src/os/linux/avr32/init.c

   1 /*
   2  * Copyright (C) 2003, 2004, 2006, 2007
   3  * Robert Lougher <rob@lougher.org.uk>.
   4  *
   5  * This file is part of JamVM.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2,
  10  * or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  */
  21
  22 //#include <fpu_control.h>
  23 //#include <stdio.h>
  24 #include <sys/syscall.h>
  25 #include <unistd.h>
  26 #include <sys/mman.h>
  27 #include "jam.h"
  28
  29 /* Change floating point precision to double (64-bit) from
  30  * the extended (80-bit) Linux default. */
  31
  32 //void setDoublePrecision() {
  33 //    fpu_control_t cw;
  34 //
  35 //    _FPU_GETCW(cw);
  36 //    cw &= ~_FPU_EXTENDED;
  37 //    cw |= _FPU_DOUBLE;
  38 //    _FPU_SETCW(cw);
  39 //}
  40 #ifdef JEM
  41     //real global trap table used for JEM
  42 //    char *trap_h;
  43 #endif
  44
  45
  46 extern size_t trap_h_size;
  47
  48 static char *trap_handler(void)
  49 {
  50         char *trap;
  51
  52         asm volatile (
  53                 "       mov     %[trap], pc\n"
  54                 "       sub     %[trap], -8\n"  /* Return pointer to trap label */
  55                 "       bral    1f\n"           /* Leave the function */
  56                                                 /* The actual trap-handler */
  57                 "trap:  mov     r12, pc\n"      /* Store trap entry point */
  58                 "       sub     r10, -4\n"
  59                 "       mov     pc, r10\n"
  60                 "       .globl  trap_h_size\n"  /* and its size */
  61                 "trap_h_size:\n"
  62                 "       .word . - trap\n"
  63                 "       .size trap_h_size, . - trap_h_size\n"
  64                 "1:\n"
  65                 : [trap] "=r" (trap)
  66                 );
  67         return trap;
  68 }
  69
  70 void initialisePlatform() {
  71         //TODO: is this needed for avr32?    setDoublePrecision();
  72 #ifdef JEM
  73         /**
  74          * Setup the real traps,the entries are actually loaded when entering
  75          * the interpreter engine
  76          */
  77         char *trap_b, *trap_aligned, *trap_h;
  78         int i;
  79
  80         trap_b = mmap(0, 8192, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
  81         if (trap_b == MAP_FAILED)
  82                 exitVM(1);
  83
  84         trap_aligned = (void *)(((unsigned long)trap_b + 4095) & ~4095);
  85
  86         trap_h = trap_handler();
  87
  88         for (i = 0; i < 24; i++) {
  89                 memcpy(trap_aligned + i * 0x80, trap_h, trap_h_size);
  90                 printf("%p\n", trap_aligned + i * 0x80);
  91         }
  92
  93         syscall(__NR_java_settrap, trap_aligned);
  94 #endif
  95 }