bst, (bas)->bsh, 0, 0,		\
109 	    BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE)
110 
111 /*
112  * UART device classes.
113  */
114 struct uart_class;
115 
116 SET_DECLARE(uart_class_set, struct uart_class);
117 
118 extern struct uart_class uart_ns8250_class __attribute__((weak));
119 extern struct uart_class uart_quicc_class __attribute__((weak));
120 extern struct uart_class uart_z8530_class __attribute__((weak));
121 
122 /*
123  * Device flags.
124  */
125 #define	UART_FLAGS_CONSOLE(f)		((f) & 0x10)
126 #define	UART_FLAGS_DBGPORT(f)		((f) & 0x80)
127 #define	UART_FLAGS_FCR_RX_LOW(f)	((f) & 0x100)
128 #define	UART_FLAGS_FCR_RX_MEDL(f)	((f) & 0x200)
129 #define	UART_FLAGS_FCR_RX_MEDH(f)	((f) & 0x400)
130 #define	UART_FLAGS_FCR_RX_HIGH(f)	((f) & 0x800)
131 
132 /*
133  * Data parity values (magical numbers related to ns8250).
134  */
135 #define	UART_PARITY_NONE		0
136 #define	UART_PARITY_ODD			1
137 #define	UART_PARITY_EVEN		3
138 #define	UART_PARITY_MARK		5
139 #define	UART_PARITY_SPACE		7
140 
141 #endif /* _DEV_UART_H_ */
142