1/* 2 * BRIEF MODULE DESCRIPTION 3 * Low level uart routines to directly access a TX[34]927 SIO. 4 * 5 * Copyright 2001 MontaVista Software Inc. 6 * Author: MontaVista Software, Inc. 7 * ahennessy@mvista.com or source@mvista.com 8 * 9 * Based on arch/mips/ddb5xxx/ddb5477/kgdb_io.c 10 * 11 * Copyright (C) 2000-2001 Toshiba Corporation 12 * 13 * This program is free software; you can redistribute it and/or modify it 14 * under the terms of the GNU General Public License as published by the 15 * Free Software Foundation; either version 2 of the License, or (at your 16 * option) any later version. 17 * 18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 19 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN 21 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 24 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 25 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * You should have received a copy of the GNU General Public License along 30 * with this program; if not, write to the Free Software Foundation, Inc., 31 * 675 Mass Ave, Cambridge, MA 02139, USA. 32 */ 33 34#include <linux/types.h> 35#include <asm/jmr3927/txx927.h> 36#include <asm/jmr3927/tx3927.h> 37#include <asm/jmr3927/jmr3927.h> 38 39#define TIMEOUT 0xffffff 40#define SLOW_DOWN 41 42static const char digits[16] = "0123456789abcdef"; 43 44#ifdef SLOW_DOWN 45#define slow_down() { int k; for (k=0; k<10000; k++); } 46#else 47#define slow_down() 48#endif 49 50static int remoteDebugInitialized = 0; 51 52int putDebugChar(unsigned char c) 53{ 54 int i = 0; 55 56 if (!remoteDebugInitialized) { 57 remoteDebugInitialized = 1; 58 debugInit(38400); 59 } 60 61 do { 62 slow_down(); 63 i++; 64 if (i>TIMEOUT) { 65 break; 66 } 67 } while (!(tx3927_sioptr(0)->cisr & TXx927_SICISR_TXALS)); 68 tx3927_sioptr(0)->tfifo = c; 69 70 return 1; 71} 72 73unsigned char getDebugChar(void) 74{ 75 int i = 0; 76 int dicr; 77 char c; 78 79 if (!remoteDebugInitialized) { 80 remoteDebugInitialized = 1; 81 debugInit(38400); 82 } 83 84 /* diable RX int. */ 85 dicr = tx3927_sioptr(0)->dicr; 86 tx3927_sioptr(0)->dicr = 0; 87 88 do { 89 slow_down(); 90 i++; 91 if (i>TIMEOUT) { 92 break; 93 } 94 } while (tx3927_sioptr(0)->disr & TXx927_SIDISR_UVALID) 95 ; 96 c = tx3927_sioptr(0)->rfifo; 97 98 /* clear RX int. status */ 99 tx3927_sioptr(0)->disr &= ~TXx927_SIDISR_RDIS; 100 /* enable RX int. */ 101 tx3927_sioptr(0)->dicr = dicr; 102 103 return c; 104} 105 106void debugInit(int baud) 107{ 108 /* 109 volatile unsigned long lcr; 110 volatile unsigned long dicr; 111 volatile unsigned long disr; 112 volatile unsigned long cisr; 113 volatile unsigned long fcr; 114 volatile unsigned long flcr; 115 volatile unsigned long bgr; 116 volatile unsigned long tfifo; 117 volatile unsigned long rfifo; 118 */ 119 120 tx3927_sioptr(0)->lcr = 0x020; 121 tx3927_sioptr(0)->dicr = 0; 122 tx3927_sioptr(0)->disr = 0x4100; 123 tx3927_sioptr(0)->cisr = 0x014; 124 tx3927_sioptr(0)->fcr = 0; 125 tx3927_sioptr(0)->flcr = 0x02; 126 tx3927_sioptr(0)->bgr = ((JMR3927_BASE_BAUD + baud / 2) / baud) | 127 TXx927_SIBGR_BCLK_T0; 128} 129