xref: /rk3399_rockchip-uboot/drivers/serial/mcfuart.c (revision 2bd806fe4fc23958b8f78778199e7a6e3f8f6ad5)
1*2bd806feSTsiChungLiew /*
2*2bd806feSTsiChungLiew  * (C) Copyright 2004-2007 Freescale Semiconductor, Inc.
3*2bd806feSTsiChungLiew  * TsiChung Liew, Tsi-Chung.Liew@freescale.com.
4*2bd806feSTsiChungLiew  *
5*2bd806feSTsiChungLiew  * See file CREDITS for list of people who contributed to this
6*2bd806feSTsiChungLiew  * project.
7*2bd806feSTsiChungLiew  *
8*2bd806feSTsiChungLiew  * This program is free software; you can redistribute it and/or
9*2bd806feSTsiChungLiew  * modify it under the terms of the GNU General Public License as
10*2bd806feSTsiChungLiew  * published by the Free Software Foundation; either version 2 of
11*2bd806feSTsiChungLiew  * the License, or (at your option) any later version.
12*2bd806feSTsiChungLiew  *
13*2bd806feSTsiChungLiew  * This program is distributed in the hope that it will be useful,
14*2bd806feSTsiChungLiew  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15*2bd806feSTsiChungLiew  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16*2bd806feSTsiChungLiew  * GNU General Public License for more details.
17*2bd806feSTsiChungLiew  *
18*2bd806feSTsiChungLiew  * You should have received a copy of the GNU General Public License
19*2bd806feSTsiChungLiew  * along with this program; if not, write to the Free Software
20*2bd806feSTsiChungLiew  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21*2bd806feSTsiChungLiew  * MA 02111-1307 USA
22*2bd806feSTsiChungLiew  *
23*2bd806feSTsiChungLiew  */
24*2bd806feSTsiChungLiew 
25*2bd806feSTsiChungLiew /*
26*2bd806feSTsiChungLiew  * Minimal serial functions needed to use one of the uart ports
27*2bd806feSTsiChungLiew  * as serial console interface.
28*2bd806feSTsiChungLiew  */
29*2bd806feSTsiChungLiew 
30*2bd806feSTsiChungLiew #include <common.h>
31*2bd806feSTsiChungLiew #include <asm/immap.h>
32*2bd806feSTsiChungLiew #include <asm/uart.h>
33*2bd806feSTsiChungLiew 
34*2bd806feSTsiChungLiew DECLARE_GLOBAL_DATA_PTR;
35*2bd806feSTsiChungLiew 
36*2bd806feSTsiChungLiew #ifdef CONFIG_MCFSERIAL
37*2bd806feSTsiChungLiew int serial_init(void)
38*2bd806feSTsiChungLiew {
39*2bd806feSTsiChungLiew 	volatile uart_t *uart;
40*2bd806feSTsiChungLiew 	u32 counter;
41*2bd806feSTsiChungLiew 
42*2bd806feSTsiChungLiew 	uart = (volatile uart_t *)(CFG_UART_BASE);
43*2bd806feSTsiChungLiew 
44*2bd806feSTsiChungLiew 	/* write to SICR: SIM2 = uart mode,dcd does not affect rx */
45*2bd806feSTsiChungLiew 	uart->ucr = UART_UCR_RESET_RX;
46*2bd806feSTsiChungLiew 	uart->ucr = UART_UCR_RESET_TX;
47*2bd806feSTsiChungLiew 	uart->ucr = UART_UCR_RESET_ERROR;
48*2bd806feSTsiChungLiew 	uart->ucr = UART_UCR_RESET_MR;
49*2bd806feSTsiChungLiew 	__asm__("nop");
50*2bd806feSTsiChungLiew 
51*2bd806feSTsiChungLiew 	uart->uimr = 0;
52*2bd806feSTsiChungLiew 
53*2bd806feSTsiChungLiew 	/* write to CSR: RX/TX baud rate from timers */
54*2bd806feSTsiChungLiew 	uart->ucsr = (UART_UCSR_RCS_SYS_CLK | UART_UCSR_TCS_SYS_CLK);
55*2bd806feSTsiChungLiew 
56*2bd806feSTsiChungLiew 	uart->umr = (UART_UMR_BC_8 | UART_UMR_PM_NONE);
57*2bd806feSTsiChungLiew 	uart->umr = UART_UMR_SB_STOP_BITS_1;
58*2bd806feSTsiChungLiew 
