board_bwct.c revision 185539 
1/*-
2 * Copyright (c) 2005-2008 Olivier Houchard.  All rights reserved.
3 * Copyright (c) 2005-2008 Warner Losh.  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 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 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#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/arm/at91/board_bwct.c 185539 2008-12-02 02:26:15Z peter $");
29#include <sys/param.h>
30#include <sys/systm.h>
31
32#include <arm/at91/at91board.h>
33#include <arm/at91/at91rm92reg.h>
34#include <arm/at91/at91_piovar.h>
35#include <arm/at91/at91_pio_rm9200.h>
36
37long
38board_init(void)
39{
40	/*
41	 * Since the USART supports RS-485 multidrop mode, it allows the
42	 * TX pins to float.  However, for RS-232 operations, we don't want
43	 * these pins to float.  Instead, they should be pulled up to avoid
44	 * mismatches.  Linux does something similar when it configures the
45	 * TX lines.  This implies that we also allow the RX lines to float
46	 * rather than be in the state they are left in by the boot loader.
47	 * Since they are input pins, I think that this is the right thing
48	 * to do.
49	 */
50
51	/* PIOA's A periph: Turn USART 0 and 2's TX/RX pins */
52	at91_pio_use_periph_a(AT91RM92_PIOA_BASE,
53	    AT91C_PA18_RXD0 | AT91C_PA22_RXD2, 0);
54	at91_pio_use_periph_a(AT91RM92_PIOA_BASE,
55	    AT91C_PA17_TXD0 | AT91C_PA23_TXD2, 1);
56	/* PIOA's B periph: Turn USART 3's TX/RX pins */
57	at91_pio_use_periph_b(AT91RM92_PIOA_BASE, AT91C_PA6_RXD3, 0);
58	at91_pio_use_periph_b(AT91RM92_PIOA_BASE, AT91C_PA5_TXD3, 1);
59	/* PIOB's A periph: Turn USART 1's TX/RX pins */
60	at91_pio_use_periph_a(AT91RM92_PIOB_BASE, AT91C_PB21_RXD1, 0);
61	at91_pio_use_periph_a(AT91RM92_PIOB_BASE, AT91C_PB20_TXD1, 1);
62
63	/* Pin assignment */
64
65	return (at91_ramsize());
66}
67