summaryrefslogtreecommitdiff
path: root/drivers/serial/mcfuart.c
blob: e04fc298d960d8d338140db468a1022b6342753d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/*
 * (C) Copyright 2004-2007 Freescale Semiconductor, Inc.
 * TsiChung Liew, Tsi-Chung.Liew@freescale.com.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 */

/*
 * Minimal serial functions needed to use one of the uart ports
 * as serial console interface.
 */

#include <common.h>

#include <asm/immap.h>
#include <asm/uart.h>

DECLARE_GLOBAL_DATA_PTR;

extern void uart_port_conf(void);

int serial_init(void)
{
	volatile uart_t *uart;
	u32 counter;

	uart = (volatile uart_t *)(CONFIG_SYS_UART_BASE);

	uart_port_conf();

	/* write to SICR: SIM2 = uart mode,dcd does not affect rx */
	uart->ucr = UART_UCR_RESET_RX;
	uart->ucr = UART_UCR_RESET_TX;
	uart->ucr = UART_UCR_RESET_ERROR;
	uart->ucr = UART_UCR_RESET_MR;
	__asm__("nop");

	uart->uimr = 0;

	/* write to CSR: RX/TX baud rate from timers */
	uart->ucsr = (UART_UCSR_RCS_SYS_CLK | UART_UCSR_TCS_SYS_CLK);

	uart->umr = (UART_UMR_BC_8 | UART_UMR_PM_NONE);
	uart->umr = UART_UMR_SB_STOP_BITS_1;

	/* Setting up BaudRate */
	counter = (u32) ((gd->bus_clk / 32) + (gd->baudrate / 2));
	counter = counter / gd->baudrate;

	/* write to CTUR: divide counter upper byte */
	uart->ubg1 = (u8) ((counter & 0xff00) >> 8);
	/* write to CTLR: divide counter lower byte */
	uart->ubg2 = (u8) (counter & 0x00ff);

	uart->ucr = (UART_UCR_RX_ENABLED | UART_UCR_TX_ENABLED);

	return (0);
}

void serial_putc(const char c)
{
	volatile uart_t *uart = (volatile uart_t *)(CONFIG_SYS_UART_BASE);

	if (c == '\n')
		serial_putc('\r');

	/* Wait for last character to go. */
	while (!(uart->usr & UART_USR_TXRDY)) ;

	uart->utb = c;
}

void serial_puts(const char *s)
{
	while (*s) {
		serial_putc(*s++);
	}
}

int serial_getc(void)
{
	volatile uart_t *uart = (volatile uart_t *)(CONFIG_SYS_UART_BASE);

	/* Wait for a character to arrive. */
	while (!(uart->usr & UART_USR_RXRDY)) ;
	return uart->urb;
}

int serial_tstc(void)
{
	volatile uart_t *uart = (volatile uart_t *)(CONFIG_SYS_UART_BASE);

	return (uart->usr & UART_USR_RXRDY);
}

void serial_setbrg(void)
{
	volatile uart_t *uart = (volatile uart_t *)(CONFIG_SYS_UART_BASE);
	u32 counter;

	counter = ((gd->bus_clk / gd->baudrate)) >> 5;
	counter++;

	/* write to CTUR: divide counter upper byte */
	uart->ubg1 = ((counter & 0xff00) >> 8);
	/* write to CTLR: divide counter lower byte */
	uart->ubg2 = (counter & 0x00ff);

	uart->ucr = UART_UCR_RESET_RX;
	uart->ucr = UART_UCR_RESET_TX;

	uart->ucr = UART_UCR_RX_ENABLED | UART_UCR_TX_ENABLED;
}