1 /* $NetBSD: ns16550.c,v 1.5 1999/06/28 01:20:45 sakamoto Exp $ */ 2 3 /*- 4 * Copyright (C) 1995-1997 Gary Thomas (gdt@linuxppc.org) 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Gary Thomas. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #ifdef CONS_SERIAL 34 /* 35 * NS16550 support 36 */ 37 38 #include <stand.h> 39 #include "boot.h" 40 #include "ns16550.h" 41 42 volatile struct NS16550 * 43 NS16550_init(addr, speed) 44 int addr; 45 int speed; 46 { 47 struct NS16550 *com_port; 48 49 com_port = (struct NS16550 *)(COMBASE + addr); 50 51 com_port->lcr = 0x80; /* Access baud rate */ 52 speed = comspeed(speed); 53 com_port->dll = speed; 54 com_port->dlm = speed >> 8; 55 56 com_port->lcr = 0x03; /* 8 data, 1 stop, no parity */ 57 com_port->mcr = 0x00; 58 com_port->fcr = 0x07; /* Clear & enable FIFOs */ 59 com_port->ier = 0x00; 60 61 return (com_port); 62 } 63 64 void 65 NS16550_putc(com_port, c) 66 volatile struct NS16550 *com_port; 67 int c; 68 { 69 while ((com_port->lsr & LSR_THRE) == 0) 70 ; 71 com_port->thr = c; 72 } 73 74 int 75 NS16550_getc(com_port) 76 volatile struct NS16550 *com_port; 77 { 78 while ((com_port->lsr & LSR_DR) == 0) 79 ; 80 return (com_port->rbr); 81 } 82 83 int 84 NS16550_scankbd(com_port) 85 volatile struct NS16550 *com_port; 86 { 87 if ((com_port->lsr & LSR_DR) == 0) 88 return -1; 89 return (com_port->rbr); 90 } 91 92 int 93 NS16550_test(com_port) 94 volatile struct NS16550 *com_port; 95 { 96 return ((com_port->lsr & LSR_DR) != 0); 97 } 98 #endif /* CONS_SERIAL */ 99