1 /* $NetBSD: ns16550.c,v 1.1 2002/03/28 20:40:47 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 2002 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Jason R. Thorpe for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /* 39 * This file provides the cons_init() function and console I/O routines 40 * for boards that use 16550-compatible UARTs. 41 */ 42 43 #include <sys/types.h> 44 #include <dev/ic/comreg.h> 45 #include <lib/libsa/stand.h> 46 47 #include "board.h" 48 49 #define INB(x) *((__volatile uint8_t *) (CONADDR + (x))) 50 #define OUTB(x, v) *((__volatile uint8_t *) (CONADDR + (x))) = (v) 51 52 #define ISSET(t,f) ((t) & (f)) 53 54 static int 55 comspeed(int speed) 56 { 57 #define divrnd(n, q) (((n)*2/(q)+1)/2) /* divide and round off */ 58 59 int x, err; 60 61 if (speed <= 0) 62 return (-1); 63 x = divrnd((COM_FREQ / 16), speed); 64 if (x <= 0) 65 return (-1); 66 err = divrnd((COM_FREQ / 16) * 1000, speed * x) - 1000; 67 if (err < 0) 68 err = -err; 69 if (err > COM_TOLERANCE) 70 return (-1); 71 return (x); 72 #undef divrnd 73 } 74 75 void 76 cons_init(void) 77 { 78 int rate; 79 80 OUTB(com_cfcr, LCR_DLAB); 81 rate = comspeed(CONSPEED); 82 OUTB(com_dlbl, rate); 83 OUTB(com_dlbh, rate >> 8); 84 OUTB(com_cfcr, LCR_8BITS); 85 OUTB(com_mcr, MCR_DTR | MCR_RTS); 86 OUTB(com_fifo, 87 FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1); 88 OUTB(com_ier, 0); 89 } 90 91 int 92 getchar(void) 93 { 94 uint8_t stat; 95 96 while (!ISSET(stat = INB(com_lsr), LSR_RXRDY)) 97 /* spin */ ; 98 return (INB(com_data)); 99 } 100 101 static void 102 iputchar(int c) 103 { 104 uint8_t stat; 105 int timo; 106 107 /* Wait for any pending transmission to finish. */ 108 timo = 50000; 109 while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo) 110 /* spin */ ; 111 112 OUTB(com_data, c); 113 114 /* Wait for this transmission to complete. */ 115 timo = 1500000; 116 while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo) 117 /* spin */ ; 118 119 /* Clear any interrupts generated by this transmission. */ 120 (void) INB(com_iir); 121 } 122 123 void 124 putchar(int c) 125 { 126 127 if (c == '\n') 128 iputchar('\r'); 129 iputchar(c); 130 } 131