1 /* $NetBSD: ns16550.c,v 1.4 2008/10/30 06:23:13 cliff 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 #ifdef NS16550_AX4 50 #define INB(x) *((volatile uint8_t *) (CONADDR + ((x) * 4))) 51 #define OUTB(x, v) *((volatile uint8_t *) (CONADDR + ((x) * 4))) = (v) 52 #else 53 #define INB(x) *((volatile uint8_t *) (CONADDR + (x))) 54 #define OUTB(x, v) *((volatile uint8_t *) (CONADDR + (x))) = (v) 55 #endif 56 57 #define ISSET(t,f) ((t) & (f)) 58 59 #ifndef NS16550_FREQ 60 #define NS16550_FREQ COM_FREQ 61 #endif 62 63 static int 64 comspeed(int speed) 65 { 66 #define divrnd(n, q) (((n)*2/(q)+1)/2) /* divide and round off */ 67 68 int x, err; 69 70 if (speed <= 0) 71 return (-1); 72 x = divrnd((NS16550_FREQ / 16), speed); 73 if (x <= 0) 74 return (-1); 75 err = divrnd((((quad_t)NS16550_FREQ) / 16) * 1000, speed * x) - 1000; 76 if (err < 0) 77 err = -err; 78 if (err > COM_TOLERANCE) 79 return (-1); 80 return (x); 81 #undef divrnd 82 } 83 84 void 85 cons_init(void) 86 { 87 int rate; 88 89 OUTB(com_cfcr, LCR_DLAB); 90 rate = comspeed(CONSPEED); 91 OUTB(com_dlbl, rate); 92 OUTB(com_dlbh, rate >> 8); 93 OUTB(com_cfcr, LCR_8BITS); 94 OUTB(com_mcr, MCR_DTR | MCR_RTS); 95 OUTB(com_fifo, 96 FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1); 97 OUTB(com_ier, 0); 98 } 99 100 int 101 getchar(void) 102 { 103 uint8_t stat; 104 105 while (!ISSET(stat = INB(com_lsr), LSR_RXRDY)) 106 /* spin */ ; 107 return (INB(com_data)); 108 } 109 110 static void 111 iputchar(int c) 112 { 113 uint8_t stat; 114 int timo; 115 116 /* Wait for any pending transmission to finish. */ 117 timo = 50000; 118 while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo) 119 /* spin */ ; 120 121 OUTB(com_data, c); 122 123 /* Wait for this transmission to complete. */ 124 timo = 1500000; 125 while (!ISSET(stat = INB(com_lsr), LSR_TXRDY) && --timo) 126 /* spin */ ; 127 128 /* Clear any interrupts generated by this transmission. */ 129 (void) INB(com_iir); 130 } 131 132 void 133 putchar(int c) 134 { 135 136 if (c == '\n') 137 iputchar('\r'); 138 iputchar(c); 139 } 140