gdb/ppcnbsd-nat.c

   1 /* Native-dependent code for PowerPC's running NetBSD, for GDB.
   2    Copyright 2002, 2004 Free Software Foundation, Inc.
   3    Contributed by Wasabi Systems, 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 <sys/types.h>
  23 #include <sys/ptrace.h>
  24 #include <machine/reg.h>
  25 #include <machine/frame.h>
  26 #include <machine/pcb.h>
  27
  28 #include "defs.h"
  29 #include "inferior.h"
  30 #include "gdb_assert.h"
  31 #include "gdbcore.h"
  32 #include "regcache.h"
  33 #include "bsd-kvm.h"
  34
  35 #include "ppc-tdep.h"
  36 #include "ppcnbsd-tdep.h"
  37
  38 /* Returns true if PT_GETREGS fetches this register.  */
  39 static int
  40 getregs_supplies (int regno)
  41 {
  42   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
  43
  44   return ((regno >= tdep->ppc_gp0_regnum
  45            && regno < tdep->ppc_gp0_regnum + ppc_num_gprs)
  46           || regno == tdep->ppc_lr_regnum
  47           || regno == tdep->ppc_cr_regnum
  48           || regno == tdep->ppc_xer_regnum
  49           || regno == tdep->ppc_ctr_regnum
  50           || regno == PC_REGNUM);
  51 }
  52
  53 /* Like above, but for PT_GETFPREGS.  */
  54 static int
  55 getfpregs_supplies (int regno)
  56 {
  57   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
  58
  59   /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
  60      point registers.  Traditionally, GDB's register set has still
  61      listed the floating point registers for such machines, so this
  62      code is harmless.  However, the new E500 port actually omits the
  63      floating point registers entirely from the register set --- they
  64      don't even have register numbers assigned to them.
  65
  66      It's not clear to me how best to update this code, so this assert
  67      will alert the first person to encounter the NetBSD/E500
  68      combination to the problem.  */
  69   gdb_assert (ppc_floating_point_unit_p (current_gdbarch));
  70
  71   return ((regno >= tdep->ppc_fp0_regnum
  72            && regno < tdep->ppc_fp0_regnum + ppc_num_fprs)
  73           || regno == tdep->ppc_fpscr_regnum);
  74 }
  75
  76 void
  77 fetch_inferior_registers (int regno)
  78 {
  79   if (regno == -1 || getregs_supplies (regno))
  80     {
  81       struct reg regs;
  82
  83       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
  84                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  85         perror_with_name ("Couldn't get registers");
  86
  87       ppcnbsd_supply_reg ((char *) &regs, regno);
  88       if (regno != -1)
  89         return;
  90     }
  91
  92   if (regno == -1 || getfpregs_supplies (regno))
  93     {
  94       struct fpreg fpregs;
  95
  96       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
  97                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
  98         perror_with_name ("Couldn't get FP registers");
  99
 100       ppcnbsd_supply_fpreg ((char *) &fpregs, regno);
 101       if (regno != -1)
 102         return;
 103     }
 104 }
 105
 106 void
 107 store_inferior_registers (int regno)
 108 {
 109   if (regno == -1 || getregs_supplies (regno))
 110     {
 111       struct reg regs;
 112
 113       if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
 114                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 115         perror_with_name ("Couldn't get registers");
 116
 117       ppcnbsd_fill_reg ((char *) &regs, regno);
 118
 119       if (ptrace (PT_SETREGS, PIDGET (inferior_ptid),
 120                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 121         perror_with_name ("Couldn't write registers");
 122
 123       if (regno != -1)
 124         return;
 125     }
 126
 127   if (regno == -1 || getfpregs_supplies (regno))
 128     {
 129       struct fpreg fpregs;
 130
 131       if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
 132                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 133         perror_with_name ("Couldn't get FP registers");
 134
 135       ppcnbsd_fill_fpreg ((char *) &fpregs, regno);
 136
 137       if (ptrace (PT_SETFPREGS, PIDGET (inferior_ptid),
 138                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 139         perror_with_name ("Couldn't set FP registers");
 140     }
 141 }
 142
 143 static int
 144 ppcnbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 145 {
 146   struct switchframe sf;
 147   struct callframe cf;
 148   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
 149   int i;
 150
 151   /* The stack pointer shouldn't be zero.  */
 152   if (pcb->pcb_sp == 0)
 153     return 0;
 154
 155   read_memory (pcb->pcb_sp, (char *) &sf, sizeof sf);
 156   regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr);
 157   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
 158   for (i = 0 ; i < 19 ; i++)
 159     regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 13 + i,
 160                          &sf.fixreg[i]);
 161
 162   read_memory(sf.sp, (char *)&cf, sizeof(cf));
 163   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.r30);
 164   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.r31);
 165   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 1, &cf.sp);
 166
 167   read_memory(cf.sp, (char *)&cf, sizeof(cf));
 168   regcache_raw_supply (regcache, tdep->ppc_lr_regnum, &cf.lr);
 169   regcache_raw_supply (regcache, PC_REGNUM, &cf.lr);
 170
 171   return 1;
 172 }
 173
 174 /* Provide a prototype to silence -Wmissing-prototypes.  */
 175 void _initialize_ppcnbsd_nat (void);
 176
 177 void
 178 _initialize_ppcnbsd_nat (void)
 179 {
 180   /* Support debugging kernel virtual memory images.  */
 181   bsd_kvm_add_target (ppcnbsd_supply_pcb);
 182 }