1 /* $NetBSD: ns16550.c,v 1.5 2008/04/29 15:24:50 tsutsui Exp $ */
2
3 /*-
4 * Copyright (c) 2008 Izumi Tsutsui. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #ifdef CONS_SERIAL
28
29 #include <lib/libsa/stand.h>
30 #include <lib/libkern/libkern.h>
31
32 #include <dev/ic/comreg.h>
33
34 #include <machine/cpu.h>
35
36 #include "boot.h"
37 #include "ns16550.h"
38
39 #define CSR_READ(base, reg) (*(volatile uint8_t *)((base) + (reg)))
40 #define CSR_WRITE(base, reg, val) \
41 do { \
42 *(volatile uint8_t *)((base) + (reg)) = (val); \
43 } while (/* CONSTCOND */ 0)
44
45 void *
com_init(int addr,int speed)46 com_init(int addr, int speed)
47 {
48 uint8_t *com_port;
49
50 com_port = (void *)MIPS_PHYS_TO_KSEG1(COM_BASE + addr);
51
52 CSR_WRITE(com_port, com_lctl, LCR_DLAB);
53 speed = comspeed(speed);
54 CSR_WRITE(com_port, com_dlbl, speed);
55 CSR_WRITE(com_port, com_dlbh, speed >> 8);
56
57 CSR_WRITE(com_port, com_lctl, LCR_PNONE | LCR_8BITS);
58 CSR_WRITE(com_port, com_mcr, MCR_RTS | MCR_DTR);
59 CSR_WRITE(com_port, com_fifo,
60 FIFO_XMT_RST | FIFO_RCV_RST | FIFO_ENABLE);
61 CSR_WRITE(com_port, com_ier, 0);
62
63 return com_port;
64 }
65
66 void
com_putc(void * dev,int c)67 com_putc(void *dev, int c)
68 {
69 volatile uint8_t *com_port = dev;
70
71 while ((CSR_READ(com_port, com_lsr) & LSR_TXRDY) == 0)
72 ;
73
74 CSR_WRITE(com_port, com_data, c);
75 }
76
77 int
com_getc(void * dev)78 com_getc(void *dev)
79 {
80 volatile uint8_t *com_port = dev;
81
82 while ((CSR_READ(com_port, com_lsr) & LSR_RXRDY) == 0)
83 ;
84
85 return CSR_READ(com_port, com_data);
86 }
87
88 int
com_scankbd(void * dev)89 com_scankbd(void *dev)
90 {
91 volatile uint8_t *com_port = dev;
92
93 if ((CSR_READ(com_port, com_lsr) & LSR_RXRDY) == 0)
94 return -1;
95
96 return CSR_READ(com_port, com_data);
97 }
98 #endif /* CONS_SERIAL */
99