gdb/ppcobsd-nat.c

   1 /* Native-dependent code for OpenBSD/powerpc.
   2
   3    Copyright 2004, 2005 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (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, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "gdbcore.h"
  24 #include "inferior.h"
  25 #include "regcache.h"
  26
  27 #include <stddef.h>
  28 #include <sys/types.h>
  29 #include <sys/ptrace.h>
  30 #include <sys/signal.h>
  31 #include <machine/frame.h>
  32 #include <machine/pcb.h>
  33 #include <machine/reg.h>
  34
  35 #include "ppc-tdep.h"
  36 #include "ppcobsd-tdep.h"
  37 #include "inf-ptrace.h"
  38 #include "bsd-kvm.h"
  39
  40 /* OpenBSD/powerpc doesn't have PT_GETFPREGS/PT_SETFPREGS like
  41    NetBSD/powerpc and FreeBSD/powerpc.  */
  42
  43 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
  44    for all registers.  */
  45
  46 static void
  47 ppcobsd_fetch_registers (int regnum)
  48 {
  49   struct reg regs;
  50
  51   if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
  52               (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  53     perror_with_name (_("Couldn't get registers"));
  54
  55   ppcobsd_supply_gregset (&ppcobsd_gregset, current_regcache, -1,
  56                           &regs, sizeof regs);
  57 }
  58
  59 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
  60    this for all registers.  */
  61
  62 static void
  63 ppcobsd_store_registers (int regnum)
  64 {
  65   struct reg regs;
  66
  67   if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
  68               (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  69     perror_with_name (_("Couldn't get registers"));
  70
  71   ppcobsd_collect_gregset (&ppcobsd_gregset, current_regcache,
  72                            regnum, &regs, sizeof regs);
  73
  74   if (ptrace (PT_SETREGS, PIDGET (inferior_ptid),
  75               (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  76     perror_with_name (_("Couldn't write registers"));
  77 }
  78 \f
  79
  80 static int
  81 ppcobsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
  82 {
  83   struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
  84   struct switchframe sf;
  85   struct callframe cf;
  86   int i, regnum;
  87
  88   /* The following is true for OpenBSD 3.7:
  89
  90      The pcb contains %r1 (the stack pointer) at the point of the
  91      context switch in cpu_switch().  At that point we have a stack
  92      frame as described by `struct switchframe', and below that a call
  93      frame as described by `struct callframe'.  From this information
  94      we reconstruct the register state as it would look when we are in
  95      cpu_switch().  */
  96
  97   /* The stack pointer shouldn't be zero.  */
  98   if (pcb->pcb_sp == 0)
  99     return 0;
 100
 101   read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf);
 102   regcache_raw_supply (regcache, SP_REGNUM, &sf.sp);
 103   regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr);
 104   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
 105   for (i = 0, regnum = tdep->ppc_gp0_regnum + 13; i < 19; i++, regnum++)
 106     regcache_raw_supply (regcache, regnum, &sf.fixreg[i]);
 107
 108   read_memory (sf.sp, (gdb_byte *)&cf, sizeof cf);
 109   regcache_raw_supply (regcache, PC_REGNUM, &cf.lr);
 110   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.r30);
 111   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.r31);
 112
 113   return 1;
 114 }
 115 \f
 116
 117 /* Provide a prototype to silence -Wmissing-prototypes.  */
 118 void _initialize_ppcobsd_nat (void);
 119
 120 void
 121 _initialize_ppcobsd_nat (void)
 122 {
 123   struct target_ops *t;
 124
 125   /* Add in local overrides.  */
 126   t = inf_ptrace_target ();
 127   t->to_fetch_registers = ppcobsd_fetch_registers;
 128   t->to_store_registers = ppcobsd_store_registers;
 129   add_target (t);
 130
 131   /* General-purpose registers.  */
 132   ppcobsd_reg_offsets.r0_offset = offsetof (struct reg, gpr);
 133   ppcobsd_reg_offsets.pc_offset = offsetof (struct reg, pc);
 134   ppcobsd_reg_offsets.ps_offset = offsetof (struct reg, ps);
 135   ppcobsd_reg_offsets.cr_offset = offsetof (struct reg, cnd);
 136   ppcobsd_reg_offsets.lr_offset = offsetof (struct reg, lr);
 137   ppcobsd_reg_offsets.ctr_offset = offsetof (struct reg, cnt);
 138   ppcobsd_reg_offsets.xer_offset = offsetof (struct reg, xer);
 139   ppcobsd_reg_offsets.mq_offset = offsetof (struct reg, mq);
 140
 141   /* Floating-point registers.  */
 142   ppcobsd_reg_offsets.f0_offset = offsetof (struct reg, fpr);
 143   ppcobsd_reg_offsets.fpscr_offset = -1;
 144
 145   /* AltiVec registers.  */
 146   ppcobsd_reg_offsets.vr0_offset = offsetof (struct vreg, vreg);
 147   ppcobsd_reg_offsets.vscr_offset = offsetof (struct vreg, vscr);
 148   ppcobsd_reg_offsets.vrsave_offset = offsetof (struct vreg, vrsave);
 149
 150   /* Support debugging kernel virtual memory images.  */
 151   bsd_kvm_add_target (ppcobsd_supply_pcb);
 152 }