Subversion Repositories HelenOS-historic

Rev

Go to most recent revision | Blame | Last modification | View Log | Download | RSS feed

  1. /*
  2.  * Copyright (C) 2001-2004 Jakub Jermar
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. #include <arch/exception.h>
  30. #include <panic.h>
  31. #include <arch/cp0.h>
  32. #include <arch/types.h>
  33. #include <arch.h>
  34.  
  35. void exception(void)
  36. {
  37.     int excno;
  38.     __u32 epc;
  39.     pri_t pri;
  40.    
  41.     pri = cpu_priority_high();
  42.     epc = cp0_epc_read();
  43.     cp0_status_write(cp0_status_read() & ~ cp0_status_exl_exception_bit);
  44.  
  45.     if (the->thread) {
  46.         the->thread->saved_pri = pri;
  47.         the->thread->saved_epc = epc;
  48.     }
  49.     /* decode exception number and process the exception */
  50.     switch(excno = (cp0_cause_read()>>2)&0x1f) {
  51.         case EXC_Int: interrupt(); break;
  52.         case EXC_TLBL:
  53.         case EXC_TLBS: tlb_invalid(); break;
  54.         default: panic(PANIC "unhandled exception %d\n", excno); break;
  55.     }
  56.    
  57.     if (the->thread) {
  58.         pri = the->thread->saved_pri;
  59.         epc = the->thread->saved_epc;
  60.     }
  61.  
  62.     cp0_epc_write(epc);
  63.     cp0_status_write(cp0_status_read() | cp0_status_exl_exception_bit);
  64.     cpu_priority_restore(pri);
  65. }
  66.