console.c revision 266337 
1/*-
2 * Copyright (c) 2012 Ganbold Tsagaankhuu <ganbold@freebsd.org>
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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27/* Simple UART console driver for Allwinner A10 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: stable/10/sys/arm/allwinner/console.c 266337 2014-05-17 18:53:36Z ian $");
31
32#include <sys/types.h>
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/cons.h>
36#include <sys/consio.h>
37#include <sys/kernel.h>
38
39#ifndef	A10_UART_BASE
40#define	A10_UART_BASE	0xe1c28000 	/* UART0 */
41#endif
42
43#define	REG_SHIFT	2
44
45#define	UART_DLL	0	/* Out: Divisor Latch Low */
46#define	UART_DLM	1	/* Out: Divisor Latch High */
47#define	UART_FCR	2	/* Out: FIFO Control Register */
48#define	UART_LCR	3	/* Out: Line Control Register */
49#define	UART_MCR	4	/* Out: Modem Control Register */
50#define	UART_LSR	5	/* In:  Line Status Register */
51#define	UART_LSR_THRE	0x20	/* Transmit-hold-register empty */
52#define	UART_LSR_DR	0x01	/* Receiver data ready */
53#define	UART_MSR	6	/* In:  Modem Status Register */
54#define	UART_SCR	7	/* I/O: Scratch Register */
55
56static uint32_t
57uart_getreg(uint32_t *bas)
58{
59	return *((volatile uint32_t *)(bas)) & 0xff;
60}
61
62static void
63uart_setreg(uint32_t *bas, uint32_t val)
64{
65	*((volatile uint32_t *)(bas)) = val;
66}
67
68static int
69ub_getc(void)
70{
71	while ((uart_getreg((uint32_t *)(A10_UART_BASE +
72	    (UART_LSR << REG_SHIFT))) & UART_LSR_DR) == 0);
73		__asm __volatile("nop");
74
75	return (uart_getreg((uint32_t *)A10_UART_BASE) & 0xff);
76}
77
78static void
79ub_putc(unsigned char c)
80{
81	if (c == '\n')
82		ub_putc('\r');
83
84	while ((uart_getreg((uint32_t *)(A10_UART_BASE +
85	    (UART_LSR << REG_SHIFT))) & UART_LSR_THRE) == 0)
86		__asm __volatile("nop");
87
88	uart_setreg((uint32_t *)A10_UART_BASE, c);
89}
90
91static cn_probe_t	uart_cnprobe;
92static cn_init_t	uart_cninit;
93static cn_term_t	uart_cnterm;
94static cn_getc_t	uart_cngetc;
95static cn_putc_t	uart_cnputc;
96static cn_grab_t	uart_cngrab;
97static cn_ungrab_t	uart_cnungrab;
98
99static void
100uart_cngrab(struct consdev *cp)
101{
102}
103
104static void
105uart_cnungrab(struct consdev *cp)
106{
107}
108
109
110static void
111uart_cnprobe(struct consdev *cp)
112{
113	sprintf(cp->cn_name, "uart");
114	cp->cn_pri = CN_NORMAL;
115}
116
117static void
118uart_cninit(struct consdev *cp)
119{
120	uart_setreg((uint32_t *)(A10_UART_BASE +
121	    (UART_FCR << REG_SHIFT)), 0x06);
122}
123
124void
125uart_cnputc(struct consdev *cp, int c)
126{
127	ub_putc(c);
128}
129
130int
131uart_cngetc(struct consdev * cp)
132{
133	return ub_getc();
134}
135
136static void
137uart_cnterm(struct consdev * cp)
138{
139}
140
141CONSOLE_DRIVER(uart);
142
143