openwrt/package/linux/kernel-source/arch/mips/brcm-boards/generic/gdb_hook.c

   1 /*
   2  * Copyright 2004, Broadcom Corporation
   3  * All Rights Reserved.
   4  *
   5  * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
   6  * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
   7  * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
   8  * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
   9  *
  10  * Carsten Langgaard, carstenl@mips.com
  11  * Copyright (C) 2000 MIPS Technologies, Inc.  All rights reserved.
  12  *
  13  * ########################################################################
  14  *
  15  *  This program is free software; you can distribute it and/or modify it
  16  *  under the terms of the GNU General Public License (Version 2) as
  17  *  published by the Free Software Foundation.
  18  *
  19  *  This program is distributed in the hope it will be useful, but WITHOUT
  20  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  21  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  22  *  for more details.
  23  *
  24  *  You should have received a copy of the GNU General Public License along
  25  *  with this program; if not, write to the Free Software Foundation, Inc.,
  26  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  27  *
  28  * ########################################################################
  29  *
  30  * This is the interface to the remote debugger stub.
  31  *
  32  */
  33
  34 #include <linux/serialP.h>
  35 #include <linux/serial_reg.h>
  36
  37 #include <asm/serial.h>
  38 #include <asm/io.h>
  39
  40 static struct async_struct kdb_port_info = {0};
  41
  42 static __inline__ unsigned int serial_in(struct async_struct *info, int offset)
  43 {
  44         return readb((unsigned long) info->iomem_base +
  45                      (offset<<info->iomem_reg_shift));
  46 }
  47
  48 static __inline__ void serial_out(struct async_struct *info, int offset,
  49                                   int value)
  50 {
  51         writeb(value, (unsigned long) info->iomem_base +
  52                (offset<<info->iomem_reg_shift));
  53 }
  54
  55 void rs_kgdb_hook(struct serial_state *ser) {
  56         int t;
  57
  58         kdb_port_info.state = ser;
  59         kdb_port_info.magic = SERIAL_MAGIC;
  60         kdb_port_info.port = ser->port;
  61         kdb_port_info.flags = ser->flags;
  62         kdb_port_info.iomem_base = ser->iomem_base;
  63         kdb_port_info.iomem_reg_shift = ser->iomem_reg_shift;
  64         kdb_port_info.MCR = UART_MCR_DTR | UART_MCR_RTS;
  65
  66         /*
  67          * Clear all interrupts
  68          */
  69         serial_in(&kdb_port_info, UART_LSR);
  70         serial_in(&kdb_port_info, UART_RX);
  71         serial_in(&kdb_port_info, UART_IIR);
  72         serial_in(&kdb_port_info, UART_MSR);
  73
  74         /*
  75          * Now, initialize the UART
  76          */
  77         serial_out(&kdb_port_info, UART_LCR, UART_LCR_WLEN8);   /* reset DLAB */
  78         serial_out(&kdb_port_info, UART_MCR, kdb_port_info.MCR);
  79
  80         /*
  81          * and set the speed of the serial port
  82          * (currently hardwired to 115200 8N1
  83          */
  84
  85         /* baud rate is fixed to 115200 (is this sufficient?)*/
  86         t = kdb_port_info.state->baud_base / 115200;
  87         /* set DLAB */
  88         serial_out(&kdb_port_info, UART_LCR, UART_LCR_WLEN8 | UART_LCR_DLAB);
  89         serial_out(&kdb_port_info, UART_DLL, t & 0xff);/* LS of divisor */
  90         serial_out(&kdb_port_info, UART_DLM, t >> 8);  /* MS of divisor */
  91         /* reset DLAB */
  92         serial_out(&kdb_port_info, UART_LCR, UART_LCR_WLEN8);
  93 }
  94
  95 int putDebugChar(char c)
  96 {
  97
  98         if (!kdb_port_info.state) {     /* need to init device first */
  99                 return 0;
 100         }
 101
 102         while ((serial_in(&kdb_port_info, UART_LSR) & UART_LSR_THRE) == 0)
 103                 ;
 104
 105         serial_out(&kdb_port_info, UART_TX, c);
 106
 107         return 1;
 108 }
 109
 110 char getDebugChar(void)
 111 {
 112         if (!kdb_port_info.state) {     /* need to init device first */
 113                 return 0;
 114         }
 115
 116         while (!(serial_in(&kdb_port_info, UART_LSR) & 1))
 117                 ;
 118
 119         return(serial_in(&kdb_port_info, UART_RX));
 120 }