xref: /rk3399_rockchip-uboot/drivers/serial/serial_xuartlite.c (revision d0ff51ba5d0309dbe9e25ea54f8a0285a6d5db90)
1 /*
2  * (C) Copyright 2008 Michal Simek <monstr@monstr.eu>
3  * Clean driver and add xilinx constant from header file
4  *
5  * (C) Copyright 2004 Atmark Techno, Inc.
6  * Yasushi SHOJI <yashi@atmark-techno.com>
7  *
8  * See file CREDITS for list of people who contributed to this
9  * project.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of
14  * the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24  * MA 02111-1307 USA
25  */
26 
27 #include <config.h>
28 #include <asm/io.h>
29 
30 #ifdef	CONFIG_XILINX_UARTLITE
31 
32 #define RX_FIFO_OFFSET		0 /* receive FIFO, read only */
33 #define TX_FIFO_OFFSET		4 /* transmit FIFO, write only */
34 #define STATUS_REG_OFFSET	8 /* status register, read only */
35 
36 #define SR_TX_FIFO_FULL		0x08 /* transmit FIFO full */
37 #define SR_RX_FIFO_VALID_DATA	0x01 /* data in receive FIFO */
38 #define SR_RX_FIFO_FULL		0x02 /* receive FIFO full */
39 
40 #define UARTLITE_STATUS		(CONFIG_SERIAL_BASE + STATUS_REG_OFFSET)
41 #define UARTLITE_TX_FIFO	(CONFIG_SERIAL_BASE + TX_FIFO_OFFSET)
42 #define UARTLITE_RX_FIFO	(CONFIG_SERIAL_BASE + RX_FIFO_OFFSET)
43 
44 int serial_init(void)
45 {
46 	/* FIXME: Nothing for now. We should initialize fifo, etc */
47 	return 0;
48 }
49 
50 void serial_setbrg(void)
51 {
52 	/* FIXME: what's this for? */
53 }
54 
55 void serial_putc(const char c)
56 {
57 	if (c == '\n')
58 		serial_putc('\r');
59 	while (in_be32(UARTLITE_STATUS) & SR_TX_FIFO_FULL);
60 	out_be32(UARTLITE_TX_FIFO, (unsigned char) (c & 0xff));
61 }
62 
63 void serial_puts(const char * s)
64 {
65 	while (*s) {
66 		serial_putc(*s++);
67 	}
68 }
69 
70 int serial_getc(void)
71 {
72 	while (!(in_be32(UARTLITE_STATUS) & SR_RX_FIFO_VALID_DATA));
73 	return in_be32(UARTLITE_RX_FIFO) & 0xff;
74 }
75 
76 int serial_tstc(void)
77 {
78 	return (in_be32(UARTLITE_STATUS) & SR_RX_FIFO_VALID_DATA);
79 }
80 
81 #endif	/* CONFIG_MICROBLZE */
82