gdb/ppcnbsd-nat.c

   1 /* Native-dependent code for NetBSD/powerpc.
   2
   3    Copyright (C) 2002-2015 Free Software Foundation, Inc.
   4
   5    Contributed by Wasabi Systems, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "defs.h"
  23
  24 #include <sys/types.h>
  25 #include <sys/ptrace.h>
  26 #include <machine/reg.h>
  27 #include <machine/frame.h>
  28 #include <machine/pcb.h>
  29
  30 #include "gdbcore.h"
  31 #include "inferior.h"
  32 #include "regcache.h"
  33
  34 #include "ppc-tdep.h"
  35 #include "ppcnbsd-tdep.h"
  36 #include "bsd-kvm.h"
  37 #include "inf-ptrace.h"
  38
  39 /* Returns true if PT_GETREGS fetches this register.  */
  40
  41 static int
  42 getregs_supplies (struct gdbarch *gdbarch, int regnum)
  43 {
  44   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  45
  46   return ((regnum >= tdep->ppc_gp0_regnum
  47            && regnum < tdep->ppc_gp0_regnum + ppc_num_gprs)
  48           || regnum == tdep->ppc_lr_regnum
  49           || regnum == tdep->ppc_cr_regnum
  50           || regnum == tdep->ppc_xer_regnum
  51           || regnum == tdep->ppc_ctr_regnum
  52           || regnum == gdbarch_pc_regnum (gdbarch));
  53 }
  54
  55 /* Like above, but for PT_GETFPREGS.  */
  56
  57 static int
  58 getfpregs_supplies (struct gdbarch *gdbarch, int regnum)
  59 {
  60   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  61
  62   /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
  63      point registers.  Traditionally, GDB's register set has still
  64      listed the floating point registers for such machines, so this
  65      code is harmless.  However, the new E500 port actually omits the
  66      floating point registers entirely from the register set --- they
  67      don't even have register numbers assigned to them.
  68
  69      It's not clear to me how best to update this code, so this assert
  70      will alert the first person to encounter the NetBSD/E500
  71      combination to the problem.  */
  72   gdb_assert (ppc_floating_point_unit_p (gdbarch));
  73
  74   return ((regnum >= tdep->ppc_fp0_regnum
  75            && regnum < tdep->ppc_fp0_regnum + ppc_num_fprs)
  76           || regnum == tdep->ppc_fpscr_regnum);
  77 }
  78
  79 static void
  80 ppcnbsd_fetch_inferior_registers (struct target_ops *ops,
  81                                   struct regcache *regcache, int regnum)
  82 {
  83   struct gdbarch *gdbarch = get_regcache_arch (regcache);
  84
  85   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
  86     {
  87       struct reg regs;
  88
  89       if (ptrace (PT_GETREGS, ptid_get_pid (inferior_ptid),
  90                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  91         perror_with_name (_("Couldn't get registers"));
  92
  93       ppc_supply_gregset (&ppcnbsd_gregset, regcache,
  94                           regnum, &regs, sizeof regs);
  95     }
  96
  97   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
  98     {
  99       struct fpreg fpregs;
 100
 101       if (ptrace (PT_GETFPREGS, ptid_get_pid (inferior_ptid),
 102                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 103         perror_with_name (_("Couldn't get FP registers"));
 104
 105       ppc_supply_fpregset (&ppcnbsd_fpregset, regcache,
 106                            regnum, &fpregs, sizeof fpregs);
 107     }
 108 }
 109
 110 static void
 111 ppcnbsd_store_inferior_registers (struct target_ops *ops,
 112                                   struct regcache *regcache, int regnum)
 113 {
 114   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 115
 116   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
 117     {
 118       struct reg regs;
 119
 120       if (ptrace (PT_GETREGS, ptid_get_pid (inferior_ptid),
 121                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 122         perror_with_name (_("Couldn't get registers"));
 123
 124       ppc_collect_gregset (&ppcnbsd_gregset, regcache,
 125                            regnum, &regs, sizeof regs);
 126
 127       if (ptrace (PT_SETREGS, ptid_get_pid (inferior_ptid),
 128                   (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 129         perror_with_name (_("Couldn't write registers"));
 130     }
 131
 132   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
 133     {
 134       struct fpreg fpregs;
 135
 136       if (ptrace (PT_GETFPREGS, ptid_get_pid (inferior_ptid),
 137                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 138         perror_with_name (_("Couldn't get FP registers"));
 139
 140       ppc_collect_fpregset (&ppcnbsd_fpregset, regcache,
 141                             regnum, &fpregs, sizeof fpregs);
 142
 143       if (ptrace (PT_SETFPREGS, ptid_get_pid (inferior_ptid),
 144                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 145         perror_with_name (_("Couldn't set FP registers"));
 146     }
 147 }
 148
 149 static int
 150 ppcnbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 151 {
 152   struct switchframe sf;
 153   struct callframe cf;
 154   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 155   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 156   int i;
 157
 158   /* The stack pointer shouldn't be zero.  */
 159   if (pcb->pcb_sp == 0)
 160     return 0;
 161
 162   read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf);
 163   regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr);
 164   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
 165   for (i = 0 ; i < 19 ; i++)
 166     regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 13 + i,
 167                          &sf.fixreg[i]);
 168
 169   read_memory(sf.sp, (gdb_byte *)&cf, sizeof(cf));
 170   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.r30);
 171   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.r31);
 172   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 1, &cf.sp);
 173
 174   read_memory(cf.sp, (gdb_byte *)&cf, sizeof(cf));
 175   regcache_raw_supply (regcache, tdep->ppc_lr_regnum, &cf.lr);
 176   regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &cf.lr);
 177
 178   return 1;
 179 }
 180
 181 /* Provide a prototype to silence -Wmissing-prototypes.  */
 182 void _initialize_ppcnbsd_nat (void);
 183
 184 void
 185 _initialize_ppcnbsd_nat (void)
 186 {
 187   struct target_ops *t;
 188
 189   /* Support debugging kernel virtual memory images.  */
 190   bsd_kvm_add_target (ppcnbsd_supply_pcb);
 191
 192   /* Add in local overrides.  */
 193   t = inf_ptrace_target ();
 194   t->to_fetch_registers = ppcnbsd_fetch_inferior_registers;
 195   t->to_store_registers = ppcnbsd_store_inferior_registers;
 196   add_target (t);
 197 }