59*2bd806feSTsiChungLiew 	/* Setting up BaudRate */
60*2bd806feSTsiChungLiew 	counter = (u32) (gd->bus_clk / (gd->baudrate));
61*2bd806feSTsiChungLiew 	counter >>= 5;
62*2bd806feSTsiChungLiew 
63*2bd806feSTsiChungLiew 	/* write to CTUR: divide counter upper byte */
64*2bd806feSTsiChungLiew 	uart->ubg1 = (u8) ((counter & 0xff00) >> 8);
65*2bd806feSTsiChungLiew 	/* write to CTLR: divide counter lower byte */
66*2bd806feSTsiChungLiew 	uart->ubg2 = (u8) (counter & 0x00ff);
67*2bd806feSTsiChungLiew 
68*2bd806feSTsiChungLiew 	uart->ucr = (UART_UCR_RX_ENABLED | UART_UCR_TX_ENABLED);
69*2bd806feSTsiChungLiew 
70*2bd806feSTsiChungLiew 	return (0);
71*2bd806feSTsiChungLiew }
72*2bd806feSTsiChungLiew 
73*2bd806feSTsiChungLiew void serial_putc(const char c)
74*2bd806feSTsiChungLiew {
75*2bd806feSTsiChungLiew 	volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE);
76*2bd806feSTsiChungLiew 
77*2bd806feSTsiChungLiew 	if (c == '\n')
78*2bd806feSTsiChungLiew 		serial_putc('\r');
79*2bd806feSTsiChungLiew 
80*2bd806feSTsiChungLiew 	/* Wait for last character to go. */
81*2bd806feSTsiChungLiew 	while (!(uart->usr & UART_USR_TXRDY)) ;
82*2bd806feSTsiChungLiew 
83*2bd806feSTsiChungLiew 	uart->utb = c;
84*2bd806feSTsiChungLiew }
85*2bd806feSTsiChungLiew 
86*2bd806feSTsiChungLiew void serial_puts(const char *s)
87*2bd806feSTsiChungLiew {
88*2bd806feSTsiChungLiew 	while (*s) {
89*2bd806feSTsiChungLiew 		serial_putc(*s++);
90*2bd806feSTsiChungLiew 	}
91*2bd806feSTsiChungLiew }
92*2bd806feSTsiChungLiew 
93*2bd806feSTsiChungLiew int serial_getc(void)
94*2bd806feSTsiChungLiew {
95*2bd806feSTsiChungLiew 	volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE);
96*2bd806feSTsiChungLiew 
97*2bd806feSTsiChungLiew 	/* Wait for a character to arrive. */
98*2bd806feSTsiChungLiew 	while (!(uart->usr & UART_USR_RXRDY)) ;
99*2bd806feSTsiChungLiew 	return uart->urb;
100*2bd806feSTsiChungLiew }
101*2bd806feSTsiChungLiew 
102*2bd806feSTsiChungLiew int serial_tstc(void)
103*2bd806feSTsiChungLiew {
104*2bd806feSTsiChungLiew 	volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE);
105*2bd806feSTsiChungLiew 
106*2bd806feSTsiChungLiew 	return (uart->usr & UART_USR_RXRDY);
107*2bd806feSTsiChungLiew }
108*2bd806feSTsiChungLiew 
109*2bd806feSTsiChungLiew void serial_setbrg(void)
110*2bd806feSTsiChungLiew {
111*2bd806feSTsiChungLiew 	volatile uart_t *uart = (volatile uart_t *)(CFG_UART_BASE);
112*2bd806feSTsiChungLiew 	u32 counter;
113*2bd806feSTsiChungLiew 
114*2bd806feSTsiChungLiew 	counter = ((gd->bus_clk / gd->baudrate)) >> 5;
115*2bd806feSTsiChungLiew 	counter++;
116*2bd806feSTsiChungLiew 
117*2bd806feSTsiChungLiew 	/* write to CTUR: divide counter upper byte */
118*2bd806feSTsiChungLiew 	uart->ubg1 = ((counter & 0xff00) >> 8);
119*2bd806feSTsiChungLiew 	/* write to CTLR: divide counter lower byte */
120*2bd806feSTsiChungLiew 	uart->ubg2 = (counter & 0x00ff);
121*2bd806feSTsiChungLiew 
122*2bd806feSTsiChungLiew 	uart->ucr = UART_UCR_RESET_RX;
123*2bd806feSTsiChungLiew 	uart->ucr = UART_UCR_RESET_TX;
124*2bd806feSTsiChungLiew 
125*2bd806feSTsiChungLiew 	uart->ucr = UART_UCR_RX_ENABLED | UART_UCR_TX_ENABLED;
126*2bd806feSTsiChungLiew }
127*2bd806feSTsiChungLiew #endif				/* CONFIG_MCFSERIAL */
128