1 /* $NetBSD: ns16550.c,v 1.3 2005/12/24 20:07:03 perry 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 #ifndef NS16550_FREQ 55 #define NS16550_FREQ COM_FREQ 56 #endif 57 58 static int 59 comspeed(int speed) 60 { 61 #define divrnd(n, q) (((n)*2/(q)+1)/2) /* divide and round off */ 62 63 int x, err; 64 65 if (speed <= 0) 66 return (-1); 67 x = divrnd((NS16550_FREQ / 16), speed); 68 if (x <= 0) 69 return (-1); 70 err = divrnd((((quad_t)NS16550_FREQ) / 16) * 1000, speed * x) - 1000; 71 if (err < 0) 72 err = -err; 73 if (err > COM_TOLERANCE) 74 return (-1); 75 return (x); 76 #undef divrnd 77 } 78 79 void 80 cons_init(void) 81 { 82 int rate; 83 84 OUTB(com_cfcr, LCR_DLAB); 85 rate = comspeed(CONSPEED); 86 OUTB(com_dlbl, rate); 87 OUTB(com_dlbh, rate >> 8); 88 OUTB(com_cfcr, LCR_8BITS); 89 OUTB(com_mcr, MCR_DTR | MCR_RTS); 90 OUTB(com_fifo, 91 FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1); 92 OUTB(com_ier, 0); 93 } 94 95 int 96 getchar(void) 97 { 98 uint8_t stat; 99 100 while (!ISSET(stat = INB(com_lsr), LSR_RXRDY)) 101 /* spin */ ; 102 return (INB(com_data)); 103 } 104 105 static void 106 iputchar(int c) 107 { 108 uint8_t stat; 109 int timo; 110 111 /* Wait for any pending transmission to finish. */ 112 timo = 50000; 113 while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo) 114 /* spin */ ; 115 116 OUTB(com_data, c); 117 118 /* Wait for this transmission to complete. */ 119 timo = 1500000; 120 while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo) 121 /* spin */ ; 122 123 /* Clear any interrupts generated by this transmission. */ 124 (void) INB(com_iir); 125 } 126 127 void 128 putchar(int c) 129 { 130 131 if (c == '\n') 132 iputchar('\r'); 133 iputchar(c); 134 } 135